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Sample records for negative expiratory pressure

  1. Negative expiratory pressure (NEP) parameters can predict obstructive sleep apnea syndrome in snoring patients.

    Science.gov (United States)

    Rouatbi, Sonia; Tabka, Zouhair; Dogui, Mohamed; Abdelghani, Ahmed; Guénard, Hervé

    2009-01-01

    The objective of this study was to assess whether parameters of the negative expiratory pressure (NEP) technique are able to detect obstructive sleep apnea syndrome (OSAS) in snoring patients. A cross-sectional study included 42 OSAS patients diagnosed by polysomnography (PSG), 34 simple snorers, and 32 healthy subjects. Lung function was measured by using a plethysmograph and the NEP technique was performed with the patient in the seated and supine positions in a random order. The depression was fixed to 5 cmH(2)O. All patients had normal forced expiratory flow/volume loops. Apneic patients had lower Dflow in both positions with a number of oscillations on the expiratory curve obtained with NEP and an expiratory flow limitation (EFL) in the supine position higher than that of other groups (p < 0.05). Changing from the sitting to the supine position raised the EFL of the three groups, with a significant decrease in Dflow and an increase in the number of oscillations in snoring and OSAS patients (p < 0.05). The analysis of variance showed that only the number of oscillations was significantly different between apneic and snoring patients. NEP constitutes a simple and useful tool for the screening OSAS by EFL, especially the number of oscillations obtained with NEP.

  2. Observational study on efficacy of negative expiratory pressure test proposed as screening for obstructive sleep apnea syndrome among commercial interstate bus drivers - protocol study

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    Hirata Raquel P

    2011-12-01

    Full Text Available Abstract Background Obstructive sleep apnea (OSA is a respiratory disease characterized by the collapse of the extrathoracic airway and has important social implications related to accidents and cardiovascular risk. The main objective of the present study was to investigate whether the drop in expiratory flow and the volume expired in 0.2 s during the application of negative expiratory pressure (NEP are associated with the presence and severity of OSA in a population of professional interstate bus drivers who travel medium and long distances. Methods/Design An observational, analytic study will be carried out involving adult male subjects of an interstate bus company. Those who agree to participate will undergo a detailed patient history, physical examination involving determination of blood pressure, anthropometric data, circumference measurements (hips, waist and neck, tonsils and Mallampati index. Moreover, specific questionnaires addressing sleep apnea and excessive daytime sleepiness will be administered. Data acquisition will be completely anonymous. Following the medical examination, the participants will perform a spirometry, NEP test and standard overnight polysomnography. The NEP test is performed through the administration of negative pressure at the mouth during expiration. This is a practical test performed while awake and requires little cooperation from the subject. In the absence of expiratory flow limitation, the increase in the pressure gradient between the alveoli and open upper airway caused by NEP results in an increase in expiratory flow. Discussion Despite the abundance of scientific evidence, OSA is still underdiagnosed in the general population. In addition, diagnostic procedures are expensive, and predictive criteria are still unsatisfactory. Because increased upper airway collapsibility is one of the main determinants of OSA, the response to the application of NEP could be a predictor of this disorder. With the

  3. Peak expiratory flow rate and Pulse Pressure values during the ...

    African Journals Online (AJOL)

    This study assessed the peak expiratory flow rate and pulse pressure during the luteal and menstruation phases of the menstrual cycle. The peak expiratory flow rate and pulse pressure were measured using the Wright's Peak Flow Meter and Mercury Sphygmomanometer respectively. The peak expiratory flow rate and ...

  4. Transpulmonary Pressure Describes Lung Morphology During Decremental Positive End-Expiratory Pressure Trials in Obesity.

    Science.gov (United States)

    Fumagalli, Jacopo; Berra, Lorenzo; Zhang, Changsheng; Pirrone, Massimiliano; Santiago, Roberta R De Santis; Gomes, Susimeire; Magni, Federico; Dos Santos, Glaucia A B; Bennett, Desmond; Torsani, Vinicius; Fisher, Daniel; Morais, Caio; Amato, Marcelo B P; Kacmarek, Robert M

    2017-08-01

    , reestablishing lung elastance and oxygenation while avoiding increased pulmonary vascular resistance. In obesity, low-to-negative values of transpulmonary pressure predict lung collapse and intratidal recruitment/derecruitment. A decremental positive end-expiratory pressure trial preceded by a recruitment maneuver reverses atelectasis, improves lung mechanics, distribution of ventilation and oxygenation, and does not increase pulmonary vascular resistance.

  5. Correlation Between Abdominal Muscle Thickness and Maximal Expiratory Pressure.

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    Ishida, Hiroshi; Suehiro, Tadanobu; Kurozumi, Chiharu; Ono, Koji; Watanabe, Susumu

    2015-11-01

    The activity of abdominal muscles mainly produces high expiratory pressure. These include the rectus abdominis, external oblique, internal oblique, and transverse abdominis muscles. The purpose of this study was to determine whether maximal expiratory pressure is associated with each abdominal muscle thickness at rest. Thirty-nine healthy male volunteers (mean age ± SD, 20.7 ± 2.7 years) participated in the study. The thickness of the right rectus abdominis, external oblique, internal oblique, and transverse abdominis muscles was measured by B-mode sonography in the supine position. The maximal expiratory pressure was obtained with a spirometer in the sitting position. The correlations between each abdominal muscle thickness and maximal expiratory pressure were determined by the Pearson correlation coefficient. The correlation coefficient between the rectus abdominis muscle and maximal expiratory pressure was 0.571 (Pmuscles and maximal expiratory pressure were 0.297 (P = .066), 0.267 (P = .100), and 0.022 (P = .894), respectively. Our results indicate that the rectus abdominis muscle thickness might be more highly correlated with expiratory pressure production than the external oblique, internal oblique, and transverse abdominis muscle thickness. © 2015 by the American Institute of Ultrasound in Medicine.

  6. Effect of Training Frequency on Maximum Expiratory Pressure

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    Anand, Supraja; El-Bashiti, Nour; Sapienza, Christine

    2012-01-01

    Purpose: To determine the effects of expiratory muscle strength training (EMST) frequency on maximum expiratory pressure (MEP). Method: We assigned 12 healthy participants to 2 groups of training frequency (3 days per week and 5 days per week). They completed a 4-week training program on an EMST trainer (Aspire Products, LLC). MEP was the primary…

  7. Circulatory effects of expiratory flow-limited exercise, dynamic hyperinflation and expiratory muscle pressure

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    P. T. Macklem

    2006-12-01

    Full Text Available This article reviews recent research in normal subjects exercising with and without expiratory flow limitation at 1 L·s–1 imposed by a Starling resistor in the expiratory line, and in patients with chronic obstructive pulmonary disease (COPD, using optoelectronic plethysmography to measure respiratory kinematics, combined with mouth, pleural and abdominal pressure measurements, to assess work of breathing and respiratory muscle performance. In normal subjects, flow-limited exercise resulted in the following: 1 Impaired exercise performance due to intolerable dyspnoea; 2 hypercapnia; 3 excessive respiratory muscle recruitment; 4 blood shifts from trunk to extremities; 5 a 10% reduction in cardiac output and a 5% reduction in arterial oxygen saturation, decreasing energy supplies to working respiratory and locomotor muscles. In both normal subjects and in COPD patients, dynamic hyperinflation did not always occur. Those patients that hyperinflated had worse lung function and less work of breathing, but better exercise performance than the others, in whom expiratory muscle recruitment prevented dynamic hyperinflation at the cost of increased work of breathing and excessive oxygen cost of breathing. This established an early competition between respiratory and locomotor muscles for available energy supplies. Dynamic hyperinflation is a better exercise strategy in chronic obstructive pulmonary disease than expiratory muscle recruitment, but the benefit it confers is small.

  8. The effect of positive end-expiratory pressure on pulse pressure ...

    African Journals Online (AJOL)

    The effect of positive end-expiratory pressure on pulse pressure variation. FJ Smith, M Geyser, I Schreuder, PJ Becker. Abstract. Objectives: To determine the effect of different levels of positive end-expiratory pressure (PEEP) on pulse pressure variation (PPV). Design: An observational study. Setting: Operating theatres of a ...

  9. Effects of positive end-expiratory pressure on renal function.

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    Järnberg, P O; de Villota, E D; Eklund, J; Granberg, P O

    1978-01-01

    The effects were studied positive end-expiratory pressure (PEEP) on renal function in eight patients with acute respiratory failure, requiring mechanical ventilation. On application of PEEP + 10 cm H2O, central venous pressure increased, systolic blood pressure decreased, urine flow and PAH-clearance were reduced, while inulin clearance remained stable. There was a marked increase in fractional sodium reabsorption and a concurrent decrease in fractional osmolal excretion. Fractional free-water clearance and the ratio UOsm/POsm did change.

  10. Changes in Peak Expiratory Flow Rate, Blood Pressure and Pulse ...

    African Journals Online (AJOL)

    We studied the effect of different concentrations of coffee on peak expiratory flow rate (PEFR), blood pressure and pulse rate in an attempt to determine some physiological effects of coffee intake. 18 apparently healthy adult males, age range 20 to 30 years, were recruited for the study over a three day period. Varying ...

  11. Maximum static inspiratory and expiratory pressures with different lung volumes

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    Johnson Monique M

    2006-05-01

    Full Text Available Abstract Background Maximum pressures developed by the respiratory muscles can indicate the health of the respiratory system, help to determine maximum respiratory flow rates, and contribute to respiratory power development. Past measurements of maximum pressures have been found to be inadequate for inclusion in some exercise models involving respiration. Methods Maximum inspiratory and expiratory airway pressures were measured over a range of lung volumes in 29 female and 19 male adults. A commercial bell spirometry system was programmed to occlude airflow at nine target lung volumes ranging from 10% to 90% of vital capacity. Results In women, maximum expiratory pressure increased with volume from 39 to 61 cmH2O and maximum inspiratory pressure decreased with volume from 66 to 28 cmH2O. In men, maximum expiratory pressure increased with volume from 63 to 97 cmH2O and maximum inspiratory pressure decreased with volume from 97 to 39 cmH2O. Equations describing pressures for both sexes are: Pe/Pmax = 0.1426 Ln( %VC + 0.3402 R2 = 0.95 Pi/Pmax = 0.234 Ln(100 - %VC - 0.0828 R2 = 0.96 Conclusion These results were found to be consistent with values and trends obtained by other authors. Regression equations may be suitable for respiratory mechanics models.

  12. Effects of duty cycle and positive end-expiratory pressure on mucus clearance during mechanical ventilation*.

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    Li Bassi, Gianluigi; Saucedo, Lina; Marti, Joan-Daniel; Rigol, Montserrat; Esperatti, Mariano; Luque, Nestor; Ferrer, Miquel; Gabarrus, Albert; Fernandez, Laia; Kolobow, Theodor; Torres, Antoni

    2012-03-01

    During mechanical ventilation, air flows may play a role in mucus transport via two-phase gas liquid flow. The aim of this study was to evaluate effects of duty cycles and positive end-expiratory pressure on mucus clearance in pigs using mechanical ventilation, and to assess their safety. Prospective randomized animal study. Animal research facility, University of Barcelona, Spain. Eight healthy pigs. Pigs were intubated and on volume-control mechanical ventilation for up to 84 hrs. After 4, 24, 48, and 72 hrs of mechanical ventilation, six levels of duty cycle (0.26, 0.33, 0.41, 0.50, 0.60, and 0.75) with no associated positive end-expiratory pressure or 5 cm H2O of positive end-expiratory pressure were randomly applied. Surgical bed was oriented 30 degrees in the reverse Trendelenburg position, as in the semirecumbent position. Inspiratory and expiratory flows and hemodynamics were measured after each 30-min ventilation period. Mucus movement was assessed through fluoroscopy tracking of radio-opaque markers. Mucus velocity was described by a positive vector (toward the glottis) or negative vector (toward the lungs). No effect of positive end-expiratory pressure was found; however, as duty cycle was increasingly prolonged, a trend toward reduced velocity of mucus moving toward the lungs and increased outward mucus velocity was found (p = .064). Two clusters of mucus velocities were identified as duty cycle was prolonged beyond 0.41. Thus, duty cycle >0.41 increased mean expiratory-inspiratory flow bias from -4.1 ± 4.6 to 7.9 ± 5.9 L/min (p < .0001) and promoted outward mucus velocity from -0.22 ± 1.71 mm/min (range, -5.78 to 2.42) to 0.53 ± 1.06 mm/min (-1.91 to 3.88; p = .0048). Duty cycle of 0.75 resulted in intrinsic positive end-expiratory pressure (2.1 ± 1.1 cm H2O [p < .0001] vs. duty cycle 0.26-0.5), with no hemodynamic compromise. In the semirecumbent position, mucus clearance is improved with prolongation of the duty cycle. However, in clinical

  13. A study of experimental acute lung injury in pigs on zero end-expiratory pressure.

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    Guérin, Claude; Levrat, Albrice; Pontier, Sandrine; Annat, Guy

    2008-03-01

    Tidal expiratory flow limitation (EFL) has been reported in humans with acute lung injury (ALI) and assumed to be associated with small airway closure. Detection of EFL is important because by selecting positive end-expiratory pressure at such a level that EFL is no longer present in the tidal breath, the repeated opening and closure of small airways can be prevented. The objective of this study was to investigate the occurrence of EFL in two experimental models of ALI. Ten female piglets. Animals were anaesthetized, tracheotomized and mechanically ventilated on zero end-expiratory pressure. Acute lung injury was induced by oleic acid (OA) (n = 5) or saline lavage (SL) (n = 5). Tidal EFL was assessed by the negative expiratory pressure test. Lung and chest wall mechanics were partitioned using an oesophageal balloon. Resistance and static elastance were assessed by a rapid airway occlusion technique at baseline ventilatory settings. There was no EFL at any time before and after ALI in both models. This may be due to an increased elastance which promoted higher expiratory flow after ALI and to a decreased chest wall to lung static elastance ratio which could favour small airways patency. The similar increase in total lung resistance, in the two models, after ALI was mostly due to an increased airway resistance in the OA model and to the lung tissue resistance in the SL model. Tidal EFL was not detected in experimental ALI. This finding casts some doubt about the usefulness of some experimental models of ALI to mimic some reported findings in human ALI.

  14. Interaction between intra-abdominal pressure and positive-end expiratory pressure

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    Jamili Anbar Torquato

    2009-02-01

    Full Text Available OBJECTIVE: The aim of this study was to quantify the interaction between increased intra-abdominal pressure and Positive-End Expiratory Pressure. METHODS: In 30 mechanically ventilated ICU patients with a fixed tidal volume, respiratory system plateau and abdominal pressure were measured at a Positive-End Expiratory Pressure level of zero and 10 cm H2O. The measurements were repeated after placing a 5 kg weight on the patients' belly. RESULTS: After the addition of 5 kg to the patients' belly at zero Positive-End Expiratory Pressure, both intra-abdominal pressure (p<0.001 and plateau pressures (p=0.005 increased significantly. Increasing the Positive-End Expiratory Pressure levels from zero to 10 cm H2O without weight on the belly did not result in any increase in intra-abdominal pressure (p=0.165. However, plateau pressures increased significantly (p< 0.001. Increasing Positive-End Expiratory Pressure from zero to 10 cm H2O and adding 5 kg to the belly increased intra-abdominal pressure from 8.7 to 16.8 (p<0.001 and plateau pressure from 18.26 to 27.2 (p<0.001. Maintaining Positive-End Expiratory Pressure at 10 cm H2O and placing 5 kg on the belly increased intra-abdominal pressure from 12.3 +/- 1.7 to 16.8 +/- 1.7 (p<0.001 but did not increase plateau pressure (26.6+/-1.2 to 27.2 +/-1.1 -p=0.83. CONCLUSIONS: The addition of a 5kg weight onto the abdomen significantly increased both IAP and the airway plateau pressure, confirming that intra-abdominal hypertension elevates the plateau pressure. However, plateau pressure alone cannot be considered a good indicator for the detection of elevated intra-abdominal pressure in patients under mechanical ventilation using PEEP. In these patients, the intra-abdominal pressure must also be measured.

  15. Effects of the positive end-expiratory pressure increase on sublingual microcirculation in patients with acute respiratory distress syndrome

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    Nathaly Fonseca Nunes

    Full Text Available Abstract Objective: The aim of this study was to evaluate the impact of increased positive end-expiratory pressure on the sublingual microcirculation. Methods: Adult patients who were sedated, under mechanical ventilation, and had a diagnosis of circulatory shock and acute respiratory distress syndrome were included. The positive end-expiratory pressure level was settled to obtain a plateau pressure of 30 cm H2O and then maintained at this level for 20 minutes. Microcirculatory (obtained by videomicroscopy and hemodynamic variables were collected at baseline and compared with those at the end of 20 min. Results: Twelve patients were enrolled. Overall, the microcirculation parameters did not significantly change after increasing the positive end-expiratory pressure. However, there was considerable interindividual variability. There was a negative, moderate correlation between the changes in the De Backer score (r = -0.58, p = 0.048, total vessel density (r = -0.60, p = 0.039 and baseline values. The changes in total vessel density (r = 0.54, p = 0.07 and perfused vessel density (r = 0.52, p = 0.08 trended toward correlating with the changes in the mean arterial pressure. Conclusion: Overall, the microcirculation parameters did not significantly change after increasing the positive end-expiratory pressure. However, at individual level, such response was heterogeneous. The changes in the microcirculation parameters could be correlated with the baseline values and changes in the mean arterial pressure.

  16. EFFECT OF POSITIVE EXPIRATORY PRESSURE ON BREATHING PATTERN IN HEALTHY-SUBJECTS

    NARCIS (Netherlands)

    VANDERSCHANS, CP; DEJONG, W; DEVRIES, G; POSTMA, DS; KOETER, GH; VANDERMARK, TW

    The purpose of this study was to register breathing patterns, in healthy subjects, during breathing with a positive expiratory pressure. Integrated electromyographic (IEMG) activity of the following muscles was assessed: scalene muscle, parasternal muscle and abdominal muscles, using surface

  17. Unidirectional Expiratory Valve Method to Assess Maximal Inspiratory Pressure in Individuals without Artificial Airway.

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    Samantha Torres Grams

    Full Text Available Maximal Inspiratory Pressure (MIP is considered an effective method to estimate strength of inspiratory muscles, but still leads to false positive diagnosis. Although MIP assessment with unidirectional expiratory valve method has been used in patients undergoing mechanical ventilation, no previous studies investigated the application of this method in subjects without artificial airway.This study aimed to compare the MIP values assessed by standard method (MIPsta and by unidirectional expiratory valve method (MIPuni in subjects with spontaneous breathing without artificial airway. MIPuni reproducibility was also evaluated.This was a crossover design study, and 31 subjects performed MIPsta and MIPuni in a random order. MIPsta measured MIP maintaining negative pressure for at least one second after forceful expiration. MIPuni evaluated MIP using a unidirectional expiratory valve attached to a face mask and was conducted by two evaluators (A and B at two moments (Tests 1 and 2 to determine interobserver and intraobserver reproducibility of MIP values. Intraclass correlation coefficient (ICC[2,1] was used to determine intraobserver and interobserver reproducibility.The mean values for MIPuni were 14.3% higher (-117.3 ± 24.8 cmH2O than the mean values for MIPsta (-102.5 ± 23.9 cmH2O (p<0.001. Interobserver reproducibility assessment showed very high correlation for Test 1 (ICC[2,1] = 0.91, and high correlation for Test 2 (ICC[2,1] = 0.88. The assessment of the intraobserver reproducibility showed high correlation for evaluator A (ICC[2,1] = 0.86 and evaluator B (ICC[2,1] = 0.77.MIPuni presented higher values when compared with MIPsta and proved to be reproducible in subjects with spontaneous breathing without artificial airway.

  18. Effects of positive end-expiratory pressure on the sigmoid equation in experimental acute lung injury.

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    Bayle, Frederique; Guerin, Claude; Viale, Jean-Paul; Richard, Jean-Christophe; Annat, Guy

    2004-11-01

    To describe inflation and deflation volume-pressure (V-P) curves of the respiratory system by the sigmoidal equation at different levels of positive end-expiratory pressure (PEEP) in acute lung injury. Experimental study. Physiological laboratory in a university setting. Six pigs of 25 kg each. Acute lung injury was induced by oleic acid. PEEP was applied from 0 to 15 cm H(2)O and from 15 to 0 cm H(2)O for 10 min in steps of 5 cmH(2)O. Inflation and deflation V-P curves were constructed from an automated super-syringe that delivers a constant flow of 7 l/min in both inspiratory and expiratory directions. V-P curves were obtained at each level of PEEP without disconnecting the animal from the ventilator. The experimental data were fitted to the sigmoid equation which provided the true inflection point (c), the point of maximal compliance increase (Pmci) reflecting opening/closure and the point of maximal compliance decrease (Pmcd) reflecting end of recruitment/onset of de-recruitment. The sigmoid equation provided an excellent fit. The values of the coefficients of determination were greater than 0.970 (median 0.996, IQR 0.994-0.997 for the 84 determinations). Negative values of Pmci in the deflation limb of the V-P curve were recorded in five pigs, suggesting closure below the volume range studied. Inflation and deflation V-P curves at different PEEPs can be fitted by the sigmoid equation. However, further work is needed to investigate the meaning of negative values for Pmci.

  19. EFFECTS OF POSITIVE EXPIRATORY PRESSURE BREATHING DURING EXERCISE IN PATIENTS WITH COPD

    NARCIS (Netherlands)

    VANDERSCHANS, GP; DEJONG, W; DEVRIES, G; KAAN, WA; POSTMA, DS; KOETER, GH; VANDERMARK, TW

    The effect of breathing with a positive expiratory pressure of 5 cm H2O was investigated in eight patients with COPD (mean [SD] FEV(1) = 54 [13] percent predicted). Specific work of breathing (Wsp) and myoelectrical activity of the following respiratory muscles were measured at rest: scalene muscle,

  20. EFFECT OF POSITIVE EXPIRATORY PRESSURE BREATHING IN PATIENTS WITH CYSTIC-FIBROSIS

    NARCIS (Netherlands)

    VANDERSCHANS, CP; VANDERMARK, TW; DEVRIES, G; PIERS, DA; BEEKHUIS, H; DANKERTROELSE, JE; POSTMA, DS; KOETER, GH

    The effect of positive expiratory pressure breathing, alone and in combination with coughing, was investigated in eight patients with cystic fibrosis. Functional residual capacity and total lung capacity was measured with a body plethysmograph before, during, and immediately after breathing with

  1. Pharmacologic Interventions to Improve Splanchnic Oxygenation During Ventilation with Positive End-Expiratory Pressure

    NARCIS (Netherlands)

    Fournell, A.; Scheeren, T. W. L.; Picker, O.; Schwarte, L. A.; Wolf, M; Bucher, HU; Rudin, M; VanHuffel, S; Wolf, U; Bruley, DF; Harrison, DK

    2012-01-01

    Mechanical ventilation with positive end-expiratory pressure (PEEP) is an indispensable tool in the management of respiratory failure to preserve or improve lung function and systemic oxygenation. However, PEEP per se may also, as has been shown in experimental animals, impair regional

  2. Maximal hysteresis: a new method to set positive end-expiratory pressure in acute lung injury?

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    Koefoed-Nielsen, J; Andersen, G; Barklin, A; Bach, A; Lunde, S; Tønnesen, E; Larsson, A

    2008-05-01

    No methods are superior when setting positive end-expiratory pressure (PEEP) in acute lung injury (ALI). In ALI, the vertical distance (hysteresis) between the inspiratory and expiratory limbs of a static pressure-volume (PV) loop mainly indicates lung recruitment. We hypothesized that PEEP set at the pressure where hysteresis is 90% of its maximum (90%MH) would give similar oxygenation, but less cardiovascular depression than PEEP set at the pressure at lower inflection point (LIP) on the inspiratory limb or at the point of maximal curvature (PMC) on the expiratory limb in ALI. In 12 mechanically ventilated pigs, ALI was induced in a randomized fashion by lung lavage, lung lavage plus injurious ventilation, or by oleic acid. From a static PV loop obtained by an interrupted low-flow method, the pressures at LIP [25 (25, 25) cmH(2)O, mean and 25, 75 percentiles], at PMC [24 (20, 24) cmH(2)O], and at 90% MH [19 (18, 19) cmH(2)O] were determined and used for the PEEP-settings. We measured lung inflation (by computed tomography), end-expiratory lung volume (EELV), airway pressures, compliance of the respiratory system (Crs), blood gases, cardiac output and arterial blood pressure. There were no differences between the PEEP settings in EELV or oxygenation, but the 90%MH setting gave lower end-inspiratory pause pressure (P<0.025), higher Crs (P<0.025), less hyper-aeration (P<0.025) and better maintained hemodynamics. In this porcine lung injury model, PEEP set at 90% MH gave better lung mechanics and hemodynamics, than PEEP set at PMC or LIP.

  3. [Negative pressure therapy: NPT].

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    Maillard, H

    2015-01-01

    Negative pressure therapy or treatment (NPT) is used very frequently in hospitals in both surgical and medical departments. NPT consists of maintaining the wound surface at a pressure below ambient atmospheric pressure by means of a specially designed dressing attached to a depressurisation device as well as a system to drain exudate. NPT has been shown to be beneficial in increasing blood flow, thanks to feedback resulting from the decreased oxygen pressure, angiogenesis and reduction of the wound surface area. The French Health Authority (HAS) has issued recommendations for good use in a specific and limited series of applications. NPT may be used in post-traumatic or post-surgical wounds, burns, and in chronic wounds, such as bedsores and ulcers. It is also effective as an adjuvant treatment for infected wounds. In recent years, various different NPT devices have become commercially available. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  4. The Effect of Positive End-Expiratory Pressure on Intracranial Pressure and Cerebral Hemodynamics.

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    Boone, Myles D; Jinadasa, Sayuri P; Mueller, Ariel; Shaefi, Shahzad; Kasper, Ekkehard M; Hanafy, Khalid A; O'Gara, Brian P; Talmor, Daniel S

    2017-04-01

    Lung protective ventilation has not been evaluated in patients with brain injury. It is unclear whether applying positive end-expiratory pressure (PEEP) adversely affects intracranial pressure (ICP) and cerebral perfusion pressure (CPP). We aimed to evaluate the effect of PEEP on ICP and CPP in a large population of patients with acute brain injury and varying categories of acute lung injury, defined by PaO 2 /FiO 2 . Retrospective data were collected from 341 patients with severe acute brain injury admitted to the ICU between 2008 and 2015. These patients experienced a total of 28,644 paired PEEP and ICP observations. Demographic, hemodynamic, physiologic, and ventilator data at the time of the paired PEEP and ICP observations were recorded. In the adjusted analysis, a statistically significant relationship between PEEP and ICP and PEEP and CPP was found only among observations occurring during periods of severe lung injury. For every centimeter H 2 O increase in PEEP, there was a 0.31 mmHg increase in ICP (p = 0.04; 95 % CI [0.07, 0.54]) and a 0.85 mmHg decrease in CPP (p = 0.02; 95 % CI [-1.48, -0.22]). Our results suggest that PEEP can be applied safely in patients with acute brain injury as it does not have a clinically significant effect on ICP or CPP. Further prospective studies are required to assess the safety of applying a lung protective ventilation strategy in brain-injured patients with lung injury.

  5. Short-term effects of positive expiratory airway pressure in patients being weaned from mechanical ventilation

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    Marcelo de Mello Rieder

    2009-05-01

    Full Text Available OBJECTIVE: To investigate the feasibility and the cardiorespiratory effects of using positive expiratory airway pressure, a physiotherapeutic tool, in comparison with a T-tube, to wean patients from mechanical ventilation. METHODS/DESIGN: A prospective, randomized, cross-over study. SETTING: Two intensive care units. PATIENTS AND INTERVENTIONS: We evaluated forty patients who met weaning criteria and had been mechanically-ventilated for more than 48 hours, mean age 59 years, including 23 males. All patients were submitted to the T-tube and Expiratory Positive Airway Pressure devices, at 7 cm H2O, during a 30-minute period. Cardiorespiratory variables including work of breathing, respiratory rate (rr, peripheral oxygen saturation (SpO2, heart rate (hr, systolic, diastolic and mean arterial pressures (SAP, DAP, MAP were measured in the first and thirtieth minutes. The condition was analyzed as an entire sample set (n=40 and was also divided into subconditions: chronic obstructive pulmonary disease (n=14 and non-chronic obstructive pulmonary disease (non- chronic obstructive pulmonary disease (n=26 categories. Comparisons were made using a t-test and Analysis of Variance. The level of significance was p < 0.05. RESULTS: Our data showed an increase in work of breathing in the first and thirtieth minutes in the EPAP condition (0.86+ 0.43 and 1.02+1.3 as compared with the T-tube condition (0.25+0.26 and 0.26+0.35 (p<0.05, verified by the flow-sensor monitor (values in J/L. No statistical differences were observed when comparing the Expiratory Positive Airway Pressure and T-tube conditions with regard to cardiorespiratory measurements. The same result was observed for both chronic obstructive pulmonary disease and non- chronic obstructive pulmonary disease subconditions. CONCLUSIONS: Our study demonstrated that, in weaning patients from mechanical ventilation, the use of a fixed level of Expiratory Positive Airway Pressure caused an increase in work of

  6. High-inflation pressure and positive end-expiratory pressure. Injurious to the lung? No.

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    Nelson, L D

    1996-07-01

    during ARDS) and limiting exposure to toxic concentrations of oxygen minimize ventilator-induced secondary lung injury and maximize chances for survival. Arbitrary limitations of peak inspiratory or end-expiratory airway pressure or mandatory tidal volume in patients with severe ARDS seem to be unfounded. Failure to achieve adequate physiologic end-points in these patients may increase morbidity and mortality rates.

  7. Benefit of educational feedback for the use of positive expiratory pressure device

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    Reychler, Gregory; Jacquemart, Manon; Poncin, William; Aubriot, Anne-Sophie; Liistro, Giuseppe

    2015-01-01

    BACKGROUND: Positive expiratory pressure (PEP) is regularly used as a self-administered airway clearance technique. OBJECTIVE: The aim of this study was to evaluate the need to teach the correct use of the PEP device and to measure the progress of the success rate of the maneuver after training. METHOD: A PEP system (PariPEP-S Sytem) was used to generate PEP in 30 healthy volunteers. They were instructed by a qualified physical therapist to breathe correctly through the PEP device. Then they were evaluated during a set of ten expirations. Two other evaluations were performed at day 2 and day 8 (before and after feedback). The mean PEP and the success rate were calculated for each set of expirations. The number of maneuvers needed to obtain a correct use was calculated on the first session. RESULTS: An optimal PEP was reached after 7.5 SD 2.7 attempts by all subjects. Success rates and mean pressures were similar between the different sets of expirations (p=0.720 and p=0.326, respectively). Pressure variability was around 10%. After one week, 30% of subjects generated more than two non-optimal pressures in the set of ten expirations. No difference in success rate was observed depending on the evaluations. CONCLUSION: This study demonstrates that good initial training on the use of the PEP device and regular follow-up are required for the subject to reach optimal expiratory pressure. PMID:26647746

  8. Control of positive end-expiratory pressure (PEEP for small animal ventilators

    Directory of Open Access Journals (Sweden)

    Leão Nunes Marcelo V

    2010-07-01

    Full Text Available Abstract Background The positive end-expiratory pressure (PEEP for the mechanical ventilation of small animals is frequently obtained with water seals or by using ventilators developed for human use. An alternative mechanism is the use of an on-off expiratory valve closing at the moment when the alveolar pressure is equal to the target PEEP. In this paper, a novel PEEP controller (PEEP-new and the PEEP system of a commercial small-animal ventilator, both based on switching an on-off valve, are evaluated. Methods The proposed PEEP controller is a discrete integrator monitoring the error between the target PEEP and the airways opening pressure prior to the onset of an inspiratory cycle. In vitro as well as in vivo experiments with rats were carried out and the PEEP accuracy, settling time and under/overshoot were considered as a measure of performance. Results The commercial PEEP controller did not pass the tests since it ignores the airways resistive pressure drop, resulting in a PEEP 5 cmH2O greater than the target in most conditions. The PEEP-new presented steady-state errors smaller than 0.5 cmH2O, with settling times below 10 s and under/overshoot smaller than 2 cmH2O. Conclusion The PEEP-new presented acceptable performance, considering accuracy and temporal response. This novel PEEP generator may prove useful in many applications for small animal ventilators.

  9. Limited predictability of maximal muscular pressure using the difference between peak airway pressure and positive end-expiratory pressure during proportional assist ventilation (PAV)

    OpenAIRE

    Su, Po-Lan; Kao, Pei-Shan; Lin, Wei-Chieh; Su, Pei-Fang; Chen, Chang-Wen

    2016-01-01

    Background If the proportional assist ventilation (PAV) level is known, muscular effort can be estimated from the difference between peak airway pressure and positive end-expiratory pressure (PEEP) (?P) during PAV. We conjectured that deducing muscle pressure from ?P may be an interesting method to set PAV, and tested this hypothesis using the oesophageal pressure time product calculation. Methods Eleven mechanically ventilated patients with oesophageal pressure monitoring under PAV were enro...

  10. Relationship of end-expiratory pressure, lung volume, and /sup 99m/Tc-DTPA clearance

    International Nuclear Information System (INIS)

    Cooper, J.A.; van der Zee, H.; Line, B.R.; Malik, A.B.

    1987-01-01

    We investigated the dose-response effect of positive end-expiratory pressure (PEEP) and increased lung volume on the pulmonary clearance rate of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA). Clearance of lung radioactivity was expressed as percent decrease per minute. Base-line clearance was measured while anesthetized sheep (n = 20) were ventilated with 0 cmH 2 O end-expiratory pressure. Clearance was remeasured during ventilation at 2.5, 5, 10, 15, or 20 cmH 2 O PEEP. Further studies showed stepwise increases in functional residual capacity (FRC) (P less than 0.05) measured at 0, 2.5, 5, 10, 15, and 20 cmH 2 O PEEP. At 2.5 cmH 2 O PEEP, the clearance rate was not different from that at base line (P less than 0.05), although FRC was increased from base line. Clearance rate increased progressively with increasing PEEP at 5, 10, and 15 cmH 2 O (P less than 0.05). Between 15 and 20 cmH 2 O PEEP, clearance rate was again unchanged, despite an increase in FRC. The pulmonary clearance of aerosolized /sup 99m/Tc-DTPA shows a sigmoidal response to increasing FRC and PEEP, having both threshold and maximal effects. This relationship is most consistent with the hypothesis that alveolar epithelial permeability is increased by lung inflation

  11. Thermodynamics of negative absolute pressures

    International Nuclear Information System (INIS)

    Lukacs, B.; Martinas, K.

    1984-03-01

    The authors show that the possibility of negative absolute pressure can be incorporated into the axiomatic thermodynamics, analogously to the negative absolute temperature. There are examples for such systems (GUT, QCD) processing negative absolute pressure in such domains where it can be expected from thermodynamical considerations. (author)

  12. Measurements of exhaled nitric oxide with the single-breath technique and positive expiratory pressure in infants.

    Science.gov (United States)

    Wildhaber, J H; Hall, G L; Stick, S M

    1999-01-01

    The aim of this study was to adapt the single-breath technique with positive expiratory pressure to measure exhaled nitric oxide (eNO) in infants. We hypothesized that exhaled eNO was greater in wheezy than in healthy infants. We studied 30 infants (16 wheezy and 14 healthy). The forced expiratory volume in 0.5 s (FEV0.5) was determined with the raised volume rapid thoracic compression technique, and eNO was measured during constant expiratory flow with a rapid-response chemiluminescence analyzer. After passive inflation to a preset pressure of 20 cm H2O, thoracic compression with an inflatable jacket caused forced expiration to occur through a face-mask with an expiratory flow resistor attached. During the forced expiration, the jacket pressure was increased to maintain a constant driving mouth pressure and hence a constant expiratory flow (50 ml/s). The mean level of eNO in the wheezy infants (31.8 ppb) was significantly higher than the level in healthy infants (18.8 ppb) (p = 0.03). A family history of atopy in parents was associated with increased eNO levels (p history of atopy.

  13. Using an expiratory resistor, arterial pulse pressure variations predict fluid responsiveness during spontaneous breathing: an experimental porcine study.

    Science.gov (United States)

    Dahl, Michael K; Vistisen, Simon T; Koefoed-Nielsen, Jacob; Larsson, Anders

    2009-01-01

    Fluid responsiveness prediction is difficult in spontaneously breathing patients. Because the swings in intrathoracic pressure are minor during spontaneous breathing, dynamic parameters like pulse pressure variation (PPV) and systolic pressure variation (SPV) are usually small. We hypothesized that during spontaneous breathing, inspiratory and/or expiratory resistors could induce high arterial pressure variations at hypovolemia and low variations at normovolemia and hypervolemia. Furthermore, we hypothesized that SPV and PPV could predict fluid responsiveness under these conditions. Eight prone, anesthetized and spontaneously breathing pigs (20 to 25 kg) were subjected to a sequence of 30% hypovolemia, normovolemia, and 20% and 40% hypervolemia. At each volemic level, the pigs breathed in a randomized order either through an inspiratory and/or an expiratory threshold resistor (7.5 cmH2O) or only through the tracheal tube without any resistor. Hemodynamic and respiratory variables were measured during the breathing modes. Fluid responsiveness was defined as a 15% increase in stroke volume (DeltaSV) following fluid loading. Stroke volume was significantly lower at hypovolemia compared with normovolemia, but no differences were found between normovolemia and 20% or 40% hypervolemia. Compared with breathing through no resistor, SPV was magnified by all resistors at hypovolemia whereas there were no changes at normovolemia and hypervolemia. PPV was magnified by the inspiratory resistor and the combined inspiratory and expiratory resistor. Regression analysis of SPV or PPV versus DeltaSV showed the highest R2 (0.83 for SPV and 0.52 for PPV) when the expiratory resistor was applied. The corresponding sensitivity and specificity for prediction of fluid responsiveness were 100% and 100%, respectively, for SPV and 100% and 81%, respectively, for PPV. Inspiratory and/or expiratory threshold resistors magnified SPV and PPV in spontaneously breathing pigs during hypovolemia

  14. [APPLICATION OF NEGATIVE PRESSURE THERAPY].

    Science.gov (United States)

    Laginja, S; Marinović, M

    2016-01-01

    Negative pressure therapy is gradually taking an increasingly important role in the treatment of chronic wound healing because of its simple application in hospital or outpatient setting and good comfort with no pain for the patient. Chronic wound healing is accelerated in comparison with other conservative treatments. The level of negative pressure is between 40 and 125 mm Hg below ambient. Direct and indirect effect of the negative pressure therapy helps in wound healing and provides good preparation for definitive surgical management of wounds.

  15. Nebulized hypertonic saline via positive expiratory pressure versus via jet nebulizer in patients with severe cystic fibrosis.

    LENUS (Irish Health Repository)

    O'Connell, Oisin J

    2011-06-01

    Nebulized hypertonic saline is a highly effective therapy for patients with cystic fibrosis (CF), yet 10% of patients are intolerant of hypertonic saline administered via jet nebulizer. Positive expiratory pressure (PEP) nebulizers splint open the airways and offers a more controlled rate of nebulization.

  16. Improvement of lung mechanics by exogenous surfactant: effect of prior application of high positive end-expiratory pressure

    NARCIS (Netherlands)

    A. Hartog (Anneke); D.A.M.P.J. Gommers (Diederik); J.J. Haitsma (Jack); B.F. Lachmann (Burkhard)

    2000-01-01

    textabstractThe use of a ventilation strategy with high positive end-expiratory pressure (PEEP) that is intended to recruit collapsed alveoli and to prevent recurrent collapse can reduce alveolar protein influx in experimental acute lung injury (ALI). This could affect

  17. Positive end-expiratory pressure improves survival in a rodent model of cardiopulmonary resuscitation using high-dose epinephrine.

    LENUS (Irish Health Repository)

    McCaul, Conán

    2009-10-01

    Multiple interventions have been tested in models of cardiopulmonary resuscitation (CPR) to optimize drug use, chest compressions, and ventilation. None has studied the effects of positive end-expiratory pressure (PEEP) on outcome. We hypothesized that because PEEP can reverse pulmonary atelectasis, lower pulmonary vascular resistance, and potentially improve cardiac output, its use during CPR would increase survival.

  18. Dangerous Pressurization and Inappropriate Alarms during Water Occlusion of the Expiratory Circuit of Commonly Used Infant Ventilators.

    Directory of Open Access Journals (Sweden)

    Murray Hinder

    Full Text Available Non-invasive continuous positive airways pressure is commonly a primary respiratory therapy delivered via multi-purpose ventilators in premature newborns. Expiratory limb occlusion due to water accumulation or 'rainout' from gas humidification is a frequent issue. A case of expiratory limb occlusion due to rainout causing unexpected and excessive repetitive airway pressurisation in a Draeger VN500 prompted a systematic bench test examination of currently available ventilators.To assess neonatal ventilator response to partial or complete expiratory limb occlusion when set to non-invasive continuous positive airway pressure mode.Seven commercially available neonatal ventilators connected to a test lung using a standard infant humidifier circuit with partial and/or complete expiratory limb occlusion were examined in a bench test study. Each ventilator was set to deliver 6 cmH2O in non-invasive mode and respiratory mechanics data for 75%, 80% and 100% occlusion were collected.Several ventilators responded inappropriately with complete occlusion by cyclical pressurisation/depressurisation to peak pressures of between 19·4 and 64·6 cm H2O at rates varying between 2 to 77 inflations per minute. Tidal volumes varied between 10·1 and 24·3mL. Alarm responses varied from 'specific' (tube occluded to 'ambiguous' (Safety valve open. Carefusion Avea responded by continuing to provide the set distending pressure and displaying an appropriate alarm message. Draeger Babylog 8000 did not alarm with partial occlusions and incorrectly displayed airways pressure at 6·1cmH2O compared to the measured values of 13cmH2O.This study found a potential for significant adverse ventilator response due to complete or near complete expiratory limb occlusion in CPAP mode.

  19. Unintentional variation in positive end expiratory pressure during resuscitation with a T-piece resuscitator.

    Science.gov (United States)

    Finer, Neil N; Rich, Wade D

    2011-06-01

    The ability of T-piece resuscitators to deliver consistent peak inspiratory pressure (PIP) and positive end expiratory pressure (PEEP) during real and simulated neonatal resuscitation has been well described. The Neopuff (Fisher & Paykel Healthcare, Auckland, New Zealand) has been the device used for nearly all of these comparisons. All high risk resuscitations were carried out in our dedicated resuscitation room, and were recorded on video tape for quality assurance purposes.(1) In addition to the audio and video recording, physiologic signals and resuscitation parameters, including oxygen saturation, pulse rate, airway pressure, FiO(2), and others signals as appropriate were also captured. These recordings were reviewed on a biweekly basis as part of a continuing quality review process. Resuscitations were graded for standard of care and the resuscitation checklist was reviewed to determine if the team had any unresolved issues that needed to be addressed. In the year between April of 2009 and March 2010, a period when we fully reviewed approximately 120 videos, we recognized visually obvious PEEP changes on 8 different occasions in ELBW infants. Our target PEEP was 5 cm H20. We observed rapid changes in the PEEP to as high as 15 cm H20 during resuscitation. Based on our single-center experience, a T-piece resuscitation device which has the adjustment for the PEEP level and the orifice which is occluded to deliver a breath in the same location has the potential to cause an inadvertent and potentially toxic increase of PEEP which might not be noticed by the operator. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. Short hypobaric hypoxia and breathing pattern: effect of positive end expiratory pressure.

    Science.gov (United States)

    Savourey, G; Besnard, Y; Launay, J C; Guinet, A; Hanniquet, A M; Caterini, R; Bittel, J

    1999-09-01

    The ventilatory effects of a 5-cm H2O positive end expiratory pressure (PEEP) and its influence on the breathing pattern during short hypoxic exposure both at rest and during physical exercise were studied. There were 22 healthy subjects who were submitted to normoxia and to 4-h of hypoxia in a hypobaric chamber (4500 m, PB = 589 hPa) both at rest and during an 8-min cycle ergometer exercise (100 W) without and with a 5 cm H2O PEEP. The results show that hypoxia compared with normoxia induces increases in tidal volume (VT) (+28.5%, p breathing pattern expressed as duty cycle (tI/tt) is unchanged, whereas an increased mean inspiratory flow (VT/tI) is observed (p hypoxia significantly increases VT (+22.2% p breathing pattern in hypoxia since VT/tI and tI/tt are unchanged. Heart rate and arterial O2 saturation are also unaffected by PEEP. In conclusion, this study shows that a 4-h hypoxia modifies ventilatory parameters and mean inspiratory flow (VT/tI) at rest and during exercise (100 W), whereas a 5-cm H2O PEEP does not alter the breathing pattern despite changes in ventilatory parameters are observed.

  1. [A comparative study between inflation and deflation pressure-volume curve in determining the optimal positive end-expiratory pressure].

    Science.gov (United States)

    Gang, Li; Sun, Xiao-yi; Xu, Jin-quan; Zhang, Xin-li; Kou, Lu-xin; Jiang, Zhi-hong; Zhang, Lei

    2012-02-01

    To determine the optimal positive end-expiratory pressure (PEEP) according to inflation and deflation pressure-volume curve (P-V curve) in patients with acute respiratory distress syndrome (ARDS). ARDS models were reproduced in 20 dogs, and they were randomly divided into two groups. In both groups, Levenberg-Marquardt iterative algorithm was employed using software to explore parameters fitting with Boltzmann formula, by which the real inflection point of pressure (Pinf d) in deflation limb or lower inflection point pressure (PLip) in inflation limb on P-V curve were defined. For the control group (inflation curve) P-V curve of PLip + 2 cm H(2)O [1 cm H(2)O = 0.098 kPa] was applied as the best PEEP value. In the experimental group (deflation curve) the Pinf d was taken as the best PEEP value. The heart rate (HR), blood pressure (BP), fingertip pulse oxygen saturation [SpO(2)], static lung compliance (Cst), arterial partial pressure of oxygen [PaO(2)] and arterial partial pressure of carbon dioxide [PaCO(2)] were monitored at 0, 2, 6, 12, 24 and 48 hours. Oxygenation index increased significantly both in control and experimental groups. In experimental group, oxygenation index (mm Hg, 1 mm Hg = 0.133 kPa) of 12, 24 and 48 hours was respectively significantly higher than that of the control group (12 hours: 177.63 ± 8.94 vs. 165.60 ± 8.90, 24 hours: 194.19 ± 10.67 vs. 168.70 ± 10.60, 48 hours: 203.15 ± 13.21 vs. 171.26 ± 9.21, all P deflation P-V curve was better than that of inflation curve.

  2. Positive expiratory pressure improves oxygenation in healthy subjects exposed to hypoxia.

    Directory of Open Access Journals (Sweden)

    Hugo Nespoulet

    Full Text Available INTRODUCTION: Positive end-expiratory pressure (PEEP is commonly used in critical care medicine to improve gas exchange. Altitude sickness is associated with exaggerated reduction in arterial oxygenation. We assessed the effect of PEEP and pursed lips breathing (PLB on arterial and tissue oxygenation under normobaric and hypobaric hypoxic conditions. METHODS: Sixteen healthy volunteers were exposed to acute normobaric hypoxia (Laboratory study, FiO₂=0.12. The protocol consisted in 3-min phases with PEEPs of 0, 5 or 10 cmH₂O, PLB or similar ventilation than with PEEP-10, interspaced with 3-min phases of free breathing. Arterial (pulse oximetry and quadriceps (near-infrared spectroscopy oxygenation, ventilation, cardiac function, esophageal and gastric pressures and subjects' subjective perceptions were recorded continuously. In addition, the effect of PEEP on arterial oxygenation was tested at 4,350 m of altitude in 9 volunteers breathing for 20 min with PEEP-10 (Field study. RESULTS: During the laboratory study, PEEP-10 increased arterial and quadriceps oxygenation (arterial oxygen saturation +5.6±5.0% and quadriceps oxyhemoglobin +58±73 µmol.cm compared to free breathing; p0.05 compared to PEEP-0. During the field study, PEEP-10 increased arterial oxygen saturation by +6.7±6.0% after the 3(rd minute with PEEP-10 without further significant increase until the 20(th minute with PEEP-10. Subjects did not report any significant discomfort with PEEP. CONCLUSIONS: These data indicate that 10-cmH₂O PEEP significantly improves arterial and muscle oxygenation under both normobaric and hypobaric hypoxic conditions in healthy subjects. PEEP-10 could be an attractive non-pharmacological tool to limit blood oxygen desaturation and possibly symptoms at altitude.

  3. Positive expiratory pressure improves oxygenation in healthy subjects exposed to hypoxia.

    Science.gov (United States)

    Nespoulet, Hugo; Rupp, Thomas; Bachasson, Damien; Tamisier, Renaud; Wuyam, Bernard; Lévy, Patrick; Verges, Samuel

    2013-01-01

    Positive end-expiratory pressure (PEEP) is commonly used in critical care medicine to improve gas exchange. Altitude sickness is associated with exaggerated reduction in arterial oxygenation. We assessed the effect of PEEP and pursed lips breathing (PLB) on arterial and tissue oxygenation under normobaric and hypobaric hypoxic conditions. Sixteen healthy volunteers were exposed to acute normobaric hypoxia (Laboratory study, FiO₂=0.12). The protocol consisted in 3-min phases with PEEPs of 0, 5 or 10 cmH₂O, PLB or similar ventilation than with PEEP-10, interspaced with 3-min phases of free breathing. Arterial (pulse oximetry) and quadriceps (near-infrared spectroscopy) oxygenation, ventilation, cardiac function, esophageal and gastric pressures and subjects' subjective perceptions were recorded continuously. In addition, the effect of PEEP on arterial oxygenation was tested at 4,350 m of altitude in 9 volunteers breathing for 20 min with PEEP-10 (Field study). During the laboratory study, PEEP-10 increased arterial and quadriceps oxygenation (arterial oxygen saturation +5.6±5.0% and quadriceps oxyhemoglobin +58±73 µmol.cm compared to free breathing; pbreathing pattern, end-tidal CO₂ or cardiac function (all p>0.05) compared to PEEP-0. During the field study, PEEP-10 increased arterial oxygen saturation by +6.7±6.0% after the 3(rd) minute with PEEP-10 without further significant increase until the 20(th) minute with PEEP-10. Subjects did not report any significant discomfort with PEEP. These data indicate that 10-cmH₂O PEEP significantly improves arterial and muscle oxygenation under both normobaric and hypobaric hypoxic conditions in healthy subjects. PEEP-10 could be an attractive non-pharmacological tool to limit blood oxygen desaturation and possibly symptoms at altitude.

  4. Positive end-expiratory pressure improves gas exchange and pulmonary mechanics during partial liquid ventilation.

    Science.gov (United States)

    Kirmse, M; Fujino, Y; Hess, D; Kacmarek, R M

    1998-11-01

    Partial liquid ventilation (PLV) with perflubron (PFB) has been proposed as an adjunct to the current therapies for the acute respiratory distress syndrome (ARDS). Because PFB has been also referred to as "liquid PEEP," distributing to the most gravity-dependent regions of the lung, less attention has been paid to the amount of applied positive end-expiratory pressure (PEEP). We hypothesized that higher PEEP levels than currently applied are needed to optimize gas exchange, and that the lower inflection point (LIP) of the pressure-volume curve could be used to estimate the amount of PEEP needed when the lung is filled with PFB. Lung injury was induced in 23 sheep by repeated lung lavage with warmed saline until the PaO2/FIO2 ratio fell below 150. Five sheep were used to investigate the change of the LIP when the lung was filled with PFB in increments of 5 ml/kg/body weight to a total of 30 ml/kg/body weight. To evaluate the impact of PEEP set at LIP +1 cm H2O we randomized an additional 15 sheep to three groups with different doses (7.5 ml, 15 ml, 30 ml/kg/body weight) of PFB. In random order a PEEP of 5 cm H2O or PEEP at LIP +1 cm H2O was applied. The LIP decreased with incremental filling of PFB to a minimum at 10 ml (p PFB shifts the LIP to the left, and that setting PEEP at LIP +1 cm H2O improves gas exchange at moderate to high doses of PFB.

  5. Incisional Negative Pressure Wound Therapy

    DEFF Research Database (Denmark)

    Hyldig, Nana; Birke-Sorensen, Hanne; Kruse, Marie

    Aim: Postoperative wound complications make many surgical procedures unnecessarily complex, particularly in high-risk patients. Negative Pressure Wound Therapy is well recognized in the management of open wounds. In recent years, it has been introduced as well in the management of closed surgical...... incisions to reduce postoperative wound complications, though the evidence base to support this intervention is limited. The aim of this study was to assess if Negative Pressure Wound Therapy (NPWT) reduces postoperative complications when applied on closed surgical incisions. Method: A systematic review...

  6. Effects of positive end-expiratory pressure and recruitment maneuvers in a ventilator-induced injury mouse model.

    Science.gov (United States)

    Cagle, Laura A; Franzi, Lisa M; Linderholm, Angela L; Last, Jerold A; Adams, Jason Y; Harper, Richart W; Kenyon, Nicholas J

    2017-01-01

    Positive-pressure mechanical ventilation is an essential therapeutic intervention, yet it causes the clinical syndrome known as ventilator-induced lung injury. Various lung protective mechanical ventilation strategies have attempted to reduce or prevent ventilator-induced lung injury but few modalities have proven effective. A model that isolates the contribution of mechanical ventilation on the development of acute lung injury is needed to better understand biologic mechanisms that lead to ventilator-induced lung injury. To evaluate the effects of positive end-expiratory pressure and recruitment maneuvers in reducing lung injury in a ventilator-induced lung injury murine model in short- and longer-term ventilation. 5-12 week-old female BALB/c mice (n = 85) were anesthetized, placed on mechanical ventilation for either 2 hrs or 4 hrs with either low tidal volume (8 ml/kg) or high tidal volume (15 ml/kg) with or without positive end-expiratory pressure and recruitment maneuvers. Alteration of the alveolar-capillary barrier was noted at 2 hrs of high tidal volume ventilation. Standardized histology scores, influx of bronchoalveolar lavage albumin, proinflammatory cytokines, and absolute neutrophils were significantly higher in the high-tidal volume ventilation group at 4 hours of ventilation. Application of positive end-expiratory pressure resulted in significantly decreased standardized histology scores and bronchoalveolar absolute neutrophil counts at low- and high-tidal volume ventilation, respectively. Recruitment maneuvers were essential to maintain pulmonary compliance at both 2 and 4 hrs of ventilation. Signs of ventilator-induced lung injury are evident soon after high tidal volume ventilation (as early as 2 hours) and lung injury worsens with longer-term ventilation (4 hrs). Application of positive end-expiratory pressure and recruitment maneuvers are protective against worsening VILI across all time points. Dynamic compliance can be used guide the frequency

  7. Effects of positive end-expiratory pressure and recruitment maneuvers in a ventilator-induced injury mouse model.

    Directory of Open Access Journals (Sweden)

    Laura A Cagle

    Full Text Available Positive-pressure mechanical ventilation is an essential therapeutic intervention, yet it causes the clinical syndrome known as ventilator-induced lung injury. Various lung protective mechanical ventilation strategies have attempted to reduce or prevent ventilator-induced lung injury but few modalities have proven effective. A model that isolates the contribution of mechanical ventilation on the development of acute lung injury is needed to better understand biologic mechanisms that lead to ventilator-induced lung injury.To evaluate the effects of positive end-expiratory pressure and recruitment maneuvers in reducing lung injury in a ventilator-induced lung injury murine model in short- and longer-term ventilation.5-12 week-old female BALB/c mice (n = 85 were anesthetized, placed on mechanical ventilation for either 2 hrs or 4 hrs with either low tidal volume (8 ml/kg or high tidal volume (15 ml/kg with or without positive end-expiratory pressure and recruitment maneuvers.Alteration of the alveolar-capillary barrier was noted at 2 hrs of high tidal volume ventilation. Standardized histology scores, influx of bronchoalveolar lavage albumin, proinflammatory cytokines, and absolute neutrophils were significantly higher in the high-tidal volume ventilation group at 4 hours of ventilation. Application of positive end-expiratory pressure resulted in significantly decreased standardized histology scores and bronchoalveolar absolute neutrophil counts at low- and high-tidal volume ventilation, respectively. Recruitment maneuvers were essential to maintain pulmonary compliance at both 2 and 4 hrs of ventilation.Signs of ventilator-induced lung injury are evident soon after high tidal volume ventilation (as early as 2 hours and lung injury worsens with longer-term ventilation (4 hrs. Application of positive end-expiratory pressure and recruitment maneuvers are protective against worsening VILI across all time points. Dynamic compliance can be used guide

  8. Estimation of tracheal pressure and imposed expiratory work of breathing by the endotracheal tube, heat and moisture exchanger, and ventilator during mechanical ventilation.

    Science.gov (United States)

    Uchiyama, Akinori; Yoshida, Takeshi; Yamanaka, Hidenori; Fujino, Yuji

    2013-07-01

    The resistance of the endotracheal tube (ETT), the heat and moisture exchanger (HME), and the ventilator may affect the patient's respiratory status. Although previous studies examined the inspiratory work of breathing (WOB), investigation of WOB in the expiratory phase is rare. We estimated tracheal pressure at the tip of the ETT (Ptrach) and calculated expiratory WOB imposed by the ETT, the HME, and the expiratory valve. We examined imposed expiratory WOB in patients under a continuous mandatory ventilation (CMV) mode and during spontaneous breathing trials (SBTs). We hypothesized that imposed expiratory WOB would increase with heightened ventilatory demand. We measured airway pressure (Paw) and respiratory flow (V). We estimated Ptrach using the equation Ptrach = Paw - K1 × V(K2) - 2.70 × V(L/s)(1.42). K1 and K2 were determined by the inner diameter (ID) of the ETT. Imposed expiratory WOB was calculated from the area of Ptrach above PEEP versus lung volume. We examined imposed expiratory WOB and imposed expiratory resistance in relation to mean expiratory flow. We examined 28 patients under CMV mode, and 29 during SBT. During both CMV and SBT, as mean expiratory flow increased, imposed expiratory WOB increased. The regression curves between mean expiratory flow (x) (L/s) and imposed expiratory WOB (y) (J/L) were y = 1.35x(0.83) (R(2) = 0.79) for 7 mm ID ETT under CMV, y = 1.12x(0.82) (R(2) = 0.73) for 8 mm ID ETT under CMV, y = 1.07x(1.04) (R(2) = 0.85) for 7 mm ID ETT during SBT, and y = 0.84x(0.93) (R(2) = 0.75) for 8 mm ID ETT during SBT. Levels of imposed expiratory WOB were affected by ETT diameter and ventilator mode. The reason for increasing imposed expiratory WOB was an increase in expiratory resistance imposed by the ETT and HME. Under mechanical ventilation, imposed expiratory WOB should be considered in patients with higher minute ventilation.

  9. Pulmonary acute respiratory distress syndrome: positive end-expiratory pressure titration needs stress index.

    Science.gov (United States)

    Huang, Yingzi; Yang, Yi; Chen, Qiuhua; Liu, Songqiao; Liu, Ling; Pan, Chun; Yang, Congshan; Qiu, Haibo

    2013-11-01

    The heterogeneity of lung injury in pulmonary acute respiratory distress syndrome (ARDS) may have contributed to the greater response of hyperinflated area with positive end-expiratory pressure (PEEP). PEEP titrated by stress index can reduce the risk of alveolar hyperinflation in patients with pulmonary ARDS. The authors sought to investigate the effects of PEEP titrated by stress index on lung recruitment and protection after recruitment maneuver (RM) in pulmonary ARDS patients. Thirty patients with pulmonary ARDS were enrolled. After RM, PEEP was randomly set according to stress index, oxygenation, static pulmonary compliance (Cst), or lower inflection point (LIP) + 2 cmH2O strategies. Recruitment volume, gas exchange, respiratory mechanics, and hemodynamic parameters were collected. PEEP titrated by stress index (15.1 ± 1.8 cmH2O) was similar to the levels titrated by oxygenation (14.5 ± 2.9 cmH2O), higher than that titrated by Cst (11.3 ± 2.5 cmH2O) and LIP (12.9 ± 1.6 cmH2O) (P stress index and oxygenation but higher than that titrated by Cst and LIP. Compared with baseline, lung compliance increased significantly when PEEP determined by Cst, but there was no difference of Cst in these four strategies. There was no influence of PEEP titration with the four strategies on hemodynamic parameters. PEEP titration by stress index might be more beneficial for pulmonary ARDS patients after RM. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Nasal Expiratory Positive Airway Pressure Devices (Provent for OSA: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Muhammad Riaz

    2015-01-01

    Full Text Available Objective. To quantify the effectiveness of nasal expiratory positive airway pressure (nasal EPAP devices or Provent as treatment for obstructive sleep apnea (OSA. Methods. PubMed and six other databases were searched through November 15, 2015, without language limitations. Results. Eighteen studies (920 patients were included. Pre- and post-nasal EPAP means ± standard deviations (M ± SD for apnea-hypopnea index (AHI in 345 patients decreased from 27.32±22.24 to 12.78±16.89 events/hr (relative reduction = 53.2%. Random effects modeling mean difference (MD was −14.78 events/hr [95% CI −19.12, −10.45], p value < 0.00001. Oxygen desaturation index (ODI in 247 patients decreased from 21.2±19.3 to 12.4±14.1 events/hr (relative reduction = 41.5%, p value < 0.00001. Lowest oxygen saturation (LSAT M ± SD improved in 146 patients from 83.2±6.8% to 86.2±11.1%, MD 3 oxygen saturation points [95% CI 0.57, 5.63]. Epworth Sleepiness Scale (ESS M ± SD improved (359 patients from 9.9±5.3 to 7.4±5.0, MD −2.5 [95% CI −3.2, −1.8], p value < 0.0001. Conclusion. Nasal EPAP (Provent reduced AHI by 53.2%, ODI by 41.5% and improved LSAT by 3 oxygen saturation points. Generally, there were no clear characteristics (demographic factors, medical history, and/or physical exam finding that predicted favorable response to these devices. However, limited evidence suggests that high nasal resistance could be associated with treatment failure. Additional studies are needed to identify demographic and polysomnographic characteristics that would predict therapeutic success with nasal EPAP (Provent.

  11. Negative-Pressure Pulmonary Edema.

    Science.gov (United States)

    Bhattacharya, Mallar; Kallet, Richard H; Ware, Lorraine B; Matthay, Michael A

    2016-10-01

    Negative-pressure pulmonary edema (NPPE) or postobstructive pulmonary edema is a well-described cause of acute respiratory failure that occurs after intense inspiratory effort against an obstructed airway, usually from upper airway infection, tumor, or laryngospasm. Patients with NPPE generate very negative airway pressures, which augment transvascular fluid filtration and precipitate interstitial and alveolar edema. Pulmonary edema fluid collected from most patients with NPPE has a low protein concentration, suggesting hydrostatic forces as the primary mechanism for the pathogenesis of NPPE. Supportive care should be directed at relieving the upper airway obstruction by endotracheal intubation or cricothyroidotomy, institution of lung-protective positive-pressure ventilation, and diuresis unless the patient is in shock. Resolution of the pulmonary edema is usually rapid, in part because alveolar fluid clearance mechanisms are intact. In this review, we discuss the clinical presentation, pathophysiology, and management of negative-pressure or postobstructive pulmonary edema. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  12. [Clinical research of using optimal compliance to determine positive end-expiratory pressure].

    Science.gov (United States)

    Xu, Lei; Feng, Quan-sheng; Lian, Fu; Shao, Xin-hua; Li, Zhi-bo; Wang, Zhi-yong; Li, Jun

    2012-07-01

    To observe the availability and security of optimal compliance strategy to titrate the optimal positive end-expiratory pressure (PEEP), compared with quasi-static pressure-volume curve (P-V curve) traced by low-flow method. Fourteen patients received mechanical ventilation with acute respiratory distress syndrome (ARDS) admitted in intensive care unit (ICU) of Tianjin Third Central Hospital from November 2009 to December 2010 were divided into two groups(n = 7). The quasi-static P-V curve method and the optimal compliance titration were used to set the optimal PEEP respectively, repeated 3 times in a row. The optimal PEEP and the consistency of repeated experiments were compared between groups. The hemodynamic parameters, oxygenation index (OI), lung compliance (C), cytokines and pulmonary surfactant-associated protein D (SP-D) concentration in plasma before and 2, 4, and 6 hours after the experiment were observed in each group. (1) There were no significant differences in gender, age and severity of disease between two groups. (2)The optimal PEEP [cm H(2)O, 1 cm H(2)O=0.098 kPa] had no significant difference between quasi-static P-V curve method group and the optimal compliance titration group (11.53 ± 2.07 vs. 10.57 ± 0.87, P>0.05). The consistency of repeated experiments in quasi-static P-V curve method group was poor, the slope of the quasi-static P-V curve in repeated experiments showed downward tendency. The optimal PEEP was increasing in each measure. There was significant difference between the first and the third time (10.00 ± 1.58 vs. 12.80 ± 1.92, P vs. 93.71 ± 5.38, temperature: 38.05 ± 0.73 vs. 36.99 ± 1.02, IL-6: 144.84 ± 23.89 vs. 94.73 ± 5.91, TNF-α: 151.46 ± 46.00 vs. 89.86 ± 13.13, SP-D: 33.65 ± 8.66 vs. 16.63 ± 5.61, MAP: 85.47 ± 9.24 vs. 102.43 ± 8.38, CCI: 3.00 ± 0.48 vs. 3.81 ± 0.81, OI: 62.00 ± 21.45 vs. 103.40 ± 37.27, C: 32.10 ± 2.92 vs. 49.57 ± 7.18, all P safety and usability.

  13. Validation of a protocol to evaluate maximal expiratory pressure using a pressure transducer and a signal conditioner

    Directory of Open Access Journals (Sweden)

    Viviane Soares

    2011-09-01

    Full Text Available The respiratory muscles can present fatigue and even chronic inability to generate force. So, reliable devices are necessary to their evaluation. The aim of this study is to evaluate the MEP (Maximal Expiratory Pressure values of individuals between 20 and 25 years old and to validate a protocol using a pressure transducer and a signal conditioner comparing it with the digital manometer. We evaluated the MEP of 10 participants. They remained seated and made six respiratory maneuvers from Total Lung Capacity (TLC to Residual Volume (RV. The results in the study showed no statistically significant differences when compared to values reported in the literature, and that the pressure transducer provides reliable values for MEP.Os músculos respiratórios podem apresentar fadiga e até mesmo a incapacidade crônica na geração de força, sendo necessários dispositivos confiáveis para sua avaliação. O objetivo deste estudo foi avaliar a pressão expiratória máxima (PeMáx de indivíduos entre 20 e 25 anos e validar um protocolo que utiliza um transdutor de pressão e um condicionador de sinais comparando-o com a manovacuometria. Foram avaliadas a PeMáx de 10 participantes. Estes permaneceram sentados e realizaram seis manobras respiratórias a partir da capacidade pulmonar total (CPT até o volume residual (VR. Os resultados do estudo não apresentaram diferenças estatisticamente significativas quando comparados com os valores de normalidade descritos na literatura e mostraram que o transdutor de pressão fornece valores confiáveis para Pe máx.

  14. Protective intraoperative ventilation with higher versus lower levels of positive end-expiratory pressure in obese patients (PROBESE): study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Bluth, T.; Teichmann, R.; Kiss, T.; Bobek, I.; Canet, J.; Cinnella, G.; de Baerdemaeker, L.; Gregoretti, C.; Hedenstierna, G.; Hemmes, S. N.; Hiesmayr, M.; Hollmann, M. W.; Jaber, S.; Laffey, J. G.; Licker, M. J.; Markstaller, K.; Matot, I.; Müller, G.; Mills, G. H.; Mulier, J. P.; Putensen, C.; Rossaint, R.; Schmitt, J.; Senturk, M.; Serpa Neto, A.; Severgnini, P.; Sprung, J.; Vidal Melo, M. F.; Wrigge, H.; Schultz, M. J.; Pelosi, P.; Gama de Abreu, M.; Güldner, Andreas; Huhle, Robert; Uhlig, Christopher; Vivona, Luigi; Bergamaschi, Alice; Rossaint, Rolf; Stevanovic, Ana; Treschan, Tanja; Schaefer, Maximilian; Kienbaum, Peter; Laufenberg-Feldmann, Rita; Bergmann, Lars; Ebner, Felix; Robitzky, Luisa; Mölders, Patrick; Unterberg, Matthias; Busch, Cornelius; Achilles, Marc; Menzen, Angelika; Freesemann, Harbert; Putensen, Christian; Machado, Humberto; Cavaleiro, Carla; Ferreira, Cristina; Pinho, Daniela; Carvalho, Marta; Pinho, Sílvia; Soares, Maria; Castro, Diogo Sousa; Abelha, Fernando; Rabico, Rui; Delphin, Ellise; Sprung, Juraj; Weingarten, Toby N.; Kellogg, Todd A.; Martin, Yvette N.; McKenzie, Travis J.; Brull, Sorin J.; Renew, J. Ross; Ramakrishna, Harish; Fernandez-Bustamante, Ana; Balonov, Konstantin; Baig, Harris R.; Kacha, Aalok; Pedemonte, Juan C.; Altermatt, Fernando; Corvetto, Marcia A.; Paredes, Sebastian; Carmona, Javiera; Rolle, Augusto; Bos, Elke; Beurskens, Charlotte; Veering, B.; Zonneveldt, Harry; Boer, Christa; Godfried, Marc; Thiel, Bram; Kabon, Barbara; Reiterer, Christian; Canet, Jaume; Tolós, Raquel; Sendra, Mar; González, Miriam; Gómez, Noemí; Ferrando, Carlos; Socorro, Tania; Izquierdo, Ana; Soro, Marina; Granell Gil, Manuel; Hernández Cádiz, María José; Biosca Pérez, Elena; Suarez-de-la-Rica, Alejandro; Lopez-Martinez, Mercedes; Huercio, Iván; Maseda, Emilio; Yagüe, Julio; Cebrian Moreno, Alba; Rivas, Eva; Lopez-Baamonde, Manuel; Elgendy, Hamed; Sayedalahl, Mohamed; SIibai, Abdul Razak; Yavru, Aysen; Sivrikoz, Nukhet; Karadeniz, Meltem; Corman Dincer, Pelin; Ayanoglu, Hilmi Omer; Tore Altun, Gulbin; Kavas, Ayse Duygu; Dinc, Bora; Kuvaki, Bahar; Ozbilgin, Sule; Erdogan, Dilek; Koksal, Ceren; Abitagaglu, Suheyla; Aurilio, Caterina; Sansone, Pasquale; Pace, Caterina Maria; Donatiello, Valerio; Mattera, Silvana; Nazareno, Palange; Di Colandrea, Salvatore; Spadaro, Savino; Volta, Carlo Alberto; Ragazzi, Riccardo; Ciardo, Stefano; Gobbi, Luca; Severgnini, Paolo; Bacuzzi, Alessandro; Brugnoni, Elisa; Gratarola, Angelo; Micalizzi, Camilla; Simonassi, Francesca; Malerbi, Patrizia; Carboni, Adrea; Licker, Marc-Joseph; Dullenkopf, Alexander; Goettel, Nicolai; Nesek Adam, Visnja; Karaman Ilić, Maja; Klaric, Vlasta; Vitkovic, Bibiana; Milic, Morena; Miro, Zupcic; de Baerdemaeker, Luc; de Hert, Stefan; Heyse, Bjorn; van Limmen, Jurgen; van Nieuwenhove, Yves; Mertens, Els; Neyrinck, Arne; Mulier, Jan; Kahn, David; Godoroja, Daniela; Martin-Loeches, Martin; Vorotyntsev, Sergiy; Fronchko, Valentyna; Matot, Idit; Goren, Or; Zac, Lilach; Gaszynski, Thomasz; Laffey, Jon; Mills, Gary; Nalwaya, Pramod; Mac Gregor, Mark; Paddle, Jonathan; Balaji, Packianathaswamy; Rubulotta, Francesca; Adebesin, Afeez; Margarson, Mike; Davies, Simon; Rangarajan, Desikan; Newell, Christopher; Shosholcheva, Mirjana; Papaspyros, Fotios; Skandalou, Vasiliki; Dzurňáková, Paula

    2017-01-01

    Background: Postoperative pulmonary complications (PPCs) increase the morbidity and mortality of surgery in obese patients. High levels of positive end-expiratory pressure (PEEP) with lung recruitment maneuvers may improve intraoperative respiratory function, but they can also compromise

  15. Comparison of intermittent positive pressure breathing and temporary positive expiratory pressure in patients with severe chronic obstructive pulmonary disease.

    Science.gov (United States)

    Nicolini, Antonello; Mollar, Elena; Grecchi, Bruna; Landucci, Norma

    2014-01-01

    Results supporting the use and the effectiveness of positive expiratory, pressure devices in chronic obstructive pulmonary disease (COPD) patients are still controversial, We have tested the hypothesis that adding TPEP or IPPB to standard pharmacological therapy may provide additional clinical benefit over, pharmacological therapy only in patients with severe COPD. Fourty-five patients were randomized in three groups: a group was treated; with IPPB,a group was treated with TPEP and a group with pharmacological; therapy alone (control group). Primary outcome measures included the measurement of scale or, questionnaire concerning dyspnea (MRC scale),dyspnea,cough, and, sputum (BCSS) and quality of life (COPD assessment test) (CAT). Secondary, outcome measures were respiratory function testing,arterial blood gas,analysis,and hematological examinations. Both patients in the IPPB group and in the TPEP group showed a significant, improvement in two of three tests (MRC,CAT) compared to the control, group.However,in the group comparison analysis for, the same variables between IPPB group and TPEP group we observed a, significant improvement in the IPPB group (P≤.05 for MRC and P≤.01 for, CAT). The difference of action of the two techniques are evident in the results of, pulmonary function testing: IPPB increases FVC, FEV1, and MIP; this reflects, its capacity to increase lung volume. Also TPEP increases FVC and FEV1 (less, than IPPB), but increases MEP, while decreasing total lung capacity and, residual volume. The two techniques (IPPB and TPEP) improves significantly dyspnea; quality of; life tools and lung function in patients with severe COPD. IPPB demonstrated a greater effectiveness to improve dyspnea and quality of life tools (MRC, CAT) than TPEP. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

  16. Incisional Negative Pressure Wound Therapy

    DEFF Research Database (Denmark)

    Hyldig, Nana

    a randomised controlled trial in two tertiary and three teaching hospitals in three regions of Denmark, the Happy Belly Study, investigating the effectiveness of iNPWT in a population of obese women after caesarean section. The Happy Belly Study has demonstrated that prophylactic iNPWT significantly reduced......-risk population of obese women giving birth by caesarean section. The Happy Belly Study is ongoing and thus this thesis presents preliminary results based on data from the first two-thirds of the scheduled study participants. Nonetheless, the results in this thesis are convincing. Accordingly, i......Women with a pre-gestational body mass index (BMI) above 30 kg/m2 giving birth by caesarean section are at high risk of surgical wound infection compared with women with a BMI below 30 kg/m2. Incisional Negative Pressure Wound Therapy (iNPWT) is one strategy to reduce the rate of surgical wound...

  17. Positive end-expiratory pressure attenuates hemodynamic effects induced by an overload of inspiratory muscles in patients with COPD

    Directory of Open Access Journals (Sweden)

    Schaper-Magalhães F

    2017-10-01

    Full Text Available Flavia Schaper-Magalhães,1 José Felippe Pinho,1 Carolina Andrade Bragança Capuruço,2 Maria Glória Rodrigues-Machado1 1Medical Sciences Faculty of Minas Gerais, Post-Graduation Program in Health Sciences, Belo Horizonte, Brazil; 2Department of Cardiology, Clinics Hospital, Federal University of Minas Gerais, Belo Horizonte, Brazil Background: Inspiratory muscle training (IMT using a Threshold® device is commonly used to improve the strength and endurance of inspiratory muscles. However, the effect of IMT, alone or with positive end-expiratory pressure (PEEP, on hemodynamic parameters in patients with chronic obstructive pulmonary disease (COPD remains unknown.Objective: To assess the effects of an overload of inspiratory muscles using IMT fixed at 30% of the maximal inspiratory pressure (MIP, and IMT associated with 5 cmH2O of PEEP (IMT + PEEP, on the echocardiographic parameters in healthy subjects and patients with COPD.Methods: Twenty patients with COPD (forced expiratory volume in 1 second 53.19±24.71 pred% and 15 age-matched healthy volunteers were evaluated using spirometry, MIP, the COPD assessment test (CAT, and the modified Medical Research Council (mMRC dyspnea scale. The E- (fast-filling phase and A- (atrial contraction phase waves were evaluated at the tricuspid and mitral valves during inspiration and expiration in the following sequence: at basal conditions, using IMT, and using IMT + PEEP.Results: Patients with COPD had reduced MIPs versus the control group. Ten patients had CAT scores <10 and 12 patients had mMRC scores <2. E-wave values at the mitral valve were significantly decreased with IMT during the inspiratory phase in both groups. These effects were normalized with IMT + PEEP. During the expiratory phase, use of IMT + PEEP normalized the reduction in E-wave values in the COPD group. During inspiration at the tricuspid valve, reduction in E-wave values during IMT was normalized by IMT + PEEP in COPD group. During the

  18. [POSITIVE END-EXPIRATORY PRESSURE (PEEP) INFLUENCES ON INTRACRANIAL PRESSURE, SYSTEMIC HEMODYNAMICS AND PULMONARY GAS EXCHANGE IN PATIENTS WITH INTRACRANIAl HEMORRHAGE IN CRITICAL STATE].

    Science.gov (United States)

    Solodov, A A; Petrikov, S S; Krylov, V V

    2016-01-01

    Positive end-expiratory pressure is one of the main parameters of respiratory support influencing the gas exchange. However, despite the number ofpositive effects, PEEP can compromise venous outflow from the cranial cavity, increased intracranial pressure, decreased venous return and cardiac output and, consequently, reduced blood pressure and cerebral perfusion. The article presents the results of a survey of 39 patients with intracranial hemorrhage in critical state, undergoing respiratory support with different levels of positive end-expiratory pressure. Increasing of PEEP to 15 cm H2O had no adverse effect on mean arterial pressure, heart rate and cerebral perfusion pressure and led only to an clinical insignificant increase (maximum on 2.4 +/- 5.1 mmHg) in intracranial pressure. The greatest hemodynamic changes were observed with increasing PEEP up to 20 cm H2O in patients with preserved compliance ofthe respiratory system. The instability of cerebral perfusion and intracranial pressure associated with a decrease in cardiac output and preload and the exhaustion of compensatory mechanism of peripheral vascular resistance. High levels of PEEP despite the trend towards Cstat reduction will not lead to an increase in the content of extravascular lung water Thus a gradual increase of PEEP to 15 cm H2O can be safe and effective method of improving pulmonary gas exchange in patients with intracranial hemorrhage in critical state.

  19. Relationship between respiratory impedance and positive end-expiratory pressure in mechanically ventilated neonates.

    Science.gov (United States)

    Dellacà, Raffaele L; Veneroni, C; Vendettuoli, V; Zannin, E; Matassa, P G; Pedotti, A; Colnaghi, M; Mosca, F

    2013-03-01

    To evaluate the feasibility of forced oscillation technique (FOT) measurements at the bedside and to describe the relationship between positive end-expiration pressure (PEEP) and lung mechanics in different groups of ventilated infants. Twenty-eight infants were studied: 5 controls, 16 newborns with respiratory distress syndrome (RDS) and 7 chronically ventilated newborns that developed bronchopulmonary dysplasia. An incremental/decremental PEEP trial was performed by changing PEEP in 1-min steps of 1 cmH(2)O between 2 and 10 cmH(2)O. Forced oscillations at 5 Hz were superimposed on the ventilator waveform. Pressure and flow, measured at the inlet of the ETT, were used to compute resistance (Rrs) and reactance (Xrs). In controls Rrs and Xrs were on average 41 ± 21 and -22 ± 6 cmH(2)O s/l respectively and were almost unaffected by PEEP. RDS infants presented similar Rrs (48 ± 25 cmH(2)O s/l) and reduced Xrs (-71 ± 19 cmH(2)O s/l) at the beginning of the trial. Two behaviours were observed as PEEP was increased: in extremely low birth weight infants Xrs decreased with PEEP with marked hysteresis; in very low and low birth weight infants Xrs and Rrs were less PEEP dependent. Chronically ventilated infants had very high Rrs and very negative Xrs values at very low PEEPs (121 ± 41 and -95 ± 13 cmH(2)O s/l at PEEP = 2 cmH(2)O) that markedly changed as PEEP exceeded 3-4 cmH(2)O. Rrs and Xrs measurement in preterm newborns is feasible, and data are representative of the lung mechanics and very sensitive to its changes with PEEP, making FOT a promising technique for the non-invasive bedside titration of mechanical ventilation in preterm newborns.

  20. Limited predictability of maximal muscular pressure using the difference between peak airway pressure and positive end-expiratory pressure during proportional assist ventilation (PAV).

    Science.gov (United States)

    Su, Po-Lan; Kao, Pei-Shan; Lin, Wei-Chieh; Su, Pei-Fang; Chen, Chang-Wen

    2016-11-27

    If the proportional assist ventilation (PAV) level is known, muscular effort can be estimated from the difference between peak airway pressure and positive end-expiratory pressure (PEEP) (ΔP) during PAV. We conjectured that deducing muscle pressure from ΔP may be an interesting method to set PAV, and tested this hypothesis using the oesophageal pressure time product calculation. Eleven mechanically ventilated patients with oesophageal pressure monitoring under PAV were enrolled. Patients were randomly assigned to seven assist levels (20-80%, PAV20 means 20% PAV gain) for 15 min. Maximal muscular pressure calculated from oesophageal pressure (P mus, oes ) and from ΔP (P mus, aw ) and inspiratory pressure time product derived from oesophageal pressure (PTP oes ) and from ΔP (PTP aw ) were determined from the last minute of each level. P mus, oes and PTP oes with consideration of PEEPi were expressed as P mus, oes, PEEPi and PTP oes, PEEPi , respectively. Pressure time product was expressed as per minute (PTP oes , PTP oes, PEEPi , PTP aw ) and per breath (PTP oes, br , PTP oes, PEEPi, br , PTP aw, br ). PAV significantly reduced the breathing effort of patients with increasing PAV gain (PTP oes 214.3 ± 80.0 at PAV20 vs. 83.7 ± 49.3 cmH 2 O•s/min at PAV80, PTP oes, PEEPi 277.3 ± 96.4 at PAV20 vs. 121.4 ± 71.6 cmH 2 O•s/min at PAV80, p PAV and underestimates P mus, oes for moderate-gain to high-gain PAV. An optimal P mus, aw could be achieved in 91% of cases with PAV60. When the PAV gain was adjusted to P mus, aw of 5-10 cmH 2 O, there was a 93% probability of PTP oes PAV has limited accuracy. The extrapolated pressure time product from ΔP is usually less than the pressure time product calculated from oesophageal pressure tracing. However, when the PAV gain was adjusted to P mus, aw of 5-10 cmH 2 O, there was a 90% probability of PTP oes and PTP oes, PEEPi within acceptable ranges. This information should be considered when applying

  1. Effect of Supplementing Oxygen with Positive end Expiratory Pressure During Elective Caesarean Section under Spinal Anaesthesia on Foetus

    Science.gov (United States)

    Prabhu, Ramesh; Jayaraj; Shenoy, U Kailasanath

    2010-01-01

    Background: It is known fact that pre-oxygenation with positive end-expiratory pressure (PEEP) improves the Partial pressure of oxygen (PO 2). In this regard not many studies have been done in pregnant women to know its effect on foetus. In this randomised double blind controlled study, we analysed effect of pre-oxygenation with PEEP during caesarean section on foetal umbilical venous PO 2. Patients & Methods: 40 term pregnant women, ASA I or II, undergoing elective Caesarean section under spinal anaes-thesia were randomly divided into PEEP and Non-PEEP groups of 20 each. PEEP group received oxygen flow of 6 L/minute with PEEP of 5 cmH 2O using a modified Mapleson A circuit with fixed unidirectional PEEP valve at the expiratory port during pre-oxygenation and Non PEEP group received same fresh gas flow of oxygen using same breathing circuit without PEEP. Maternal arterial blood samples were collected before applying PEEP and at the end of 5 minutes of facemask application for oxygen analysis. Immediately after baby was delivered umbilical venous samples were taken for blood gas analysis. Results: Both groups were comparable in terms of maternal baseline oxygen saturation (Spo 2) and base line Po 2. After 5 minutes PO 2was higher in PEEP Group than non PEEP group (491.65 + 49.96 vs. 452.08 + 77.61). Umbilical venous Po 2in PEEP group was higher than non PEEP group (34.22 + 6.50 vs. 28.29 + 6.10 mm of Hg). Conclusion: Application of PEEP during pre-oxygenation for spinal anaesthesia can increase foetal umbilical venous PO2. PMID:21547172

  2. Effects of positive end-expiratory pressure and body position on pulmonary blood flow redistribution in mechanically ventilated normal pigs.

    Science.gov (United States)

    Richard, Jean-Christophe; Decailliot, Francois; Janier, Marc; Annat, Guy; Guérin, Claude

    2002-09-01

    To assess the respective effects of position and positive end-expiratory pressure (PEEP) on the distribution of regional pulmonary blood flow (PBF). Prospective randomized animal study. Animal research facility in a university hospital. Normal pigs that were tracheostomized, anesthetized, and mechanically ventilated. PBF was measured in seven pigs in the supine position (SP) and the prone position (PP) at both zero end-expiratory pressure (ZEEP) and 10 cm H(2)O of PEEP. The regional PBF was assessed by the radioactive microsphere method. The lungs from each pig were sliced into 90 samples. The heterogeneity of PBF was estimated from its coefficient of variation. The lung samples had a mean (+/- SD) weight of 1.60 +/- 0.39 g. Changing position from SP to PP at ZEEP redistributed PBF toward the anterior, superior, and peripheral regions and did not significantly reduce the coefficient of variation for regional PBF (reduction, 44.7 +/- 7% to 42.2 +/- 8%). Changing from the SP to PP position at PEEP induced a similar, but more marked, redistribution of PBF and a significant reduction in the coefficient of variation from 53 +/- 13% to 30.4 +/- 7% (p < 0.001). In the SP, PEEP redistributed PBF toward the posterior, inferior, and central regions without changing the heterogeneity of PBF. In the PP, PEEP had little effect on the PBF redistribution but significantly reduced the coefficient of variation of PBF from 42.2 +/- 8% to 30.4 +/- 7% (p < 0.05). Pigs in the PP had altered gravitational dependence of PBF compared to that observed when pigs were in the SP. This effect was enhanced by using a PEEP of 10 cm H(2)O.

  3. Negative Pressure Wound Therapy in Maxillofacial Applications

    Directory of Open Access Journals (Sweden)

    Adam J. Mellott

    2016-09-01

    Full Text Available Negative pressure wound therapy has greatly advanced the field of wound healing for nearly two decades, by providing a robust surgical adjunct technique for accelerating wound closure in acute and chronic wounds. However, the application of negative pressure wound therapy in maxillofacial applications has been relatively under utilized as a result of the physical articulations and contours of the head and neck that make it challenging to obtain an airtight seal for different negative pressure wound therapy systems. Adapting negative pressure wound therapies for maxillofacial applications could yield significant enhancement of wound closure in maxillofacial applications. The current review summarizes the basic science underlying negative pressure wound therapy, as well as specific maxillofacial procedures that could benefit from negative pressure wound therapy.

  4. Associations between positive end-expiratory pressure and outcome of patients without ARDS at onset of ventilation: a systematic review and meta-analysis of randomized controlled trials

    NARCIS (Netherlands)

    Serpa Neto, Ary; Filho, Roberto Rabello; Cherpanath, Thomas; Determann, Rogier; Dongelmans, Dave A.; Paulus, Frederique; Tuinman, Pieter Roel; Pelosi, Paolo; de Abreu, Marcelo Gama; Schultz, Marcus J.

    2016-01-01

    The aim of this investigation was to compare ventilation at different levels of positive end-expiratory pressure (PEEP) with regard to clinical important outcomes of intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) at onset of ventilation. Meta-analysis of

  5. Negative pressure pulmonary oedema after septoplasty.

    Science.gov (United States)

    García de Hombre, Alina M; Cuffini, Alejandro; Bonadeo, Alejandro

    2013-01-01

    Negative pressure pulmonary oedema (NPPO) is an anaesthetic complication due to acute obstruction of the upper airway, whose main cause is laryngospasm. The pathophysiology involves a strong negative intrapleural pressure during inspiration against a closed glottis, which triggers excessive pressure in the pulmonary microvasculature. Although its diagnosis can be difficult, its recognition helps to minimise morbidity and mortality. This article presents a case of NPPO due to postextubation laryngospasm. Copyright © 2011 Elsevier España, S.L. All rights reserved.

  6. Methods for Assessing Expiratory Flow Limitation during Tidal Breathing in COPD Patients

    Directory of Open Access Journals (Sweden)

    Nickolaos G. Koulouris

    2012-01-01

    Full Text Available Patients with severe COPD often exhale along the same flow-volume curve during quite breathing as during forced expiratory vital capacity manoeuvre, and this has been taken as indicating expiratory flow limitation at rest (EFLT. Therefore, EFLT, namely, attainment of maximal expiratory flow during tidal expiration, occurs when an increase in transpulmonary pressure causes no increase in expiratory flow. EFLT leads to small airway injury and promotes dynamic pulmonary hyperinflation with concurrent dyspnoea and exercise limitation. In fact, EFLT occurs commonly in COPD patients (mainly in GOLD III and IV stage in whom the latter symptoms are common. The existing up-to-date physiological methods for assessing expiratory flow limitation (EFLT are reviewed in the present work. Among the currently available techniques, the negative expiratory pressure (NEP has been validated in a wide variety of settings and disorders. Consequently, it should be regarded as a simple, non invasive, most practical, and accurate new technique.

  7. Impact of changes of positive end-expiratory pressure on functional residual capacity at low tidal volume ventilation during general anesthesia

    OpenAIRE

    Satoh, Daizoh; Kurosawa, Shin; Kirino, Wakaba; Wagatsuma, Toshihiro; Ejima, Yutaka; Yoshida, Akiko; Toyama, Hiroaki; Nagaya, Kei

    2012-01-01

    Purpose Several reports in the literature have described the effects of positive end-expiratory pressure (PEEP) level upon functional residual capacity (FRC) in ventilated patients during general anesthesia. This study compares FRC in mechanically low tidal volume ventilation with different PEEP levels during upper abdominal surgery. Methods Before induction of anesthesia (awake) for nine patients with upper abdominal surgery, a tight-seal facemask was applied with 2 cmH2O pressure support ve...

  8. High versus low positive end-expiratory pressure during general anaesthesia for open abdominal surgery (PROVHILO trial): a multicentre randomised controlled trial.

    Science.gov (United States)

    Hemmes, Sabrine N T; Gama de Abreu, Marcelo; Pelosi, Paolo; Schultz, Marcus J

    2014-08-09

    The role of positive end-expiratory pressure in mechanical ventilation during general anaesthesia for surgery remains uncertain. Levels of pressure higher than 0 cm H2O might protect against postoperative pulmonary complications but could also cause intraoperative circulatory depression and lung injury from overdistension. We tested the hypothesis that a high level of positive end-expiratory pressure with recruitment manoeuvres protects against postoperative pulmonary complications in patients at risk of complications who are receiving mechanical ventilation with low tidal volumes during general anaesthesia for open abdominal surgery. In this randomised controlled trial at 30 centres in Europe and North and South America, we recruited 900 patients at risk for postoperative pulmonary complications who were planned for open abdominal surgery under general anaesthesia and ventilation at tidal volumes of 8 mL/kg. We randomly allocated patients to either a high level of positive end-expiratory pressure (12 cm H2O) with recruitment manoeuvres (higher PEEP group) or a low level of pressure (≤2 cm H2O) without recruitment manoeuvres (lower PEEP group). We used a centralised computer-generated randomisation system. Patients and outcome assessors were masked to the intervention. Primary endpoint was a composite of postoperative pulmonary complications by postoperative day 5. Analysis was by intention-to-treat. The study is registered at Controlled-Trials.com, number ISRCTN70332574. From February, 2011, to January, 2013, 447 patients were randomly allocated to the higher PEEP group and 453 to the lower PEEP group. Six patients were excluded from the analysis, four because they withdrew consent and two for violation of inclusion criteria. Median levels of positive end-expiratory pressure were 12 cm H2O (IQR 12-12) in the higher PEEP group and 2 cm H2O (0-2) in the lower PEEP group. Postoperative pulmonary complications were reported in 174 (40%) of 445 patients in the higher

  9. Influence of Positive End-Expiratory Pressure on Myocardial Strain Assessed by Speckle Tracking Echocardiography in Mechanically Ventilated Patients

    Directory of Open Access Journals (Sweden)

    Federico Franchi

    2013-01-01

    Full Text Available Purpose. The effects of mechanical ventilation (MV on speckle tracking echocardiography- (STE-derived variables are not elucidated. The aim of the study was to evaluate the effects of positive end-expiratory pressure (PEEP ventilation on 4-chamber longitudinal strain (LS analysis by STE. Methods. We studied 20 patients admitted to a mixed intensive care unit who required intubation for MV and PEEP titration due to hypoxia. STE was performed at three times: (T1 PEEP = 5 cmH2O; (T2 PEEP = 10 cmH2O; and (T3 PEEP = 15 cmH2O. STE analysis was performed offline using a dedicated software (XStrain MyLab 70 Xvision, Esaote. Results. Left peak atrial-longitudinal strain (LS was significantly reduced from T1 to T2 and from T2 to T3 (. Right peak atrial-LS and right ventricular-LS showed a significant reduction only at T3 (. Left ventricular-LS did not change significantly during titration of PEEP. Cardiac chambers’ volumes showed a significant reduction at higher levels of PEEP (. Conclusions. We demonstrated for the first time that incremental PEEP affects myocardial strain values obtained with STE in intubated critically ill patients. Whenever performing STE in mechanically ventilated patients, care must be taken when PEEP is higher than 10 cmH2O to avoid misinterpreting data and making erroneous decisions.

  10. Positive end-expiratory pressure optimization using electric impedance tomography in morbidly obese patients during laparoscopic gastric bypass surgery.

    Science.gov (United States)

    Erlandsson, K; Odenstedt, H; Lundin, S; Stenqvist, O

    2006-08-01

    Morbidly obese patients have an increased risk for peri-operative lung complications and develop a decrease in functional residual capacity (FRC). Electric impedance tomography (EIT) can be used for continuous, fast-response measurement of lung volume changes. This method was used to optimize positive end-expiratory pressure (PEEP) to maintain FRC. Fifteen patients with a body mass index of 49 +/- 8 kg/m(2) were studied during anaesthesia for laparoscopic gastric bypass surgery. Before induction, 16 electrodes were placed around the thorax to monitor ventilation-induced impedance changes. Calibration of the electric impedance tomograph against lung volume changes was made by increasing the tidal volume in steps of 200 ml. PEEP was titrated stepwise to maintain a horizontal baseline of the EIT curve, corresponding to a stable FRC. Absolute FRC was measured with a nitrogen wash-out/wash-in technique. Cardiac output was measured with an oesophageal Doppler method. Volume expanders, 1 +/- 0.5 l, were given to prevent PEEP-induced haemodynamic impairment. Impedance changes closely followed tidal volume changes (R(2) > 0.95). The optimal PEEP level was 15 +/- 1 cmH(2)O, and FRC at this PEEP level was 1706 +/- 447 ml before and 2210 +/- 540 ml after surgery (P depression in spite of a high PEEP level.

  11. Clinical assessment of auto-positive end-expiratory pressure by diaphragmatic electrical activity during pressure support and neurally adjusted ventilatory assist.

    Science.gov (United States)

    Bellani, Giacomo; Coppadoro, Andrea; Patroniti, Nicolò; Turella, Marta; Arrigoni Marocco, Stefano; Grasselli, Giacomo; Mauri, Tommaso; Pesenti, Antonio

    2014-09-01

    Auto-positive end-expiratory pressure (auto-PEEP) may substantially increase the inspiratory effort during assisted mechanical ventilation. Purpose of this study was to assess whether the electrical activity of the diaphragm (EAdi) signal can be reliably used to estimate auto-PEEP in patients undergoing pressure support ventilation and neurally adjusted ventilatory assist (NAVA) and whether NAVA was beneficial in comparison with pressure support ventilation in patients affected by auto-PEEP. In 10 patients with a clinical suspicion of auto-PEEP, the authors simultaneously recorded EAdi, airway, esophageal pressure, and flow during pressure support and NAVA, whereas external PEEP was increased from 2 to 14 cm H2O. Tracings were analyzed to measure apparent "dynamic" auto-PEEP (decrease in esophageal pressure to generate inspiratory flow), auto-EAdi (EAdi value at the onset of inspiratory flow), and IDEAdi (inspiratory delay between the onset of EAdi and the inspiratory flow). The pressure necessary to overcome auto-PEEP, auto-EAdi, and IDEAdi was significantly lower in NAVA as compared with pressure support ventilation, decreased with increase in external PEEP, although the effect of external PEEP was less pronounced in NAVA. Both auto-EAdi and IDEAdi were tightly correlated with auto-PEEP (r = 0.94 and r = 0.75, respectively). In the presence of auto-PEEP at lower external PEEP levels, NAVA was characterized by a characteristic shape of the airway pressure. In patients with auto-PEEP, NAVA, compared with pressure support ventilation, led to a decrease in the pressure necessary to overcome auto-PEEP, which could be reliably monitored by the electrical activity of the diaphragm before inspiratory flow onset (auto-EAdi).

  12. Positive end-expiratory pressure (PEEP) does not depress left ventricular function in patients with pulmonary edema

    International Nuclear Information System (INIS)

    Calvin, J.E.; Driedger, A.A.; Sibbald, W.J.

    1981-01-01

    Researchers evaluated the effects of positive end-expiratory pressure (PEEP) on left ventricular function in 15 patients with acute respiratory insufficiency secondary to pulmonary edema with invasive (pressure; flow) measurements and radionuclide angiography (RA). Using RNA allowed a definition of the left ventricular ejection fraction (LVEF), and then calculation of the left ventricular end-diastolic volume (LVEDV), both before and after PEEP. With a mean PEEP of 14.2 +/- 1.8 cm H2O (mean +/- SD) (range, 10 to 15), a fall in the cardiac index (4.34 +/- 1.5 to 3.84 +/- 1.4 L/min/M2; p less than 0.001) was accompanied by a significant decrease in the stroke volume index (42 +/- 13 to 39 +/- 12 ml/beat M2; p less than 0.01) and pulse rate (103.4 +/- 14.3 to 98 +/- 13.5 beats/min; p less than 0.01). The decrease in the stroke volume index was primarily due to a significant decrease in left ventricular preload (LVEDV) from 85.9 +/- 19 to 71.4 +/- 21.4 ml/m2 (p less than 0.01). Simultaneously, the mean LVEF increased from 0.47 +/- 0.10 to 0.53 +/- 0.08 (p less than 0.05), despite a significant increase in the systemic vascular resistance (1,619 +/- 575 to 1,864 +/- 617 dynes . s. cm-5/M2; p less than 0.01). Researchers concluded that the use of PEEP in patients with acute pulmonary edema, to the degree used in this study, may depress cardiac output by simply decreasing left ventricular preload. Researchers were unable to produce any evidence that would support a change in the contractile state of the left ventricle as a cause of depressed forward flow with the use of PEEP

  13. Effects of positive expiratory pressure on pulmonary clearance of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid in healthy individuals

    International Nuclear Information System (INIS)

    Albuquerque, Isabella Martins de; Masiero, Paulo Ricardo; Menna-Barreto, Sergio Saldanha; Resqueti, Vanessa Regiane; Fregonezi, Guilherme Augusto de Freitas

    2016-01-01

    Objective: To evaluate the effects of positive expiratory pressure (PEP) on pulmonary epithelial membrane permeability in healthy subjects. Methods: We evaluated a cohort of 30 healthy subjects (15 males and 15 females) with a mean age of 28.3 ± 5.4 years, a mean FEV 1 /FVC ratio of 0.89 ± 0.14, and a mean FEV 1 of 98.5 ± 13.1% of predicted. Subjects underwent technetium-99m labeled diethylenetriaminepentaacetic acid ( 99m TcDTPA) radio aerosol inhalation lung scintigraphy in two stages: during spontaneous breathing; and while breathing through a PEP mask at one of three PEP levels—10 cmH 2 O (n = 10), 15 cmH 2 O (n = 10), and 20 cmH 2 O (n = 10). The 99m Tc-DTPA was nebulized for 3 min, and its clearance was recorded by scintigraphy over a 30-min period during spontaneous breathing and over a 30-min period during breathing through a PEP mask. Results: The pulmonary clearance of 99m Tc-DTPA was significantly shorter when PEP was applied—at 10 cmH 2 O (p = 0.044), 15 cmH 2 O (p = 0.044), and 20 cmH 2 O (p = 0.004) - in comparison with that observed during spontaneous breathing. Conclusions: Our findings indicate that PEP, at the levels tested, is able to induce an increase in pulmonary epithelial membrane permeability and lung volume in healthy subjects. (author)

  14. Differential Effects of Intraoperative Positive End-expiratory Pressure (PEEP) on Respiratory Outcome in Major Abdominal Surgery Versus Craniotomy

    Science.gov (United States)

    Vidal Melo, Marcos F.; Staehr-Rye, Anne Kathrine; Bittner, Edward A.; Kurth, Tobias; Eikermann, Matthias

    2016-01-01

    Objectives In this study, we examined whether (1) positive end-expiratory pressure (PEEP) has a protective effect on the risk of major postoperative respiratory complications in a cohort of patients undergoing major abdominal surgeries and craniotomies, and (2) the effect of PEEP is differed by surgery type. Background Protective mechanical ventilation with lower tidal volumes and PEEP reduces compounded postoperative complications after abdominal surgery. However, data regarding the use of intraoperative PEEP is conflicting. Methods In this observational study, we included 5915 major abdominal surgery patients and 5063 craniotomy patients. Analysis was performed using multivariable logistic regression. The primary outcome was a composite of major postoperative respiratory complications (respiratory failure, reintubation, pulmonary edema, and pneumonia) within 3 days of surgery. Results Within the entire study population (major abdominal surgeries and craniotomies), we found an association between application of PEEP ≥5cmH2O and a decreased risk of postoperative respiratory complications compared with PEEP 5cmH2O was associated with a significant lower odds of respiratory complications in patients undergoing major abdominal surgery (odds ratio 0.53, 95% confidence interval 0.39 – 0.72), effects that translated to deceased hospital length of stay [median hospital length of stay : 6 days (4–9 days), incidence rate ratios for each additional day: 0.91 (0.84 - 0.98)], whereas PEEP >5cmH2O was not significantly associated with reduced odds of respiratory complications or hospital length of stay in patients undergoing craniotomy. Conclusions The protective effects of PEEP are procedure specific with meaningful effects observed in patients undergoing major abdominal surgery. Our data suggest that default mechanical ventilator settings should include PEEP of 5–10cmH2O during major abdominal surgery. PMID:26496082

  15. Effects of positive end-expiratory pressure on intraoperative core temperature in patients undergoing posterior spine surgery: prospective randomised trial.

    Science.gov (United States)

    Seo, Hyungseok; Do Son, Je; Lee, Hyung-Chul; Oh, Hyung-Min; Jung, Chul-Woo; Park, Hee-Pyoung

    2018-03-01

    Objective Positive end-expiratory pressure (PEEP) causes carotid baroreceptor unloading, which leads to thermoregulatory peripheral vasoconstriction. However, the effects of PEEP on intraoperative thermoregulation in the prone position remain unknown. Methods Thirty-seven patients undergoing spine surgery in the prone position were assigned at random to receive either 10 cmH 2 O PEEP (Group P) or no PEEP (Group Z). The primary endpoint was core temperature 180 minutes after intubation. Secondary endpoints were delta core temperature (difference in core temperature between 180 minutes and immediately after tracheal intubation), incidence of intraoperative hypothermia (core temperature of peripheral vasoconstriction-related data. Results The median [interquartile range] core temperature 180 minutes after intubation was 36.1°C [35.9°C-36.2°C] and 36.0°C [35.9°C-36.4°C] in Groups Z and P, respectively. The delta core temperature and incidences of intraoperative hypothermia and peripheral vasoconstriction were not significantly different between the two groups. The peripheral vasoconstriction threshold (36.2°C±0.5°C vs. 36.7°C±0.6°C) was lower and the onset of peripheral vasoconstriction (66 [60-129] vs. 38 [28-70] minutes) was slower in Group Z than in Group P. Conclusions Intraoperative PEEP did not reduce the core temperature decrease in the prone position, although it resulted in an earlier onset and higher threshold of peripheral vasoconstriction.

  16. Effects of positive end-expiratory pressure on mechanical ventilation duration after coronary artery bypass grafting: a randomized clinical trial.

    Science.gov (United States)

    Lago Borges, Daniel; José da Silva Nina, Vinícius; Pereira Baldez, Thiago Eduardo; de Albuquerque Gonçalves Costa, Marina; Pereira dos Santos, Natália; Mendes Lima, Ilka; Lima da Silva Lula, Josimary

    2014-01-01

    Patients undergoing cardiac surgery remain on mechanical ventilation postoperatively until they regain consciousness. Positive end-expiratory pressure (PEEP) may influence the duration of mechanical ventilation after coronary artery bypass grafting (CABG). The aim of this study was to compare the effects of different levels of PEEP on the duration of mechanical ventilation after coronary artery bypass grafting. This was a randomized clinical trial with 136 patients undergoing CABG between January 2011 and March 2012. We divided the patients into three groups with different levels of PEEP at the onset of mechanical ventilation: Group A, PEEP=5 cmH2O (n=44); Group B, PEEP=8 cmH2O (n=47) and Group C, PEEP=10 cmH2O (n=45). Mechanical ventilation time was obtained from a Physical Therapy Evaluation Form. We excluded patients with chronic obstructive pulmonary disease and those requiring concomitant, emergency or off-pump surgeries. For statistical analysis, we used the Kruskal-Wallis, G and Chi-square tests, with pweaning from mechanical ventilation until 12 hours after intensive care unit (ICU) admission, we saw a statistically different duration of mechanical ventilation between groups (p=0.029). In Group A, the average mechanical ventilation time was 6.7±3.2 hours; it was 6.8±3.3 hours in Group B and 5.1±2.9 hours in Group C. The use of higher levels of PEEP was associated with shorter duration of mechanical ventilation in postoperative CABG patients.

  17. Effects of respiratory rate, plateau pressure, and positive end-expiratory pressure on PaO2 oscillations after saline lavage.

    Science.gov (United States)

    Baumgardner, James E; Markstaller, Klaus; Pfeiffer, Birgit; Doebrich, Marcus; Otto, Cynthia M

    2002-12-15

    One of the proposed mechanisms of ventilator-associated lung injury is cyclic recruitment of atelectasis. Collapse of dependent lung regions with every breath should lead to large oscillations in PaO2 as shunt varies throughout the respiratory cycle. We placed a fluorescence-quenching PO2 probe in the brachiocephalic artery of six anesthetized rabbits after saline lavage. Using pressure-controlled ventilation with oxygen, ventilator settings were varied in random order over three levels of positive end-expiratory pressure (PEEP), respiratory rate (RR), and plateau pressure minus PEEP (Delta). Dependence of the amplitude of PaO2 oscillations on PEEP, RR, and Delta was modeled by multiple linear regression. Before lavage, arterial PO2 oscillations varied from 3 to 22 mm Hg. After lavage, arterial PO2 oscillations varied from 5 to 439 mm Hg. Response surfaces showed markedly nonlinear dependence of amplitude on PEEP, RR, and Delta. The large PaO2 oscillations observed provide evidence for cyclic recruitment in this model of lung injury. The important effect of RR on the magnitude of PaO2 oscillations suggests that the static behavior of atelectasis cannot be accurately extrapolated to predict dynamic behavior at realistic breathing frequencies.

  18. Positive end-expiratory pressure improves survival in a rodent model of cardiopulmonary resuscitation using high-dose epinephrine.

    Science.gov (United States)

    McCaul, Conán; Kornecki, Alik; Engelberts, Doreen; McNamara, Patrick; Kavanagh, Brian P

    2009-10-01

    Multiple interventions have been tested in models of cardiopulmonary resuscitation (CPR) to optimize drug use, chest compressions, and ventilation. None has studied the effects of positive end-expiratory pressure (PEEP) on outcome. We hypothesized that because PEEP can reverse pulmonary atelectasis, lower pulmonary vascular resistance, and potentially improve cardiac output, its use during CPR would increase survival. Anesthetized Sprague-Dawley rats were exposed to 1 min of asphyxial cardiac arrest. Resuscitation was standardized and consisted of chest compressions, oxygen (Fio(2) 1.0), and IV epinephrine 30 microg/kg (Series 1) and 10 microg/kg (Series 2). Left ventricular function was assessed by echocardiography (Series 1), and animals were randomized to receive either 5 cm H(2)O PEEP or zero PEEP at commencement of CPR and throughout resuscitation. Survival was defined as the presence of a spontaneous circulation 60 or 120 min (Series 2) after initial resuscitation. There were no baseline differences between the groups. In Series 1, administration of 5 cm H(2)O PEEP (Fio(2) 1.0 and 0.21) was associated with improved survival compared with zero PEEP (7/9 and 6/6 vs 0/9, P CPR did not adversely affect left ventricular systolic function or arterial blood pressure. The outcome differences were not due to increased oxygenation because the rank order of survival was 5 cm H(2)O PEEP (Fio(2) 1.0) approximately 5 cm H(2)O PEEP (Fio(2) 0.21) > zero PEEP (Fio(2) 1.0), whereas the rank order of Pao(2) was 5 cm H(2)O PEEP (Fio(2) 1.0) > 5 cm H(2)O PEEP (Fio(2) 0.21) approximately zero PEEP (Fio(2) 1.0). In an additional series in which epinephrine 10 microg/kg was used (Series 2), the survival was 100% with no beneficial effects of PEEP. In asphyxial cardiac arrest in a small rodent model, continuous application of PEEP (5 cm H(2)O) during and after CPR had beneficial effects on survival that were independent of oxygenation and without adverse cardiovascular effects.

  19. Low pulmonary artery flush perfusion pressure combined with high positive end-expiratory pressure reduces oedema formation in isolated porcine lungs

    International Nuclear Information System (INIS)

    Schumann, Stefan; Schließmann, Stephan J; Wagner, Giskard; Goebel, Ulrich; Priebe, Hans-Joachim; Guttmann, Josef; Kirschbaum, Andreas

    2010-01-01

    Flush perfusion of the pulmonary artery with organ protection solution is a standard procedure before lung explantation. However, rapid flush perfusion may cause pulmonary oedema which is deleterious in the lung transplantation setting. In this study we tested the hypotheses that high pulmonary perfusion pressure contributes to the development of pulmonary oedema and positive end-expiratory pressure (PEEP) counteracts oedema formation. We expected oedema formation to increase weight and decrease compliance of the lungs on the basis of a decrease in alveolar volume as fluid replaces alveolar air spaces. The pulmonary artery of 28 isolated porcine lungs was perfused with a low-potassium dextrane solution at low (mean 27 mmHg) or high (mean 40 mmHg) pulmonary artery pressure (PAP) during mechanical ventilation at low (4 cmH 2 O) or high (8 cmH 2 O) PEEP, respectively. Following perfusion and storage, relative increases in lung weight were smaller (p < 0.05) during perfusion at low PAP (62 ± 32% and 42 ± 26%, respectively) compared to perfusion at high PAP (133 ± 54% and 87 ± 30%, respectively). Compared to all other PAP–PEEP combinations, increases in lung weight were smallest (44 ± 9% and 27 ± 12%, respectively), nonlinear intratidal lung compliance was largest (46% and 17% respectively, both p < 0.05) and lung histology showed least infiltration of mononuclear cells in the alveolar septa, and least alveolar destruction during the combination of low perfusion pressure and high PEEP. The findings suggest that oedema formation during pulmonary artery flush perfusion in isolated and ventilated lungs can be reduced by choosing low perfusion pressure and high PEEP. PAP–PEEP titration to minimize pulmonary oedema should be based on lung mechanics and PAP monitoring

  20. Active Intracystic Negative Pressure Could Induce Osteogenesis.

    Science.gov (United States)

    Castro-Núñez, Jaime

    2018-02-23

    Based on previous findings, the author introduces the term "sugosteogenesis," a biological phenomenon that occurs by using the Evocyst, a device that exerts active intracystic negative pressure. The term "sugosteogenesis" comes from the Latin word "sugo-," meaning "suck," and Greek words "osteo-," meaning "bone," and genesis, "origin."

  1. Negative pressure wound therapy: clinical utility

    Directory of Open Access Journals (Sweden)

    Sandoz H

    2015-04-01

    Full Text Available Heidi Sandoz Accelerate CIC, Mile End Hospital, London, UK Abstract: Negative pressure wound therapy (NPWT, also known as topical negative pressure therapy, has been increasingly used in health care for the management of a wide variety of wounds over the last 2–3 decades. It is an advanced therapy that can be helpful to accelerate wound healing in both acute and chronic wounds by delivering negative pressure (suction to the wound bed. More recent advancements in the application of NPWT have provided clinicians with wider choices of utilization. There are now devices available that can deliver irrigation to the wound bed, be used for closed surgical incisions, or are disposable and highly portable. Systematic reviews considering NPWT have been published previously. These usually focus on one wound group or device and fail to offer practical clinical guidance due to the scrutiny offered to the evidence via a systematic review process. Here, an overview of the history of NPWT, the varieties of device available, their wide clinical application, and the evidence to support its use are explored in a pragmatic way. Keywords: negative pressure, wound, incision, healing, pain 

  2. Safety and effectiveness of alveolar recruitment maneuvers and positive end-expiratory pressure during general anesthesia for cesarean section: a prospective, randomized trial.

    Science.gov (United States)

    Aretha, D; Fligou, F; Kiekkas, P; Messini, C; Panteli, E; Zintzaras, E; Karanikolas, M

    2017-05-01

    During cesarean section, the supine position reduces functional residual capacity and worsens lung compliance. We tested the hypothesis that alveolar recruitment maneuvers and positive end-expiratory pressure improve lung compliance in women undergoing general anesthesia for cesarean section. Ninety women undergoing cesarean section were randomly assigned to one of two groups in a prospective, double-blind trial. In the alveolar recruitment maneuver group, pressure-control ventilation was used and inspiratory time was increased to 50% after delivery; positive end-expiratory pressure was increased to 20cmH 2 O and peak airway inspiratory pressure gradually increased to 45-50cmH 2 O. Volume-control ventilation was then used with low tidal volumes (6mL/kg) and positive end-expiratory pressure was reduced stepwise to 8cmH 2 O. In the control group, alveolar recruitment maneuvers were not used. Data were collected before and 3, 10 and 20min after the alveolar recruitment maneuver, before extubation and postoperatively at 10 and 20min. Dynamic compliance, peak airway inspiratory pressure, PaO 2 and PaO 2 /FiO 2 were significantly different in the alveolar recruitment maneuver group compared to controls at all time points during surgery except at baseline. Oxygen saturation was significantly greater in the alveolar recruitment maneuver group at 10 and 20min and before extubation. Dynamic compliance was 29.7-42.5% higher and peak airway inspiratory pressure 3.6-10.2% lower in the alveolar recruitment maneuver group compared to controls. The PaO 2 , PaO 2 /FiO 2 and oxygen saturation were higher (9.4-12%, 10.3-11.9% and 0.4-1.3%, respectively) in the alveolar recruitment maneuver group. Postoperatively, PaO 2 and oxygen saturation were significantly higher in the alveolar recruitment maneuver group compared to controls (PaO 2 9.2% at 10min and 8.4% at 20min, oxygen saturation 0.8% at 10min and 1.1% at 20min). There were no significant differences in hemodynamic stability or

  3. Positive end expiratory pressure for preterm infants requiring conventional mechanical ventilation for respiratory distress syndrome or bronchopulmonary dysplasia.

    Science.gov (United States)

    Bamat, Nicolas; Millar, David; Suh, Sanghee; Kirpalani, Haresh

    2012-01-18

    Conventional mechanical ventilation (CMV) of neonates has been used as a treatment of respiratory failure for over 30 years. While CMV facilitates gas exchange, it may simultaneously damage the lung. Positive end expiratory pressure (PEEP) has received less attention than other ventilation parameters when considering this balance of benefit and possible harm. While an appropriate level of PEEP may exert substantial benefits in ventilation, both inappropriately low or high levels may lead to harm. An appropriate level of PEEP for neonates may also be best achieved by an individualized approach. 1. To compare the effects of different levels of PEEP in preterm newborn infants requiring CMV for respiratory distress syndrome (RDS).2. To compare the effects of different levels of PEEP in preterm infants requiring CMV for bronchopulmonary dysplasia (BPD).3. To compare the effects of different methods for individualizing PEEP to an optimal level in preterm newborn infants requiring CMV for RDS. The search was performed in accordance with the standard search strategy for the Cochrane Neonatal Review Group. The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), Ovid MEDLINE, EMBASE, study references and experts were utilized for study identification. All randomized and quasi-randomized controlled trials studying preterm infants (less than 37 weeks gestational age) requiring CMV with endotracheal intubation and undergoing randomization to either different PEEP levels (RDS or BPD) or two or more alternative methods for individualizing PEEP levels (RDS only) were included. Cross-over trials were included but we limited the findings to those in the first cross-over period. Data collection and analysis were performed in accordance with the recommendations of the Cochrane Neonatal Review Group. An initial evaluation identified 10 eligible articles. Ultimately, a single study met our inclusion criteria. The study addressed the effects of different

  4. Sensitivity and specificity of hypopnoea detection using nasal pressure in the presence of a nasal expiratory resistive device (Provent®)

    International Nuclear Information System (INIS)

    Milne, Stephen; Amis, Terence C; Wheatley, John R; Kairaitis, Kristina

    2014-01-01

    Nasal expiratory resistive valves (Provent ® ) have been proposed as novel therapy for obstructive sleep apnea. We compared pressure measurements from a standard nasal pressure catheter used to assess nasal airflow during sleep with those from nasal expiratory resistive device with attached proprietary nasal pressure cannula. Nasal pressure cannula or Provent ® + proprietary nasal pressure cannula were attached to a bench model of human anterior nares and nasal passages, and pressure measured (P). Respiratory airflows generated by a subject breathing were applied to rear of model and airflow ( V-dot ) measured via pneumotachograph. Airflow amplitude (Δ V-dot ) was plotted against pressure amplitude (ΔP). Hypopnoea detection (<50% Δ V-dot ) sensitivity and specificity was tested by expressing ΔP in terms of two reference breaths: reference breath 1, Δ V-dot 0.55 L s −1  = 100%; and reference breath 2, Δ V-dot 0.45 L s −1  = 100%. ΔP/Δ V-dot relationships were linear for Δ V-dot  ≤ 0.55 L s −1 ; ΔP = 0.37ΔV + 0.16 (nasal pressure cannula), ΔP = 2.7ΔV + 0.12 (Provent ® + proprietary nasal pressure cannula); both R 2  > 0.65, p < 0.0001; p < 0.0001 for between slope difference). For nasal pressure cannula, specificity of hypopnoea detection differed between reference breaths one and two (80.2% and 40.0%, respectively), and Provent ® + proprietary nasal pressure cannula (30.3% and 74.2%, respectively). Quantification of airflow obstruction in the presence of Provent ® + proprietary nasal pressure cannula is greatly influenced by the reference breath chosen to determine a reduction in nasal airflow. Reported variability in therapeutic response to nasal expiratory resistive devices may relate to differences in measurement technique specificity used to quantify the severity of sleep disordered breathing. (paper)

  5. Passive leg-raising and end-expiratory occlusion tests perform better than pulse pressure variation in patients with low respiratory system compliance.

    Science.gov (United States)

    Monnet, Xavier; Bleibtreu, Alexandre; Ferré, Alexis; Dres, Martin; Gharbi, Rim; Richard, Christian; Teboul, Jean-Louis

    2012-01-01

    We tested whether the poor ability of pulse pressure variation to predict fluid responsiveness in cases of acute respiratory distress syndrome was related to low lung compliance. We also tested whether the changes in cardiac index induced by passive leg-raising and by an end-expiratory occlusion test were better than pulse pressure variation at predicting fluid responsiveness in acute respiratory distress syndrome patients. Prospective study. Medical intensive care unit. We included 54 patients with circulatory shock (63 ± 13 yrs; Simplified Acute Physiology Score II, 63 ± 24). Twenty-seven patients had acute respiratory distress syndrome (compliance of the respiratory system, 22 ± 3 mL/cm H2O). In nonacute respiratory distress syndrome patients, the compliance of the respiratory system was 45 ± 9 mL/cm H2O. We measured the response of cardiac index (transpulmonary thermodilution) to fluid administration (500 mL saline). Before fluid administration, we recorded pulse pressure variation and the changes in pulse contour analysis-derived cardiac index induced by passive leg-raising and end-expiratory occlusion. Fluid increased cardiac index ≥ 15% (44% ± 39%) in 30 "responders." Pulse pressure variation was significantly correlated with compliance of the respiratory system (r = .58), but not with tidal volume. The higher the compliance of the respiratory system, the better the prediction of fluid responsiveness by pulse pressure variation. A compliance of the respiratory system of 30 mL/cm H2O was the best cut-off for discriminating patients regarding the ability of pulse pressure variation to predict fluid responsiveness. If compliance of the respiratory system was >30 mL/cm H2O, then the area under the receiver-operating characteristics curve for predicting fluid responsiveness was not different for pulse pressure variation and the passive leg-raising and end-expiratory occlusion tests (0.98 ± 0.03, 0.91 ± 0.06, and 0.97 ± 0.03, respectively). By contrast

  6. [ProSeal™laryngeal mask in normal weight and obese patients : oxygenation under pressure-controlled ventilation and different end-expiratory pressures].

    Science.gov (United States)

    Goldmann, K; Gerlach, M; Bornträger, C

    2011-10-01

    Most of the data on combining pressure-controlled ventilation (PCV) with positive end-expiratory pressure (PEEP) come from studies with an endotracheal tube (ETT) whereas data on utilization of PEEP with a laryngeal mask airway (LMA) are limited. The LMA-ProSeal® (PLMA) forms a more effective seal of the airway than the LMA-Classic™ (CLMA). The application of PEEP when PCV is used with the PLMA could have an impact on oxygenation in adult patients. For this study 148 patients with an mean age of 44 years (range18-65 years) and mean weight of 86 kg (range 49-120 kg) were recruited in 2 groups: group N ((Normal)): body-mass index (BMI) cmH(2)O, 5 cmH(2)O or 8 cmH(2)O PEEP. An arterial blood gas sample was taken 50 min after induction of anesthesia under an inspiratory oxygen fraction (F(I)O(2)) of 0.3. In the first part partial oxygen pressure (p(a)O(2)) under 0 cmH(2)O was compared with p(a)O(2) under 5 cmH(2)O and in the second part p(a)O(2) under 5 cmH(2)O was compared with p(a)O(2) under 8 cmH(2)O. A significant difference was set as pcmH(2)O. Both findings are in contrast to findings of studies using an ETT which suggests that higher pressures (40 cmH(2)O) are needed for recruitment of collapsed alveoli and higher PEEP (10 cmH(2)O) is needed to produce a clinically significant improvement in oxygenation in obese patients. The results of this study support data showing that the consequences of bronchopulmonary airway reactions known to occur with an ETT are less pronounced or absent when an LMA is used.

  7. Early warning and prevention of pneumonia in acute leukemia by patient education, spirometry, and positive expiratory pressure

    DEFF Research Database (Denmark)

    Møller, Tom; Moser, Claus; Adamsen, Lis

    2016-01-01

    fever, emphasizing the need to approach infection protection with complementary efforts. In a randomized controlled design, we examined the applicability of patient-performed daily spirometry [forced expiratory volume in one second (FEV1)] as an early warning tool and explored the effectiveness...... in their continuous daily measurement of FEV1 and use of PEP. Daily measures of FEV1 may be an important early warning tool for assessment of pulmonary deterioration during critical phases of neutropenia. We suggest that strategic patient education in the use of spirometry and PEP should be part of standard of care...

  8. Physiological techniques for detecting expiratory flow limitation during tidal breathing

    Directory of Open Access Journals (Sweden)

    N.G. Koulouris

    2011-09-01

    Full Text Available Patients with severe chronic obstructive pulmonary disease (COPD often exhale along the same flow–volume curve during quiet breathing as they do during the forced expiratory vital capacity manoeuvre, and this has been taken as an indicator of expiratory flow limitation at rest (EFLT. Therefore, EFLT, namely attainment of maximal expiratory flow during tidal expiration, occurs when an increase in transpulmonary pressure causes no increase in expiratory flow. EFLT leads to small airway injury and promotes dynamic pulmonary hyperinflation, with concurrent dyspnoea and exercise limitation. In fact, EFLT occurs commonly in COPD patients (mainly in Global Initiative for Chronic Obstructive Lung Disease III and IV stage, in whom the latter symptoms are common, but is not exclusive to COPD, since it can also be detected in other pulmonary and nonpulmonary diseases like asthma, acute respiratory distress syndrome, heart failure and obesity, etc. The existing up to date physiological techniques of assessing EFLT are reviewed in the present work. Among the currently available techniques, the negative expiratory pressure has been validated in a wide variety of settings and disorders. Consequently, it should be regarded as a simple, noninvasive, practical and accurate new technique.

  9. Positive end-expiratory pressure increases pulmonary clearance of inhaled 99mTc-DTPA in nonsmokers but not in healthy smokers

    International Nuclear Information System (INIS)

    Nolop, K.B.; Braude, S.; Royston, D.; Maxwell, D.L.; Hughes, J.M.B.

    1987-01-01

    Positive end-expiratory pressure (PEEP) is widely used in the treatment of severe pulmonary oedema, although its effects on the clearance of water and small solutes from alveolus to blood are not well characterized. We studied the effect of the application of 10 cmH 2 O of PEEP on the flux of inhaled 99 mTc-diethylene-triamine-penta-acetic acid (DTPA) from lung to blood in six healthy smoking and six nonsmoking subjects. The rate of flux was corrected for possible changes in pulmonary blood volume during PEEP by use of an intravenous injection of 99m Tc-DTPA. The baseline clearance rate (K,%.min -1 ) for nonsmokers was 1.48±0.12 (mean±SE) and increased to 2.40±0.29 during PEEP (p<0.05). In contrast, the mean clearance rate for smokers was 3.26±0.82 at baseline and 3.03±0.82 during PEEP (p=NS). The application of positive end-expiratory pressure appears to increase alveolar solute flux in nonsmokers but not in smokers, suggesting that the pathway for solute clearance in smokers is governed by different rate-limiting steps to those of nonsmokers

  10. Intraoperative and postoperative evaluation of low tidal volume combined with low-level positive end-expiratory pressure ventilation in laparoscopic surgery in elderly patients

    Directory of Open Access Journals (Sweden)

    Ye-Qiu Li

    2016-01-01

    Full Text Available Objective: To evaluate intraoperative and postoperative condition of low tidal volume combined with low-level positive end-expiratory pressure ventilation in laparoscopic surgery in elderly patients. Methods: A total of 176 cases of elderly patients (more than 60 years old receiving laparoscopic surgery in our hospital from July 2013 to July 2015 were selected as research subjects and randomly divided into observation group and control group, each group included 88 cases, control group received conventional ventilation strategy, observation group received low tidal volume combined with low-level positive end-expiratory pressure ventilation strategy, and then levels of hemodynamic indexes, respiratory mechanical indexes, serology indexes and cerebral vessel related indexes, etc of two groups were compared. Results: Intraoperative and postoperative heart rate and mean arterial pressure levels of observation group were lower than those of control group, arterial partial pressure of oxygen and oxygenation index levels were higher than those of control group and differences had statistical significance (P<0.05; intraoperative APIP and Pplat values of observation group were lower than those of control group, Cs value was higher than that of control group and differences had statistical significance (P<0.05; intraoperative and postoperative serum IL-8 and TNF-α levels of observation group were lower than those of control group, IL-10 level was higher than that of control group and differences had statistical significance (P<0.05; intraoperative and postoperative PjvO2, SjvO2 and CjvO2 levels of observation group were higher than those of control group, Da-jvO2 level was lower than that of control group and differences had statistical significance (P<0.05. Conclusions: When elderly patients receive laparoscopic surgery, the use of low tidal volume combined with low-level positive end-expiratory pressure ventilation strategy can stabilize hemodynamic

  11. Topical negative pressure therapy: mechanisms and indications.

    Science.gov (United States)

    Banwell, Paul E; Musgrave, Melinda

    2004-06-01

    Topical negative pressure (TNP) therapy has emerged as a high-technology, microprocessor-controlled physical wound-healing modality. Complex effects at the wound-dressing interface following application of a controlled vacuum force have been documented. These include changes on a microscopic, molecular level and on a macroscopic, tissue level: interstitial fluid flow and exudate management, oedema reduction, effects on wound perfusion, protease profiles, growth factor and cytokine expression and cellular activity, all leading to enhanced granulation tissue formation and improved wound-healing parameters. Primary indications for clinical use have been documented and include traumatic wounds, open abdominal wounds, infected sternotomy wounds, wound bed preparation, complex diabetic wounds and skin-graft fixation. Whilst this therapy now forms an essential part of the wound healing armamentarium, extensive clinical trials are recommended to confirm efficacy and delineate its optimum use.

  12. Negative pressure wound therapy and nurse education.

    Science.gov (United States)

    Cray, Amy

    2017-08-10

    there can be serious consequences for patients if negative pressure wound therapy (NPWT) is performed incorrectly and patient safety must be paramount. The existing literature was found to mainly concentrate on the use of the technology from the patient perspective. This article examines the opinions of nurses who apply the therapy. five staff nurses from different areas with differing experience levels were interviewed in a semi-structured manner. The transcribed interviews were coded, sorted into themes and analysed. the themes were: enhancing knowledge and understanding, managing problematic pumps, formalised and interactive training, and efficacy and healing. There was a lack of standardised training provided for the nurses interviewed. Overall the nurses were aware of the basic evidence behind the treatment but would have liked additional support in this area as well as some practical, less pressured training. This complements the existing literature. nurses are expected to learn difficult and highly specialised skills quickly within a busy ward environment, often with no prior training or preparation. As things can go wrong, with the potential for patient harm, it is vital that nurses get these skills right first time, but it is difficult to do this in a practical, fast and cost-effective way. There is scope for future research in the area and perhaps the development of an online training tool to assist nurses in understanding and undertaking a new procedure.

  13. Evaluation of continuous and intermittent myocardial topical negative pressure

    DEFF Research Database (Denmark)

    Lindstedt, Sandra; Malmsjö, Malin; Gesslein, Bodil

    2008-01-01

    Topical negative pressure, commonly used in wound therapy, has been shown to increase blood flow and stimulate angiogenesis in subcutaneous tissue and skeletal muscle. In wound therapy, intermittent negative pressure is often preferred to continuous negative pressure as tissue exposed to intermit...

  14. Renal effects of continuous negative pressure breathing

    Science.gov (United States)

    Kinney, M. J.

    1975-01-01

    Continuous negative pressure breathing (CNPB) was utilized to simulate the thoracic vascular distension of zero G in 11 anesthetized rats. The animals underwent renal clearance and micropuncture renal nephron studies before, during, and after CNPB. Four rats were pretreated with a high salt diet and I-M desoxycorticosterone (DOCA) in excess. None of these rats diuresed with CNPB. In contrast, five of the seven remaining rats increased the fraction of the filtered sodium excreted and their urinary flow rate. Potassium excretion increased. End proximal tubular fluid specimen's TF/P inulin ratios were unchanged. Whole kidney and single nephron glomerular filtration rates fell 10%. CNPB, a mechanism for atrial distension, appears to cause in the rat a decrease in distal tubular sodium and water reabsorption. Exogenous mineral-corticoid prevents the diuresis, saluresis, and kaluresis. The adequacy of other nonatrial volume control mechanisms in regulating renal salt and water conservation in opposition to the studied atrial-renal (Henry-Gauer) reflex of thoracic vascular distension is confirmed.

  15. The acute effects of a single session of expiratory muscle strength training on blood pressure, heart rate, and oxygen saturation in healthy adults.

    Science.gov (United States)

    Laciuga, Helena; Davenport, Paul; Sapienza, Christine

    2012-01-01

    Expiratory muscle strength training (EMST) is a rehabilitative program that has been tested for outcomes related to respiratory muscle strength, cough, swallow, and voice function in healthy young adult, elderly individuals, and in patients with progressive neurodegenerative disease. Because EMST has been used in patient care, the associated cardiovascular responses during EMST are of importance. This study investigated the changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and oxygen saturation (SpO(2)) during one session of EMST in healthy, young adults as a preliminary study of device safety. Thirty-one participants completed a single session of 25 trials with the EMST device. Valsalva maneuvers were performed at the beginning and at the end of the EMST trials for task comparison. The SBP, DBP, HR, and SpO(2) were recorded at the baseline and after completing the following tasks: a Valsalva maneuver, 12 trials using the EMST device, 13 trials using the EMST device, and 5 min of rest following the EMST session. A mixed linear model tested for changes across the six time points. The results indicated no significant change of SBP, DBP, HR, or SpO(2) during or following the EMST trials or after performing the Valsalva maneuver. The results suggest that EMST does not elicit significant fluctuations of blood pressure, HR, and SpO(2) in healthy young adults even when considering the effects of covariates on the outcomes measures.

  16. Surfactant impairment after mechanical ventilation with large alveolar surface area changes and effects of positive end-expiratory pressure

    NARCIS (Netherlands)

    S.J.C. Verbrugge (Serge); S.H. Bohm; D.A.M.P.J. Gommers (Diederik); L.J.I. Zimmermann (Luc); B.F. Lachmann (Burkhard)

    1998-01-01

    textabstractWe have assessed the effects of overinflation on surfactant function and composition in rats undergoing ventilation for 20 min with 100% oxygen at a peak inspiratory pressure of 45 cm H2O, with or without PEEP 10 cm H2O (groups 45/10 and 45/0, respectively).

  17. Changes in Positive End-Expiratory Pressure Alter the Distribution of Ventilation within the Lung Immediately after Birth in Newborn Rabbits

    Science.gov (United States)

    Kitchen, Marcus J.; Siew, Melissa L.; Wallace, Megan J.; Fouras, Andreas; Lewis, Robert A.; Yagi, Naoto; Uesugi, Kentaro; te Pas, Arjan B.; Hooper, Stuart B.

    2014-01-01

    Current recommendations suggest the use of positive end-expiratory pressures (PEEP) to assist very preterm infants to develop a functional residual capacity (FRC) and establish gas exchange at birth. However, maintaining a consistent PEEP is difficult and so the lungs are exposed to changing distending pressures after birth, which can affect respiratory function. Our aim was to determine how changing PEEP levels alters the distribution of ventilation within the lung. Preterm rabbit pups (28 days gestation) were delivered and mechanically ventilated with one of three strategies, whereby PEEP was changed in sequence; 0-5-10-5-0 cmH2O, 5-10-0-5-0 cmH2O or 10-5-0-10-0 cmH2O. Phase contrast X-ray imaging was used to analyse the distribution of ventilation in the upper left (UL), upper right (UR), lower left (LL) and lower right (LR) quadrants of the lung. Initiating ventilation with 10PEEP resulted in a uniform increase in FRC throughout the lung whereas initiating ventilation with 5PEEP or 0PEEP preferentially aerated the UR than both lower quadrants (pventilation at 10PEEP, the distribution of air at end-inflation was uniform across all quadrants and remained so regardless of the PEEP level. Uniform distribution of ventilation can be achieved by initiating ventilation with a high PEEP. After the lungs have aerated, small and stepped reductions in PEEP result in more uniform changes in ventilation. PMID:24690890

  18. The effect of positive-end expiratory pressure on oxygenation during high frequency jet ventilation and conventional mechanical ventilation in the rabbit model of acute lung injury.

    Science.gov (United States)

    Bang, Jae Ouk; Ha, Seung Il; Choi, In-Cheol

    2012-10-01

    The use of positive end expiratory pressure (PEEP) in patients with acute lung injury (ALI) improves arterial oxygenation by alleviating pulmonary shunting, helping the respiratory muscles to decrease the work of breathing, decreasing the rate of infiltrated and atelectatic tissues, and increasing functional residual capacity. In a rabbit model of saline lavage-induced ALI, we examined the effects of PEEP on gas exchange, hemodynamics, and oxygenation during high frequency jet ventilation (HFJV), and then compared these parameters with those during conventional mechanical ventilation (CMV). Twelve rabbits underwent repeated saline lavage to create ALI. The animals were divided in 2 groups: 1) Group CMV (n = 6), and 2) Group HFJV (n = 6). In both groups, we applied 2 levels of PEEP (5 cmH(2)O and 10 cmH(2)O) and then measured the arterial blood gas, mixed venous blood gas, and hemodynamic parameters. With administration of PEEP of either 5 cmH(2)O or 10 cmH(2)O, the arterial oxygen content of both groups was increased, although without statistically significant differences between groups. On the contrary, the arterial carbon dioxide content was significantly decreased in the HFJV group, as compared with the CMV group, during the entire experiment. Furthermore, there was significant decreases in mean arterial pressures in both groups with a PEEP of 10 cmH(2)O. The application of PEEP in rabbits with ALI effectively improves oxygenation in either HFJV or CMV.

  19. Effect of Positive End-Expiratory Pressure on the Sonographic Optic Nerve Sheath Diameter as a Surrogate for Intracranial Pressure during Robot-Assisted Laparoscopic Prostatectomy: A Randomized Controlled Trial.

    Science.gov (United States)

    Chin, Ji-Hyun; Kim, Wook-Jong; Lee, Joonho; Han, Yun A; Lim, Jinwook; Hwang, Jai-Hyun; Cho, Seong-Sik; Kim, Young-Kug

    2017-01-01

    Positive end-expiratory pressure (PEEP) can increase intracranial pressure. Pneumoperitoneum and the Trendelenburg position are associated with an increased intracranial pressure. We investigated whether PEEP ventilation could additionally influence the sonographic optic nerve sheath diameter as a surrogate for intracranial pressure during pneumoperitoneum combined with the Trendelenburg position in patients undergoing robot-assisted laparoscopic prostatectomy. After anesthetic induction, 38 patients were randomly allocated to a low tidal volume ventilation (8 ml/kg) without PEEP group (zero end-expiratory pressure [ZEEP] group, n = 19) or low tidal volume ventilation with 8 cmH2O PEEP group (PEEP group, n = 19). The sonographic optic nerve sheath diameter was measured prior to skin incision, 5 min and 30 min after pneumoperitoneum and the Trendelenburg position, and at the end of surgery. The study endpoint was the difference in the sonographic optic nerve sheath diameter 5 min after pneumoperitoneum and the Trendelenburg position between the ZEEP and PEEP groups. Optic nerve sheath diameters 5 min after pneumoperitoneum and the Trendelenburg position did not significantly differ between the groups [least square mean (95% confidence interval); 4.8 (4.6-4.9) mm vs 4.8 (4.7-5.0) mm, P = 0.618]. Optic nerve sheath diameters 30 min after pneumoperitoneum and the Trendelenburg position also did not differ between the groups [least square mean (95% confidence interval); 4.5 (4.3-4.6) mm vs 4.5 (4.4-4.6) mm, P = 0.733]. An 8 cmH2O PEEP application under low tidal volume ventilation does not induce an increase in the optic nerve sheath diameter during pneumoperitoneum combined with the steep Trendelenburg position, suggesting that there might be no detrimental effects of PEEP on the intracranial pressure during robot-assisted laparoscopic prostatectomy. ClinicalTrial.gov NCT02516566.

  20. Impact of changes of positive end-expiratory pressure on functional residual capacity at low tidal volume ventilation during general anesthesia.

    Science.gov (United States)

    Satoh, Daizoh; Kurosawa, Shin; Kirino, Wakaba; Wagatsuma, Toshihiro; Ejima, Yutaka; Yoshida, Akiko; Toyama, Hiroaki; Nagaya, Kei

    2012-10-01

    Several reports in the literature have described the effects of positive end-expiratory pressure (PEEP) level upon functional residual capacity (FRC) in ventilated patients during general anesthesia. This study compares FRC in mechanically low tidal volume ventilation with different PEEP levels during upper abdominal surgery. Before induction of anesthesia (awake) for nine patients with upper abdominal surgery, a tight-seal facemask was applied with 2 cmH(2)O pressure support ventilation and 100 % O(2) during FRC measurements conducted on patients in a supine position. After tracheal intubation, lungs were ventilated with bilevel airway pressure with a volume guarantee (7 ml/kg predicted body weight) and with an inspired oxygen fraction (FIO(2)) of 0.4. PEEP levels of 0, 5, and 10 cmH(2)O were used. Each level of 5 and 10 cmH(2)O PEEP was maintained for 2 h. FRC was measured at each PEEP level. FRC awake was significantly higher than that at PEEP 0 cmH(2)O (P cmH(2)O was significantly lower than that at 10 cmH(2)O (P cmH(2)O (P cmH(2)O was significantly lower than that for PEEP 5 cmH(2)O or PEEP 10 cmH(2)O (P cmH(2)O, PEEP 5 cmH(2)O after 2 h, and PEEP 10 cmH(2)O after 2 h were correlated with FRC (R = 0.671, P cmH(2)O is necessary to maintain lung function if low tidal volume ventilation is used during upper abdominal surgery.

  1. Variable positive end-expiratory pressure can maintain oxygenation in experimental acute respiratory distress syndrome induced by oleic acid in dogs

    Directory of Open Access Journals (Sweden)

    F.C. Lanza

    2009-08-01

    Full Text Available The use of positive end-expiratory pressure (PEEP or lung recruitment maneuvers (RM to improve oxygenation in acute respiratory distress syndrome (ARDS is used but it may reduce cardiac output (CO. Intermittent PEEP may avoid these complications. Our objective was to determine if variable PEEP compared with constant PEEP is capable of maintaining arterial oxygenation and minimizing hemodynamic alterations with or without RM. Eighteen dogs with ARDS induced by oleic acid were randomized into three equal groups: group 1, low variable PEEP; group 2, high variable PEEP, and group 3, RM + high variable PEEP. All groups were submitted to constant PEEP, followed by variable PEEP (PEEP was increased from 5 to 10 cmH2O in group 1, and from 5 to 18 cmH2O in the other two groups. PaO2 was higher in group 3 (356.2 ± 65.4 mmHg than in group 1 (92.7 ± 29.7 mmHg and group 2 (228.5 ± 72.4 mmHg, P 0.05. Variable PEEP is able to maintain PaO2 when performed in combination with RM in dogs with ARDS. After RM, CO was reduced and there was no relevant difference between the variable and constant PEEP periods.

  2. Capillarity Induced Negative Pressure of Water Plugs in Nanochannels

    NARCIS (Netherlands)

    Tas, Niels Roelof; Mela, P.; Kramer, Tobias; Berenschot, Johan W.; van den Berg, Albert

    2003-01-01

    We have found evidence that water plugs in hydrophilic nanochannels can be at significant negative pressure due to tensile capillary forces. The negative pressure of water plugs in nanochannels induces bending of the thin channel capping layer, which results in a visible curvature of the liquid

  3. 21 CFR 868.5935 - External negative pressure ventilator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External negative pressure ventilator. 868.5935 Section 868.5935 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is a...

  4. [Effects of different levels of end-expiratory pressure on hemodynamic, respiratory mechanics and systemic stress response during laparoscopic cholecystectomy].

    Science.gov (United States)

    Sen, Oznur; Erdogan Doventas, Yasemin

    General anesthesia causes reduction of functional residual capacity. And this decrease can lead to atelectasis and intrapulmonary shunting in the lung. In this study we want to evaluate the effects of 5 and 10cmH 2 O PEEP levels on gas exchange, hemodynamic, respiratory mechanics and systemic stress response in laparoscopic cholecystectomy. American Society of Anesthesiologist I-II physical status 43 patients scheduled for laparoscopic cholecystectomy were randomly selected to receive external PEEP of 5cmH 2 O (PEEP 5 group) or 10cmH 2 O PEEP (PEEP 10 group) during pneumoperitoneum. Basal hemodynamic parameters were recorded, and arterial blood gases (ABG) and blood sampling were done for cortisol, insulin and glucose level estimations to assess the systemic stress response before induction of anesthesia. Thirty minutes after the pneumoperitoneum, the respiratory and hemodynamic parameters were recorded again and ABG and sampling for cortisol, insulin, and glucose levels were repeated. Lastly hemodynamic parameters were recorded; ABG analysis and sampling for stress response levels were taken after 60minutes from extubation. There were no statistical differences between the two groups about hemodynamic and respiratory parameters except mean airway pressure (P mean ). P mean , compliance and PaO 2 ; pH values were higher in 'PEEP 10 group'. Also, PaCO 2 values were lower in 'PEEP 10 group'. No differences were observed between insulin and lactic acid levels in the two groups. But postoperative cortisol level was significantly lower in 'PEEP 10 group'. Ventilation with 10cmH 2 O PEEP increases compliance and oxygenation, does not cause hemodynamic and respiratory complications and reduces the postoperative stress response. Copyright © 2016 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  5. Effects of different levels of end-expiratory pressure on hemodynamic, respiratory mechanics and systemic stress response during laparoscopic cholecystectomy.

    Science.gov (United States)

    Sen, Oznur; Erdogan Doventas, Yasemin

    General anesthesia causes reduction of functional residual capacity. And this decrease can lead to atelectasis and intrapulmonary shunting in the lung. In this study we want to evaluate the effects of 5 and 10cmH 2 O PEEP levels on gas exchange, hemodynamic, respiratory mechanics and systemic stress response in laparoscopic cholecystectomy. American Society of Anesthesiologist I-II physical status 43 patients scheduled for laparoscopic cholecystectomy were randomly selected to receive external PEEP of 5cmH 2 O (PEEP 5 group) or 10cmH 2 O PEEP (PEEP 10 group) during pneumoperitoneum. Basal hemodynamic parameters were recorded, and arterial blood gases (ABG) and blood sampling were done for cortisol, insulin and glucose level estimations to assess the systemic stress response before induction of anesthesia. Thirty minutes after the pneumoperitoneum, the respiratory and hemodynamic parameters were recorded again and ABG and sampling for cortisol, insulin, and glucose levels were repeated. Lastly hemodynamic parameters were recorded; ABG analysis and sampling for stress response levels were taken after 60minutes from extubation. There were no statistical differences between the two groups about hemodynamic and respiratory parameters except mean airway pressure (P mean ). P mean , compliance and PaO 2 ; pH values were higher in 'PEEP 10 group'. Also, PaCO 2 values were lower in 'PEEP 10 group'. No differences were observed between insulin and lactic acid levels in the two groups. But postoperative cortisol level was significantly lower in 'PEEP 10 group'. Ventilation with 10cmH 2 O PEEP increases compliance and oxygenation, does not cause hemodynamic and respiratory complications and reduces the postoperative stress response. Copyright © 2016 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  6. Experimental blunt chest trauma--cardiorespiratory effects of different mechanical ventilation strategies with high positive end-expiratory pressure: a randomized controlled study.

    Science.gov (United States)

    Schreiter, Dierk; Carvalho, Nadja C; Katscher, Sebastian; Mende, Ludger; Reske, Alexander P; Spieth, Peter M; Carvalho, Alysson R; Beda, Alessandro; Lachmann, Burkhard; Amato, Marcelo B P; Wrigge, Hermann; Reske, Andreas W

    2016-01-12

    Uncertainty persists regarding the optimal ventilatory strategy in trauma patients developing acute respiratory distress syndrome (ARDS). This work aims to assess the effects of two mechanical ventilation strategies with high positive end-expiratory pressure (PEEP) in experimental ARDS following blunt chest trauma. Twenty-six juvenile pigs were anesthetized, tracheotomized and mechanically ventilated. A contusion was applied to the right chest using a bolt-shot device. Ninety minutes after contusion, animals were randomized to two different ventilation modes, applied for 24 h: Twelve pigs received conventional pressure-controlled ventilation with moderately low tidal volumes (VT, 8 ml/kg) and empirically chosen high external PEEP (16 cmH2O) and are referred to as the HP-CMV-group. The other group (n = 14) underwent high-frequency inverse-ratio pressure-controlled ventilation (HFPPV) involving respiratory rate of 65 breaths · min(-1), inspiratory-to-expiratory-ratio 2:1, development of intrinsic PEEP and recruitment maneuvers, compatible with the rationale of the Open Lung Concept. Hemodynamics, gas exchange and respiratory mechanics were monitored during 24 h. Computed tomography and histology were analyzed in subgroups. Comparing changes which occurred from randomization (90 min after chest trauma) over the 24-h treatment period, groups differed statistically significantly (all P values for group effect <0.001, General Linear Model analysis) for the following parameters (values are mean ± SD for randomization vs. 24-h): PaO2 (100% O2) (HFPPV 186 ± 82 vs. 450 ± 59 mmHg; HP-CMV 249 ± 73 vs. 243 ± 81 mmHg), venous admixture (HFPPV 34 ± 9.8 vs. 11.2 ± 3.7%; HP-CMV 33.9 ± 10.5 vs. 21.8 ± 7.2%), PaCO2 (HFPPV 46.9 ± 6.8 vs. 33.1 ± 2.4 mmHg; HP-CMV 46.3 ± 11.9 vs. 59.7 ± 18.3 mmHg) and normally aerated lung mass (HFPPV 42.8 ± 11.8 vs. 74.6 ± 10.0 %; HP-CMV 40.7 ± 8.6 vs. 53.4 ± 11.6%). Improvements occurring after recruitment in the HFPPV-group persisted

  7. Changes in positive end-expiratory pressure alter the distribution of ventilation within the lung immediately after birth in newborn rabbits.

    Directory of Open Access Journals (Sweden)

    Marcus J Kitchen

    Full Text Available Current recommendations suggest the use of positive end-expiratory pressures (PEEP to assist very preterm infants to develop a functional residual capacity (FRC and establish gas exchange at birth. However, maintaining a consistent PEEP is difficult and so the lungs are exposed to changing distending pressures after birth, which can affect respiratory function. Our aim was to determine how changing PEEP levels alters the distribution of ventilation within the lung. Preterm rabbit pups (28 days gestation were delivered and mechanically ventilated with one of three strategies, whereby PEEP was changed in sequence; 0-5-10-5-0 cmH2O, 5-10-0-5-0 cmH2O or 10-5-0-10-0 cmH2O. Phase contrast X-ray imaging was used to analyse the distribution of ventilation in the upper left (UL, upper right (UR, lower left (LL and lower right (LR quadrants of the lung. Initiating ventilation with 10PEEP resulted in a uniform increase in FRC throughout the lung whereas initiating ventilation with 5PEEP or 0PEEP preferentially aerated the UR than both lower quadrants (p<0.05. Consequently, the relative distribution of incoming VT was preferentially directed into the lower lobes at low PEEP, primarily due to the loss of FRC in those lobes. Following ventilation at 10PEEP, the distribution of air at end-inflation was uniform across all quadrants and remained so regardless of the PEEP level. Uniform distribution of ventilation can be achieved by initiating ventilation with a high PEEP. After the lungs have aerated, small and stepped reductions in PEEP result in more uniform changes in ventilation.

  8. Effects of positive end-expiratory pressure titration and recruitment maneuver on lung inflammation and hyperinflation in experimental acid aspiration-induced lung injury.

    Science.gov (United States)

    Ambrosio, Aline M; Luo, Rubin; Fantoni, Denise T; Gutierres, Claudia; Lu, Qin; Gu, Wen-Jie; Otsuki, Denise A; Malbouisson, Luiz M S; Auler, Jose O C; Rouby, Jean-Jacques

    2012-12-01

    In acute lung injury positive end-expiratory pressure (PEEP) and recruitment maneuver are proposed to optimize arterial oxygenation. The aim of the study was to evaluate the impact of such a strategy on lung histological inflammation and hyperinflation in pigs with acid aspiration-induced lung injury. Forty-seven pigs were randomly allocated in seven groups: (1) controls spontaneously breathing; (2) without lung injury, PEEP 5 cm H2O; (3) without lung injury, PEEP titration; (4) without lung injury, PEEP titration + recruitment maneuver; (5) with lung injury, PEEP 5 cm H2O; (6) with lung injury, PEEP titration; and (7) with lung injury, PEEP titration + recruitment maneuver. Acute lung injury was induced by intratracheal instillation of hydrochloric acid. PEEP titration was performed by incremental and decremental PEEP from 5 to 20 cm H2O for optimizing arterial oxygenation. Three recruitment maneuvers (pressure of 40 cm H2O maintained for 20 s) were applied to the assigned groups at each PEEP level. Proportion of lung inflammation, hemorrhage, edema, and alveolar wall disruption were recorded on each histological field. Mean alveolar area was measured in the aerated lung regions. Acid aspiration increased mean alveolar area and produced alveolar wall disruption, lung edema, alveolar hemorrhage, and lung inflammation. PEEP titration significantly improved arterial oxygenation but simultaneously increased lung inflammation in juxta-diaphragmatic lung regions. Recruitment maneuver during PEEP titration did not induce additional increase in lung inflammation and alveolar hyperinflation. In a porcine model of acid aspiration-induced lung injury, PEEP titration aimed at optimizing arterial oxygenation, substantially increased lung inflammation. Recruitment maneuvers further improved arterial oxygenation without additional effects on inflammation and hyperinflation.

  9. Pressure Field Around Underwater Negative Streamers

    Czech Academy of Sciences Publication Activity Database

    Hoffer, Petr; Koláček, Karel; Lukeš, Petr; Stelmashuk, Vitaliy

    2015-01-01

    Roč. 43, č. 5 (2015), s. 1787-1792 ISSN 0093-3813 R&D Projects: GA ČR(CZ) GA15-12987S Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100431203 Program:M Institutional support: RVO:61389021 Keywords : Interferometry * plasma generation * pressure measurement * water Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.958, year: 2015

  10. Influência da técnica de pressão expiratória positiva oscilante utilizando pressões expiratórias pré-determinadas na viscosidade e na transportabilidade do escarro em pacientes com bronquiectasia Influence that oscillating positive expiratory pressure using predetermined expiratory pressures has on the viscosity and transportability of sputum in patients with bronchiectasis

    Directory of Open Access Journals (Sweden)

    Ercy Mara Cipulo Ramos

    2009-12-01

    Full Text Available OBJETIVO: Verificar a efetividade da técnica de pressão expiratória positiva oscilante (PEPO utilizando pressões expiratórias pré-determinadas sobre a viscosidade e a transportabilidade do escarro em pacientes com bronquiectasia. MÉTODOS: Foram incluídos no estudo 15 pacientes estáveis com bronquiectasia (7 homens; média de idade = 53 ± 16 anos, submetidos a duas intervenções PEPO consecutivas, com 24 h de intervalo entre si, utilizando pressões expiratórias de 15 cmH2O (P15 e 25 cmH2O (P25. O protocolo consistiu de tosse voluntária; nova expectoração voluntária após 20 min, denominado tempo zero (T0; repouso de 10 min; e utilização da técnica em duas séries de 10 min (S1 e S2 de PEPO em P15 e P25, com intervalo de 10 min entre si. A viscosidade e transportabilidade do escarro foram avaliadas pela viscosimetria, velocidade relativa de transporte no palato de rã, deslocamento em máquina simuladora de tosse e ângulo de adesão. As amostras de escarro foram coletadas em T0, após S1 e após S2. Testes estatísticos específicos foram aplicados de acordo com a distribuição dos dados. RESULTADOS: Houve diminuição significante da viscosidade do escarro após S1 em P15 e após S2 em P25. Não houve diferenças significantes entre todas as amostras para a transportabilidade. CONCLUSÕES: Houve diminuição da viscosidade do escarro quando a PEPO foi realizada em P15 e P25, o que sugere que não seja necessário gerar alta pressão expiratória para obter o resultado desejado.OBJECTIVE: To determine the effectiveness of oscillating positive expiratory pressure (OPEP using predetermined expiratory pressures on the viscosity and transportability of sputum in patients with bronchiectasis. METHODS: The study involved 15 stable patients with bronchiectasis (7 males; mean age = 53 ± 16 years, submitted to two consecutive OPEP interventions, with a 24-h interval between the two, using positive expiratory pressures set at 15 cmH2O

  11. Positive end expiratory pressure during one-lung ventilation: Selecting ideal patients and ventilator settings with the aim of improving arterial oxygenation

    Directory of Open Access Journals (Sweden)

    Hoftman Nir

    2011-01-01

    Full Text Available The efficacy of positive end-expiratory pressure (PEEP in treating intraoperative hypoxemia during one-lung ventilation (OLV remains in question given conflicting results of prior studies. This study aims to (1 evaluate the efficacy of PEEP during OLV, (2 assess the utility of preoperative predictors of response to PEEP, and (3 explore optimal intraoperative settings that would maximize the effects of PEEP on oxygenation. Forty-one thoracic surgery patients from a single tertiary care university center were prospectively enrolled in this observational study. After induction of general anesthesia, a double-lumen endotracheal tube was fiberoptically positioned and OLV initiated. Intraoperatively, PEEP = 5 and 10 cmH 2 O were sequentially applied to the ventilated lung during OLV. Arterial oxygenation, cardiovascular performance parameters, and proposed perioperative variables that could predict or enhance response to PEEP were analysed. T-test and c2 tests were utilized for continuous and categorical variables, respectively. Multivariate analyses were carried out using a classification tree model of binary recursive partitioning. PEEP improved arterial oxygenation by ≥20% in 29% of patients (n = 12 and failed to do so in 71% (n = 29; however, no cardiovascular impact was noted. Among the proposed clinical predictors, only intraoperative tidal volume per kilogram differed significantly between responders to PEEP and non-responders (mean 6.6 vs. 5.7 ml/kg, P = 0.013; no preoperative variable predicted response to PEEP. A multivariate analysis did not yield a clinically significant model for predicting PEEP responsiveness. PEEP improved oxygenation in a subset of patients; larger, although still protective tidal volumes favored a positive response to PEEP. No preoperative variables, however, could be identified as reliable predictors for PEEP responders.

  12. Effects of positive expiratory pressure on pulmonary clearance of aerosolized technetium-{sup 99m}-labeled diethylenetriaminepentaacetic acid in healthy individuals

    Energy Technology Data Exchange (ETDEWEB)

    Albuquerque, Isabella Martins de, E-mail: albuisa@gmail.com [Universidade Federal de Santa Maria (UFSM), Santa Maria, RS (Brazil). Departamento de Fisioterapia e Reabilitacao; Cardoso, Dannuey Machado; Paiva, Dulciane Nunes [Universidade de Santa Cruz do Sul, RS (Brazil); Masiero, Paulo Ricardo; Menna-Barreto, Sergio Saldanha [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre (Brazil); Resqueti, Vanessa Regiane; Fregonezi, Guilherme Augusto de Freitas [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2016-11-15

    Objective: To evaluate the effects of positive expiratory pressure (PEP) on pulmonary epithelial membrane permeability in healthy subjects. Methods: We evaluated a cohort of 30 healthy subjects (15 males and 15 females) with a mean age of 28.3 ± 5.4 years, a mean FEV{sub 1}/FVC ratio of 0.89 ± 0.14, and a mean FEV{sub 1} of 98.5 ± 13.1% of predicted. Subjects underwent technetium-99m labeled diethylenetriaminepentaacetic acid ({sup 99m}TcDTPA) radio aerosol inhalation lung scintigraphy in two stages: during spontaneous breathing; and while breathing through a PEP mask at one of three PEP levels—10 cmH{sub 2}O (n = 10), 15 cmH{sub 2}O (n = 10), and 20 cmH{sub 2}O (n = 10). The {sup 99m}Tc-DTPA was nebulized for 3 min, and its clearance was recorded by scintigraphy over a 30-min period during spontaneous breathing and over a 30-min period during breathing through a PEP mask. Results: The pulmonary clearance of {sup 99m}Tc-DTPA was significantly shorter when PEP was applied—at 10 cmH{sub 2}O (p = 0.044), 15 cmH{sub 2}O (p = 0.044), and 20 cmH{sub 2}O (p = 0.004) - in comparison with that observed during spontaneous breathing. Conclusions: Our findings indicate that PEP, at the levels tested, is able to induce an increase in pulmonary epithelial membrane permeability and lung volume in healthy subjects. (author)

  13. Effects of positive end-expiratory pressure and 30% inspired oxygen on pulmonary mechanics and atelectasis in cats undergoing non-bronchoscopic bronchoalveolar lavage.

    Science.gov (United States)

    Bernhard, Christa; Masseau, Isabelle; Dodam, John; Outi, Hilton; Krumme, Stacy; Bishop, Kaitlin; Graham, Amber; Reinero, Carol

    2017-06-01

    Objectives The objective of this study was to determine if modification of inspired oxygen concentration or positive end-expiratory pressure (PEEP) would alter bronchoalveolar lavage (BAL)-induced changes in pulmonary mechanics or atelectasis, as measured using ventilator-acquired pulmonary mechanics and thoracic CT. Methods Six experimentally asthmatic cats underwent anesthesia and non-bronchoscopic BAL, each under four randomized treatment conditions: 100% oxygen, zero PEEP; 30% oxygen, zero PEEP; 100% oxygen, PEEP 2 cmH 2 O; and 30% oxygen, PEEP 2 cmH 2 O. Pulse oximetry was used to estimate oxygen saturation (SpO 2 ). Ventilator-acquired pulmonary mechanics and thoracic CT scans were collected prior to BAL and at 1, 5 and 15 mins post-BAL. Results While receiving 100% oxygen, no cat had SpO 2 90% by 1 min later. There was a significant increase in airway resistance and a decrease in lung compliance following BAL, but there was no significant difference between treatment groups. Cats receiving no PEEP and 30% oxygen conserved better aeration of the lung parenchyma in BAL-sampled areas than those receiving no PEEP and 100% oxygen. Conclusions and relevance Alterations in pulmonary mechanics or atelectasis may not be reflected by SpO 2 following BAL. The use of 30% inspired oxygen concentration failed to show any significant improvement in pulmonary mechanics but did diminish atelectasis. In some cats, it was also associated with desaturation of hemoglobin. The use of PEEP in this study did not show any effect on our outcome parameters. Further studies using higher PEEP (5-10 cmH 2 O) and intermediate inspired oxygen concentration (40-60%) are warranted to determine if they would confer clinical benefit in cats undergoing diagnostic BAL.

  14. Respiratory effects of low versus high tidal volume with or without positive end-expiratory pressure in anesthetized dogs with healthy lungs.

    Science.gov (United States)

    De Monte, Valentina; Bufalari, Antonello; Grasso, Salvatore; Ferrulli, Fabienne; Crovace, Alberto Maria; Lacitignola, Luca; Staffieri, Francesco

    2018-05-01

    OBJECTIVE To evaluate the impact of 2 tidal volumes (T V s) with or without positive end-expiratory pressure (PEEP) on lung mechanics, aeration, and gas exchange in healthy anesthetized dogs. ANIMALS 40 mixed-breed dogs with healthy lungs. PROCEDURES Anesthetized dogs were randomly assigned to 4 groups (n = 10/group) with different ventilatory settings: T V of 8 mL/kg and PEEP of 0 cm H 2 O (low T V group), T V of 8 mL/kg and PEEP of 5 cm H 2 O (low T V plus PEEP group), T V of 15 mL/kg and PEEP of 0 cm H 2 O (high T V group), or T V of 15 mL/kg and PEEP of 5 cm H 2 O (high T V plus PEEP group). Expired CO 2 and respiratory rate were titrated on the basis of a predetermined stepwise protocol. Gas exchange, respiratory mechanics, and pulmonary aeration were evaluated by means of CT 30 minutes after starting mechanical ventilation at the assigned setting. RESULTS Partial pressures of arterial and expired CO 2 were higher in the low T V and low T V plus PEEP groups than in the high T V and high T V plus PEEP groups. Peak and plateau airway pressures were higher in the PEEP group than in the other groups. Static lung compliance was higher in the high T V plus PEEP group than in the low T V group. Relative percentages of atelectatic and poorly aerated lung were lower in the high T V plus PEEP group than in the other groups. Oxygenation was similar among groups. CONCLUSIONS AND CLINICAL RELEVANCE Differences in T V and PEEP application during mechanical ventilation may affect respiratory function in anesthetized dogs with healthy lungs. Ventilation with a T V of 15 mL/kg and PEEP of 5 cm H 2 O significantly improved lung compliance and reduced the amount of atelectatic and poorly aerated lung.

  15. Alveolar Tidal recruitment/derecruitment and Overdistension During Four Levels of End-Expiratory Pressure with Protective Tidal Volume During Anesthesia in a Murine Lung-Healthy Model.

    Science.gov (United States)

    Soares, Joao Henrique Neves; Carvalho, Alysson Roncally; Bergamini, Bruno Curty; Gress, Maria Alice Kuster; Jandre, Frederico Caetano; Zin, Walter Araujo; Giannella-Neto, Antonio

    2018-02-12

    We compared respiratory mechanics between the positive end-expiratory pressure of minimal respiratory system elastance (PEEP minErs ) and three levels of PEEP during low-tidal-volume (6 mL/kg) ventilation in rats. Twenty-four rats were anesthetized, paralyzed, and mechanically ventilated. Airway pressure (P aw ), flow (F), and volume (V) were fitted by a linear single compartment model (LSCM) P aw (t) = E rs  × V(t) + R rs  × F(t) + PEEP or a volume- and flow-dependent SCM (VFDSCM) P aw (t) = (E 1  + E 2  × V(t)) × V(t) + (K 1  + K 2  × |F(t)|) × F(t) + PEEP, where E rs and R rs are respiratory system elastance and resistance, respectively; E 1 and E 2 × V are volume-independent and volume-dependent E rs , respectively; and K 1 and K 2  × F are flow-independent and flow-dependent R rs , respectively. Animals were ventilated for 1 h at PEEP 0 cmH 2 O (ZEEP); PEEP minErs ; 2 cmH 2 O above PEEP minErs (PEEP minErs+2 ); or 4 cmH 2 O above PEEP minErs (PEEP minErs+4 ). Alveolar tidal recruitment/derecruitment and overdistension were assessed by the index %E 2  = 100 × [(E 2  × V T )/(E 1  + |E 2 | × V T )], and alveolar stability by the slope of E rs (t). %E 2 varied between 0 and 30% at PEEP minErs in most respiratory cycles. Alveolar Tidal recruitment/derecruitment (%E 2   30) were predominant in the absence of PEEP and in PEEP levels higher than PEEP minErs , respectively. The slope of E rs (t) was different from zero in all groups besides PEEP minErs+4 . PEEP minErs presented the best compromise between alveolar tidal recruitment/derecruitment and overdistension, during 1 h of low-V T mechanical ventilation.

  16. Negative pressure ventilation enhances acinar perfusion in isolated rat lungs.

    Science.gov (United States)

    Watson, Kal E; Segal, Gilad S; Conhaim, Robert L

    2018-01-01

    We compared acinar perfusion in isolated rat lungs ventilated using positive or negative pressures. The lungs were ventilated with air at transpulmomary pressures of 15/5 cm H 2 O, at 25 breaths/min, and perfused with a hetastarch solution at P pulm art /P LA pressures of 10/0 cm H 2 O. We evaluated overall perfusability from perfusate flows, and from the venous concentrations of 4-µm diameter fluorescent latex particles infused into the pulmonary circulation during perfusion. We measured perfusion distribution from the trapping patterns of those particles within the lung. We infused approximately 9 million red fluorescent particles into each lung, followed 20 min later by an infusion of an equal number of green particles. In positive pressure lungs, 94.7 ± 2.4% of the infused particles remained trapped within the lungs, compared to 86.8 ± 5.6% in negative pressure lungs ( P ≤ 0.05). Perfusate flows averaged 2.5 ± 0.1 mL/min in lungs ventilated with positive pressures, compared to 5.6 ± 01 mL/min in lungs ventilated with negative pressures ( P ≤ 0.05). Particle infusions had little effect on perfusate flows. In confocal images of dried sections of each lung, red and green particles were co-localized in clusters in positive pressure lungs, suggesting that acinar vessels that lacked particles were collapsed by these pressures thereby preventing perfusion through them. Particles were more broadly and uniformly distributed in negative pressure lungs, suggesting that perfusion in these lungs was also more uniformly distributed. Our results suggest that the acinar circulation is organized as a web, and further suggest that portions of this web are collapsed by positive pressure ventilation.

  17. Negative pressure pulmonary edema revisited: Pathophysiology and review of management

    Directory of Open Access Journals (Sweden)

    Balu Bhaskar

    2011-01-01

    Full Text Available Negative pressure pulmonary edema (NPPE is a dangerous and potentially fatal condition with a multifactorial pathogenesis. Frequently, NPPE is a manifestation of upper airway obstruction, the large negative intrathoracic pressure generated by forced inspiration against an obstructed airway is thought to be the principal mechanism involved. This negative pressure leads to an increase in pulmonary vascular volume and pulmonary capillary transmural pressure, creating a risk of disruption of the alveolar-capillary membrane. The early detection of the signs of this syndrome is vital to the treatment and to patient outcome. The purpose of this review is to highlight the available literature on NPPE, while probing the pathophysiological mechanisms relevant in both the development of this condition and that involved in its resolution.

  18. Negative pressure characteristics of an evaporating meniscus at nanoscale

    Directory of Open Access Journals (Sweden)

    Maroo Shalabh

    2011-01-01

    Full Text Available Abstract This study aims at understanding the characteristics of negative liquid pressures at the nanoscale using molecular dynamics simulation. A nano-meniscus is formed by placing liquid argon on a platinum wall between two nano-channels filled with the same liquid. Evaporation is simulated in the meniscus by increasing the temperature of the platinum wall for two different cases. Non-evaporating films are obtained at the center of the meniscus. The liquid film in the non-evaporating and adjacent regions is found to be under high absolute negative pressures. Cavitation cannot occur in these regions as the capillary height is smaller than the critical cavitation radius. Factors which determine the critical film thickness for rupture are discussed. Thus, high negative liquid pressures can be stable at the nanoscale, and utilized to create passive pumping devices as well as significantly enhance heat transfer rates.

  19. An Affordable Custom-Built Negative Pressure Wound Therapy

    African Journals Online (AJOL)

    Negative pressure wound therapy (NPWT) is a well- established modality for treating complex wounds (1). There are several proposed mechanisms of action of. NPWT (2). The main disadvantage of NPWT is that it is expensive, a drawback that makes this modality of treatment not available in limited-resources countries.

  20. An Affordable Custom-Built Negative Pressure Wound Therapy ...

    African Journals Online (AJOL)

    Negative pressure wound therapy (NPWT) is a wellestablished and effective method for treating complex wounds. However, this modality of treatment may not be available in limited resource countries due to the high cost. We describe a simple and cheap method of NPWT using gauze swabs, a naso-gastric tube, adhesive ...

  1. Experience with the use of negative pressure bolster dressing for ...

    African Journals Online (AJOL)

    Methodology: This was a prospective study of consecutive patients from January 2009 to December 2010, with wounds over uneven and highly mobile anatomic regions that had their skin grafts stabilized using negative pressure wound dressing. Data on patients' age, sex, region of the body that was skin grafted, size of ...

  2. Negative pressure treatment for necrotizing fasciitis after chemotherapy

    Directory of Open Access Journals (Sweden)

    Fraia Melchionda

    2011-12-01

    Full Text Available We describe 2 cases of children with malignant disease who developed severe mucositis with perineal necrotizing fasciitis during severe neutropenia after chemotherapy. Treatment with topical negative pressure therapy with silver foam dressing, together with large spectrum antibiotics, resolved the problem with complete closure of the wound after 30 and 36 days of treatment, respectively.

  3. Controlling a negative loaded hydraulic cylinder using pressure feedback

    DEFF Research Database (Denmark)

    Hansen, M.R.; Andersen, T.O.

    2010-01-01

    This paper is concerned with the inherent oscillatory nature of pressure compensated velocity control of a hydraulic cylinder subjected to a negative load and suspended by means of an over-center valve. Initially, a linearized stability analysis of such a hydraulic circuit is carried out clearly ...... in a nonlinear time domain simulation model validating the linear stability analysis....

  4. Negative interstitial pressure in the peritendinous region during exercise

    DEFF Research Database (Denmark)

    Langberg, Henning; Skovgaard, D; Bülow, J

    1999-01-01

    of these observations, microdialysis was performed in the peritendinous region with a colloid osmotic active substance (Dextran 70, 0.1 g/ml) added to the perfusate with the aim of counteracting the negative tissue pressure. Dialysate volume was found to be fully restored (100 +/- 4%) during exercise. It is concluded......In the present study, tissue pressure in the peritendinous area ventral to the human Achilles tendon was determined. The pressure was measured during rest and intermittent isometric calf muscle exercise at three torques (56, 112, and 168 Nm) 20, 40 and 50 mm proximal to the insertion of the tendon...... in 11 healthy, young individuals. In all experiments a linear significant decrease in pressure was obtained with increasing torque [e.g., at 40 mm: -0.4 +/- 0.3 mmHg (rest) to -135 +/- 12 mmHg (168 Nm)]. No significant differences were obtained among the three areas measured. On the basis...

  5. Rapid Onset Acute Epiglottitis Leading to Negative Pressure Pulmonary Edema

    Directory of Open Access Journals (Sweden)

    V Saraswat

    2007-01-01

    Full Text Available Pulmonary edema is a potentially life-threatening complication of acute airway obstruction. It develops rapidly, without warning, in young healthy individuals. Two forms of post-obstructive pulmonary edema (POPE (also known as negative pressure pulmonary edema, NPPE have been identified. POPE I follows sudden, severe upper airway obstruction. POPE II occurs following surgical relief of chronic upper airway obstruction. Treatment for both is supportive. Full and rapid recovery can be expected with appropriate management. A case report of a middle aged man with acute onset epiglottitis who developed negative pressure pulmonary edema after intubation is presented. The report includes a brief discussion on etiology, clinical features and management dilemma of acute upper airway obstruction.

  6. Proposed application of lower body negative pressure to cardiology

    Science.gov (United States)

    Schmidt, E. V.; Debusk, R. F.; Popp, R. L.

    1975-01-01

    Potential medical applications are presented of lower body negative pressure to the evaluation and treatment of cardiac patients. The essential features of an LBNP unit and the basic cardiovascular physiology of lower body negative pressure (LBNP) testing are described. Some of the results of previous spaceflight experiences and bedrest studies are summarized. The deconditioning effects of weightlessness experienced by orbiting astronauts are compared with the effects of bedrest restrictions prescribed for convalescing cardiac patients. The potential of LBNP for evaluating both pharmacological and physical activity regimens was examined, particularly in relation to post-myocardial infarction and coronary artery bypass patients. Applications of LBNP to the cardiac catheterization laboratory and the out-patient follow-up of cardiac patients are proposed.

  7. Rapid Onset Acute Epiglottitis Leading to Negative Pressure Pulmonary Edema

    OpenAIRE

    V Saraswat; P V Madhu; Suresh S Kumar

    2007-01-01

    Pulmonary edema is a potentially life-threatening complication of acute airway obstruction. It develops rapidly, without warning, in young healthy individuals. Two forms of post-obstructive pulmonary edema (POPE) (also known as negative pressure pulmonary edema, NPPE) have been identified. POPE I follows sudden, severe upper airway obstruction. POPE II occurs following surgical relief of chronic upper airway obstruction. Treatment for both is supportive. Full and rapid recovery can be expecte...

  8. Negative chemical pressure effects induced by Y substitution for Ca ...

    Indian Academy of Sciences (India)

    Negative chemical pressure effects on Ca3Co2O6. Figure 3. Inverse of magnetic susceptibility (χ) as a function of tempera- ture (30–300 K) for Ca3−xYxCo2O6, obtained in a field of 5 kOe. A straight line is drawn through the high-temperature linear region to highlight the x-dependence of θp. The low-temperature data ...

  9. Negative-pressure wound therapy with instillation: international consensus guidelines.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Steinberg, John S; Evans, Karen K; Lehner, Burkhard; Willy, Christian; Lavery, Larry; Wolvos, Tom; Orgill, Dennis; Ennis, William; Lantis, John; Gabriel, Allen; Schultz, Gregory

    2013-12-01

    Negative-pressure wound therapy with instillation is increasingly utilized as an adjunct therapy for a wide variety of wounds. Despite its growing popularity, there is a paucity of evidence and lack of guidance to provide effective use of this therapy. A panel of experts was convened to provide guidance regarding the appropriate use of negative-pressure wound therapy with instillation. A face-to-face meeting was held where the available evidence was discussed and individual clinical experience with this therapy was shared. Follow-up communication among the panelists continued until consensus was achieved. The final consensus recommendations were derived through more than 80 percent agreement among the panelists. Nine consensus statements were generated that address the appropriate use of negative-pressure wound therapy with instillation. The question of clinical effectiveness of this therapy was not directly addressed by the consensus panel. This document serves as preliminary guidelines until more robust evidence emerges that will support or modify these consensus recommendations.

  10. Perceived social pressure not to experience negative emotion is linked to selective attention for negative information.

    Science.gov (United States)

    Bastian, Brock; Pe, Madeline Lee; Kuppens, Peter

    2017-02-01

    Social norms and values may be important predictors of how people engage with and regulate their negative emotional experiences. Previous research has shown that social expectancies (the perceived social pressure not to feel negative emotion (NE)) exacerbate feelings of sadness. In the current research, we examined whether social expectancies may be linked to how people process emotional information. Using a modified classical flanker task involving emotional rather than non-emotional stimuli, we found that, for those who experienced low levels of NE, social expectancies were linked to the selective avoidance of negative emotional information. Those who experienced high levels of NE did not show a selective avoidance of negative emotional information. The findings suggest that, for people who experience many NEs, social expectancies may lead to discrepancies between how they think they ought to feel and the kind of emotional information they pay attention to.

  11. An anesthetic management of negative pressure pulmonary edema

    Directory of Open Access Journals (Sweden)

    Dipti Raj

    2016-01-01

    Full Text Available Negative pressure pulmonary edema (NPPE is one of the common complications of upper airway obstruction seen by anesthesiologist during either in induction or emergence sometimes both. Patients who have experienced NPPE are generally healthy without comorbidities. NPPE is a result of marked decrease in intrathoracic pressure caused by ventilator efforts against a closed glottis resulting in disruption of normal intravascular Starling mechanism, leading to transudation of intravascular protein, and fluids into the pulmonary interstitium. The onset of NPPE is usually rapid and without prompt recognition and intervention, the outcome can be fatal. This case report is of a 40-year-old female adult, who underwent right-sided percutaneous nephrolithotomy for stone in the right kidney otherwise uncomplicated surgical procedure.

  12. Cardiovascular responses of women to lower body negative pressure

    Science.gov (United States)

    Frey, M. A. B.; Mathes, K. L.; Hoffler, G. W.

    1986-01-01

    The effects of lower body negative pressure (LBNP) on the cardiovascular response of 20 women between 23-43 years are evaluated. Calf circumference and cardiovascular data were recorded for women in the follicular and luteal phases of the menstrual cycle at -30, -40, and -50 mm Hg LBNP. The data reveal that the two menstrual phases did not cause differences in the way women respond to LBNP. It is observed that during LBNP calf circumference is enlarged; transthoracic impedance, and heart rate are increased; stroke volume, left ventricular ejection time, the Heather Index of contractility and systolic pressure, and cardiac output are reduced; and total peripheral resistance is elevated. The experimental data are compared to Montgomery et al. (1979). It is noted that the response of women to -50 mm Hg LBNP is similar to that of men; however, women adapt to stresses on the cardiovascular system with greater heart rate adjustments.

  13. Study on the hydrogen negative ion in low pressure discharges

    International Nuclear Information System (INIS)

    Bruneteau, A.M.

    1983-07-01

    A new use of negative hydrogen ions is the production of intense fast neutral atom beams useful in plasma heating in thermonuclear heating. That is one of the reasons that started this study. The density of negative hydrogen ions in diffusion, and multipole-type low pressure (10 -3 - 10-2 Torr) discharges is deduced from the various formation and destruction processes of the species present in these discharges. The H - ions are essentially produced by dissociative attachment to vibrationally excited molecules and destroyed by processes the relative importance of which is discussed as a function of the discharge parameters. The experimental study of the density of the H - ions, measured by photodetachment, as a function of these parameters, coroborates the theoretical model [fr

  14. Dynamic isolation technologies in negative pressure isolation wards

    CERN Document Server

    Xu, Zhonglin

    2017-01-01

    This book presents novel design principles and technologies for dynamic isolation based on experimental studies. These approaches have now become the local standard in Beijing and are currently being promoted for use nationwide. Further, the book provides details of measures and guidelines for the design process. Departing from the traditional understanding that isolation wards should be designed with high negative pressure, airtight doors and fresh air, it establishes the basis for designing biological clean rooms, including isolation wards, using a simple and convenient scientific approach. This book is intended for designers, engineers, researchers, hospital management staff and graduate students in heating ventilation air conditioning (HVAC), air cleaning technologies and related areas.

  15. Negative pressure pulmonary edema in healthy cosmetic surgery patients.

    Science.gov (United States)

    Dieu, Tam; Upjohn, Edward

    2003-01-01

    Anesthetic complications are uncommon in young and healthy patients undergoing cosmetic surgery. We report 2 cases of negative pressure pulmonary edema (NPPE) in young patients, 1 who underwent rhinoplasty and another who underwent augmentation mammaplasty and suction-assisted lipoplasty of the thighs and buttocks This rare and potentially fatal complication requires admission to an intensive-care unit and delayed discharge. Although cases of NPPE have been reported in the medical and anesthetic literature, NPPE in plastic surgery has never been reported previously.

  16. Solvation pressure as real pressure: I. Ethanol and starch under negative pressure

    CERN Document Server

    Uden, N W A V; Faux, D A; Tanczos, A C; Howlin, B; Dunstan, D J

    2003-01-01

    The reality of the solvation pressure generated by the cohesive energy density of liquids is demonstrated by three methods. Firstly, the Raman spectrum of ethanol as a function of cohesive energy density (solvation pressure) in ethanol-water and ethanol-chloroform mixtures is compared with the Raman spectrum of pure ethanol under external hydrostatic pressure and the solvation pressure and hydrostatic pressure are found to be equivalent for some transitions. Secondly, the bond lengths of ethanol are calculated by molecular dynamics modelling for liquid ethanol under pressure and for ethanol vapour. The difference in bond lengths between vapour and liquid are found to be equivalent to the solvation pressure for the C-H sub 3 , C-H sub 2 and O-H bond lengths, with discrepancies for the C-C and C-O bond lengths. Thirdly, the pressure-induced gelation of potato starch is measured in pure water and in mixtures of water and ethanol. The phase transition pressure varies in accordance with the change in solvation pre...

  17. Apical Negative Pressure irrigation presents tissue compatibility in immature teeth

    Directory of Open Access Journals (Sweden)

    Carolina Maschietto Pucinelli

    Full Text Available Abstract Aim: To compare the apical negative pressure irrigation (ANP with conventional irrigation in the teeth of immature dogs with apical periodontitis. Methods: Fifty-two immature pre-molar root canals were randomly assigned into 4 groups: ANP (n=15; conventional irrigation (n=17; healthy teeth (control (n = 10; and teeth with untreated apical periodontitis (control (n=10. After induction of apical periodontitis, teeth were instrumented using EndoVac® (apical negative pressure irrigation or conventional irrigation. The animals were euthanized after 90 days. The sections were stained by HE and analyzed under conventional and fluorescence microscopy. TRAP histoenzymology was also performed. Statistical analyses were performed with the significance level set at 5%. Results: There was difference in the histopathological parameters between ANP and conventional groups (p0.05. However, a lower number of osteoclasts was observed in the ANP group (p<0.05. Conclusion: The EndoVac® irrigation system presented better biological results and more advanced repair process in immature teeth with apical periodontitis than the conventional irrigation system, confirming the hypothesis.

  18. Management of Pharyngocutaneous Fistula With Negative-Pressure Wound Therapy.

    Science.gov (United States)

    Teixeira, Sérgio; Costa, Joana; Bartosch, Isabel; Correia, Bernardo; Silva, Álvaro

    2017-06-01

    Pharyngocutaneous fistula is a common complication of laryngopharyngeal surgery and is associated with increased morbidity and mortality. Beyond the classical management, negative-pressure wound therapy (NPWT) can be an alternative and effective treatment. Two patients with pT3N0M0 squamous cell carcinoma of pyriform sinus were subjected to total laryngectomy and pharyngoesophageal reconstruction of a circular (patient 1) and an anterior wall defect (patient 2) with radial forearm free flap and pectoralis major muscle flap, respectively. Both developed a pharyngocutaneous fistula and NPWT was used.A significant decrease of the fistula aperture and exudate was observed after 22 and 21 days of NPWT in patients 1 and 2, respectively. After that standard wound care was instituted and closure of the fistulae was accomplished in 5 and 7 days, respectively. Negative-pressure wound therapy can be an effective treatment for pharyngocutaneous fistula closure, either in the setting of fistulae that persist besides multiple surgical revisions using muscle flaps or as a first-line therapy when fistulae develops.

  19. Negative pressure wound therapy for treating leg ulcers.

    Science.gov (United States)

    Dumville, Jo C; Land, Lucy; Evans, Debra; Peinemann, Frank

    2015-07-14

    Leg ulcers are open skin wounds that occur between the ankle and the knee that can last weeks, months or even years and are a consequence of arterial or venous valvular insufficiency. Negative pressure wound therapy (NPWT) is a technology that is currently used widely in wound care and is promoted for use on wounds. NPWT involves the application of a wound dressing to the wound, to which a machine is attached. The machine applies a carefully controlled negative pressure (or vacuum), which sucks any wound and tissue fluid away from the treated area into a canister. To assess the effects of negative pressure wound therapy (NPWT) for treating leg ulcers in any care setting. For this review, in May 2015 we searched the following databases: the Cochrane Wounds Group Specialised Register (searched 21 May 2015); the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library 2015, Issue 4); Ovid MEDLINE (1946 to 20 May 2015); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 20 May 2015); Ovid EMBASE (1974 to 20 May 2015); EBSCO CINAHL (1982 to 21 May 2015). There were no restrictions based on language or date of publication. Published or unpublished randomized controlled trials (RCTs) comparing the effects of NPWT with alternative treatments or different types of NPWT in the treatment of leg ulcers. Two review authors independently performed study selection, risk of bias assessment and data extraction. We included one study, with 60 randomized participants, in the review. The study population had a range of ulcer types that were venous arteriolosclerotic and venous/arterial in origin. Study participants had recalcitrant ulcers that had not healed after treatment over a six-month period. Participants allocated to NPWT received continuous negative pressure until they achieved 100% granulation (wound preparation stage). A punch skin-graft transplantation was conducted and the wound then exposed to further NPWT for four days followed by standard care

  20. Physical fitness and cardiovascular response to lower body negative pressure

    Science.gov (United States)

    Raven, P. B.; Rohm-Young, D.; Blomqvist, C. G.

    1984-01-01

    Klein et al. (1977) have questioned the concept of endurance training as an appropriate means of preparing for prolonged space flights. Their opinion was mainly based on reports of endurance athletes who had a decreased tolerance to orthostatic or gravitational stress induced by lower body negative pressure (LBNP), upright tilt, or whole body water immersion. The present investigation had the objective to determine if the hemodynamic response to LBNP is different between a high and average fit group of subjects. In addition, the discrete aspect of cardiovascular function which had been altered by chronic training was to be identified. On the basis of the results of experiments conducted with 14 young male volunteers, it is concluded that the reflex response to central hypovolemia is altered by endurance exercise training.

  1. Homogeneous nucleation in liquid nitrogen at negative pressures

    Energy Technology Data Exchange (ETDEWEB)

    Baidakov, V. G., E-mail: baidakov@itp.uran.ru; Vinogradov, V. E.; Pavlov, P. A. [Russian Academy of Sciences, Institute of Thermal Physics, Ural Branch (Russian Federation)

    2016-10-15

    The kinetics of spontaneous cavitation in liquid nitrogen at positive and negative pressures has been studied in a tension wave formed by a compression pulse reflected from the liquid–vapor interface on a thin platinum wire heated by a current pulse. The limiting tensile stresses (Δp = p{sub s}–p, where p{sub s} is the saturation pressure), the corresponding bubble nucleation frequencies J (10{sup 20}–10{sup 22} s{sup –1} m{sup –3}), and temperature induced nucleation frequency growth rate G{sub T} = dlnJ/dT have been experimentally determined. At T = 90 K, the limiting tensile stress was Δp = 8.3 MPa, which was 4.9 MPa lower than the value corresponding to the boundary of thermodynamic stability of the liquid phase (spinodal). The measurement results were compared to classical (homogeneous) nucleation theory (CNT) with and without neglect of the dependence of the surface tension of critical bubbles on their dimensions. In the latter case, the properties of new phase nuclei were described in terms of the Van der Waals theory of capillarity. The experimental data agree well with the CNT theory when it takes into account the “size effect.”.

  2. Avaliação da pressão positiva expiratória final utilizando o aparelho fisioterápico Quake Evaluation of positive end expiratory pressure using a physiotherapy device called Quake

    Directory of Open Access Journals (Sweden)

    Cristiane Cenachi Coelho

    2009-12-01

    Full Text Available O objetivo deste estudo foi avaliar, em voluntários saudáveis, o valor médio da pressão positiva expiratória final (PEEP na utilização do recurso fisioterápico Quake, relativamente novo no mercado. Participaram 62 indivíduos de ambos os sexos, entre 18 e 30 anos, que foram submetidos a: prova de função pulmonar; avaliação do pico de fluxo expiratório, da sensação subjetiva de esforço (escala de Borg e da saturação de oxigênio; e à utilização do aparelho, acoplado a um manovacuômetro, para efetuar duas seqüências respiratórias, de 10 e 20 incursões por minuto, monitoradas por retroalimentação visual. Os dados foram tratados estatisticamente. Foi observada diferença significativa entre os valores das pressões geradas apenas na seqüência de 10 incursões por minuto (p=0,03. Na comparação das pressões entre as seqüências, os valores foram significativamente menores na de 10 incursões (29,42±8,04 cmH2O; p=0,03. Não foram encontradas correlações entre as pressões e as variáveis da espirometria, idade e pico de fluxo expiratório. Foi observada uma fraca correlação significativa antes (r=0,36; p=0,003 e depois (r=0,31; p=0,014 da seqüência de 20 incursões entre as pressões nessa seqüência e os escores de fadiga na escala de Borg, tendo o mesmo ocorido com a saturação de oxigênio. A PEEP gerada pelo Quake em indivíduos saudáveis varia de acordo com a frequência em incursões por minuto, sendo maior durante a seqüência mais rápida, que também gera maior cansaço.The aim of this study was to assess the mean positive end expiratory pressure (PEEP during use of the Quake, a relatively new device, in healthy volunteers. Participants were 62 subjects of both sexes aged 18 to 30 years old, who were submitted to: pulmonary function tests; expiratory peak flow evaluation; the Borg scale; assessment of oxygen saturation; and use of the device, coupled to a manometer, in two sequences, of 10 and 20

  3. Negative pressure wound therapy in patients with diabetic foot.

    Science.gov (United States)

    Ulusal, Ali Engin; Sahin, M Sükrü; Ulusal, Betül; Cakmak, Gökhan; Tuncay, Cengiz

    2011-01-01

    In this study our aim was to compare the results of standard dressing treatment to negative pressure wound therapy (NPWT) performed with a vacuum-assisted closure (VAC) device in patients with diabetic foot ulcers. We assessed the results of 35 patients treated for diabetic foot ulcer between 2006 and 2008. Of these cases, 20 (4 women and 16 men; mean age: 66 years; range: 52-90 years) were treated with standard wet dressings and 16 feet in 15 patients (10 men, 5 women; mean age: 58.9 years; range: 42-83 years) with VAC therapy. The success of treatment was evaluated in terms of hospitalization length and rate of limb salvation. The average hospitalization period with VAC treatment was 32 days compared to 59 days with standard dressing treatment. All patients treated with standard dressings eventually had to undergo amputation. However, the amputation rate was 37% in the VAC treated group and 88% of patients had a functional extremity at the end of treatment. VAC therapy, together with debridement and appropriate antibiotic therapy, enables a higher rate of limb salvage, especially in Wagner Grade 3 and Grade 4 ulcers.

  4. Negative pressure therapy for the treatment of complex wounds.

    Science.gov (United States)

    Lima, Renan Victor Kümpel Schmidt; Coltro, Pedro Soler; Farina, Jayme Adriano

    2017-01-01

    The objective of this study is to evaluate the effectiveness of negative pressure therapy (NPT) in the treatment of complex wounds, with emphasis on its mechanisms of action and main therapeutic indications. We searched the Pubmed / Medline database for articles published from 1997 to 2016, and selected the most relevant ones. The mechanisms of action of NPT involveboth physical effects, such as increased perfusion, control of edema and exudate, reduction of wound dimensions and bacterial clearance, and biological ones, such as the stimulation of granulation tissue formation, microdeformations and reduction of Inflammatory response. The main indications of NPT are complex wounds, such as pressure ulcers, traumatic wounds, operative wound dehiscences, burns, necrotizing wounds, venous ulcers, diabetic wounds, skin grafts, open abdomen, prevention of complications in closed incisions and in the association with instillation of solutions in infected wounds. RESUMO O objetivo desse estudo é avaliar a eficácia da terapia por pressão negativa (TPN) no tratamento de feridas complexas, com ênfase em seus mecanismos de ação e principais indicações terapêuticas. Foi realizada revisão na base de dados Pubmed / Medline, em artigos publicados de 1997 a 2016, e selecionados os mais relevantes. O mecanismo de ação da TPN envolve efeitos físicos, como o aumento da perfusão, controle do edema e do exsudato, redução das dimensões da ferida e depuração bacteriana, e biológicos, como o estímulo à formação de tecido de granulação, microdeformações e redução da resposta inflamatória local. As principais indicações da TPN são as feridas complexas como úlceras por pressão, feridas traumáticas, deiscências de ferida operatória, queimaduras, feridas necrotizantes, úlceras venosas, feridas diabéticas, os enxertos de pele, o abdome aberto, na prevenção de complicações em incisões fechadas e na associação com instilação de soluções em feridas

  5. A portable, disposable system for negative-pressure wound therapy.

    Science.gov (United States)

    Brandon, Tanya

    Negative-pressure wound therapy (NPWT) imparts a number of clinical effects that promote a healing response and, as such, is a well-established means of treating a variety of wound types. Historically, the technique has been primarily used in the hospital setting; however, the introduction of more portable devices has led to an increase in the use of NPWT in the homecare setting, thereby facilitating early discharge of patients from hospital and continuity of care in the community. Portable NPWT devices also have the potential to impact positively on patients' quality of life, allowing increased mobility and freedom to undertake normal activities of daily living. Following the development of its standard Avance® NPWT system and associated dressing kits, Mölnlycke Health Care (Gothenburg, Sweden) has introduced a single-patient-use, disposable NPWT system; Avance Solo. This has been developed with a view to maximising patient freedom and mobility, providing a single-patient-use NPWT solution for multi-week treatment to allow quick and easy discharge of patients from hospital to home, and reducing some of the challenges of logistics and administration associated with the provision of NPWT for the caregiver. As with the standard NPWT system, the single-patient use system is supplied with a number of products incorporating Safetac® adhesive technology to minimise the risk of patients suffering unnecessary pain and trauma associated with dressing changes. This article presents a series of case studies describing procedures and outcomes following the application of the Avance Solo single-patient-use system.

  6. Active Negative Pressure Peritoneal Therapy After Abbreviated Laparotomy

    Science.gov (United States)

    Roberts, Derek J.; Faris, Peter D.; Ball, Chad G.; Kubes, Paul; Tiruta, Corina; Xiao, Zhengwen; Holodinsky, Jessalyn K.; McBeth, Paul B.; Doig, Christopher J.; Jenne, Craig N.

    2015-01-01

    Objective: To determine whether active negative pressure peritoneal therapy with the ABThera temporary abdominal closure device reduces systemic inflammation after abbreviated laparotomy. Background: Excessive systemic inflammation after abdominal injury or intra-abdominal sepsis is associated with poor outcomes. Methods: We conducted a single-center, randomized controlled trial. Forty-five adults with abdominal injury (46.7%) or intra-abdominal sepsis (52.3%) were randomly allocated to the ABThera (n = 23) or Barker's vacuum pack (n = 22). On study days 1, 2, 3, 7, and 28, blood and peritoneal fluid were collected. The primary endpoint was the difference in the plasma concentration of interleukin-6 (IL-6) 24 and 48 hours after temporary abdominal closure application. Results: There was a significantly lower peritoneal fluid drainage from the ABThera at 48 hours after randomization. Despite this, there was no difference in plasma concentration of IL-6 at baseline versus 24 (P = 0.52) or 48 hours (P = 0.82) between the groups. There was also no significant intergroup difference in the plasma concentrations of IL-1β, −8, −10, or −12 p70 or tumor necrosis factor α between these time points. The cumulative incidence of primary fascial closure at 90 days was similar between groups (hazard ratio, 1.6; 95% confidence interval, 0.82–3.0; P = 0.17). However, 90-day mortality was improved in the ABThera group (hazard ratio, 0.32; 95% confidence interval, 0.11–0.93; P = 0.04). Conclusions: This trial observed a survival difference between patients randomized to the ABThera versus Barker's vacuum pack that did not seem to be mediated by an improvement in peritoneal fluid drainage, fascial closure rates, or markers of systemic inflammation. Trial Registration: ClinicalTrials.gov identifier NCT01355094. PMID:25536308

  7. Calibration methods for negative gauge pressure down to  ‑100 kPa

    Science.gov (United States)

    Bentouati, Djilali; Durgut, Yasin; Otal, Pierre; Plimmer, Mark; Pražák, Dominik; Sabuga, Wladimir; Ehlers, Sven; Sınır, Ekrem

    2018-03-01

    The measurement of negative gauge pressure is a field of increasing importance in science and industry. One of the main aims of the EMPIR Joint Research Project 14IND 06 pres2vac is to develop guidelines for it. We present a comparison of three different methods for measuring negative gauge pressure: (i) using two absolute pressure measuring instruments, (ii) generating a negative gauge pressure in the bell jar of the pressure balance, and (iii) using a ‘hanging piston’ pressure balance. The advantages and drawbacks are discussed and some preliminary results presented.

  8. Contrastive Analysis and Research on Negative Pressure Beam Tube System and Positive Pressure Beam Tube System for Mine Use

    Science.gov (United States)

    Wang, Xinyi; Shen, Jialong; Liu, Xinbo

    2018-01-01

    Against the technical defects of universally applicable beam tube monitoring system at present, such as air suction in the beam tube, line clogging, long sampling time, etc., the paper analyzes the current situation of the spontaneous combustion fire disaster forecast of mine in our country and these defects one by one. On this basis, the paper proposes a research thought that improving the positive pressure beam tube so as to substitute the negative pressure beam tube. Then, the paper introduces the beam tube monitoring system based on positive pressure technology through theoretical analysis and experiment. In the comparison with negative pressure beam tube, the paper concludes the advantage of the new system and draws the conclusion that the positive pressure beam tube is superior to the negative pressure beam tube system both in test result and test time. At last, the paper proposes prospect of the beam tube monitoring system based on positive pressure technology.

  9. Negative interstitial pressure in the peritendinous region during exercise

    DEFF Research Database (Denmark)

    Langberg, Henning; Skovgaard, D; Bülow, J

    1999-01-01

    In the present study, tissue pressure in the peritendinous area ventral to the human Achilles tendon was determined. The pressure was measured during rest and intermittent isometric calf muscle exercise at three torques (56, 112, and 168 Nm) 20, 40 and 50 mm proximal to the insertion of the tendon...... in 11 healthy, young individuals. In all experiments a linear significant decrease in pressure was obtained with increasing torque [e.g., at 40 mm: -0.4 +/- 0.3 mmHg (rest) to -135 +/- 12 mmHg (168 Nm)]. No significant differences were obtained among the three areas measured. On the basis...

  10. Peak expiratory flow rate and respiratory symptoms following ...

    African Journals Online (AJOL)

    Peak expiratory flow rate (PEFR) of 350 rural women aged (20-70 years) in Edo State, Nigeria who actively used wood as a source of fuel for cooking was measured. The height, chest circumference, weight and blood pressure of the women were also measured. Respiratory symptoms of cough with sputum production, ...

  11. Involvement of nitric oxide in the wound bed microcirculatory change during negative pressure wound therapy.

    Science.gov (United States)

    Sano, Hitomi; Ichioka, Shigeru

    2015-08-01

    This study investigated the role of nitric oxide (NO) in the mechanism of blood flow increase in the wound bed during negative pressure wound therapy (NPWT). We developed an improved experimental model that allowed visualisation of the wound bed microcirculation under NPWT. Wounds were created on the mouse ear, taking care to preserve the subdermal vascular plexus, because the wound bed microcirculation was visualised using an intravital microscope system. We investigated whether application of a NO synthase inhibitor (N(G) -nitro-l-arginine methyl ester: L-NAME) might diminish the effect of the NPWT in increasing the wound blood flow. The experimental animals were divided into a negative pressure group (negative pressure of -125 mmHg applied to the wound for 5 minutes; n = 8), and a negative pressure plus L-NAME group (administration of L-NAME prior to application of the negative pressure; n = 8). In the negative pressure group, significant increase of blood flow was observed at 1 minute after the negative pressure application, which was sustained until 5 minutes. On the contrary, in the negative pressure plus L-NAME group, no significant changes were observed throughout the period of observation. These findings suggest that NO synthesis is involved in the wound bed microcirculatory change induced by NPWT. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  12. Negative chemical pressure effects induced by Y substitution for Ca ...

    Indian Academy of Sciences (India)

    the magnetic chain may be useful to the overall understanding of the novel magnetism of the parent compound. Keywords. Spin-chains; Ca3Co2O6; chemical pressure; magnetic order; quantum tun- neling. PACS Nos 75.50.-y; 75.30.Cr; 75.40.Cx. 1. Introduction. Among spin-chain systems, the compound, Ca3Co2O6 [1,2], ...

  13. Infant ventilator design: performance during expiratory limb occlusion.

    Science.gov (United States)

    Hall, M W; Peevy, K J

    1983-01-01

    We examined the specifications and design of the inspiratory pressure regulating valve of 8 continuous flow, pressure-limited infant ventilators. Two pressure regulating designs are currently available; one placing the primary pressure regulating valve on the inspiratory limb, the other placing it on the expiratory limb. Seven ventilators incorporate the latter design to limit inspiratory pressure and must have a safety pressure-relief valve located on the inspiratory limb to vent pressure in case of circuit occlusion. These pressure-relief valves are generally set by the manufacturer far in excess of pressures normally used for infant ventilation. Alarm systems are often absent or inadequate to warn of high pressure conditions during circuit obstruction. A case report detailing the fatal complication of prolonged excessive airway pressure during circuit occlusion is presented. Improvements in the pressure-relief valve designs currently available are possible, and may be necessary to provide adequate protection from barotrauma. The majority of infant ventilators currently available expose the patient to unnecessary excessive airway pressures in the case of expiratory limb occlusion, and the lack of alarm systems may leave the operator unaware of malfunction.

  14. Dynamic Leg Exercise Improves Tolerance to Lower Body Negative Pressure

    Science.gov (United States)

    Watenpaugh, D. E.; Ballard, R. E.; Stout, M. S.; Murthy, G.; Whalen, R. T.; Hargens, A. R.

    1994-01-01

    These results clearly demonstrate that dynamic leg exercise against the footward force produced by LBNP substantially improves tolerance to LBNP, and that even cyclic ankle flexion without load bearing also increases tolerance. This exercise-induced increase of tolerance was actually an underestimate, because subjects who completed the tolerance test while exercising could have continued for longer periods. Exercise probably increases LBNP tolerance by multiple mechanisms. Tolerance was increased in part by skeletal muscle pumping venous blood from the legs. Rosenhamer and Linnarsson and Rosenhamer also deduced this for subjects cycling during centrifugation, although no measurements of leg volume were made in those studies: they found that male subjects cycling at 98 W could endure 3 Gz centrifugation longer than when they remained relaxed during centrifugation. Skeletal muscle pumping helps maintain cardiac filling pressure by opposing gravity-, centrifugation-, or LBNP-induced accumulation of blood and extravascular fluid in the legs.

  15. Mechanisms of lower body negative pressure-induced syncope

    Science.gov (United States)

    Davrath, Linda Ruble

    Although extensively investigated, the mechanisms of post-spaceflight orthostatic intolerance have not been elucidated. The working hypothesis was that a markedly reduced left ventricular end-systolic volume (LVESV) would be achieved during progressive, presyncopal-limited LBNP and would cause bradycardia and a fall in blood pressure, thus triggering syncope. Eight healthy men, age 25.1 ± 1.3 years, volunteered for the study. Subjects were exposed to graded levels of LBNP on two separate occasions. Changes in left ventricular end-diastolic volume and LVESV were measured, using two-dimensional echocardiography, at each stage of LBNP from rest to presyncope. Plasma venous blood samples were withdrawn at the end of each stage of the LBNP protocol for the measurement of plasma venous catecholamines and plasma renin activity (PRA). Catecholamines were analyzed by HPLC with electro-chemical detection, and PRA was determined by radioimmunoassay. All subjects reached presyncope during the LBNP. LVESV decreased by 28% at presyncope with no evidence of ventricular cavity obliteration. Norepinephrine (NE) increased by 44% from rest to presyncope, but no epinephrine surge was detected (35% increase from rest to presyncope). These data indicate that it is possible to initiate syncope with only a 28% decrease in LVESV, and that sympatho-inhibition and bradycardia are not required elements for syncope to occur. To investigate the effect of moderate sodium restriction on cardiovascular hemodynamics and orthostatic tolerance, presyncopal LBNP testing was performed. Urinary sodium excretion was significantly higher on the normal-sodium diet when compared with the sodium-restricted diet, but urinary potassium was not different. Cumulative stress index (655 ± 460 on normal-sodium diet vs. 639 ± 388 on sodium-restricted diet) scores were not different. Cardiac volumes, blood pressure and total peripheral resistance were not different at any stage of the LBNP between the diets, nor

  16. Negative-Pressure Hydrocephalus: A Case Report on Successful Treatment Under Intracranial Pressure Monitoring with Bilateral Ventriculoperitoneal Shunts.

    Science.gov (United States)

    Pandey, Sajan; Jin, Yi; Gao, Liang; Zhou, Cheng Cheng; Cui, Da Ming

    2017-03-01

    Negative-pressure hydrocephalus (NegPH), a very rare condition of unknown etiology and optimal treatment, usually presents postneurosurgery with clinical and imaging features of hydrocephalus, but with negative cerebrospinal fluid pressure. We describe a NegPH case of -3 mm Hg intracranial pressure that was successfully treated to achieve 5 mm Hg under continuous intracranial pressure monitoring with horizontal positioning, head down and legs elevated to 10°-15°, neck wrapping for controlled venous drainage, chest and abdomen bandages, infusion of 5% dextrose fluid to lower plasma osmolarity (Na + , 130-135 mmol/L), daily cerebrospinal fluid drainage >200 mL, and arterial blood gas partial pressure of carbon dioxide >40 mm Hg. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Negative-pressure therapy versus standard wound care: a meta-analysis of randomized trials.

    Science.gov (United States)

    Suissa, Daniel; Danino, Alain; Nikolis, Andreas

    2011-11-01

    Several randomized controlled trials comparing negative-pressure therapy to standard wound care for chronic wounds have been published. Although these studies suggest a benefit for negative-pressure therapy, the majority of the review articles on the topic conclude that the studies are inconclusive. The authors conducted a quantitative meta-analysis of the effectiveness of negative-pressure therapy for the management of chronic wounds. The MEDLINE, EMBASE, and Cochrane databases were searched from 1993 to March of 2010 for randomized controlled trials comparing negative-pressure therapy to standard wound care for chronic wounds. Measures of wound size and time to healing, along with the corresponding p values, were extracted from the randomized controlled trials. Relative change ratios of wound size and ratios of median time to healing were combined using a random effects model for meta-analysis. Ten trials of negative-pressure therapy versus standard wound care were found. In the negative-pressure therapy group, wound size had decreased significantly more than in the standard wound care group (relative change ratio, 0.77; 95 percent confidence interval, 0.63 to 0.96). Time to healing was significantly shorter in the negative-pressure therapy group in comparison with the standard wound care group (ratio of median time to healing, 0.74; 95 percent confidence interval, 0.70 to 0.78). This quantitative meta-analysis of randomized trials suggests that negative-pressure therapy appears to be an effective treatment for chronic wounds. An effect of publication bias cannot be ruled out. Therapeutic, II.

  18. Management of High-Voltage Burns of the Hand and Wrist with Negative Pressure Dressing

    Directory of Open Access Journals (Sweden)

    Nazım Gümüş

    2017-12-01

    Full Text Available Objective: Negative pressure dressing stimulates wound healing by promoting cellular proliferation and regeneration. It also removes interstitial edema and increases local blood flow, resulting in rapid growth of the granulation tissue. We used the dressing method in deep hand and wrist burns caused by high-voltage electrical current, which leads to progressive tissue necrosis, elevated compartment pressure, and deep tissue edema, to reveal if subatmospheric pressure could limit the zone of injury or ongoing tissue necrosis after electrical burn. Material and Methods: Six hands of five patients, who came in contact with high-voltage electrical wire carrying more than 1000 volts, are presented in this study. Hands and wrists were seriously injured and contracted. After the initial treatment involving fluid resuscitation, fasciotomy, carpal tunnel release, and debridement, a negative pressure dressing was applied to the wounds of hand, wrist, and forearm with 125 mm Hg continuous pressure, and maintained for 20 days. Results: When negative pressure dressing was stopped on the 20th day, significant granulation tissue developed over the hand and forearm wounds. However, wrist wounds needed more debridement and repeated dressings because of the presence of necrosis. Edema of the hands subsided significantly during the use of negative pressure dressing. Time to closure for hand and forearm wounds decreased considerably. Moreover, in one wrist, spontaneous closure was achieved at about one month. All hands except one treated with negative pressure dressing could be saved from amputation; however, significant tissue loss developed, needing complex reconstruction procedures. One hand was amputated because of the permanent loss of blood perfusion. Conclusion: The management of high-voltage burns of hand and wrist with subatmospheric pressure appears to be capable of reducing hand edema and accelerating closure of the wounds. It seems that negative

  19. An expiratory assist during spontaneous breathing can compensate for endotracheal tube resistance.

    Science.gov (United States)

    Uchiyama, Akinori; Chang, Cheng; Suzuki, Shinya; Mashimo, Takashi; Fujino, Yuji

    2009-08-01

    Although inspiratory assist of spontaneous breathing in intubated patients is common, expiratory assist functions have rarely been reported. Effective expiratory support (ES) could be used to compensate for endotracheal tube (ETT) resistance during spontaneous breathing. In this study, we examined the performance of a new system designed to provide both inspiratory support (IS) and ES during spontaneous breathing with the goal of reducing the effective resistance of the ETT. The ES system consisted of a ventilator demand valve and a computer-controlled piston cylinder, which aspirated gas from the respiratory circuit during the expiratory phase. The movement of the piston was synchronized with spontaneous breathing. We compared the pressures at the tip of the ETT and in the breathing circuit during spontaneous breathing through an ETT of internal diameter (ID) 5 mm with that of an ETT with ID 8 mm in nine healthy adult male volunteers. The ventilatory mode was set to maintain a continuous airway pressure of 0 cm H(2)O. Three ventilator settings (no support, IS only, and IS plus ES) were compared using ID 5 mm ETT. We monitored pressure in the breathing circuit (P(aw)), ETT tip pressure (P(tip)), and respiratory flow. The P(tip) of the ID 5 mm ETT showed a large negative deflection during inspiration and a positive deflection during expiration without support. IS alone did not improve the respiratory pattern through the small ETT. However, IS plus ES resulted in negative P(aw) during expiration in addition to positive deflection of P(aw) during inspiration, making the pressure characteristics of P(tip) similar to those of ID 8 mm ETT. Moreover, IS plus ES produced a respiratory pattern through the ID 5 mm ETT that was similar to that through the ID 8 mm ETT. In this study of healthy volunteers, IS plus ES compensated for the airway resistance imposed by a ID 5.0 mm ETT to create pressure changes at the tip of the ETT similar to those of an ID 8.0 mm ETT.

  20. Diagnostic methods to assess inspiratory and expiratory muscle strength

    Directory of Open Access Journals (Sweden)

    Pedro Caruso

    2015-04-01

    Full Text Available Impairment of (inspiratory and expiratory respiratory muscles is a common clinical finding, not only in patients with neuromuscular disease but also in patients with primary disease of the lung parenchyma or airways. Although such impairment is common, its recognition is usually delayed because its signs and symptoms are nonspecific and late. This delayed recognition, or even the lack thereof, occurs because the diagnostic tests used in the assessment of respiratory muscle strength are not widely known and available. There are various methods of assessing respiratory muscle strength during the inspiratory and expiratory phases. These methods are divided into two categories: volitional tests (which require patient understanding and cooperation; and non-volitional tests. Volitional tests, such as those that measure maximal inspiratory and expiratory pressures, are the most commonly used because they are readily available. Non-volitional tests depend on magnetic stimulation of the phrenic nerve accompanied by the measurement of inspiratory mouth pressure, inspiratory esophageal pressure, or inspiratory transdiaphragmatic pressure. Another method that has come to be widely used is ultrasound imaging of the diaphragm. We believe that pulmonologists involved in the care of patients with respiratory diseases should be familiar with the tests used in order to assess respiratory muscle function.Therefore, the aim of the present article is to describe the advantages, disadvantages, procedures, and clinical applicability of the main tests used in the assessment of respiratory muscle strength.

  1. Experimental study of a negative corona in atmospheric-pressure argon

    International Nuclear Information System (INIS)

    Dandaron, G.-N. B.; Baldanov, B. B.

    2007-01-01

    Results are presented from experimental studies of a negative point-to-plane dc corona in atmospheric-pressure argon. Several operating modes are identified: a hysteresis region, a repetitive mode, and a glow-discharge mode. The effect of gas-dynamic parameters on the characteristics of a repetitive negative corona is investigated

  2. Atrial distension, arterial pulsation, and vasopressin release during negative pressure breathing in humans

    DEFF Research Database (Denmark)

    Pump, B; Damgaard, M; Gabrielsen, A

    2001-01-01

    During an antiorthostatic posture change, left atrial (LA) diameter and arterial pulse pressure (PP) increase, and plasma arginine vasopressin (AVP) is suppressed. By comparing the effects of a 15-min posture change from seated to supine with those of 15-min seated negative pressure breathing...... in eight healthy males, we tested the hypothesis that with similar increases in LA diameter, suppression of AVP release is dependent on the degree of increase in PP. LA diameter increased similarly during the posture change and negative pressure breathing (-9 to -24 mmHg) from between 30 and 31 +/- 1 to 34...... +/- 1 mm (P breathing from 36 +/- 3 to 42 +/- 3 mmHg (P

  3. Application of vacuum-assisted closure in seawater-immersed wound treatment under different negative pressures.

    Science.gov (United States)

    Cao, L; Peng, M M; Sun, J J; Yu, X C; Shi, B

    2015-06-11

    The therapeutic effect of vacuum-assisted closure (VAC) has been confirmed in many types of complex wounds, but there are few relevant reports regarding seawater-immersed wounds. The aim of this study was to determine the effect of VAC on seawater-immersed wound healing under different negative pressures and explore the optimal negative pressure value. Four purebred miniature pigs were used as the experimental animal models. Four acute, symmetrical wounds were made on each side of the spine and designated as the experimental group (wounds with 2 h of seawater immersion) and the control group (wounds without seawater immersion). Wounds were divided into a conventional dressing group and 3 further groups with different VAC therapies (negative pressure at either 120, 180, or 240 mmHg). The extent of wound healing, and speed of granulation growth and re-epithelialization were measured. Bacterial flora distribution in the wounds was observed, and fibronectin levels in the exudate of the wounds were tested. Results showed that seawater immersion aggravated wound injury and that VAC therapy with 180 mmHg negative pressure induced the fastest epidermis migration, obvious edema elimination, significant capillary proliferation, and the highest level of fibronectin, and that in wounds, the proportion of Gram-negative bacteria tended to decrease and that of Gram-positive bacteria tended to increase. Our results show that VAC promotes seawater-immersed wound healing and that 180 mmHg negative pressure may be optimal for wound healing.

  4. Measurement of negative ion mobilities in O2 and O3 mixtures at atmospheric pressure

    International Nuclear Information System (INIS)

    Itoh, H.; Norimoto, K.; Hayashi, T.

    1998-01-01

    Mobility measurements of negative molecular oxygen ions in pure oxygen and in an oxygen-ozone mixture are reported. A cascaded gap consisting of an ion drift gap and an ion detection gap was used in the experiment. The ion detection gap was formed by a positive point and a grounded plane electrode was operated at atmospheric pressure. The zero field mobility of negative molecular oxygen ions was determined to be 2.07+-0.02 cm 2 /V.s. A somewhat higher value of oxygen mobility was found at higher electric field/pressure ratios; this is presumed to be due to negative ozone ions. When changing the electric field/pressure ratio the mobility of negative oxygen ions in oxygen-ozone mixtures becomes smaller than that in pure oxygen; this is probably due to the cumulative effect of other particles produced by silent discharges. (J.U.)

  5. Improved wound management by regulated negative pressure-assisted wound therapy and regulated, oxygen- enriched negative pressure-assisted wound therapy through basic science research and clinical assessment

    OpenAIRE

    Moris Topaz

    2012-01-01

    Regulated negative pressure-assisted wound therapy (RNPT) should be regarded as a state-of-the-art technology in wound treatment and the most important physical, nonpharmaceutical, platform technology developed and applied for wound healing in the last two decades. RNPT systems maintain the treated wound's environment as a semi-closed, semi-isolated system applying external physical stimulations to the wound, leading to biological and biochemical effects, with the potential to substantially i...

  6. Proposal Intensity Adequacy of Expiratory Effort and Heart Rate Behavior During the Valsalva Maneuver in Preadolescents

    Directory of Open Access Journals (Sweden)

    Mario Augusto Paschoal

    2014-08-01

    Full Text Available Background: When performing the Valsalva maneuver (VM, adults and preadolescents produce the same expiratory resistance values. Objective: To analyze heart rate (HR in preadolescents performing VM, and propose a new method for selecting expiratory resistance. Method: The maximal expiratory pressure (MEP was measured in 45 sedentary children aged 9-12 years who subsequently performed VM for 20 s using an expiratory pressure of 60%, 70%, or 80% of MEP. HR was measured before, during, and after VM. These procedures were repeated 30 days later, and the data collected in the sessions (E1, E2 were analyzed and compared in periods before, during (0-10 and 10-20 s, and after VM using nonparametric tests. Results: All 45 participants adequately performed VM in E1 and E2 at 60% of MEP. However, only 38 (84.4% and 25 (55.5% of the participants performed the maneuver at 70% and 80% of MEP, respectively. The HR delta measured during 0-10 s and 10-20 s significantly increased as the expiratory effort increased, indicating an effective cardiac autonomic response during VM. However, our findings suggest the VM should not be performed at these intensities. Conclusion: HR increased with all effort intensities tested during VM. However, 60% of MEP was the only level of expiratory resistance that all participants could use to perform VM. Therefore, 60% of MEP may be the optimal expiratory resistance that should be used in clinical practice.

  7. Asymmetric Fuzzy Control of a Positive and Negative Pneumatic Pressure Servo System

    Science.gov (United States)

    Yang, Gang; Du, Jing-Min; Fu, Xiao-Yun; Li, Bao-Ren

    2017-11-01

    The pneumatic pressure control systems have been used in some fields. However, the researches on pneumatic pressure control mainly focus on constant pressure regulation. Poor dynamic characteristics and strong nonlinearity of such systems limit its application in the field of pressure tracking control. In order to meet the demand of generating dynamic pressure signal in the application of the hardware-in-the-loop simulation of aerospace engineering, a positive and negative pneumatic pressure servo system is provided to implement dynamic adjustment of sealed chamber pressure. A mathematical model is established with simulation and experiment being implemented afterwards to discuss the characteristics of the system, which shows serious asymmetry in the process of charging and discharging. Based on the analysis of the system dynamics, a fuzzy proportional integral derivative (PID) controller with asymmetric fuzzy compensator is proposed. Different from conventional adjusting mechanisms employing the error and change in error of the controlled variable as input parameters, the current chamber pressure and charging or discharging state are chosen as inputs of the compensator, which improves adaptability. To verify the effectiveness and performance of the proposed controller, the comparison experiments tracking sinusoidal and square wave commands are conducted. Experimental results show that the proposed controller can obtain better dynamic performance and relatively consistent control performance across the scope of work (2-140 kPa). The research proposes a fuzzy control method to overcome asymmetry and enhance adaptability for the positive and negative pneumatic pressure servo system.

  8. Study of continuous irrigation negative-pressure treatment using an original ulceration model.

    Science.gov (United States)

    Sano, Hitomi; Kajikawa, Akiyoshi; Ueda, Kazuki

    2013-06-01

    A continuous irrigation with intermittent aspiration (CIIA) method has previously been developed in the treatment of infected expander sites. For the purpose of treatment of infected wounds, a new intermittent negative pressure irrigation treatment (INPIT) has been developed that is a combination of CIIA with topical negative-pressure therapy. This study aims to investigate the efficacy of INPIT. The efficacy of irrigation was investigated by changing the conditions including the location and the number of irrigation tubes, flow volume, and the timetable of negative-pressure application using original ulcer models. Although the presence of side holes and increase in the number of tubes or flow volume improved the irrigation efficacy, non-washed-out areas remained. On the other hand, INPIT allowed more uniform and wide area washing even at low flow volume. The results suggest that INPIT is superior to general conventional continuous irrigation treatment in irrigation efficiency.

  9. [Closure of cystic cavity-type bedsore by subcutaneous undermining dissection with continuous negative pressure drainage].

    Science.gov (United States)

    Li, Jiang; Guo, Xiao-Ping; Wang, Ke-Hua; Zhao, Dong-Hong; Han, Tong; Lang, Yu-Hong; Peng, Li-Jun

    2012-03-01

    To investigate the clinical effect of subcutaneous undermining dissection with continuous negative pressure drainage for the closure of cystic cavity-type bedsore. 12 patients with cystic cavity-type bedsore underwent surgical debridement and the wounds were closed after subcutaneous undermining dissection. The negative pressure drainage was put in the deep space. The healing process was observed. Completed healing was achieved in all the 12 cases. The skin wounds healed after 17-20 days and the deep spaces closed after 36-43 days. 12 cases were followed up for 1 year with no occurrence. It is an easy and effective method to treat cystic cavity -type bedsore by subcutaneous undermining dissection with continuous negative pressure drainage.

  10. Negative Pressure Pulmonary Edema Following use of Laryngeal Mask Airway (LMA

    Directory of Open Access Journals (Sweden)

    Yesim Bayraktar

    2013-06-01

    Full Text Available Negative pressure pulmonary edema (NPPE following upper airway obstruction is a non-cardiogenic pulmonary edema. The first cause in the etiology of NPPE is developed laryngospasm after intubation or extubation, while the other causes are epiglotitis, croup, hiccups, foreign body aspiration, pharyngeal hematoma and oropharyngeal tumors.The Late diagnosis and treatment causes high morbidity and mortality. The protection of the airway and maintainance of arterial oxygenation will be life saving.In this article we aimed to report  a case of negative pressure pulmonary edema, resolved succesfully after treatment, following use of laryngeal mask airway (LMA.

  11. Perceiving social pressure not to feel negative predicts depressive symptoms in daily life.

    Science.gov (United States)

    Dejonckheere, Egon; Bastian, Brock; Fried, Eiko I; Murphy, Sean C; Kuppens, Peter

    2017-09-01

    Western societies often overemphasize the pursuit of happiness, and regard negative feelings such as sadness or anxiety as maladaptive and unwanted. Despite this emphasis on happiness, the amount of people suffering from depressive complaints is remarkably high. To explain this apparent paradox, we examined whether experiencing social pressure not to feel sad or anxious could in fact contribute to depressive symptoms. A sample of individuals (n = 112) with elevated depression scores (Patient Health Questionnaire [PHQ-9] ≥ 10) took part in an online daily diary study in which they rated their depressive symptoms and perceived social pressure not to feel depressed or anxious for 30 consecutive days. Using multilevel VAR models, we investigated the temporal relation between this perceived social pressure and depressive symptoms to determine directionality. Primary analyses consistently indicated that experiencing social pressure predicts increases in both overall severity scores and most individual symptoms of depression, but not vice versa. A set of secondary analyses, in which we adopted a network perspective on depression, confirmed these findings. Using this approach, centrality analysis revealed that perceived social pressure not to feel negative plays an instigating role in depression, reflected by the high out- and low instrength centrality of this pressure in the various depression networks. Together, these findings indicate how perceived societal norms may contribute to depression, hinting at a possible malignant consequence of society's denouncement of negative emotions. Clinical implications are discussed. © 2017 Wiley Periodicals, Inc.

  12. Non-linear Heart Rate and Blood Pressure Interaction in Response to Lower-Body Negative Pressure

    Directory of Open Access Journals (Sweden)

    Ajay K. Verma

    2017-10-01

    Full Text Available Early detection of hemorrhage remains an open problem. In this regard, blood pressure has been an ineffective measure of blood loss due to numerous compensatory mechanisms sustaining arterial blood pressure homeostasis. Here, we investigate the feasibility of causality detection in the heart rate and blood pressure interaction, a closed-loop control system, for early detection of hemorrhage. The hemorrhage was simulated via graded lower-body negative pressure (LBNP from 0 to −40 mmHg. The research hypothesis was that a significant elevation of causal control in the direction of blood pressure to heart rate (i.e., baroreflex response is an early indicator of central hypovolemia. Five minutes of continuous blood pressure and electrocardiogram (ECG signals were acquired simultaneously from young, healthy participants (27 ± 1 years, N = 27 during each LBNP stage, from which heart rate (represented by RR interval, systolic blood pressure (SBP, diastolic blood pressure (DBP, and mean arterial pressure (MAP were derived. The heart rate and blood pressure causal interaction (RR↔SBP and RR↔MAP was studied during the last 3 min of each LBNP stage. At supine rest, the non-baroreflex arm (RR→SBP and RR→MAP showed a significantly (p < 0.001 higher causal drive toward blood pressure regulation compared to the baroreflex arm (SBP→RR and MAP→RR. In response to moderate category hemorrhage (−30 mmHg LBNP, no change was observed in the traditional marker of blood loss i.e., pulse pressure (p = 0.10 along with the RR→SBP (p = 0.76, RR→MAP (p = 0.60, and SBP→RR (p = 0.07 causality compared to the resting stage. Contrarily, a significant elevation in the MAP→RR (p = 0.004 causality was observed. In accordance with our hypothesis, the outcomes of the research underscored the potential of compensatory baroreflex arm (MAP→RR of the heart rate and blood pressure interaction toward differentiating a simulated moderate category hemorrhage from

  13. Negative magnetoresistance of pitch-based carbon fibers Temperature and pressure dependence

    Science.gov (United States)

    Hambourger, P. D.

    1986-01-01

    The negative transverse magnetoresistance of high-modulus pitch-based carbon fibers has been measured over the temperature range 1.3-4.2 K at ambient pressure and at 4.2 K under hydrostatic pressure up to 16 kbar. At low fields (less than 0.5 torr) the magnitude of the magnetoresistance increases markedly as the temperature is lowered from 4.2 K to 1.3 K, in disagreement with Bright's theoretical model, and decreases with pressure at the rate -0.6 percent/kbar.

  14. Topical negative pressure effects on coronary blood flow in a sternal wound model

    DEFF Research Database (Denmark)

    Lindstedt, Sandra; Malmsjö, Malin; Gesslein, Bodil

    2008-01-01

    patients with topical negative pressure (TNP)-treated mediastinitis and CABG patients without mediastinitis. The present study was designed to elucidate if TNP, applied over the myocardium, resulted in an increase of the total amount of coronary blood flow. Six pigs underwent median sternotomy...

  15. Closed incision prophylactic negative pressure wound therapy in patients undergoing major complex abdominal wall repair

    NARCIS (Netherlands)

    de Vries, F. E. E.; Atema, J. J.; Lapid, O.; Obdeijn, M. C.; Boermeester, M. A.

    2017-01-01

    Purpose To evaluate if incisional prophylactic negative pressure wound therapy (pNPWT) reduces wound infections and other wound complications in high-risk patients undergoing major complex ventral abdominal wall repair. Methods Retrospective before-after comparison nested in a consecutive series of

  16. The Application of Negative Pressure Wound Therapy with Installation in Diabetic Foot Associated with Phlegmon.

    Science.gov (United States)

    Wachal, Krzysztof; Szmyt, Krzysztof; Wachal, Magda; Stanisic, Michał

    2015-03-01

    The negative pressure wound therapy in the treatment of diabetic foot ulcers was used successfully for many years. In the case of complications associated with infection by this type of wound treatment to give very good results. From many years of sustained research on a device that could combine the advantages of the negative pressure wound therapy and drainage flow. Finally, in the last year, the first V.A.C. Ulta (KCI, USA) devices were included to the Polish hospital departments. In this paper we present a case of a patient of successfully using a negative pressure wound therapy with installation via a set of V.A.C. Ulta in the ischemic diabetic foot syndrome complicated by phlegmon and tissue necrosis. The patient was treated in stages. In first stage was performed angioplasty of critically stenosis of the superficial femoral artery segment. Secondly, the resection of the necrotic bone revised fingers and forefoot was conducted, and in the third step the negative pressure wound therapy with installation was used. Finally, the wound was closed by the intermediate thickness skin graft. The total duration of treatment was 21 days. The patient in good general condition with a completely healed wound was discharged. Currently, after the supply with orthopedic equipment, patient regained full mobility.

  17. Outcome of Negative-Pressure Wound Therapy for Open Abdomen Treatment After Nontraumatic Lower Gastrointestinal Surgery

    DEFF Research Database (Denmark)

    Bertelsen, Claus Anders; Fabricius, Rasmus; Kleif, Jakob

    2014-01-01

    Few studies have focused on the risk factors for failure to achieve fascial closure after use of negative-pressure wound therapy (NPWT) in an open abdomen (OA). We aimed at analyzing possible risk factors for failure of fascial closure and the risk of fistulas after nontrauma lower gastrointestinal...

  18. A cardiovascular system model for lower-body negative pressure response

    Science.gov (United States)

    Mitchell, B. A., Jr.; Giese, R. P.

    1971-01-01

    Mathematical models used to study complex physiological control systems are discussed. Efforts were made to modify a model of the cardiovascular system for use in studying lower body negative pressure. A computer program was written which allows orderly, straightforward expansion to include exercise, metabolism (thermal stress), respiration, and other body functions.

  19. Using the Solving Problems Together Psychoeducational Group Counseling Model as an Intervention for Negative Peer Pressure

    Science.gov (United States)

    Hall, Kimberly R.; Rushing, Jeri Lynn; Khurshid, Ayesha

    2011-01-01

    Problem-focused interventions are considered to be one of the most effective group counseling strategies with adolescents. This article describes a problem-focused group counseling model, Solving Problems Together (SPT), that focuses on working with students who struggle with negative peer pressure. Adapted from the teaching philosophy of…

  20. A systematic review of topical negative pressure therapy for acute and chronic wounds

    NARCIS (Netherlands)

    Ubbink, D. T.; Westerbos, S. J.; Nelson, E. A.; Vermeulen, H.

    2008-01-01

    Topical negative pressure (TNP) therapy is becoming increasingly popular for all kinds of wounds. Its clinical and cost effectiveness is unclear. A search of randomized controlled trials (RCTs) on TNP in adult patients with all kinds of wounds in all settings was undertaken in Medline, Embase,

  1. NEGATIVE PRESSURE WOUND THERAPY (NPWT FOR THE MANAGEMENT OF DIABETIC FOOT WOUND

    Directory of Open Access Journals (Sweden)

    Wesiana Heris Santy

    2015-11-01

    Full Text Available Complications often experienced by people with diabetes are complications in the feet ( 15 % called diabetic foot ( Akhtyo , 2009 . Where the injury to the leg if not treated properly will lead to infections and ultimately need to be amputated .The purpose of writing articles is to review and discuss the evidence-based literature bersadarkanpraktice of Negative Pressure Wound Therapy Effectiveness ( NPWT on the healing of diabetic foot ulcers.One technology that is used to prevent and avoid lower limb amputation is the technique of negative pressure or Negative Pressure Wound Therapy ( NPWT . This negative pressure technique has grown rapidly and now has been widely used in many countries , especially in Western European countries ( Germany and the United States . Negative pressure technique has the advantage that it is relatively cheaper cost than the use of hyperbaric oxygen . Results obtained by several studies that the use of NPWT may improve wound healing process through efforts to create a moist wound environment and decrease edema that becomes optimal wound healing , throw that out of the wound exudate so that the protease enzyme in the exudate also go wasted , this enzyme is known to interfere wound healing process . The other benefit is that it can stimulate cell growth by increasing angiogenesis physically , so that the growth of new cells will be maximal Abstrak : Komplikasi sering dialami pengidap diabetes adalah komplikasi pada kaki (15% disebut kaki diabetes (Akhtyo, 2009.Dimana luka pada kaki jika tidak ditangani dengan baik akan menyebabkan terjadinya infeksi dan akhirnya perlu di amputasi. Tujuan penulisan artikel adalah mengkaji dan membahas literature bersadarkan evidence based praktice  tentang Efektifitas Negative Pressure Wound Therapy (NPWT pada penyembuhan ulkus kaki Diabetik. Salah satu teknologi yang digunakan untuk mencegah dan menghindari amputasi ekstremitas bawah adalah  teknik tekanan negatif atau Negative

  2. Improved wound management by regulated negative pressure-assisted wound therapy and regulated, oxygen- enriched negative pressure-assisted wound therapy through basic science research and clinical assessment

    Directory of Open Access Journals (Sweden)

    Moris Topaz

    2012-01-01

    Full Text Available Regulated negative pressure-assisted wound therapy (RNPT should be regarded as a state-of-the-art technology in wound treatment and the most important physical, nonpharmaceutical, platform technology developed and applied for wound healing in the last two decades. RNPT systems maintain the treated wound′s environment as a semi-closed, semi-isolated system applying external physical stimulations to the wound, leading to biological and biochemical effects, with the potential to substantially influence wound-host interactions, and when properly applied may enhance wound healing. RNPT is a simple, safe, and affordable tool that can be utilized in a wide range of acute and chronic conditions, with reduced need for complicated surgical procedures, and antibiotic treatment. This technology has been shown to be effective and safe, saving limbs and lives on a global scale. Regulated, oxygen-enriched negative pressure-assisted wound therapy (RO-NPT is an innovative technology, whereby supplemental oxygen is concurrently administered with RNPT for their synergistic effect on treatment and prophylaxis of anaerobic wound infection and promotion of wound healing. Understanding the basic science, modes of operation and the associated risks of these technologies through their fundamental clinical mechanisms is the main objective of this review.

  3. Improved wound management by regulated negative pressure-assisted wound therapy and regulated, oxygen- enriched negative pressure-assisted wound therapy through basic science research and clinical assessment.

    Science.gov (United States)

    Topaz, Moris

    2012-05-01

    Regulated negative pressure-assisted wound therapy (RNPT) should be regarded as a state-of-the-art technology in wound treatment and the most important physical, nonpharmaceutical, platform technology developed and applied for wound healing in the last two decades. RNPT systems maintain the treated wound's environment as a semi-closed, semi-isolated system applying external physical stimulations to the wound, leading to biological and biochemical effects, with the potential to substantially influence wound-host interactions, and when properly applied may enhance wound healing. RNPT is a simple, safe, and affordable tool that can be utilized in a wide range of acute and chronic conditions, with reduced need for complicated surgical procedures, and antibiotic treatment. This technology has been shown to be effective and safe, saving limbs and lives on a global scale. Regulated, oxygen-enriched negative pressure-assisted wound therapy (RO-NPT) is an innovative technology, whereby supplemental oxygen is concurrently administered with RNPT for their synergistic effect on treatment and prophylaxis of anaerobic wound infection and promotion of wound healing. Understanding the basic science, modes of operation and the associated risks of these technologies through their fundamental clinical mechanisms is the main objective of this review.

  4. The use of continuous negative pressure after open debridement for septic arthritis of the shoulder.

    Science.gov (United States)

    Jung, H J; Song, J H; Kekatpure, A L; Adikrishna, A; Hong, H P; Lee, W J; Chun, J M; Jeon, I H

    2016-05-01

    The treatment of septic arthritis of the shoulder is challenging. The infection frequently recurs and the clinical outcome can be very poor. We aimed to review the outcomes following the use of continuous negative pressure after open debridement with a large diameter drain in patients with septic arthritis of the shoulder. A total of 68 consecutive patients with septic arthritis of the shoulder underwent arthrotomy, irrigation and debridement. A small diameter suction drain was placed in the glenohumeral joint and a large diameter drain was placed in the subacromial space with continuous negative pressure of 15 cm H2O. All patients received a standardised protocol of antibiotics for a mean of 5.1 weeks (two to 11.1). Negative pressure was maintained for a mean of 24 days (14 to 32). A total of 67 patients (98.5%) were cured without further treatment being required. At a mean follow-up of 14 months (three to 72), the mean forward flexion was 123° (80° to 140°) and the mean external rotation was 28°(10° to 40°) in those with a rotator cuff tear, and 125° (85° to 145°) and 35° (15° to 45°) in those without a rotator cuff tear. Continuous negative pressure, following open arthrotomy, irrigation and debridement, was effective in treating septic arthritis of the shoulder. The rate of recurrence was significantly lower than with conventional treatment involving arthroscopic or open debridement reported in the literature. Functional outcomes, even in patients with rotator cuff tears, were excellent. Continuous negative pressure is effective in treating septic arthritis of the shoulder. Cite this article: Bone Joint J 2016;98-B:660-5. ©2016 The British Editorial Society of Bone & Joint Surgery.

  5. Novel cavitation fluid jet polishing process based on negative pressure effects.

    Science.gov (United States)

    Chen, Fengjun; Wang, Hui; Tang, Yu; Yin, Shaohui; Huang, Shuai; Zhang, Guanghua

    2018-04-01

    Traditional abrasive fluid jet polishing (FJP) is limited by its high-pressure equipment, unstable material removal rate, and applicability to ultra-smooth surfaces because of the evident air turbulence, fluid expansion, and a large polishing spot in high-pressure FJP. This paper presents a novel cavitation fluid jet polishing (CFJP) method and process based on FJP technology. It can implement high-efficiency polishing on small-scale surfaces in a low-pressure environment. CFJP uses the purposely designed polishing equipment with a sealed chamber, which can generate a cavitation effect in negative pressure environment. Moreover, the collapse of cavitation bubbles can spray out a high-energy microjet and shock wave to enhance the material removal. Its feasibility is verified through researching the flow behavior and the cavitation results of the negative pressure cavitation machining of pure water in reversing suction flow. The mechanism is analyzed through a computational fluid dynamics simulation. Thus, its cavitation and surface removal mechanisms in the vertical CFJP and inclined CFJP are studied. A series of polishing experiments on different materials and polishing parameters are conducted to validate its polishing performance compared with FJP. The maximum removal depth increases, and surface roughness gradually decreases with increasing negative outlet pressures. The surface becomes smooth with the increase of polishing time. The experimental results confirm that the CFJP process can realize a high material removal rate and smooth surface with low energy consumption in the low-pressure environment, together with compatible surface roughness to FJP. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. A rigid disc for protection of exposed blood vessels during negative pressure wound therapy.

    Science.gov (United States)

    Anesäter, Erik; Borgquist, Ola; Torbrand, Christian; Roupé, K Markus; Ingemansson, Richard; Lindstedt, Sandra; Malmsjö, Malin

    2013-02-01

    There are increasing reports of serious complications and deaths associated with negative pressure wound therapy (NPWT). Bleeding may occur when NPWT is applied to a wound with exposed blood vessels. Inserting a rigid disc in the wound may protect these structures. The authors examined the effects of rigid discs on wound bed tissue pressure and blood flow through a large blood vessel in the wound bed during NPWT. Wounds were created over the femoral artery in the groin of 8 pigs. Rigid discs were inserted. Wound bed pressures and arterial blood flow were measured during NPWT. Pressure transduction to the wound bed was similar for control wounds and wounds with discs. Blood flow through the femoral artery decreased in control wounds. When a disc was inserted, the blood flow was restored. NPWT causes hypoperfusion in the wound bed tissue, presumably as a result of mechanical deformation. The insertion of a rigid barrier alleviates this effect and restores blood flow.

  7. Using portable negative pressure wound therapy devices in the home care setting

    Directory of Open Access Journals (Sweden)

    Burke JR

    2014-12-01

    Full Text Available Joshua R Burke, Rachael Morley, Mustafa Khanbhai Academic Surgery Unit, Education and Research Centre, University Hospital of South Manchester, Manchester, UK Abstract: Negative pressure wound therapy (NPWT is the continuous or intermittent application of subatmospheric pressure to the surface of a wound that improves the wound environment, accelerates healing, and reduces wound closure time. Since its first documented use, this technology has lent itself to a number of adaptations, most notably, the development of portable devices facilitating treatment in the home care setting. With advancing surgical standards, wound healing is an important rate-limiting factor in early patient discharge and often a major cost of inpatient treatment. The efficacy of NPWT in the home care setting has been investigated through rate of wound closure, time in care, and patient experience. Rate of wound closure is the most appropriate primary end point. Much can be gleaned from patient experience, but the future success of portable NPWT will be measured on time in care and therefore cost effectiveness. However, there is a lack of level 1a evidence demonstrating increased efficacy of portable over inpatient NPWT. The development of portable NPWT is an encouraging innovation in wound care technology, and extending the benefits to the home care setting is both possible and potentially more beneficial. Keywords: portable, negative pressure wound therapy, vacuum-assisted closure, topical negative pressure therapy

  8. The evidence-based principles of negative pressure wound therapy in trauma & orthopedics.

    Science.gov (United States)

    A, Novak; Khan, Wasim S; J, Palmer

    2014-01-01

    Negative pressure wound therapy is a popular treatment for the management of both acute and chronic wounds. Its use in trauma and orthopedics is diverse and includes the acute traumatic setting as well as chronic troublesome wounds associated with pressure sores and diabetic foot surgery. Efforts have been made to provide an evidence base to guide its use however this has been limited by a lack of good quality evidence. The following review article explores the available evidence and describes future developments for its use in trauma and orthopaedic practice.

  9. The Evidence-Based Principles of Negative Pressure Wound Therapy in Trauma & Orthopedics

    Science.gov (United States)

    A, Novak; Khan, Wasim S; J, Palmer

    2014-01-01

    Negative pressure wound therapy is a popular treatment for the management of both acute and chronic wounds. Its use in trauma and orthopedics is diverse and includes the acute traumatic setting as well as chronic troublesome wounds associated with pressure sores and diabetic foot surgery. Efforts have been made to provide an evidence base to guide its use however this has been limited by a lack of good quality evidence. The following review article explores the available evidence and describes future developments for its use in trauma and orthopaedic practice. PMID:25067971

  10. [Negative Pressure Wound Therapy with Instillation in the Treatment of Critical Wounds].

    Science.gov (United States)

    Gathen, M; Petri, M; Krettek, C; Omar, M

    2016-04-01

    In recent decades, negative pressure wound therapy (NPWT) has become the gold standard in the treatment of infected wounds. Negative pressure wound therapy with instillation (NPWTi) is a new development, that combines conventional NPWT with instillation of fluids. The purpose of this study was to review the results of current literature on the clinical use of NPWTi in acute and chronic wounds. A literature search was performed using Pubmed and the Cochrane Library, including articles in English and German. The data suggest that NPWTi is a promising therapeutic option in the treatment of wounds, and applicable in various fields. NPWTi appears to be a useful adjunct in the treatment of critical wounds. However, data from prospective randomised trials to support the validity of the results are sparse. Georg Thieme Verlag KG Stuttgart · New York.

  11. Limitation of measurements of expiratory tidal volume and expiratory compliance under conditions of endotracheal tube leaks.

    Science.gov (United States)

    Herber-Jonat, Susanne; von Bismarck, Philipp; Freitag-Wolf, Sandra; Nikischin, Werner

    2008-01-01

    Endotracheal tube leaks (ETTLs) occur in neonates ventilated with uncuffed tubes. Assuming that the influence of ETTLs might be neglected during expiration, only expiratory tidal volume is measured for calculation of expiratory compliance in cases of large ETTLs. However, expiratory ETTL might be substantial. Therefore, we evaluated the effect of ETTL size on expiratory tidal volume and compliance. Prospective laboratory study and retrospective clinical study. University research laboratory and neonatal intensive care unit. Sixty ventilated neonates (weight 640-2160 g, gestational age 25-33 wks) were investigated. The impact of increasing ETTLs on inspiratory and expiratory measured tidal volume (Vm), corrected tidal volume (Vc), and leak volume (Vl) was investigated in a ventilated neonatal lung model. The range of ETTLs (1% to 95%) was subdivided into five groups of 12 infants each. Furthermore, the relationships between standard ETTL size and inspiratory and expiratory ETTLs were evaluated using nonlinear regression. Standard ETTL size was defined as the difference between measured inspiratory and expiratory tidal volume (Vm) related to inspiratory Vm. The size of a standard ETTL was 40% when expiratory ETTL reached 10% and was 12% when the inspiratory ETTL reached 10%. In infants, the differences between Vm and Vc were statistically significant during inspiration in the group beginning at a standard ETTL of 41% and during expiration in the group beginning at a standard ETTL of 69% (p ETTL was 33% (95% confidence interval, 28% to 36%) when expiratory ETTL reached 10% and was 13% (95% confidence interval, 12% to 15%) when inspiratory ETTL reached 10%. Expiratory Vl has a relevant impact if a certain ETTL size is reached.

  12. Silver negative pressure dressing with vacuum-assisted closure of massive pelvic and extremity wounds.

    Science.gov (United States)

    Siegel, Herrick J; Herrera, Diego F; Gay, Jason

    2014-03-01

    Massive soft tissue loss involving the pelvis and extremities from trauma, infections, and tumors remains a challenging and debilitating problem. Although vacuum-assisted closure (VAC) technology is effective in the management of soft tissue loss, the adjunct of a silver dressing in the setting of massive wounds has not been as well tested. Does a silver negative pressure dressing used in conjunction with a wound VAC decrease (1) the length of acute hospital stay and overall length of treatment; (2) the number of surgical débridements the patients underwent as part of their care; and (3) the likelihood of wound closure without soft tissue transposition? We evaluated 42 patients with massive (> 200 cm(2)) pelvic and extremity wounds from trauma, infection, or tumor who were treated with the wound VAC with or without a silver negative pressure dressing between January 2003 and January 2010; the first 26 patients were treated with the wound VAC alone, and in the final 16 consecutively treated patients, the silver dressing was added to the regimen. We reviewed medical records to determine length of treatment as well as the number and type of surgical interventions these patients underwent. We compared the group treated with the wound VAC alone with those patients treated with the wound VAC and silver negative pressure dressing. Hospital stay averaged 19 days in the VAC only group and 7.5 days in the VAC with silver dressing group (p silver dressing group (p silver dressing group (p silver dressing group (p silver negative pressure dressing in combination with the wound VAC as part of routine care of such patients. These results may be used as hypothesis-generating data for future randomized studies. Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

  13. Disagreement in primary study selection between systematic reviews on negative pressure wound therapy

    OpenAIRE

    Peinemann, Frank; McGauran, Natalie; Sauerland, Stefan; Lange, Stefan

    2008-01-01

    Abstract Background Primary study selection between systematic reviews is inconsistent, and reviews on the same topic may reach different conclusions. Our main objective was to compare systematic reviews on negative pressure wound therapy (NPWT) regarding their agreement in primary study selection. Methods This retrospective analysis was conducted within the framework of a systematic review (a full review and a subsequent rapid report) on NPWT prepared by the Institute for Quality and Efficie...

  14. Negative Pressure Wound Therapy in the Management of Combat Wounds: A Critical Review

    OpenAIRE

    Maurya, Sanjay; Bhandari, Prem Singh

    2016-01-01

    Significance: Wounds sustained in a combat trauma often result in a composite tissue loss. Combat injuries, due to high energy transfer to tissues, lead to trauma at multiple anatomical sites. An early wound cover is associated with lower rate of infections and a faster wound healing. The concept of negative pressure wound therapy (NPWT) in the management of combat-related wounds has evolved from the civilian trauma and the wounds from nontraumatic etiologies.

  15. Histomorphological observation of surgical debridement combined with negative pressure therapy in treatment of diabetic foot

    Directory of Open Access Journals (Sweden)

    Jiao-Yun Dong

    2017-08-01

    Conclusion: Epidermal cells on the fascia side of the flap could be derived from the stem cells. Negative pressure wound therapy would attract not only cells but also other elements such as growth factors, cytokines, some nutrients and extracellular matrix. With the formation of the appropriate microenvironment after debridement, the migrated cells can grow, differentiate and spread, eventually leading to the epithelization on the fascia side of the flap in diabetic foot.

  16. Wounds with complicated shapes tend to develop infection during negative pressure wound therapy

    OpenAIRE

    Fujioka, Masaki; Hayashida, Kenji; Senjyu, Chikako

    2014-01-01

    Introduction: While negative pressure wound therapy (NPWP) has been shown to be useful, we felt that patients with wounds of complicated shapes were likely to develop infection during performing NPWT. We conducted an investigation to determine the factors of wound shape responsible for the occurrence of infection. Materials and methods: A total of 55 patients with wounds were treated using NPWT in our unit in 2011. Eight whose wounds formed a pocket, 7 whose wounds were deep, and 40 whose wou...

  17. Silver Negative Pressure Dressing With Vacuum-assisted Closure of Massive Pelvic and Extremity Wounds

    OpenAIRE

    Siegel, Herrick J.; Herrera, Diego F.; Gay, Jason

    2013-01-01

    Background Massive soft tissue loss involving the pelvis and extremities from trauma, infections, and tumors remains a challenging and debilitating problem. Although vacuum-assisted closure (VAC) technology is effective in the management of soft tissue loss, the adjunct of a silver dressing in the setting of massive wounds has not been as well tested. Questions/purposes Does a silver negative pressure dressing used in conjunction with a wound VAC decrease (1) the length of acute hospital stay...

  18. Facets of negative affectivity and blood pressure in middle-aged men

    Directory of Open Access Journals (Sweden)

    Cornel V. Igna

    2013-04-01

    Full Text Available Research results suggesting that facets of negative affectivity, i.e. anxiety, anger-hostility, and depression, relate to incident cardiovascular diseases have been steadily increasing. Evidence for depression has been especially extensive. Elevated blood pressure, a major risk factor of cardiovascular diseases, is one probable mediator in this context. The purpose of this study was to clarify the relationship of specific key elements of depressive disposition, i.e. depressive symptoms, hopelessness and vital exhaustion, with health behavior and blood pressure. Study sample was comprised of 710 middle-aged men. Participants completed self-report questionnaires assessing health behavior, depressive symptoms, vital exhaustion and hopelessness. Statistical analyses involved descriptive analyses, correlations and path analysis. Depressive symptoms and vital exhaustion associated with several unfavorable lifestyles such as smoking, alcohol consumption, and inactivity (standardized solution coefficients: 0.10, 0.14, 0.17, accordingly. However, no significant direct associations with blood pressure could be found for depressive symptoms or vital exhaustion. Hopelessness associated only with unhealthy diet (standardized solution coefficient -0.10 Moreover, for hopelessness, results showed a direct but inverse association with systolic blood pressure (standardized solution coefficient -0.08. Results suggest that the previously reported relations of depression and vital exhaustion with blood pressure could be mediated by unfavorable lifestyles. The relation of hopelessness with adverse health behaviors seems to be less significant. Also, the role of hopelessness as a risk factor of elevated blood pressure is not supported by the results of this study.

  19. Use of negative pressure wound therapy with silver base dressing for necrotizing fasciitis.

    Science.gov (United States)

    Pour, Saman Mohammadi

    2011-01-01

    Necrotizing fasciitis is a life-threatening infection requiring urgent surgical and medical therapy. Hemodynamic stabilization and antimicrobial therapy precede aggressive surgical excision of necrotic tissue, which should be performed as soon as possible. The rapidly spreading infection and aggressive surgical intervention create challenges for wound management. Multiple dressings are available to address the various challenges associated with management of these wounds; this article discusses negative pressure therapy and antimicrobial dressings in the management of Fournier's gangrene, a form of necrotizing fasciitis that involves tissue of the genital or perianal areas. This article reviews the case of a 56-year-old man with fever, tachycardia, and perianal pain associated with necrotizing fasciitis. Extensive surgical debridement was done on the day of admission. After several irrigations, the wound was dressed by negative pressure wound therapy with a silver dressing that minimized hospital stay and enabled early reconstruction. We found that negative pressure wound therapy with a silver-based dressing promoted wound healing and provided a solid matrix for surgical reconstruction.

  20. Infected large pore meshes may be salvaged by topical negative pressure therapy.

    Science.gov (United States)

    Berrevoet, F; Vanlander, A; Sainz-Barriga, M; Rogiers, X; Troisi, R

    2013-02-01

    To evaluate the efficacy of negative pressure therapy for superficial and deep mesh infections after ventral and incisional hernia repair by a prospective monocentric observational study. During a 6-year period, 724 consecutive open ventral and incisional hernia repairs were performed. Pre- and intraoperative data as well as postoperative complications were prospectively recorded. In case of wound infection, negative pressure therapy (NPT) was our primary treatment. Sixty-three patients (8.7 %) were treated using negative pressure therapy after primary ventral and incisional hernia repair. Infectious complications needing NPT occurred in 54 patients in the retromuscular group (54/523; 10.3 %), none when laparoscopically treated and in 9 patients (9/143; 6.3 %) treated by an open intraperitoneal mesh technique. Considering outcome, all meshes were completely salvaged in the retromuscular mesh group after a median of 5 dressing changes (range, 2-9), while in the intraperitoneal mesh, group 3 meshes needed complete (n = 2) or partial (n = 1) excision. Mean duration to complete wound closure was 44 days (range, 26-63 days). NPT is a useful adjunct for salvage of deep infected meshes, particularly when large pore monofilament mesh is used.

  1. Using negative pressure therapy for improving skin graft taking on genital area defects following Fournier gangrene.

    Science.gov (United States)

    Orhan, Erkan; Şenen, Dilek

    2017-09-01

    Fournier's gangrene is an infective necrotizing fasciitis of the perineal, genital and perianal regions. Treatment includes aggressive surgical debridement that often results in extensive loss of genital skin. Skin grafts may be used for reconstruction but skin grafting of the male genitalia is diffucult because the penis and scrotum are mobile and deformable. A variety of methods are used to secure skin graft to recipient beds. We used negative pressure therapy (NPT) to secure skin grafts and improve skin graft taking. We used negative pressure therapy for graft fixation in 13 male patients who underwent debridements with the indication of Fournier gangrene, and whose defects formed were reconstructed with grafts between January 2009, and January 2014. Information about age of the patients, sessions of negative pressure therapy applied before, and after reconstruction, duration of hospital stay, and graft losses during postoperative period were recorded. Median age of the patients was 56.15 (46-72) years. NPT was applied to patients for an average of 6.64 sessions (4-12) before and 1 sessions after graft reconstruction. Patients were hospitalized for an average of 26.7 (20-39) days. Any graft loss was not seen after NPT. Because of the peculiar anatomy of the genital region, anchoring of grafts is difficult so graft losses are often encountered. Use of NPT for ensuring graft fixation on the genital region prevents skin graft shearing.

  2. Irrigation dynamics associated with positive pressure, apical negative pressure and passive ultrasonic irrigations: a computational fluid dynamics analysis.

    Science.gov (United States)

    Chen, José Enrique; Nurbakhsh, Babak; Layton, Gillian; Bussmann, Markus; Kishen, Anil

    2014-08-01

    Complexities in root canal anatomy and surface adherent biofilm structures remain as challenges in endodontic disinfection. The ability of an irrigant to penetrate into the apical region of a canal, along with its interaction with the root canal walls, will aid in endodontic disinfection. The aim of this study was to qualitatively examine the irrigation dynamics of syringe irrigation with different needle tip designs (open-ended and closed-ended), apical negative pressure irrigation with the EndoVac® system, and passive ultrasonic-assisted irrigation, using a computational fluid dynamics model. Syringe-based irrigation with a side-vented needle showed a higher wall shear stress than the open-ended but was localised to a small region of the canal wall. The apical negative pressure mode of irrigation generated the lowest wall shear stress, while the passive-ultrasonic irrigation group showed the highest wall shear stress along with the greatest magnitude of velocity. © 2013 The Authors. Australian Endodontic Journal © 2013 Australian Society of Endodontology.

  3. Cardiovascular regulatory response to lower body negative pressure following blood volume loss

    Science.gov (United States)

    Shimizu, M.; Ghista, D. N.; Sandler, H.

    1979-01-01

    An attempt is made to explain the cardiovascular regulatory responses to lower body negative pressure (LBNP) stress, both in the absence of and following blood or plasma volume loss, the latter being factors regularly observed with short- or long-term recumbency or weightlessness and associated with resulting cardiovascular deconditioning. Analytical expressions are derived for the responses of mean venous pressure and blood volume pooled in the lower body due to LBNP. An analysis is presented for determining the HR change due to LBNP stress following blood volume loss. It is concluded that the reduced orthostatic tolerance following long-term space flight or recumbency can be mainly attributed to blood volume loss, and that the associated cardiovascular responses characterizing this orthostatic intolerance is elicited by the associated central venous pressure response.

  4. Evaluation of negative pressure vacuum-assisted system in acute and chronic wounds closure: our experience.

    Science.gov (United States)

    Chiummariello, S; Guarro, G; Pica, A; Alfano, C

    2012-10-01

    Negative-pressure therapy or vacuum-assisted closure (VAC) has been used in clinical applications since the 1940's and has increased in popularity over the past decade. This dressing technique consists of an open cell foam dressing put into the wound cavity, a vacuum pump produces a negative pressure and an adhesive drape. A controlled sub atmospheric pressure from 75 to 150 mmHg is applied. The vacuum-assisted closure has been applied by many clinicians to chronic wounds in humans; however it cannot be used as a replacement for surgical debridement. The initial treatment for every contaminated wound should be the necrosectomy. The VAC therapy has a complementary function and the range of its indications includes pressure sores, stasis ulcers, chronic wounds such as diabetic foot ulcers, post traumatic and post operative wounds, infected wounds such as necrotizing fasciitis or sternal wounds, soft-tissue injuries, bone exposed injuries, abdominal open wounds and for securing a skin graft. We describe our experience with the VAC dressing used to manage acute and chronic wounds in a series of 135 patients, with excellent results together with satisfaction of the patients.

  5. Timer switch to convert suction apparatus for negative pressure wound therapy application

    Directory of Open Access Journals (Sweden)

    Surath Amarnath

    2014-01-01

    Full Text Available Background: Negative pressure wound therapy (NPWT is an established modality in the treatment of chronic wounds, open fractures, and post-operative wound problems. This method has not been widely used due to the high cost of equipment and consumables. This study demonstrates an indigenously developed apparatus which gives comparable results at a fraction of the cost. Readily available materials are used for the air-tight dressing. Materials and Methods: Equipment consists of suction apparatus with adjustable pressure valve set to a pressure 125-150 mmHg. An electronic timer switch with a sequential working time of 5 min and a standby time of 3 min provides the required intermittent negative pressure. Readily available materials such as polyvinyl alcohol sponge, suction drains and steridrapes were used to provide an air tight wound cover. Results: A total of 90 cases underwent 262 NPWT applications from 2009 to 2014. This series, comprised of 30 open fractures, 21 post-operative and 39 chronic wounds. The wound healing rate in our study was comparable to other published studies using NPWT. Conclusion: The addition of electronic timer switch will convert a suction apparatus into NPWT machine, and the results are equally effective compared to more expensive counter parts. The use of indigenous dressing materials reduces the cost significantly.

  6. Abdominal muscle activity during breathing with and without inspiratory and expiratory loads in healthy subjects.

    Science.gov (United States)

    Mesquita Montes, António; Baptista, João; Crasto, Carlos; de Melo, Cristina Argel; Santos, Rita; Vilas-Boas, João Paulo

    2016-10-01

    Central Nervous System modulates the motor activities of all trunk muscles to concurrently regulate the intra-abdominal and intra-thoracic pressures. The study aims to evaluate the effect of inspiratory and expiratory loads on abdominal muscle activity during breathing in healthy subjects. Twenty-three higher education students (21.09±1.56years; 8males) breathed at a same rhythm (inspiration: two seconds; expiration: four seconds) without load and with 10% of the maximal inspiratory or expiratory pressures, in standing. Surface electromyography was performed to assess the activation intensity of rectus abdominis, external oblique and transversus abdominis/internal oblique muscles, during inspiration and expiration. During inspiration, transversus abdominis/internal oblique activation intensity was significantly lower with inspiratory load when compared to without load (p=0.009) and expiratory load (p=0.002). During expiration, the activation intensity of all abdominal muscles was significantly higher with expiratory load when compared to without load (pactivation intensity of external oblique (p=0.036) and transversus abdominis/internal oblique (p=0.022) was significantly higher with inspiratory load when compared to without load. Transversus abdominis/internal oblique activation intensity was significantly higher with expiratory load when compared to inspiratory load (pmuscle to modulate the intra-abdominal pressure for the breathing mechanics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Patients' experiences of negative pressure wound therapy for the treatment of wounds: a review.

    Science.gov (United States)

    Upton, D; Stephens, D; Andrews, A

    2013-01-01

    To review the research on patients' experiences of undergoing negative pressure wound therapy (NPWT). A literature search was carried out using the following databases: Academic Search Complete, CINAHL, PsychINFO, MEDLINE, PubMed and PsyARTICLES. The search covered the period from 2001 to 2012, using the key words: ['negative pressure wound therapy' OR 'vacuum-assisted closure' OR 'topical negative therapy'] AND ['patients' experiences' OR 'psychological' OR 'stress' OR 'anxiety' OR 'wellbeing' OR 'pain' OR 'quality of life' OR 'physical']. Twenty-five relevant articles were included. NPWT is generally considered to be successful in reducing wound depth and facilitating healing. However, studies have highlighted a number of issues that need to be considered. For example, the type of dressing used during treatment can have a significant effect on patients' experience of pain. Furthermore, the NPWT system can cause patients to feel anxious due to both the patient and the health professional being unfamiliar with this form of treatment. It can also restrict patients' daily care and wider social life, which may result in a negative self-image and low self-esteem. Despite this, some studies have reported positive improvements to patients' quality of life. Additionally, since NPWT can lead to faster healing, any detrimental impact upon patients' wellbeing may be short-term and less prolonged than that of other treatments. Compared with other treatments, there is evidence to show that NPWT can lead to faster wound healing, and a reduced frequency of dressing changes and other treatments. However, there are a number of challenges with the use of NPWT, which need to be explored further so that improvements can be made. Specifically, certain aspects of NPWT may impact negatively on patients' wellbeing, albeit short-term. Therefore, research needs to explore patients' experience of NPWT throughout the treatment process and to consider how this can be improved to minimise any

  8. Faster Wound Healing With Topical Negative Pressure Therapy in Difficult-to-Heal Wounds: A Prospective Randomized Controlled Trial

    NARCIS (Netherlands)

    Laat, E.H. de; Boogaard, M.H.W.A. van den; Spauwen, P.H.M.; Kuppevelt, D.H. van; Goor, H. van; Schoonhoven, L.

    2011-01-01

    OBJECTIVE: : A randomized clinical trial was conducted to determine the effectiveness and safety of topical negative pressure therapy in patients with difficult-to-heal wounds. METHODS: : A total of 24 patients were randomly assigned to either treatment with topical negative pressure therapy or

  9. Use of tidal breathing curves for evaluating expiratory airway obstruction in infants.

    Science.gov (United States)

    Hevroni, Avigdor; Goldman, Aliza; Blank-Brachfeld, Miriam; Abu Ahmad, Wiessam; Ben-Dov, Lior; Springer, Chaim

    2018-01-15

    To evaluate tidal breathing (TB) flow-volume and flow-time curves for identification of expiratory airway obstruction in infants. Pulmonary function tests were analyzed retrospectively in 156 infants aged 3-24 months with persistent or recurrent respiratory complaints. Parameters derived from TB curves were compared to maximal expiratory flow at functional residual capacity ([Formula: see text]maxFRC) measured by rapid thoracoabdominal compression technique. Analyzed parameters were: inspiratory time (t I ), expiratory time (t E ), tidal volume, peak tidal expiratory flow (PTEF), time to peak tidal expiratory flow (t PTEF ), expiratory flow when 50% and 25% of tidal volume remains in the lungs (FEF 50 , FEF 25 , respectively), and the ratios t PTEF /t E , t I /t E , FEF 50 /PTEF, and FEF 25 /PTEF. Statistical comparisons between flow indices and TB parameters were performed using mean squared error and Pearson's sample correlation coefficient. The study population was also divided into two groups based on severity of expiratory obstruction (above or below z-score for [Formula: see text]maxFRC of -2) to generate receiver operating characteristic (ROC) curves and calculate discriminatory values between the groups. TB parameters that were best correlated to [Formula: see text]maxFRC were: t PTEF /t E , FEF 50 /PTEF, and FEF 25 /PTEF, with r = 0.61, 0.67, 0.65, respectively (p < 0.0001 for all). ROC curves for FEF 50 /PTEF, FEF 25 /PTEF and t PTEF /t E showed areas under the curve of 0.813, 0.797, and 0.796, respectively. Cutoff value z-scores of -0.35, -0.34, and -0.43 for these three parameters, respectively, showed an 86% negative predictive value for severe airway obstructions. TB curves can assist in ruling out severe expiratory airway obstruction in infants.

  10. Severe complications after negative pressure wound therapy in burned wounds: two case reports

    Directory of Open Access Journals (Sweden)

    Ren H

    2014-07-01

    Full Text Available Haitao Ren,1 Yuan Li21Department of Burns and Wound Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China; 2Department of Ultrasound, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of ChinaAbstract: We present two typical cases of severe complications (sepsis and hemorrhage after negative pressure wound therapy (NPWT in burned patients. Necrotic tissues in some deep burn wounds are difficult to judge correctly and remove thoroughly. An electrically burned blood vessel looks “intact” but can easily break. Necrotic tissue or injured blood vessels when using NPWT are dangerous, both for causing sepsis and hemorrhage. This is the first article that reports the severe complications of NPWT in burned patients. It is imperative to heed indications and avoid contraindications. Proper preparation of wound beds, close observation, and sufficient irrigation are also crucial to avoid these severe complications, and there is an urgent need to substitute the central vacuum system with the low-pressure system.Keywords: negative pressure wound therapy, complication, burn sepsis, bleeding, drainage

  11. Abdominal compartment syndrome and open abdomen management with negative pressure devices.

    Science.gov (United States)

    Surace, Alessandra; Ferrarese, Alessia; Marola, Silvia; Cumbo, Jacopo; Valentina, Gentile; Borello, Alessandro; Solej, Mario; Martino, Valter; Nano, Mario

    2015-01-01

    Abdominal compartment syndrome (ACS) is defined as an increase of intra-abdominal pressure (IAH) to values higher than 20 mmHg, associated with reduced perfusion and organ dysfunction. There is a classification of open abdomen which stratifies patients according to the natural history of improvement or clinical deterioration. The aim of treatment is to maintain the open abdomen at the lowest level and to prevent progression to a more complex level. Surgical treatment essentially consists in abdominal decompression by leaving the abdomen open. Analysis of the literature shows that negative pressure increases the rate of primary fascial closure; entero-cutaneous fistulas are seen in a minority of cases, without seeming consequence of the application of the dressing. Open abdomen management consists of three treatment stages: acute (24-48 hours), intermediate (from 48 hours to 10 days) and late or reconstruction (from 10 days to the final closure). It's important to recognize patients at risk of IAH and the first signs of ACS and intervene early with abdominal decompression if this will establish itself. Management of the open abdomen is now facilitated by negative pressure devices, which positively affect the morbidity and mortality of patients with ACS.

  12. Sterilization by negative and positive DC plasma with a micro discharge gap at atmospheric pressure

    Science.gov (United States)

    Li, Hua; Jiang, Lin-Xiu; Jiang, Yong-Rong; Zhu, Jian-Min; Chen, Zhen-Cheng

    2017-11-01

    A new needle-to-droplet electrode structure with a micro discharge gap (2 mm) was designed to achieve direct current (DC) discharge plasma in ambient air with the aim of using the plasma to sterilize liquids. Without using noble gases or an external air flow, we succeeded in generating both a negative and positive DC plasma at atmospheric pressure. The plasma was driven by a 0 to ‑20,000 V, 100 W DC power supply. A stainless steel needle with a tip diameter of ˜ 50μm and a 200-μL droplet of bacteria-containing liquid served as the electrodes. At atmospheric pressure and room temperature (23∘C), utilizing the negative DC plasma, the discharge time lasted 10 s; the results showed that the higher the discharge voltage, the more efficient the sterilization effect. Conversely, when we applied a voltage of ‑5.5 kV, we found that the sterilization effect was more efficient for longer discharge times. Our findings demonstrate that Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) can be killed in about 30 s. Our experiments show that our sterilization method required less time and was more efficient for positive than for negative DC plasma under the same conditions.

  13. Abdominal wall reconstruction for large incisional hernia restores expiratory lung function.

    Science.gov (United States)

    Jensen, Kristian K; Backer, Vibeke; Jorgensen, Lars N

    2017-02-01

    Respiratory complications secondary to intermittent intra-abdominal hypertension and/or atelectasis are common after abdominal wall reconstruction for large incisional hernias. It is unknown if the respiratory function of this patient group is affected long term or impairs activities of daily living. We hypothesized that abdominal wall reconstruction for large incisional hernia would not lead to improved, long-term pulmonary function or respiratory quality of life. Eighteen patients undergoing open abdominal wall reconstruction with mesh for a large incisional hernia (horizontal fascial defect width >10 cm) were compared with 18 patients with an intact abdominal wall who underwent colorectal resection. Patients were examined pre- and 1-year postoperatively. Examined measures included forced vital capacity, forced expiratory volume in first second, peak expiratory flow, maximal in- and expiratory mouth pressure, and 2 validated questionnaires on respiratory quality of life. In order to decrease heterogeneity, objectively examined parameters were presented relative to the predicted values, which were normality adjusted pulmonary measures. At 1-year follow-up, the abdominal wall reconstruction group showed significant improvement in percent predicted peak expiratory flow and maximal expiratory mouth pressure, whereas all other measurements of lung function remained unchanged. Respiratory quality of life did not change significantly. Patients who underwent abdominal wall reconstruction showed a significantly greater improvement of percent predicted peak expiratory flow compared with patients undergoing colorectal resection. Abdominal wall reconstruction for large incisional hernia improved long-term expiratory lung function. Respiratory quality of life did not change significantly after abdominal wall reconstruction. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. A randomized, controlled trial of negative pressure wound therapy of pressure ulcers via a novel polyurethane foam.

    Science.gov (United States)

    Wagstaff, Marcus James Dermot; Driver, Sara; Coghlan, Patrick; Greenwood, John Edward

    2014-01-01

    The objectives of the study were (1) to look for any local, clinically apparent response, within and around a debrided wound, to a novel biocompatible polyurethane foam during repeated, short-term implantation, and (2) to assess the material's efficacy as a negative pressure wound therapy (NPWT) interface compared with a widely used, commercially available foam. Twenty pressure ulcers in 18 patients underwent surgical debridement, then randomization to receive novel treatment or control foam as the wound interface for NPWT. Dressing changes every 2-3 days allowed qualitative wound assessment and quantitative measurement to compare outcomes. No adverse reaction was observed in any patient receiving the new foam. The new "novel foam" performed as a NPWT interface as effectively as the control "standard foam." In deep wounds, the new foam was easier to remove, fragmented less, and showed less retention than the control foam. No marginal in-growth occurred, making removal less traumatic and reducing bleeding from cavity wall granulations. The results support previous large animal studies, and independent ISO10993 testing, that the new foam is safe and biocompatible. Its efficacy as an NPWT interface, nontraumatic removal with low fragmentation and retention rate, favors the new material, especially in deep cavity wounds. © 2014 by the Wound Healing Society.

  15. Use of negative pressure wound therapy in the treatment of neonatal and pediatric wounds: a retrospective examination of clinical outcomes.

    Science.gov (United States)

    Baharestani, Mona Mylene

    2007-06-01

    The clinical effectiveness of negative pressure wound therapy for the management of acute and chronic wounds is well documented in the adult population but information regarding its use in the pediatric population is limited. A retrospective, descriptive study was conducted to examine the clinical outcomes of using negative pressure wound therapy in the treatment of pediatric wounds. The medical records of 24 consecutive pediatric patients receiving negative pressure wound therapy were reviewed. Demographic data, wound etiology, time to closure, closure method, duration of negative pressure wound therapy, complications, dressing change frequency, dressing type used, and pressure settings were analyzed. All categorical variables in the dataset were summarized using frequency (count and percentages) and all continuous variables were summarized using median (minimum, maximum). The 24 pediatric patients (mean age 8.5 years [range 14 days to 18 years old]) had 24 wounds - 12 (50%) were infected at baseline. Sixteen patients had hypoalbuminemia and six had exposed hardware and bone in their wounds. Twenty-two wounds reached full closure in a median time of 10 days (range 2 to 45) following negative pressure wound therapy and flap closure (11), split-thickness skin graft (three), secondary (four), and primary (four) closure. Pressures used in this population ranged from 50 to 125 mm Hg and most wounds were covered with reticulated polyurethane foam. One patient developed a fistula during the course of negative pressure wound therapy. When coupled with appropriate systemic antibiotics, surgical debridement, and medical and nutritional optimization, in this population negative pressure wound therapy resulted in rapid granulation tissue and 92% successful wound closure. Future neonatal and pediatric negative pressure wound therapy usage registries and prospective studies are needed to provide a strong evidence base from which treatment decisions can be made in the management

  16. Effect of end-expiratory lung volume on upper airway collapsibility in sleeping men and women.

    Science.gov (United States)

    Squier, Samuel B; Patil, Susheel P; Schneider, Hartmut; Kirkness, Jason P; Smith, Philip L; Schwartz, Alan R

    2010-10-01

    The relationship between changes in absolute end-expiratory lung volume (EELV) and collapsibility has not been rigorously quantified. We hypothesized that pharyngeal collapsibility varies inversely with absolute lung volume in sleeping humans during 1) conventional and 2) isovolume measurements of passive critical pressure (Pcrit). Eighteen healthy subjects (11 male, 7 female) slept in a negative pressure ventilator for measurements of pharyngeal collapsibility (Pcrit) during non-rapid eye movement sleep. EELV was 1) allowed to vary with changes in nasal pressure for conventional Pcrit measurements and 2) controlled by maintaining a fixed pressure difference across the respiratory system (P(RS)) from the nose to the body surface for isovolume Pcrit measurements at elevated EELV (P(RS) = +10 cmH(2)O), reduced EELV (P(RS) = -5 cmH(2)O), and functional residual capacity (FRC; P(RS) = 0 cmH(2)O). In each condition, the absolute EELV was determined and the corresponding Pcrit was derived from upper airway pressure-flow relationships. In the entire group, Pcrit varied inversely with EELV (P cmH(2)O/l (P cmH(2)O exhibited greater reductions in EELV and correspondingly greater decreases in the FRC isovolume compared with the conventional Pcrit (P cmH(2)O/l (P cmH(2)O, P < 0.05), implying that the men had larger lungs and more collapsible airways than the women. The ΔPcrit/ΔEELV response was independent of sex, conventional Pcrit, body mass index, and neck, waist, and hip circumferences. We conclude that Pcrit varies inversely with absolute EELV, which may lead to 1) an underestimation of the magnitude of quantitative differences in Pcrit across the spectrum from health (negative Pcrit) to disease (positive Pcrit) and 2) increases in sleep apnea susceptibility in obesity.

  17. Recent Advances on the Application of Negative Pressure External Volume Expansion in Breast Plastic Surgery.

    Science.gov (United States)

    Liu, Wenyue; Luan, Jie

    2018-02-01

    External volume expansion (EVE) has been effectively applied as an assistance to fat transplantation on breast plastic surgery. Many indicators and refinements have been made in clinical practice; meanwhile, the related mechanism and more optimized preclinical model also have been explored in experimental studies. A literature search was conducted using PubMed with the keywords: EVE, negative pressure, breast enlargement, breast augmentation, breast reconstruction, breast plastic surgery and breast aesthetic surgery. Studies dealing with the clinical and preclinical aspects of the subject and also in vitro experiments related to a certain period of negative pressure and adipose-derived cells were selected, and those only focused on negative pressure were excluded. The indications, contraindications, complications and treatments of EVE in clinical practice were summarized. The experimental studies were mainly classified into two groups (mechanical and translational) according to their contents. Mechanical studies were further divided into inference experimental validation phase studies. For the experimental validation phase, EVE was verified to promote angiogenesis, while it still remained controversial whether it would enhance adipogenesis and cell proliferation. Clinically, our experience is on the stage of exploration, and there is a lack of standardized guidelines on its clinical application. Experimentally, the previous studies showed some subtly different views on the functional mechanisms. However, it is not enough to regulate the clinical practice yet. Therefore, related basic studies and long-term clinical follow-up are needed. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  18. [Asymmetric negative pressure pulmonary edema after acute upper airway obstruction: case report].

    Science.gov (United States)

    Peixoto, Aldo José

    2002-06-01

    Negative pressure pulmonary edema after acute upper airway obstruction is a well-described event, though infrequently diagnosed and reported. This report aimed at presenting a case of upper airway obstruction negative pressure pulmonary edema following acute upper airway obstruction characterized by pulmonary edema asymmetry, being more prominent in the right lung. A 4-year-old boy, 17 kg, phisical status ASA I submitted to combined tonsillectomy, adenoidectomy and turbinate cauterization under general anesthesia with sevoflurane/nitrous oxide/O2. Surgery duration was 90 minutes without complications. During anesthetic recovery and spontaneously breathing, patient reacted to tracheal tube, which was removed. Following, ventilatory efforts resulted in chest wall retraction without apparent air movement, being impossible to ventilate him with facial mask. Symptoms evolved to severe hypoxemia (50% SpO2) requiring reintubation. At this point, it was observed that the lung was stiffer and there were bilateral rales characterizing pulmonary edema. A chest X-ray showed diffuse bilateral infiltrates, right upper lobe atelectasis and marked pulmonary edema asymmetry (right greater than left). Patient was mechanically ventilated with PEEP for 20 hours when he was extubated. There was a progressive pulmonary edema improvement and patient was discharged 48 hours later. Negative pressure pulmonary edema (NPPE) is a rare event with high morbidity risk. It is often not diagnosed and requires from the anesthesiologist an updated knowledge and adequate management. It is usually bilateral, rarely unilateral, and exceptionally asymmetric as in this case. Most cases are treated by mechanical ventilation with PEEP or CPAP without any other therapy. The prognosis is favorable, with most cases recovering within the first 24 hours.

  19. Flame Atmospheric Pressure Chemical Ionization Coupled with Negative Electrospray Ionization Mass Spectrometry for Ion Molecule Reactions

    Science.gov (United States)

    Cheng, Sy-Chyi; Bhat, Suhail Muzaffar; Shiea, Jentaie

    2017-07-01

    Flame atmospheric pressure chemical ionization (FAPCI) combined with negative electrospray ionization (ESI) mass spectrometry was developed to detect the ion/molecule reactions (IMRs) products between nitric acid (HNO3) and negatively charged amino acid, angiotensin I (AI) and angiotensin II (AII), and insulin ions. Nitrate and HNO3-nitrate ions were detected in the oxyacetylene flame, suggesting that a large quantity of nitric acid (HNO3) was produced in the flame. The HNO3 and negatively charged analyte ions produced by a negative ESI source were delivered into each arm of a Y-shaped stainless steel tube where they merged and reacted. The products were subsequently characterized with an ion trap mass analyzer attached to the exit of the Y-tube. HNO3 showed the strongest affinity to histidine and formed (Mhistidine-H+HNO3)- complex ions, whereas some amino acids did not react with HNO3 at all. Reactions between HNO3 and histidine residues in AI and AII resulted in the formation of dominant [MAI-H+(HNO3)]- and [MAII-H+(HNO3)]- ions. Results from analyses of AAs and insulin indicated that HNO3 could not only react with basic amino acid residues, but also with disulfide bonds to form [M-3H+(HNO3)n]3- complex ions. This approach is useful for obtaining information about the number of basic amino acid residues and disulfide bonds in peptides and proteins.

  20. Flame Atmospheric Pressure Chemical Ionization Coupled with Negative Electrospray Ionization Mass Spectrometry for Ion Molecule Reactions.

    Science.gov (United States)

    Cheng, Sy-Chyi; Bhat, Suhail Muzaffar; Shiea, Jentaie

    2017-07-01

    Flame atmospheric pressure chemical ionization (FAPCI) combined with negative electrospray ionization (ESI) mass spectrometry was developed to detect the ion/molecule reactions (IMRs) products between nitric acid (HNO 3 ) and negatively charged amino acid, angiotensin I (AI) and angiotensin II (AII), and insulin ions. Nitrate and HNO 3 -nitrate ions were detected in the oxyacetylene flame, suggesting that a large quantity of nitric acid (HNO 3 ) was produced in the flame. The HNO 3 and negatively charged analyte ions produced by a negative ESI source were delivered into each arm of a Y-shaped stainless steel tube where they merged and reacted. The products were subsequently characterized with an ion trap mass analyzer attached to the exit of the Y-tube. HNO 3 showed the strongest affinity to histidine and formed (M histidine -H+HNO 3 ) - complex ions, whereas some amino acids did not react with HNO 3 at all. Reactions between HNO 3 and histidine residues in AI and AII resulted in the formation of dominant [M AI -H+(HNO 3 )] - and [M AII -H+(HNO 3 )] - ions. Results from analyses of AAs and insulin indicated that HNO 3 could not only react with basic amino acid residues, but also with disulfide bonds to form [M-3H+(HNO 3 ) n ] 3- complex ions. This approach is useful for obtaining information about the number of basic amino acid residues and disulfide bonds in peptides and proteins. Graphical Abstract ᅟ.

  1. Expiratory rib cage compression in mechanically ventilated adults: systematic review with meta-analysis

    Science.gov (United States)

    Borges, Lúcia Faria; Saraiva, Mateus Sasso; Saraiva, Marcos Ariel Sasso; Macagnan, Fabrício Edler; Kessler, Adriana

    2017-01-01

    Objective To review the literature on the effects of expiratory rib cage compression on ventilatory mechanics, airway clearance, and oxygen and hemodynamic indices in mechanically ventilated adults. Methods Systematic review with meta-analysis of randomized clinical trials in the databases MEDLINE (via PubMed), EMBASE, Cochrane CENTRAL, PEDro, and LILACS. Studies on adult patients hospitalized in intensive care units and under mechanical ventilation that analyzed the effects of expiratory rib cage compression with respect to a control group (without expiratory rib cage compression) and evaluated the outcomes static and dynamic compliance, sputum volume, systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, peripheral oxygen saturation, and ratio of arterial oxygen partial pressure to fraction of inspired oxygen were included. Experimental studies with animals and those with incomplete data were excluded. Results The search strategy produced 5,816 studies, of which only three randomized crossover trials were included, totaling 93 patients. With respect to the outcome of heart rate, values were reduced in the expiratory rib cage compression group compared with the control group [-2.81 bpm (95% confidence interval [95%CI]: -4.73 to 0.89; I2: 0%)]. Regarding dynamic compliance, there was no significant difference between groups [-0.58mL/cmH2O (95%CI: -2.98 to 1.82; I2: 1%)]. Regarding the variables systolic blood pressure and diastolic blood pressure, significant differences were found after descriptive evaluation. However, there was no difference between groups regarding the variables secretion volume, static compliance, ratio of arterial oxygen partial pressure to fraction of inspired oxygen, and peripheral oxygen saturation. Conclusion There is a lack of evidence to support the use of expiratory rib cage compression in routine care, given that the literature on this topic offers low methodological quality and is inconclusive. PMID

  2. Periodic leg movement, nasal CPAP, and expiratory muscles.

    Science.gov (United States)

    Seo, Won Hee; Guilleminault, Christian

    2012-07-01

    Periodic leg movements (PLMs) may appear during nasal CPAP titration, persisting despite the elimination of hypopneas. Systematic recordings of expiratory abdominal muscles on the right and left sides with surface electromyographic (EMG) electrodes lateral to navel, and close from the lateral side of abdomen, were added during nasal CPAP titration for treatment of obstructive sleep apnea (OSA). Positive airway pressure was titrated during nocturnal polysomnography, based on analysis of the flow curve derived from the CPAP equipment and EEG analysis, including persistence of phases A2 and A3 of the cyclic alternating pattern (CAP). The requirement was to eliminate American Association of Sleep Medicine (AASM)-defined hypopnea and also flow limitation and abnormal EEG patterns. When CPAP reached valid results, it was lowered at the time of awakening by 2 or 3 cm H(2)O, and titration was performed again. Data collected during a 7-month period on adults with a prior diagnosis of OSA who had received treatment with nasal CPAP regardless of age and sex were rendered anonymous and were retrospectively rescored by a blinded investigator. Eighty-one successively seen patients with PLMs during CPAP titration were investigated. Elimination of AASM-defined hypopnea was not sufficient to eliminate the PLMs observed during the titration; higher CPAP eliminated flow limitation and CAP phases A2 and A3 and persisting PLMs. PLMs were associated with simultaneous EMG bursts in expiratory abdominal muscles. The presence of PLMs during CPAP titration indicates the persistence of sleep-disordered breathing. PLMs during CPAP titration are related to the presence of abdominal expiratory muscle activity.

  3. An Alternative Treatment Strategy for Complicated Chronic Wounds: Negative Pressure Therapy over Mesh Skin Graft

    Directory of Open Access Journals (Sweden)

    Michele Maruccia

    2017-01-01

    Full Text Available Extensive skin defect represents a real problem and major challenge in plastic and reconstructive surgery. On one hand, skin grafts offer a practical method to deal with skin defects despite their unsuitability for several complicated wounds. On the other hand, negative pressure wound therapy (NPWT, applied before skin grafting, promotes granulation tissue growth. The aim of the study is to evaluate the improvement in wound healing given by the merger of these two different approaches. We treated 23 patients for large wounds of multiple factors. Of these, 15 were treated with the application of V.A.C.® Therapy (KCI Medical S.r.l., Milan, Italy, in combination with skin grafts after a prior unsuccessful treatment of 4 weeks with mesh skin grafts and dressings. Another 8 were treated with only mesh skin graft. Pain reduction and wound area reduction were found statistically significant (p<0.0009, p<0.0001. Infection was resolved in almost all patients. According to our study, the use of the negative pressure wound therapy over mesh skin grafts is significantly effective especially in wounds resistant to conventional therapies, thereby improving the rate of skin graft take.

  4. Effect of hindlimb suspension on cardiovascular responses to sympathomimetics and lower body negative pressure

    Science.gov (United States)

    Overton, J. Michael; Tipton, Charles M.

    1990-01-01

    To determine whether hindlimb suspension is associated with the development of cardiovascular deconditioning, male rats were studied before and after undergoing one of three treatment conditions for 9 days: (1) cage control (n = 15, CON), (2) horizontal suspension (n = 15, HOZ), and (3) head-down suspension (n = 18, HDS). Testing included lower body negative pressure administered during chloralose-urethan anesthesia and graded doses of sympathomimetic agents (norepinephrine, phenylephrine, and tyramine) administered to conscious unrestrained animals. Both HDS and HOZ were associated with a small decrease in the hypotensive response to lower body negative pressure. The HOZ group, but not the HDS group, exhibited augmented reflex tachycardia. Furthermore, both HDS and HOZ groups manifested reduced pressor responses to phenylephrine after treatment. These reductions were associated with significantly attenuated increases in mesenteric vascular resistance. However, baroreflex control of heart rate was not altered by the treatment conditions. Collectively, these results indicate that 9 days of HDS in rats does not elicit hemodynamic response patterns generally associated with cardiovascular deconditioning induced by hypogravic conditions.

  5. Matching Biological Mesh and Negative Pressure Wound Therapy in Reconstructing an Open Abdomen Defect

    Directory of Open Access Journals (Sweden)

    Fabio Caviggioli

    2014-01-01

    Full Text Available Reconstruction of open abdominal defects is a clinical problem which general and plastic surgeons have to address in cooperation. We report the case of a 66-year-old man who presented an abdominal dehiscence after multiple laparotomies for a sigmoid-rectal adenocarcinoma that infiltrated into the abdominal wall, subsequently complicated by peritonitis and enteric fistula. A cutaneous dehiscence and an incontinent abdominal wall resulted after the last surgery. The abdominal wall was reconstructed using a biological porcine cross-linked mesh Permacol (Covidien Inc., Norwalk, CT. Negative Pressure Wound Therapy (NPWT, instead, was used on the mesh in order to reduce wound dimensions, promote granulation tissue formation, and obtain secondary closure of cutaneous dehiscence which was finally achieved with a split-thickness skin graft. Biological mesh behaved like a scaffold for the granulation tissue that was stimulated by the negative pressure. The biological mesh was rapidly integrated in the abdominal wall restoring abdominal wall continence, while the small dehiscence, still present in the central area, was subsequently covered with a split-thickness skin graft. The combination of these different procedures led us to solve this complicated case obtaining complete wound closure after less than 2 months.

  6. Effect of abdominal muscle training on respiratory muscle strength and forced expiratory flows in sedentary, healthy adolescents.

    Science.gov (United States)

    Rodríguez-Núñez, Iván; Navarro, Ximena; Gatica, Darwin; Manterola, Carlos

    2016-10-01

    Respiratory muscle training is the most commonly used method to revert respiratory muscle weakness; however, the effect of protocols based on non-respiratory maneuvers has not been adequately studied in the pediatric population. The objective of this study was to establish the effect of abdominal muscle training on respiratory muscle strength and forced expiratory flows in healthy adolescents. This was a quasi-experiment. The sample was made up of healthy adolescents divided into two groups: an experimental group who completed eight weeks of active abdominal muscle training, and an equivalent control group. The following indicators were measured: abdominal muscle strength, maximal inspiratory pressure, maximal expiratory pressure (MEP), peak expiratory flow, and peak cough flow, before and after protocol completion. A value of p abdominal muscle training, MEP and peak expiratory flow increased in healthy (sedentary) adolescents. Such effects were associated with intervention-induced increases in cough peak flow. Sociedad Argentina de Pediatría.

  7. Negative pressure wound therapy for serious dog bites of extremities: a prospective randomized trial.

    Science.gov (United States)

    Rui-Feng, Chen; Li-Song, Huang; Ji-Bo, Zheng; Yi-Qing, Jia; Yu-Jie, Liu; Yi, Shan

    2016-06-01

    The objectives were to investigate the emergency treatment of serious dog bite lacerations on limbs and to identify whether negative pressure wound therapy (NPWT) was beneficial in these instances. A total of 580 cases with serious limb lacerations due to dog bites were randomly divided into 2 groups. After thorough debridement, the limb lacerations of group A (n = 329) were left open. The remaining cases (n = 251) were randomly divided into 2 subgroups, group B and group C, which were treated with 125 and 75 mm Hg of continuous negative pressure, respectively. Antibiotics were only used in cases where there were systemic signs of wound infection, and were not given prophylactically. The infection rate, infection time, and healing time were analyzed. The wound infection rates of groups A, B, and C were 9.1%, 4.1%, and 3.9%, respectively. The infection times of the 3 groups were 26.3 ± 11.6, 159.8 ± 13.4, and 166.4 ± 16.2 hours, respectively. The recovery times of the infection patients in the 3 groups were 19.2 ± 4.6, 13.2 ± 2.1, and 12.7 ± 2.3 days, respectively, and in the noninfection patients, the recovery times were 15.6 ± 2.7, 10.1 ± 2.3, and 10.5 ± 1.9 days, respectively. In groups B (-125 mm Hg) and C (-75 mm Hg), the infection rate, infection time, and healing time showed no significant differences. Patients with serious dog bite laceration on limbs could benefit from NPWT. Compared with the traditional treatment of leaving the wounds open, NPWT reduced the infection rate and shortened recovery time. When NPWT was performed, low negative pressure (-75 mm Hg) had the same positive effects as high pressure (-125 mm Hg). Prophylactic antibiotics administration is not recommended for treating this kind of laceration. Therapeutic/care management, level II. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Negative Pressure Wound Therapy With Instillation: Review of Evidence and Recommendations.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Olawoye, Olayinka; Crist, Brett D; Gabriel, Allen; Galiano, Robert D; Gupta, Subhas; Lantis Ii, John C; Lavery, Lawrence; Lipsky, Benjamin A; Teot, Luc

    2015-12-01

    Negative pressure wound therapy with instillation (NPWTi) and dwell time is an adjunctive treatment modality for selected complex wounds. Because of the greater amount of research now available, a multidisciplinary expert panel comprising the fields of podiatry, plastic and general surgery, burn treatment, infectious diseases, and orthopedics was convened on July 11, 2015, to produce a summary of the data and recommendations on the use of NPWTi. The panel members each reviewed available published literature on NPWTi in the PubMed, Cochrane, and Google Scholar databases from 1 January 2012 up until 20 July 2015 using the string search term negative pressure wound therapy instillation provided by the panel moderator; there were no restrictions on the language or type of publication. Panel members discussed their experiences and worked to reach consensus on several predefined topics. NPWTi was found to be most appropriate for properly selected complex hosts or wounds such as patients with multiple comorbidities, patients with an American Society of Anesthesiology Classification ≥ 2, severe traumatic wounds, diabetic foot infections, and wounds complicated by invasive infection or extensive biofilm. NPWTi should not be used routinely to treat simple wounds or hosts without comorbidities.There is evidence that when NPWTi is added to standard of care in properly selected cases it provides better overall clinical outcomes than standard of care alone, even when including NPWT. Based on published evidence and panel member experience, the Panel recommends a dwell time - fluid briefly instilled into the wound and allowed to diffuse for a user-specified time - of 10-20 minutes followed by 2-4 hours of negative pressure at -125 mmHg, although larger wounds may need times of up to 6 hours. Normal saline (0.9%) is the preferred solution for NPWTi, except in special situations. NPWTi with dwell time is an adjunct to other standard principles of appropriate wound assessment and

  9. Increase in vagal activity during hypotensive lower-body negative pressure in humans

    DEFF Research Database (Denmark)

    Sander-Jensen, K; Mehlsen, J; Stadeager, C

    1988-01-01

    Progressive central hypovolemia is characterized by a normotensive, tachycardic stage followed by a reversible, hypotensive stage with slowing of the heart rate (HR). We investigated circulatory changes and arterial hormone concentrations in response to lower-body negative pressure (LBNP) in six...... volunteers before and after atropine administration. LBNP of 55 mmHg initially resulted in an increase in HR from 55 +/- 4 to 90 +/- 5 beats/min and decreases in mean arterial pressure (MAP) from 94 +/- 4 to 81 +/- 5 mmHg, in central venous pressure from 7 +/- 1 to -3 +/- 1 mmHg, and in cardiac output from 6.......1 +/- 0.5 to 3.7 +/- 0.11/min. Concomitantly, epinephrine and norepinephrine levels increased. After 8.2 +/- 2.3 min of LBNP, the MAP had decreased to 41 +/- 7 mmHg and HR had decreased to 57 +/- 3 beats/min. Vasopressin increased from 1.2 +/- 0.3 to 137 +/- 45 pg/ml and renin activity increased from 1...

  10. Peak expiratory flow rates produced with the Laerdal and Mapleson-C bagging circuits.

    Science.gov (United States)

    Jones, A; Hutchinson, R; Lin, E; Oh, T

    1992-01-01

    This study compared the peak expiratory flow rates (PEFR) at different inspiratory pause pressures (IPP) produced by the Mapleson-C circuit and the Laerdal self-inflating resuscitator. The difference in PEFR produced by the two circuits was significantly different at the lowest and the highest IPP studied (I3 and 38cm H20). The greatest differences in the mean expiratory flow rates produced was, however, only 0.07 litre sec(-7). The authors suggest that the choice of bagging circuit should depend on the experience and familiarity of the therapist with the circuit. Copyright © 1992 Australian Physiotherapy Association. Published by . All rights reserved.

  11. Validation of lower body negative pressure as an experimental model of hemorrhage

    Science.gov (United States)

    Shade, Robert E.; Muniz, Gary W.; Bauer, Cassondra; Goei, Kathleen A.; Pidcoke, Heather F.; Chung, Kevin K.; Cap, Andrew P.; Convertino, Victor A.

    2013-01-01

    Lower body negative pressure (LBNP), a model of hemorrhage (Hem), shifts blood to the legs and elicits central hypovolemia. This study compared responses to LBNP and actual Hem in sedated baboons. Arterial pressure, pulse pressure (PP), central venous pressure (CVP), heart rate, stroke volume (SV), and +dP/dt were measured. Hem steps were 6.25%, 12.5%, 18.75%, and 25% of total estimated blood volume. Shed blood was returned, and 4 wk after Hem, the same animals were subjected to four LBNP levels which elicited equivalent changes in PP and CVP observed during Hem. Blood gases, hematocrit (Hct), hemoglobin (Hb), plasma renin activity (PRA), vasopressin (AVP), epinephrine (EPI), and norepinephrine (NE) were measured at baseline and maximum Hem or LBNP. LBNP levels matched with 6.25%, 12.5%, 18.75%, and 25% hemorrhage were −22 ± 6, −41 ± 7, −54 ± 10, and −71 ± 7 mmHg, respectively (mean ± SD). Hemodynamic responses to Hem and LBNP were similar. SV decreased linearly such that 25% Hem and matching LBNP caused a 50% reduction in SV. Hem caused a decrease in Hct, Hb, and central venous oxygen saturation (ScvO2). In contrast, LBNP increased Hct and Hb, while ScvO2 remained unchanged. Hem caused greater elevations in AVP and NE than LBNP, while PRA, EPI, and other hematologic indexes did not differ between studies. These results indicate that while LBNP does not elicit the same effect on blood cell loss as Hem, LBNP mimics the integrative cardiovascular response to Hem, and validates the use of LBNP as an experimental model of central hypovolemia associated with Hem. PMID:24356525

  12. Cardiovascular response to lower body negative pressure stimulation before, during, and after space flight

    Science.gov (United States)

    Baisch, F.; Beck, L.; Blomqvist, G.; Wolfram, G.; Drescher, J.; Rome, J. L.; Drummer, C.

    2000-01-01

    BACKGROUND: It is well known that space travel cause post-flight orthostatic hypotension and it was assumed that autonomic cardiovascular control deteriorates in space. Lower body negative pressure (LBNP) was used to assess autonomic function of the cardiovascular system. METHODS: LBNP tests were performed on six crew-members before and on the first days post-flight in a series of three space missions. Additionally, two of the subjects performed LBNP tests in-flight. LBNP mimics fluid distribution of upright posture in a gravity independent way. It causes an artificial sequestration of blood, reduces preload, and filtrates plasma into the lower part of the body. Fluid distribution was assessed by bioelectrical impedance and anthropometric measurements. RESULTS: Heart rate, blood pressure, and total peripheral resistance increased significantly during LBNP experiments in-flight. The decrease in stroke volume, the increased pooling of blood, and the increased filtration of plasma into the lower limbs during LBNP indicated that a plasma volume reduction and a deficit of the interstitial volume of lower limbs rather than a change in cardiovascular control was responsible for the in-flight response. Post-flight LBNP showed no signs of cardiovascular deterioration. The still more pronounced haemodynamic changes during LBNP reflected the expected behaviour of cardiovascular control faced with less intravascular volume. In-flight, the status of an intra-and extravascular fluid deficit increases sympathetic activity, the release of vasoactive substances and consequently blood pressure. Post-flight, blood pressure decreases significantly below pre-flight values after restoration of volume deficits. CONCLUSION: We conclude that the cardiovascular changes in-flight are a consequence of a fluid deficit rather than a consequence of changes in autonomic signal processing.

  13. Efficacy and safety of negative pressure wound therapy for Szilagyi grade III peripheral vascular graft infection.

    Science.gov (United States)

    Cheng, Hsu-Tang; Hsu, Yung-Chang; Wu, Chao-I

    2014-12-01

    A best evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether it is safe and effective to use negative pressure wound therapy (NPWT) for Szilagyi grade III (i.e. the arterial implant proper involved in the infection) peripheral vascular graft infection. Altogether, 69 papers were found using the reported search. From the search results, reference lists of potentially eligible studies and related citations in PubMed, seven papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. In the only randomized, controlled trial that compared NPWT (n = 10) and alginate dressing change (n = 10), the NPWT group demonstrated shorter time to full skin epithelialization (median 57 vs 104 days; P = 0.026). In the other six case series, the recruited case number ranged from 12 to 72. The mode of NPWT varied among the included studies, with the majority using a continuous negative pressure of 125 mmHg. One study combined NPWT and sartorius myoplasty, another used sartorius myoplasty in selected cases and others did not. The mean duration of using NPWT ranged from 14.2 to 43 days. The mean duration to achieve complete wound healing ranged from 24 (the study with sartorius myoplasty) to 51 days. The NPWT treatment failure rate ranged from 0 (the study with sartorius myoplasty) to 25%. The major complication of NPWT was bleeding and the incidence rate was reported to be 1 year of follow-up) showed that NPWT with a continuous negative pressure of 125 mmHg, or combined NPWT and sartorius myoplasty, may shorten the time to complete wound healing by 2 months, have a >70% success rate, and have a <10% NPWT-related complication rate. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights

  14. Historical Review of Lower Body Negative Pressure Research in Space Medicine.

    Science.gov (United States)

    Campbell, Mark R; Charles, John B

    2015-07-01

    Cephalad redistribution of intravascular and extravascular fluid occurs as a result of weightlessness during spaceflight. This provokes cardiovascular, cardiopulmonary, and autonomic nervous system responses. The resulting altered functional state can result in orthostatic hypotension and intolerance upon landing and return to a gravity environment. In-flight lower body negative pressure (LBNP) transiently restores normal body fluid distribution. Early in the U.S. space program, LBNP was devised as a way to test for orthostatic intolerance. With the development of the Skylab Program and longer duration spaceflight, it was realized that it could provide a method of monitoring orthostatic intolerance in flight and predicting the post-landing orthostatic response. LBNP was also investigated not only as an in-flight cardiovascular orthostatic stress test, but also as a countermeasure to cardiovascular deconditioning on Soviet space stations, Skylab, and the Shuttle. It is still being used by the Russian program on the International Space Station as an end-of-flight countermeasure.

  15. Effects of regional hemoconcentration during LBNP on plasma volume determinations. [Lower Body Negative Pressure

    Science.gov (United States)

    Loeppky, J. A.; Kobayashi, Y.; Venters, M. D.; Luft, U. C.

    1979-01-01

    Blood samples were obtained from forearm vein or artery with indwelling cannula (1) before, (2) during the last min, and (3) about 2 min after lower body negative pressure (LBNP) in 16 experiments to determine whether plasma volume (PV) estimates were affected by regional hemoconcentration in the lower body. Total hemoglobin (THb) was estimated with the CO method prior to LBNP. Hemoglobin (Hb) and hematocrit (Hct) values from (2) gave only a 3% (87 ml) loss in PV due to LBNP, assuming no change in THb. However, Hb and Hct values from (3) showed an 11% loss in PV (313 ml). This 72% underestimation of PV loss with (2) must have resulted from the sequestration of blood and subsequent hemoconcentration in the lower body during LBNP. The effects of LBNP on PV should be estimated 1-3 min after exposure, after mixing but before extravascular fluid returns to the circulation.

  16. Negative pressure wound therapy in pediatric surgery: How and when to use.

    Science.gov (United States)

    de Jesus, Lisieux Eyer; Martins, Alana Bandeira; Oliveira, Pablo Baptista; Gomes, Fernanda; Leve, Thais; Dekermacher, Samuel

    2018-04-01

    Negative pressure wound therapy (NPWT) has been widely adopted to treat laparostomy, abdominal compartment syndrome (ACS) and complicated wounds associated with tissue loss. The method presents specific aspects, advantages and indications in Pediatrics. Our aim is to review the evidence available about NPWT in children. Active search for papers about NPWT in Pediatric patients. Papers referring to orthopedic problems, wound complications after Cardiac Surgery or burns were excluded. The method shows good results to treat ACS, complicated wounds and abdominal wall malformations in neonates, including prematures. Periwound skin protection, monitoring of fluid losses and fine tuning of negative pressure levels according to age are necessary. Less pain, quicker recovery, less frequent dressing changes, possible recovery of exposed surgical hardware, granulation and shrinkage of the wound are advantages of the method over other kinds of dressing. NPWT is contraindicated over blood vessels and exposed nerves. Debridement is needed before usage over necrotic areas. Enteric fistulae are not contraindications. Complications are rare, mainly foam retention and dermatitis/skin maceration. The possibility of fistulae being caused by NPWT remains debatable. NPWT is widely used in Pediatrics, including neonates and premature, but the evidence available about the method is scarce and low quality. Complications are uncommon and mostly manageable. A possible causal relationship between NPWY and enteric fistula remains unclear. Adult devices and parameters have been adapted to children's use. Extra care is needed to protect the delicate tissues of Pediatric patients. Comparative research to define differential costs, indications and advantages of the method, specific indications and limits of NWTP in Pediatrics is needed. Review. IV. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Intrarectal negative pressure system in the management of open abdomen with colorectal fistula: A case report☆

    Science.gov (United States)

    Yetişir, Fahri; Salman, A. Ebru; Mamedov, Ruslan; Aksoy, Mustafa; Yalcin, Abdussamet; Kayaalp, Cüneyt

    2014-01-01

    INTRODUCTION To present the management of open abdomen with colorectal fistula by application of intrarectal negative pressure system (NPS) in addition to abdominal NPS. PRESENTATION OF CASE Twenty-year old man had a history of injuries by a close-range gunshot to the abdomen eight days ago and he had been treated by bowel repairs, resections, jejunal anastomosis and Hartman's procedure. He was referred to our center after deterioration, evisceration with open abdomen and enteric fistula in septic shock. There were edematous, fibrinous bowels and large multiple fistulas from the edematous rectal stump. APACHE II, Mannheim Peritoneal Index and Björck scores were 18, 33 and 3, respectively (expected mortality 100%). After intensive care for 5 days, he was treated by abdominal and intrarectal NPS. NPS repeated for 5 times and the fistula was recovered on day 18 completely. Fascial closure was facilitated with a dynamic abdominal closure system (ABRA) and he was discharged on day 33 uneventfully. There was no herniation and any other problem after 12 months follow-up. DISCUSSION Management of fistula in OA can be extremely challenging. Floating stoma, fistula VAC, nipple VAC, ring and silo VAC, fistula intubation systems are used for isolation of the enteric effluent from OA. Several biologic dressings such as acellular dermal matrix, pedicled flaps have been used to seal the fistula opening with various success. Resection of the involved enteric loop and a new anastomosis of the intestine is very hard and rarely possible. In all of these reports, usually patients are left to heal with a giant hernia. In contrast to this, there is no hernia in our case during one year follow up period. CONCLUSION Combination of intra and extra luminal negative pressure systems and ABRA is a safe and successful method to manage open abdomen with colorectal fistula. PMID:24584042

  18. Intrarectal negative pressure system in the management of open abdomen with colorectal fistula: A case report.

    Science.gov (United States)

    Yetişir, Fahri; Salman, A Ebru; Mamedov, Ruslan; Aksoy, Mustafa; Yalcin, Abdussamet; Kayaalp, Cüneyt

    2014-01-01

    To present the management of open abdomen with colorectal fistula by application of intrarectal negative pressure system (NPS) in addition to abdominal NPS. Twenty-year old man had a history of injuries by a close-range gunshot to the abdomen eight days ago and he had been treated by bowel repairs, resections, jejunal anastomosis and Hartman's procedure. He was referred to our center after deterioration, evisceration with open abdomen and enteric fistula in septic shock. There were edematous, fibrinous bowels and large multiple fistulas from the edematous rectal stump. APACHE II, Mannheim Peritoneal Index and Björck scores were 18, 33 and 3, respectively (expected mortality 100%). After intensive care for 5 days, he was treated by abdominal and intrarectal NPS. NPS repeated for 5 times and the fistula was recovered on day 18 completely. Fascial closure was facilitated with a dynamic abdominal closure system (ABRA) and he was discharged on day 33 uneventfully. There was no herniation and any other problem after 12 months follow-up. Management of fistula in OA can be extremely challenging. Floating stoma, fistula VAC, nipple VAC, ring and silo VAC, fistula intubation systems are used for isolation of the enteric effluent from OA. Several biologic dressings such as acellular dermal matrix, pedicled flaps have been used to seal the fistula opening with various success. Resection of the involved enteric loop and a new anastomosis of the intestine is very hard and rarely possible. In all of these reports, usually patients are left to heal with a giant hernia. In contrast to this, there is no hernia in our case during one year follow up period. Combination of intra and extra luminal negative pressure systems and ABRA is a safe and successful method to manage open abdomen with colorectal fistula. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Analysis of Effective Interconnectivity of DegraPol-foams Designed for Negative Pressure Wound Therapy

    Directory of Open Access Journals (Sweden)

    Heike Hall

    2009-03-01

    Full Text Available Many wounds heal slowly and are difficult to manage. Therefore Negative Pressure Wound Therapy (NPWT was developed where polymer foams are applied and a defined negative pressure removes wound fluid, reduces bacterial burden and increases the formation of granulation tissue. Although NPWT is used successfully, its mechanisms are not well understood. In particular, different NPWT dressings were never compared. Here a poly-ester urethane Degrapol® (DP-foam was produced and compared with commercially available dressings (polyurethane-based and polyvinyl-alcohol-based in terms of apparent pore sizes, swelling and effective interconnectivity of foam pores. DP-foams contain relatively small interconnected pores; PU-foams showed large pore size and interconnectivity; whereas PVA-foams displayed heterogeneous and poorly interconnected pores. PVA-foams swelled by 40 %, whereas DP- and PU-foams remained almost without swelling. Effective interconnectivity was investigated by submitting fluorescent beads of 3, 20 and 45 mm diameter through the foams. DP- and PU-foams removed 70-90 % of all beads within 4 h, independent of the bead diameter or bead pre-adsorption with serum albumin. For PVA-foams albumin pre-adsorbed beads circulated longer, where 20 % of 3 mm and 10 % of 20 mm diameter beads circulated after 96 h. The studies indicate that efficient bead perfusion does not only depend on pore size and swelling capacity, but effective interconnectivity might also depend on chemical composition of the foam itself. In addition due to the efficient sieve-effect of the foams uptake of wound components in vivo might occur only for short time suggesting other mechanisms being decisive for success of NPWT.

  20. Fluid Shifts: Otoacoustical Emission Changes in Response to Posture and Lower Body Negative Pressure

    Science.gov (United States)

    Melgoza, R.; Kemp, D.; Ebert, D.; Danielson, R.; Stenger, M.; Hargens, A.; Dulchavsky, S.

    2016-01-01

    INTRODUCTION: The purpose of the NASA Fluid Shifts Study is to characterize fluid distribution and compartmentalization associated with long-duration spaceflight and to correlate these findings with vision changes and other elements of the visual impairment and intracranial pressure (VIIP) syndrome. VIIP signs and symptoms, as well as postflight lumbar puncture data, suggest that elevated intracranial pressure (ICP) may be associated with spaceflight-induced cephalad fluid shifts, but this hypothesis has not been tested. Due to the invasive nature of direct measures of ICP, a noninvasive technique of monitoring ICP is desired for use during spaceflight. The phase angle and amplitude of otoacoustic emissions (OAEs) have been shown to be sensitive to posture change and ICP (1, 2), therefore use of OAEs is an attractive option. OAEs are low-level sounds produced by the sensory cells of the cochlea in response to auditory stimulation. These sounds travel peripherally from the cochlea, through the oval window, to the ear canal where they can be recorded. OAE transmission is sensitive to changes in the stiffness of the oval window, occurring as a result of changes in cochlear pressure. Increased stiffness of the oval window largely affects the transmission of sound from the cochlea at frequencies between 800 Hz and 1600 Hz. OAEs can be self-recorded in the laboratory or on the ISS using a handheld device. Our primary objectives regarding OAE measures in this experiment were to 1) validate this method during preflight testing of each crewmember (while sitting, supine and in head-down tilt position), and 2) determine if OAE measures (and presumably ICP) are responsive to lower body negative pressure and to spaceflight. METHODS: Distortion-product otoacoustic emissions (DPOAEs) and transient evoked otoacoustic emissions (TEOAEs) were recorded preflight using the Otoport Advance OAE system (Otodynamics Ltd., Hatfield, UK). Data were collected in four conditions (seated

  1. Development of micropump-actuated negative pressure pinched injection for parallel electrophoresis on array microfluidic chip.

    Science.gov (United States)

    Li, Bowei; Jiang, Lei; Xie, Hua; Gao, Yan; Qin, Jianhua; Lin, Bingcheng

    2009-09-01

    A micropump-actuated negative pressure pinched injection method is developed for parallel electrophoresis on a multi-channel LIF detection system. The system has a home-made device that could individually control 16-port solenoid valves and a high-voltage power supply. The laser beam is excitated and distributes to the array separation channels for detection. The hybrid Glass-PDMS microfluidic chip comprises two common reservoirs, four separation channels coupled to their respective pneumatic micropumps and two reference channels. Due to use of pressure as a driving force, the proposed method has no sample bias effect for separation. There is only one high-voltage supply needed for separation without relying on the number of channels, which is significant for high-throughput analysis, and the time for sample loading is shortened to 1 s. In addition, the integrated micropumps can provide the versatile interface for coupling with other function units to satisfy the complicated demands. The performance is verified by separation of DNA marker and Hepatitis B virus DNA samples. And this method is also expected to show the potential throughput for the DNA analysis in the field of disease diagnosis.

  2. Cardiovascular responses of men and women to lower body negative pressure

    Science.gov (United States)

    Montgomery, L. D.; Kirk, P. J.; Payne, P. A.; Gerber, R. L.; Newton, S. D.; Williams, B. A.

    1977-01-01

    Changes in blood flow and blood redistribution were measured by impedance plethysmography in the pelvic and leg regions of six male and four female subjects during three 5-min exposures to -20, -40, and -60 mm Hg lower body negative pressure (LBNP). Female subjects demonstrated significantly higher mean heart rate and lower leg blood flow indices than the male subjects during the recumbent control periods. Men had slightly higher mean resting systolic and diastolic blood pressures and higher mean control pelvic blood indices. Women demonstrated significantly less blood pooling in the legs and slightly less in the pelvic region than the men. All of the 18 tests with male subjects at -60 mm Hg were completed without initial signs of syncope, while only two of the tests with women were completed successfully without the subject exhibiting presyncopal conditions. Results indicate that impedance plethysmography can be used to measure segmental cardiovascular responses during LBNP and that females may be less tolerant to -60 mm Hg LBNP than males.

  3. Cardiovascular regulation in humans in response to oscillatory lower body negative pressure

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    Levenhagen, D. K.; Evans, J. M.; Wang, M.; Knapp, C. F.

    1994-01-01

    The frequency response characteristics of human cardiovascular regulation during hypotensive stress have not been determined. We therefore exposed 10 male volunteers to seven frequencies (0.004-0.1 Hz) of oscillatory lower body negative pressure (OLBNP; 0-50 mmHg). Fourier spectra of arterial pressure (AP), central venous pressure (CVP), stroke volume (SV), cardiac output (CO), heart rate (HR), and total peripheral resistance (TPR) were determined and first harmonic mean, amplitude, and phase angles with respect to OLBNP are presented. AP was relatively well regulated as demonstrated by small oscillations in half amplitude (3.5 mmHg) that were independent of OLBNP frequency and similar to unstressed control spectra. Due to the biomechanics of the system, the magnitudes of oscillations in calf circumference (CC) and CVP decreased with increasing frequency; therefore, we normalized responses by these indexes of the fluid volume shifted. The ratios of oscillations in AP to oscillations in CC increased by an order of magnitude, whereas oscillations in CVP to oscillations in CC and oscillations in AP to oscillations in CVP both tripled between 0.004 and 0.1 Hz. Therefore, even though the amount of fluid shifted by OLBNP decreased with increasing frequency, the magnitude of both CVP and AP oscillations per volume of fluid shifted increased (peaking at 0.08 Hz). The phase relationships between variables, particularly the increasing lags in SV and TPR, but not CVP, indicated that efferent responses with lags of 5-6 s could account for the observed responses. We conclude that, at frequencies below 0.02 Hz, the neural system of humans functioned optimally in regulating AP; OLBNP-induced decreases in SV (by as much as 50%) were counteracted by appropriate oscillations in HR and TPR responses. As OLBNP frequency increased, SV, TPR, and HR oscillations increasingly lagged the input and became less optimally timed for AP regulation.

  4. Effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by parkinson's disease.

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    Byeon, Haewon

    2016-06-01

    [Purpose] This study aimed to investigate the effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by Parkinson's disease. [Subjects and Methods] The subjects of this study were 18 patients who received simultaneous application of postural techniques and expiratory muscle strength training and 15 patients who received expiratory muscle strength training only. Postural techniques were conducted in the order of chin tucking, head rotation, head tilting, bending head back, and lying down, while expiratory muscle strength training was conducted at a resistance level of about 70% of the maximal expiratory pressure. Swallowing recovery was assessed by using the Functional Dysphagia Scale based on videofluoroscopic studies. [Results] The mean value obtained in the videofluoroscopic studies for both groups decreased after the treatment. In the postural techniques plus expiratory muscle strength training group, the decrease was significantly greater than that in the expiratory muscle strength training-only group. [Conclusion] The results imply that simultaneous performance of postural techniques and expiratory muscle strength training is more effective than expiratory muscle strength training alone when applied in the swallowing rehabilitation for patients with dysphagia caused by Parkinson's disease.

  5. Exploiting potency of negative pressure in wound dressing using limited access dressing and suction-assisted dressing

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    Pramod Kumar

    2012-01-01

    Full Text Available Role of negative pressure dressing and moist wound healing are well established in the treatment of both acute and chronic wounds with certain advantages and disadvantages in both the techniques. Both these techniques prevents wound colonization, but the negative pressure dressing method has proved to have a greater potency to remove secretions, prevent wound invasion and eradication established infection. In both these techniques there is no accessibility to wound environment. Limited access dressing (LAD is a moist wound dressing with negative pressure. It provides limited access to the wound through two small ports for both dressers and pathogens. The LAD design has notable advantages like wound isolation that reduces chance of wound colonization and safe disposal of infected materials (important factor to reduce hospital-acquired infections, while avoiding some major disadvantages such as opacity of dressing materials, inaccessible offensive smelling wound environment, and relatively high treatment costs. In LAD a definite intermittent negative pressure regimen is followed. The intermittent negative pressure (cycle of 30 minutes suction and 3 1 / 2 hours rest is effective. Overall, the LAD is a safe and effective alternative to conventional dressing methods. LAD is an excellent research tool for wound healing as frequent/continuous record of wound healing is possible without disturbing the wound healing process. LAD is an effective dressing for limb salvage in cases of acute and chronic complex wounds. Leech effect prevents wound related systematic response syndrome and sepsis. Suction-assisted dressing (SAD is a combination of semiocclusive dressing with negative pressure. It works by removal of fluids by intermittent (like LAD negative pressure and preventing bacterial invasion. SAD is especially advantageous where soakage is less, there is no dead tissue covering the wound (e.g., following skin grafting, superficial skin wounds (e

  6. Pressão expiratória positiva nas vias aéreas não reproduz as respostas de frequência cardíaca à manobra de Valsalva em homens jovens saudáveis Expiratory positive airway pressure does not reproduce heart rate responses to Valsalva maneuver in healthy young men

    Directory of Open Access Journals (Sweden)

    Isabella Gracindo Pissinato

    2012-06-01

    Full Text Available A pressão expiratória positiva nas vias aéreas (EPAP é um recurso terapêutico que compreende uma inspiração seguida de expiração contra resistência. Sua aplicação promove ajustes no sistema cardiovascular, de maneira similar ao observado durante a manobra de Valsalva (MV. O objetivo deste estudo foi analisar a resposta da frequência cardíaca (FC à MV e às diferentes formas de aplicação de EPAP a fim de identificar se e em qual condição esta técnica reproduz a resposta da FC observada na MV, em homens jovens aparentemente saudáveis. Foram estudados 10 sujeitos (24±3 anos; 25±3 kg/m² que realizaram os procedimentos de MV e EPAP, aleatoriamente em dias diferentes. Na MV o esforço expiratório foi sustentado por 15 s (pressão oral de 40 mmHg [53,4 cmH2O]. Empregou-se duas técnicas de EPAP (isolada e terapêutica contra 3 níveis de pressão (10, 15 e 20 cmH2O, aplicados aleatoriamente. As manobras foram repetidas três vezes com intervalo de cinco minutos. Considerou-se o maior valor de variação da FC (DFC de cada manobra para análise. Empregou-se o teste Shapiro-Wilk para verificar a distribuição dos dados e ANOVA para medidas repetidas, com post-hoc de Fisher, considerando-se αThe expiratory positive airway pressure (EPAP is a therapeutic resource that comprises an inspiration followed by expiration against resistance. During its application there were adjustments in the cardiovascular system, similar to those observed during the Valsalva maneuver (VM. The aim of this study was to analyze the heart rate (HR response to VM and to different ways of EPAP application to identify if and in which condition this technique reproduces the HR response observed in the VM, in apparently healthy young men. Ten subjects (24±3 years, 25±3 kg/m² performed randomly the VM and EPAP procedures on different days. The expiratory effort in VM was sustained for 15 s (oral pressure of 40 mmHg [53.4cm H2O]. Two EPAP techniques were

  7. Influence of inspiratory resistive loading on expiratory muscle fatigue in healthy humans.

    Science.gov (United States)

    Peters, Carli M; Welch, Joseph F; Dominelli, Paolo B; Molgat-Seon, Yannick; Romer, Lee M; McKenzie, Donald C; Sheel, A William

    2017-09-01

    What is the central question of this study? This study is the first to measure objectively both inspiratory and expiratory muscle fatigue after inspiratory resistive loading to determine whether the expiratory muscles are activated to the point of fatigue when specifically loading the inspiratory muscles. What is the main finding and its importance? The absence of abdominal muscle fatigue suggests that future studies attempting to understand the neural and circulatory consequences of diaphragm fatigue can use inspiratory resistive loading without considering the confounding effects of abdominal muscle fatigue. Expiratory resistive loading elicits inspiratory as well as expiratory muscle fatigue, suggesting parallel coactivation of the inspiratory muscles during expiration. It is unknown whether the expiratory muscles are likewise coactivated to the point of fatigue during inspiratory resistive loading (IRL). The purpose of this study was to determine whether IRL elicits expiratory as well as inspiratory muscle fatigue. Healthy male subjects (n = 9) underwent isocapnic IRL (60% maximal inspiratory pressure, 15 breaths min -1 , 0.7 inspiratory duty cycle) to task failure. Abdominal and diaphragm contractile function was assessed at baseline and at 3, 15 and 30 min post-IRL by measuring gastric twitch pressure (P ga,tw ) and transdiaphragmatic twitch pressure (P di,tw ) in response to potentiated magnetic stimulation of the thoracic and phrenic nerves, respectively. Fatigue was defined as a significant reduction from baseline in P ga,tw or P di,tw . Throughout IRL, there was a time-dependent increase in cardiac frequency and mean arterial blood pressure, suggesting activation of the respiratory muscle metaboreflex. The P di,tw was significantly lower than baseline (34.3 ± 9.6 cmH 2 O) at 3 (23.2 ± 5.7 cmH 2 O, P muscle fatigue. Agonist-antagonist interactions for the respiratory muscles appear to be more important during expiratory versus inspiratory

  8. Comparação entre inspirometria de incentivo e pressão positiva expiratória na função pulmonar após cirurgia bariátrica Comparison between incentive spirometry and expiratory positive airway pressure on pulmonary function after bariatric surgery

    Directory of Open Access Journals (Sweden)

    Marcela C. Barbalho-Moulim

    2009-06-01

    Full Text Available O objetivo deste estudo foi comparar o efeito da pressão positiva expiratória (EPAP, na sigla em inglês e da inspirometria de incentivo a fluxo sobre a função pulmonar após o bypass gástrico em Y de Roux por videolaparoscopia. Participaram 28 mulheres, não-tabagistas e não-pneumopatas, com índice de massa corporal entre 35 e 50 kg/m², submetidas à cirurgia bariátrica. Todas foram avaliadas por espirometria, cirtometria toracoabdominal e quanto à mobilidade diafragmática no pré e segundo dia de pós-operatório (o tempo de internação foi de 2 dias. Foram divididas em dois grupos, GI - grupo inspirômetro (n=13 e GE, grupo EPAP (n=15. A fisioterapia foi iniciada no dia da cirurgia, cada técnica, inspirometria ou EPAP, com duração de 15 minutos; a fisioterapia motora foi padronizada para ambos os grupos. No pós-operatório, houve redução similar nos dois grupos das variáveis: capacidade vital, volume de reserva inspiratório, capacidade vital forçada e ventilação voluntária máxima. Não houve alteração nos valores do volume corrente no GI e volume de reserva expiratório no GE. A mobilidade diafragmática e a mobilidade toracoabdominal foram menos prejudicadas no GI. No pós-operatório da cirurgia bariátrica por videolaparoscopia, a inspirometria de incentivo a fluxo exerceu melhores efeitos na manutenção do volume corente, na mobilidade diafragmática e toracoabdominal, enquanto a EPAP foi mais eficaz no restabelecimento do volume de reserva expiratório.The aim of this study was to compare the effect of expiratory positive airway pressure (EPAP and flow-oriented incentive spirometry on pulmonary function after laparoscopic Roux-en-Y gastric bypass surgery. Twenty-eight non-smoking women, with no lung disease and body mass index of 35 to 50 kg/m², undergoing laparoscopic gastric bypass surgery (hospitalized for two days were assessed by spirometry, thoracoabdominal cirtometry and as to diaphragmatic motion

  9. Therapy of acute and delayed spinal infections after spinal surgery treated with negative pressure wound therapy in adult patients

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    Pawel Zwolak

    2013-11-01

    Full Text Available We present the results of the treatment of infected primary or delayed spine wounds after spinal surgery using negative pressure wound therapy. In our institution (University Hospital Zurich, Switzerland nine patients (three women and six men; mean age 68.6, range 43- 87 years were treated in the period between January to December 2011 for non-healing spinal wounds. The treatment consisted of repeated debridements, irrigation and temporary closure with negative pressure wound therapy system. Three patients were admitted with a spinal epidural abscess; two with osteoporotic lumbar fracture; two with pathologic vertebra fracture and spinal cord compression, and two with vertebra fracture after trauma. All nine patients have been treated with antibiotic therapy. In one case the hardware has been removed, in three patients laminectomy was performed without instrumentation, in five patients there was no need to remove the hardware. The average hospital stay was 16.6 days (range 11-30. The average follow-up was 3.8, range 0.5-14 months. The average number of negative pressure wound therapy procedures was three, with the range 1-11. Our retrospective study focuses on the clinical problems faced by the spinal surgeon, clinical outcomes after spinal surgery followed by wound infection, and negative pressure wound therapy. Moreover, we would like to emphasize the importance for the patients and their relatives to be fully informed about the increased complications of surgery and about the limitations of treatment of these wounds with negative pressure wound therapy.

  10. Comparison of compensatory reserve during lower-body negative pressure and hemorrhage in nonhuman primates

    Science.gov (United States)

    Howard, Jeffrey T.; Mulligan, Jane; Grudic, Greg Z.; Convertino, Victor A.

    2016-01-01

    Compensatory reserve was measured in baboons (n = 13) during hemorrhage (Hem) and lower-body negative pressure (LBNP) using a machine-learning algorithm developed to estimate compensatory reserve by detecting reductions in central blood volume during LBNP. The algorithm calculates compensatory reserve index (CRI) from normovolemia (CRI = 1) to cardiovascular decompensation (CRI = 0). The hypothesis was that Hem and LBNP will elicit similar CRI values and that CRI would have higher specificity than stroke volume (SV) in predicting decompensation. Blood was removed in four steps: 6.25%, 12.5%, 18.75%, and 25% of total blood volume. Four weeks after Hem, the same animals were subjected to four levels of LBNP that was matched on the basis of their central venous pressure. Data (mean ± 95% confidence interval) indicate that CRI decreased (P < 0.001) from baseline during Hem (0.69 ± 0.10, 0.57 ± 0.09, 0.36 ± 0.10, 0.16 ± 0.08, and 0.08 ± 0.03) and LBNP (0.76 ± 0.05, 0.66 ± 0.08, 0.36 ± 0.13, 0.23 ± 0.11, and 0.14 ± 0.09). CRI was not different between Hem and LBNP (P = 0.20). Linear regression analysis between Hem CRI and LBNP CRI revealed a slope of 1.03 and a correlation coefficient of 0.96. CRI exhibited greater specificity than SV in both Hem (92.3 vs. 82.1) and LBNP (94.8 vs. 83.1) and greater ROC AUC in Hem (0.94 vs. 0.84) and LBNP (0.94 vs. 0.92). These data support the hypothesis that Hem and LBNP elicited the same CRI response, suggesting that measurement of compensatory reserve is superior to SV as a predictor of cardiovascular decompensation PMID:27030667

  11. Coagulation changes during lower body negative pressure and blood loss in humans.

    Science.gov (United States)

    van Helmond, Noud; Johnson, Blair D; Curry, Timothy B; Cap, Andrew P; Convertino, Victor A; Joyner, Michael J

    2015-11-01

    We tested the hypothesis that markers of coagulation activation are greater during lower body negative pressure (LBNP) than those obtained during blood loss (BL). We assessed coagulation using both standard clinical tests and thrombelastography (TEG) in 12 men who performed a LBNP and BL protocol in a randomized order. LBNP consisted of 5-min stages at 0, -15, -30, and -45 mmHg of suction. BL included 5 min at baseline and following three stages of 333 ml of blood removal (up to 1,000 ml total). Arterial blood draws were performed at baseline and after the last stage of each protocol. We found that LBNP to -45 mmHg is a greater central hypovolemic stimulus versus BL; therefore, the coagulation markers were plotted against central venous pressure (CVP) to obtain stimulus-response relationships using the linear regression line slopes for both protocols. Paired t-tests were used to determine whether the slopes of these regression lines fell on similar trajectories for each protocol. Mean regression line slopes for coagulation markers versus CVP fell on similar trajectories during both protocols, except for TEG α° angle (-0.42 ± 0.96 during LBNP vs. -2.41 ± 1.13°/mmHg during BL; P coagulation was accelerated as evidenced by shortened R-times (LBNP, 9.9 ± 2.4 to 6.2 ± 1.1; BL, 8.7 ± 1.3 to 6.4 ± 0.4 min; both P coagulation markers observed during BL. Copyright © 2015 the American Physiological Society.

  12. Expiratory and expiratory plus inspiratory muscle training improves respiratory muscle strength in subjects with COPD: systematic review.

    Science.gov (United States)

    Neves, Leonardo F; Reis, Manoela H; Plentz, Rodrigo D M; Matte, Darlan L; Coronel, Christian C; Sbruzzi, Graciele

    2014-09-01

    Inspiratory muscle training (IMT) produces beneficial effects in COPD subjects, but the effects of expiratory muscle training (EMT) and EMT plus IMT in ventilatory training are still unclear. The aim of this study was to systematically review the effects of EMT and EMT plus IMT compared to control groups of COPD subjects. This study is a systematic review and meta-analysis. The search strategy included MEDLINE, Embase, LILACS, PEDro, and Cochrane CENTRAL and also manual search of references in published studies on the subject. Randomized trials comparing EMT and EMT plus IMT versus control groups of subjects with COPD were included. The outcomes analyzed were respiratory muscle strength and functional capacity. Two reviewers independently extracted the data. The search retrieved 609 articles. Five studies were included. We observed that EMT provided higher gain in maximum expiratory pressure (P(E(max)) 21.49 cm H2O, 95% CI 13.39-29.59) and maximum inspiratory pressure (P(I(max)) 7.68 cm H2O, 95% CI 0.90-14.45) compared to control groups. There was no significant difference in the 6-min walk test distance (29.01 m, 95% CI -39.62 to 97.65) and dyspnea (0.15, 95% CI -0.77 to 1.08). In relation to EMT plus IMT, we observed that P(E(max)) (31.98 cm H2O, 95% CI 26.93-37.03) and P(I(max)) (27.98 cm H2O, 95% CI 20.10-35.85) presented higher values compared to control groups. EMT and EMT plus IMT improve respiratory muscle strength and can be used as part of the treatment during pulmonary rehabilitation of subjects with severe to very severe COPD. Copyright © 2014 by Daedalus Enterprises.

  13. Levels of maximum end-expiratory carbon monoxide and certain cardiovascular parameters following hubble-bubble smoking.

    Science.gov (United States)

    Shafagoj, Yanal A; Mohammed, Faisal I

    2002-08-01

    The physiological effects of cigarette smoking have been widely studied, however, little is known regarding the effects of smoking hubble-bubble. We examined the acute effects of hubble-bubble smoking on heart rate, systolic, diastolic, and mean arterial blood pressure and maximum end-expiratory carbon monoxide. This study was carried out in the student laboratory, School of Medicine, Department of Physiology, University of Jordan, Amman, Jordan, during the summer of 1999. In 18 healthy habitual hubble-bubble smokers, heart rate, blood pressure, and maximum end-expiratory carbon monoxide was measured before, during and post smoking of one hubble-bubble run (45 minutes). Compared to base line (time zero), at the end of smoking heart rate, systolic blood pressure, diastolic blood pressure, mean arterial blood pressure, and maximum end-expiratory carbon monoxide were increased 16 2.4 beats per minute, 6.7 2.5 mm Hg, 4.4 1.6 mm Hg, 5.2 1.7 mm Hg, and 14.2 1.8 ppm, (mean standard error of mean, Phubble-bubble smoking elicits a modest increase in heart rate, systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and maximum end-expiratory carbon monoxide in healthy hubble-bubble smokers.

  14. Does negative-pressure wound therapy influence subjacent bacterial growth? A systematic review.

    Science.gov (United States)

    Glass, Graeme E; Murphy, George R F; Nanchahal, Jagdeep

    2017-08-01

    Negative-pressure wound therapy is a ubiquitous wound management resource. The influence of NPWT on the bacterial bioburden of the subjacent wound remains unclear. We sought to examine the evidence. MEDLINE, Embase, PubMed, the Cochrane Database of Systematic Reviews and the Cochrane Controlled Trials Register were searched for articles quantitatively evaluating bacterial load under NPWT. Twenty-four studies met the inclusion criteria including 4 randomised controlled trials, 8 clinical series and 12 experimental studies. Twenty studies evaluated conventional NPWT, while 4 evaluated infiltration-based NPWT. While 8 studies using conventional NPWT failed to demonstrate an observable effect on bacterial load, 7 studies reported that NPWT was inherently bacteriostatic and 5 others reported species selectivity with suppression of non-fermentative gram-negative bacilli (NFGNB), including Pseudomonas spp. Simultaneously, there was some evidence of enhanced proliferation of gram-positive cocci where the niche was cleared of NFGNB. Two of the 4 studies using infiltration-based NPWT also reported selectively impaired proliferation of Pseudomonas spp. The assumption that NPWT suppresses bacterial proliferation is oversimplified. There is evidence that NPWT exhibits species selectivity, suppressing the proliferation of NFGNB. However, this may depopulate the niche for exploitation by gram-positive cocci. This, in turn, has implications for the use of NPWT where highly virulent strains of gram-positive cocci have been isolated and the duration of NPWT therapy and frequency of dressing changes. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  15. Takotsubo cardiomyopathy precipitated by negative pressure pulmonary oedema following total thyroidectomy

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    K S Bharathi

    2016-01-01

    Full Text Available 'Takotsubo cardiomyopathy (TCM' or 'stress cardiomyopathy' is a reversible cardiomyopathy that is precipitated by intense emotional or physical stress. This syndrome is characterised by symptoms mimicking acute coronary syndrome with transient systolic dysfunction associated with regional wall motion abnormalities, which extend beyond a single coronary vascular bed in the absence of obstructive coronary vascular disease. The presentation of TCM and myocardial infarction is similar with sudden onset of chest pain, breathlessness as well as abnormalities in both the electrocardiogram and cardiac enzymes. It is difficult to differentiate between the two until cardiac catheterisation establishes the diagnosis. We report a case of TCM in a post-menopausal female, precipitated by negative pressure pulmonary oedema following total thyroidectomy in whom timely cardiac catheterisation established the diagnosis and influenced the management. Heightened awareness of this unique cardiomyopathy is essential to have a high index of suspicion in at-risk population for the prompt diagnosis of stress-related cardiomyopathy syndromes occurring in the perioperative period.

  16. Use of a risk assessment method to improve the safety of negative pressure wound therapy.

    Science.gov (United States)

    Lelong, Anne-Sophie; Martelli, Nicolas; Bonan, Brigitte; Prognon, Patrice; Pineau, Judith

    2014-06-01

    To conduct a risk analysis of the negative pressure wound therapy (NPWT) care process and to improve the safety of NPWT, a working group of nurses, hospital pharmacists, physicians and hospital managers performed a risk analysis for the process of NPWT care. The failure modes, effects and criticality analysis (FMECA) method was used for this analysis. Failure modes and their consequences were defined and classified as a function of their criticality to identify priority actions for improvement. By contrast to classical FMECA, the criticality index (CI) of each consequence was calculated by multiplying occurrence, severity and detection scores. We identified 13 failure modes, leading to 20 different consequences. The CI of consequences was initially 712, falling to 357 after corrective measures were implemented. The major improvements proposed included the establishment of 6-monthly training cycles for nurses, physicians and surgeons and the introduction of computerised prescription for NPWT. The FMECA method also made it possible to prioritise actions as a function of the criticality ranking of consequences and was easily understood and used by the working group. This study is, to our knowledge, the first to use the FMECA method to improve the safety of NPWT. © 2012 The Authors. International Wound Journal © 2012 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  17. Impact of negative affectivity and trait forgiveness on aortic blood pressure and coronary circulation.

    Science.gov (United States)

    Sanchez-Gonzalez, Marcos A; May, Ross W; Koutnik, Andrew P; Fincham, Frank D

    2015-02-01

    Prior research suggests that negative affectivity (NA) may have a direct adverse effect on coronary circulation, whereas forgiveness may provide cardioprotection. This study examined whether NA and forgiveness were independently related to aortic hemodynamics and the subendocardial viability index (SVI), a marker of coronary perfusion. A sample of 131 adults (M = 21.11 years, SD = 2.52) were evaluated for NA (depression, anxiety, and anger symptoms) and forgiveness (Tendency to Forgive Scale; TTF). Aortic hemodynamic parameters via applanation tonometry were assessed at rest and during sympathostimulation (cold pressor test; CPT). Hierarchical multiple regression analyses of resting values showed that NA was related to higher aortic blood pressure (ABP) and lower SVI. After controlling for demographics and for NA, TTF scores were significantly associated with decreased ABP, but increased SVI. CPT changes from baseline indicated that, after controlling for demographics and NA, TTF scores were significantly associated with SVI. Results indicate that NA significantly predicts ABP and decreased SVI. Conversely, forgiveness seems to provide cardioprotection by evoking decreased ABP while improving SVI. © 2014 Society for Psychophysiological Research.

  18. Bronchial fistula closure with negative pressure wound therapy: a feasible and cost-effective treatment.

    Science.gov (United States)

    Nunes, Rodrigo Barboza; Müller, Bruno Francisco; Cipriano, Federico Enrique Garcia; Coltro, Pedro Soler; Farina, Jayme Adriano

    2016-01-01

    Treatment of bronchial fistula (BF) after pulmonary lobectomy is a challenge. Often, patients require long hospital stay, have recurrent empyema and pneumonia, are susceptible to sepsis, often need broad-spectrum antibiotics, as well as various surgical approaches. With the advent and growing evidence of the benefits of negative pressure therapy (NPT), its use in some patients with BF has been reported with encouraging results concerning its feasibility and cost-effectiveness. The aim of this study was to demonstrate the application of NPT as a resource for BF treatment and comparatively analyze the overall cost of treatment. RESUMO O tratamento de fístula brônquica (FB) após lobectomia pulmonar é um desafio. Muitas vezes, o paciente demanda longo tempo de internação, apresenta recidivas de empiema e pneumonia, pode evoluir para sepse, frequentemente necessita de antibioticoterapia de amplo espectro, bem como de várias abordagens cirúrgicas. Com o advento e acúmulo de evidências dos benefícios da terapia por pressão negativa (TPN), seu uso em alguns pacientes com FB tem sido relatado com resultados animadores relativos à sua viabilidade e ao seu custo-efetividade. O objetivo deste estudo foi demonstrar a aplicação de TPN como recurso para tratamento da FB e analisar comparativamente o custo global do seu tratamento.

  19. The use of negative pressure wound therapy in the treatment of infected wounds. Case studies.

    Science.gov (United States)

    Jones, Daniel de Alcântara; Neves Filho, Wilson Vasconcelos; Guimarães, Janice de Souza; Castro, Daniel de Araújo; Ferracini, Antonio Marcos

    2016-01-01

    To evaluate the results and benefits obtained from the topical use of negative pressure wound therapy (NPWT) in patients with infected wounds. This was a retrospective study of 20 patients (17 males and three females, mean age 42 years) with infected wounds treated using NPWT. The infected wounds were caused by trauma. The treatment system used was VAC. ® (Vacuum Assisted Closure, KCI, San Antonio, United States) applied to the wound in continuous mode from 100 to 125 mmHg. The parameters related to the wounds (location, number of VAC changes, the size of the defects in the soft parts, and the evolution of the state of the wound), length of hospital stay, length of intravenous antibiotic therapy, and complications related to the use of this therapy were evaluated. The mean length of the hospital stay, use of NPWT, and antibacterial therapy were 41 days, 22.5 days, and 20 days respectively. The use of the VAC led to a mean reduction of 29% in the wound area (95.65-68.1 cm 2 ; p  wound with complete eradication of the infection. No complication directly caused by NPWT was observed. NPWT stimulates infection-free scar tissue formation in a short time, and is a quick and comfortable alternative to conventional infected wounds treatment methods.

  20. Negative-Pressure Wound Therapy for Ludwig’s Angina: A Case Series

    Directory of Open Access Journals (Sweden)

    Nainika Nanda, BA

    2017-11-01

    Full Text Available Summary:. Negative-pressure wound therapy (NPWT is a well-established therapeutic approach for various complex wound classes. There is currently limited information on the use of NPWT for the scope of head and neck wounds. However, NPWT has been used successfully in some cases, including malignancy, infection, and trauma. In West Virginia, the incidence of dental-related infections leading to Ludwig’s Angina is high due to lack of access to dental care. Our case series describes the application of vacuum-based therapy in conjunction with antibiotic therapy for quick, effective closure of deep tissue infections before definitive complex wound repair via graft and flap reconstructions. Over a period of 3 months, 2 patients with submental infections extending to the lateral neck demonstrated clean, efficient wound closure with NPWT for less than 14 days while hospitalized at West Virginia University Medicine. Outpatient follow-up with these patients demonstrated excellent cosmetic outcomes with minimal contracture or hypertrophy of healing tissue. NPWT promotes wound healing through decreased edema, improved perfusion, and increased granulation of tissue based on our findings. Our series encourages the use of NPWT for initial closure of complex wounds secondary to deep neck infections.

  1. The use of negative pressure wound therapy in the treatment of infected wounds. Case studies

    Directory of Open Access Journals (Sweden)

    Daniel de Alcântara Jones

    Full Text Available ABSTRACT OBJECTIVE: To evaluate the results and benefits obtained from the topical use of negative pressure wound therapy (NPWT in patients with infected wounds. METHODS: This was a retrospective study of 20 patients (17 males and three females, mean age 42 years with infected wounds treated using NPWT. The infected wounds were caused by trauma. The treatment system used was VAC.(r (Vacuum Assisted Closure, KCI, San Antonio, United States applied to the wound in continuous mode from 100 to 125 mmHg. The parameters related to the wounds (location, number of VAC changes, the size of the defects in the soft parts, and the evolution of the state of the wound, length of hospital stay, length of intravenous antibiotic therapy, and complications related to the use of this therapy were evaluated. RESULTS: The mean length of the hospital stay, use of NPWT, and antibacterial therapy were 41 days, 22.5 days, and 20 days respectively. The use of the VAC led to a mean reduction of 29% in the wound area (95.65-68.1 cm2; p < 0.05. Only one patient did not show any improvement in the final appearance of the wound with complete eradication of the infection. No complication directly caused by NPWT was observed. CONCLUSION: NPWT stimulates infection-free scar tissue formation in a short time, and is a quick and comfortable alternative to conventional infected wounds treatment methods.

  2. Randomized clinical trial to compare negative-pressure wound therapy approaches with low and high pressure, silicone-coated dressing, and polyurethane foam dressing.

    Science.gov (United States)

    Lavery, Lawrence A; La Fontaine, Javier; Thakral, Gaurav; Kim, Paul J; Bhavan, Kavita; Davis, Kathryn E

    2014-03-01

    This study was designed to compare two approaches to negative-pressure wound therapy: 125-mmHg pressure with a polyurethane foam dressing and 75-mmHg pressure with a silicone-coated dressing. Forty patients with diabetic foot wounds, after incision and drainage or amputation for infection, were assigned randomly to negative-pressure wound therapy with 75-mmHg continuous pressure with a silicone-covered dressing (75-mmHg group) or 125-mmHg with a polyurethane foam dressing (125-mmHg group) for up to 4 weeks or until surgical closure. There was no difference in the proportion of wounds that were closed surgically (75-mmHg group, 50 percent; 125-mmHg group, 60 percent), wounds that demonstrated 50 percent wound area reduction (75-mmHg group, 65 percent; 125-mmHg group, 80 percent), or wounds that demonstrated 50 percent wound volume reduction after 4 weeks of therapy (75-mmHg group, 95 percent; 125-mmHg group, 90 percent). The authors' results suggest that there was no difference in outcomes in wounds treated with low pressure (75 mmHg) with a silicone-coated interface and high pressure (125 mmHg) with a polyurethane foam interface. Therapeutic, II.

  3. Patients experiences of negative pressure wound therapy at home for the treatment of deep perivascular groin infection after vascular surgery.

    Science.gov (United States)

    Monsen, Christina; Acosta, Stefan; Kumlien, Christine

    2017-05-01

    To explore experiences of negative pressure wound therapy at home, in patients with deep perivascular groin infection after vascular surgery and management in daily life. Deep surgical site infection after vascular surgery with exposed vessels often requires long-term treatment with negative pressure wound therapy, and continued therapy at home has become routine. An explorative qualitative study. Nine men and six women with a deep surgical site infection in the groin after vascular surgery, treated in their home with negative pressure wound therapy, were interviewed. The interviews were analysed using manifest and latent content analysis. Undergoing negative pressure wound therapy at home meant a transition from being a dependent patient to a person who must have self-care competence and be involved in their own care. A need to feel prepared for this before discharge from hospital was expressed. Lack of information and feelings of uncertainty prolonged the time before feeling confident in managing the treatment. The informants gradually accepted the need to be tied up to a machine, became competent in its management and found solutions to perform everyday tasks. Overall, it was a relief to be treated at home. Several benefits of negative pressure wound therapy at home were expressed. However, unnecessary stress and anxiety were experienced due to a lack of information on the treatment and instruction concerning the equipment. Adequate information and education must therefore be provided to facilitate the transition from a patient to a person with self-care competence and ability to manage this treatment at home. The findings revealed a need for more support and knowledge in their transition from hospital care to home care with negative pressure wound therapy. Routines must be established that ensure patient safety and security in treatment at home. © 2016 John Wiley & Sons Ltd.

  4. Relaxation effects in ionic mobility and cluster formation: negative ions in SF{sub 6} at high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Juarez, A M; De Urquijo, J; Hinojosa, G [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, PO Box 48-3, 62251, Cuernavaca, Mor. (Mexico); Hernandez-Avila, J L [Departamento de Energia, Universidad Autonoma Metropolitana, Av. San Pablo 180, 02200 Mexico, D.F. (Mexico); Basurto, E, E-mail: juarez@fis.unam.m [Departamento de Ciencias Basicas, Universidad Autonoma Metropolitana, Av. San Pablo 180, 02200 Mexico, D.F. (Mexico)

    2010-06-15

    The relaxation effects of the ionic mobility and the formation of negative-ion clusters in SF{sub 6} are studied in this work. For this purpose, we have measured the mobility of negative ions in SF{sub 6} over the pressure range 100-800 Torr at a fixed value of density-normalized electric field, E/N, of 20 Td (1 Townsend = 10{sup -17} V cm{sup 2}). The data obtained show a clear dependence of the negative-ion drift velocity on drift distance. It is observed that the drift velocity (mobility) reaches a steady-state value only for drift distances above 2 cm, over the studied pressure range. In addition to this, we have observed that the ionic mobility depends strongly on the gas pressure. An explanation of this dependence of the ionic mobility on gas pressure is given in terms of a negative-ion clustering formation process. It was found that the assumption of a linear dependence of the cluster ion mass on pressure provides a satisfactory explanation for the observed mobilities.

  5. Role of bronchodilation and pattern of breathing in increasing tidal expiratory flow with progressive induced hypercapnia in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Finucane, Kevin E; Singh, Bhajan

    2018-01-01

    Hypercapnia (HC) in vitro relaxes airway smooth muscle; in vivo, it increases respiratory effort, tidal expiratory flows (V̇ exp ), and, by decreasing inspiratory duration (Ti), increases elastic recoil pressure (Pel) via lung viscoelasticity; however, its effect on airway resistance is uncertain. We examined the contributions of bronchodilation, Ti, and expiratory effort to increasing V̇ exp with progressive HC in 10 subjects with chronic obstructive pulmonary disease (COPD): mean forced expiratory volume in 1 s (FEV 1 ) 53% predicted. Lung volumes (Vl), V̇ exp , esophageal pressure (Pes), Ti, and end-tidal Pco 2 ([Formula: see text]) were measured during six tidal breaths followed by an inspiratory capacity (IC), breathing air, and at three levels of HC. V̇ exp and V̇ with submaximal forced vital capacities breathing air (V̇ sFVC ) were compared. Pulmonary resistance ( Rl) was measured from the Pes-V̇ relationship. V̇ exp and Pes at end-expiratory lung volume (EELV) + 0.3 tidal volume [V̇ (0.3Vt) and Pes (0.3Vt) , respectively], Ti, and Rl correlated with [Formula: see text] ( P tidal expiratory flows by inducing bronchodilation and via an increased rate of inspiration and lung viscoelasticity, a probable increase in lung elastic recoil pressure, both changes increasing expiratory flows, promoting lung emptying and a stable end-expiratory volume. Bronchodilation with HC occurred despite optimal standard bronchodilator therapy, suggesting that in COPD further bronchodilation is possible.

  6. Frequency pressure transducer with a sensitivity of mem capacitor on the basis of transistor structure with negative resistance

    Science.gov (United States)

    Osadchuk, Oleksandr V.; Osadchuk, Iaroslav O.; Suleimenov, Batyrbek; Zyska, Tomasz; Arman, Abenov; Tleshova, Akmaral; GrÄ dz, Å.»aklin

    2017-08-01

    In the article the pressure transducer with frequency output based on the structure of the bipolar-field transistors with negative resistance and tenso sensitive MEMS capacitor has been considered. A mathematical model of the frequency pressure transducer in dynamic regime has been developed that allowed to determine the voltage or current in the circuit at any given moment in time when acting this pressure. Analytical expressions of the conversion function and sensitivity equation has been received. The sensitivity of the developed device is between 0,95kHz/kPa to 1,65kHz/kPa.

  7. Cost-utility analysis of negative pressure wound therapy in high-risk cesarean section wounds.

    Science.gov (United States)

    Tuffaha, Haitham W; Gillespie, Brigid M; Chaboyer, Wendy; Gordon, Louisa G; Scuffham, Paul A

    2015-05-15

    Obese women undergoing cesarean section are at increased risk of postoperative infection. There is growing interest in negative pressure wound therapy (NPWT) to prevent closed surgical incision complications including surgical site infection; however, the evidence on the effectiveness and cost-effectiveness of this technology is limited. The objective of this study was to evaluate the cost-effectiveness of NPWT compared with that of standard dressing in preventing surgical site infection in obese women undergoing elective cesarean section based on current evidence and to estimate the value and optimal design of additional research to study this technology. The analysis was from the perspective of Queensland Health, Australia, using a decision model. Parameters were obtained from the published literature, a pilot clinical trial, and expert opinion. Monte Carlo simulation was performed to calculate the net monetary benefit, characterize decision uncertainty, and estimate the value of additional research. Comparing the expected monetary benefits and costs of alternative trial sample sizes informed the optimal future study design. The incremental net monetary benefit of NPWT was Australian dollars 70, indicating that NPWT is cost-effective compared with that of standard dressing. The probability of NPWT being cost-effective was 65%. The estimated value of additional research to resolve decision uncertainty would be Australian dollars 2.7 million. The optimal sample size of a future trial investigating the relative effectiveness of NPWT would be 200 patients per arm. Based on the current evidence, NPWT is cost-effective; however, there is high uncertainty surrounding the decision to adopt this technology. Additional research is worthwhile before implementation. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Clinical Features of Patients with Diffuse Alveolar Hemorrhage due to Negative-Pressure Pulmonary Edema.

    Science.gov (United States)

    Contou, Damien; Voiriot, Guillaume; Djibré, Michel; Labbé, Vincent; Fartoukh, Muriel; Parrot, Antoine

    2017-08-01

    Diffuse alveolar hemorrhage (DAH) with negative-pressure pulmonary edema (NPPE) is an uncommon yet life-threatening condition. We aimed at describing the circumstances, clinical, radiological, and bronchoscopic features, as well as the outcome of patients with NPPE-related DAH. We performed a retrospective, observational cohort study, using data prospectively collected over 35 years in an intensive care unit (ICU). Of the 149 patients admitted for DAH, we identified 18 NPPE episodes in 15 patients, one admitted four times for recurrent NPPE-related DAH. The patients were primarily young, male, and athletic. The NPPE setting was postoperative (n = 12/18, 67%) or following generalized tonic-clonic seizures (n = 6/18, 33%). Hemoptysis was almost constant (n = 17/18, 94%), yet rarely massive (>200 cc, n = 1/18, 6%), with anemia observed in 10 (56%) episodes. The DAH triad (hemoptysis, anemia, and pulmonary infiltrates) was observed in 50% of episodes (n = 9/18), and acute respiratory failure in 94% (n = 17/18). Chest computed tomography revealed diffuse bilateral ground glass opacities (n = 10/10, 100%), while bronchoscopy detected bilateral hemorrhage (n = 12/12, 100%) and macroscopically bloody bronchoalveolar lavage, with siderophage absence in most (n = 7/8, 88%), indicating acute DAH. While one episode proved fatal, the other 17 recovered rapidly, with a mean ICU stay lasting 4.6 (2-15) days. Typically, the evolution was rapidly favorable under supportive care. NPPE-related DAH is a rare life-threatening condition occurring primarily after tonic-clonic generalized seizure or generalized anesthesia. Clinical circumstances are a key to its diagnosis. Early diagnosis and recognition likely allow for successful management of this potentially serious complication, whereas ictal-DAH appears ominous in epileptic patients.

  9. Negative pressure wound therapy after partial diabetic foot amputation: a multicentre, randomised controlled trial.

    Science.gov (United States)

    Armstrong, David G; Lavery, Lawrence A

    2005-11-12

    Diabetic foot wounds, particularly those secondary to amputation, are very complex and difficult to treat. We investigated whether negative pressure wound therapy (NPWT) improves the proportion and rate of wound healing after partial foot amputation in patients with diabetes. We enrolled 162 patients into a 16-week, 18-centre, randomised clinical trial in the USA. Inclusion criteria consisted of partial foot amputation wounds up to the transmetatarsal level and evidence of adequate perfusion. Patients who were randomly assigned to NPWT (n=77) received treatment with dressing changes every 48 h. Control patients (n=85) received standard moist wound care according to consensus guidelines. NPWT was delivered through the Vacuum Assisted Closure (VAC) Therapy System. Wounds were treated until healing or completion of the 112-day period of active treatment. Analysis was by intention to treat. This study has been registered with , number NCT00224796. More patients healed in the NPWT group than in the control group (43 [56%] vs 33 [39%], p=0.040). The rate of wound healing, based on the time to complete closure, was faster in the NPWT group than in controls (p=0.005). The rate of granulation tissue formation, based on the time to 76-100% formation in the wound bed, was faster in the NPWT group than in controls (p=0.002). The frequency and severity of adverse events (of which the most common was wound infection) were similar in both treatment groups. NPWT delivered by the VAC Therapy System seems to be a safe and effective treatment for complex diabetic foot wounds, and could lead to a higher proportion of healed wounds, faster healing rates, and potentially fewer re-amputations than standard care.

  10. A prospective randomized evaluation of negative-pressure wound dressings for diabetic foot wounds.

    Science.gov (United States)

    Eginton, Mark T; Brown, Kellie R; Seabrook, Gary R; Towne, Jonathan B; Cambria, Robert A

    2003-11-01

    Optimal treatment for large diabetic foot wounds is ill defined. The purpose of this study was to compare the rate of wound healing with the Vacuum Assisted Closure device trade mark (VAC) to conventional moist dressings in the treatment of large diabetic foot wounds. Diabetics with significant soft tissue defects of the foot were considered for enrollment. Patients were randomized to receive either moist gauze dressings or VAC treatments for 2 weeks, after which they were treated with the alternative dressing for an additional 2 weeks. Wounds were photographed weekly and wound dimensions calculated in a blinded fashion with spatial analysis software. Percent change in wound dimensions were calculated and compared for each weekly assessment and over 2 weeks of therapy with each dressing type. Ten patients were enrolled in the trial, but two were lost to follow-up and two were withdrawn. Complete data were available for analysis on seven wounds in six patients. Average length, width, and depth of the wounds at initiation of the trial was 7.7, 3.5, and 3.1 cm, respectively. Only the wound depth was significantly decreased over the weeks of the trial to 1.2 cm ( p VAC dressings decreased the wound volume and depth significantly more than moist gauze dressings (59% vs. 0% and 49% vs. 8%, respectively). VAC dressings were associated with a decrease in all wound dimensions while wound length and width increased with moist dressings. In summary, over the first several weeks of therapy, VAC dressings decreased wound depth and volume more effectively than moist gauze dressings. Negative-pressure wound treatment may accelerate closure of large foot wounds in the diabetic patient.

  11. Loss of protein, immunoglobulins, and electrolytes in exudates from negative pressure wound therapy.

    Science.gov (United States)

    Hourigan, Leslie A; Hourigan, Leslie; Linfoot, John A; Linfoot, John; Chung, Kevin K; Chung, Kevin; Dubick, Michael A; Dubick, Michael; Rivera, Rachael L; Rivera, Racheal; Jones, John A; Salinas, Reuben D; Salinas, Reuben; Mann, Elizabeth A; Wade, Charles E; Wade, Charles; Wolf, Steven E; Baskin, Toney W; Baskin, Toney

    2010-10-01

    A relatively new technology in wound care, negative pressure wound therapy (NPWT), has become widely used for the management of open abdomens and soft tissue wounds and provides a means to collect wound exudate to quantify protein loss. A prospective observational study was conducted in surgical, trauma, or burn patients (8 patients with open abdomens and 9 patients with acute soft tissue wounds on NPWT). NPWT exudate was collected and assayed to characterize loss of protein, electrolyte, and immunoglobulins over multiple days of NPWT. Total protein was present in open abdomen NPWT exudate, 2.9 ± 0.9 g/dL. In the soft tissue wound exudate, a similar mean concentration was found, 2.59 ± 0.6 g/dL (P = .34). Exudate concentrations of albumin, urea nitrogen, immunoglobulins, and electrolytes between wound types were also not significantly different. There were significant (P = .03) differences in the median volume of exudate, 1031 mL/d for open abdomens in contrast to 245 mL/d soft tissue wounds. Therefore, 24-hour losses of proteins and electrolytes were greater in patients with open abdomens than soft tissue wounds. Mean total protein loss was 25 ± 17 g/d for open abdomens and 8 ± 5 g/d for soft tissue wounds. There are significant losses of proteins in wound exudate. As there is no significant difference in the concentration of total protein between wound type, the rate of loss may be calculated as 2.9 g/dL times the volume of wound exudate. The rate of protein loss from wounds is similar to the presently assumed insensible loss rate of 12-25 g/d.

  12. Suture Technique to Prevent Air Leakage during Negative-Pressure Wound Therapy in Fournier Gangrene.

    Science.gov (United States)

    Chang, Feng-Shu; Chou, Chieh; Hu, Chuan-Yu; Huang, Shu-Hung

    2018-01-01

    The use of negative-pressure wound therapy (NPWT) for Fournier gangrene management is well documented; however, it is difficult to fixate GranuFoam dressings and maintain an airtight seal over the perineum area. We developed a simple method to facilitate GranuFoam fixation and improve airtight sealing. The Fournier's gangrene severity index (FGSI) score less than 9 was collected in from January 2015 to October 2016. All 13 patients underwent fasciotomy, and NPWT was applied directly on fasciotomy wounds after the debridement of infected tissue. Partial wound closure was performed, and a portion of GranuFoam was inserted to facilitate fixation. The seal check was converted to a 0-10 scale score that was recorded every 4 hours during NPWT. Patient profiles including medical history, FGSI, method of wound closure, and length of stay were collected in this study. The median age of the patients was 62 (38-76) years. The mean FGSI score was 4.3 ± 3.1. The average duration of NPWT was 17.5 ± 11.5 days, and the average seal check score was 0.8 ± 0.5. No seal check alarms were noted during the study. Successful wound closure was achieved in all patients without using additional reconstruction methods such as skin grafting or muscle flap coverage. The present results suggest that partial wound-edge closure and in situ GranuFoam fixation improve the NPWT leaks in Fournier gangrene wounds. Furthermore, this method is simple to learn and can be useful in applying NPWT to anatomically difficult areas.

  13. Efeitos da manobra de hiperinsuflação manual associada à pressão positiva expiratória final em pacientes submetidos à cirurgia de revascularização miocárdica Effects of manual hyperinflation maneuver associated with positive end expiratory pressure in patients within coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Laura Jurema dos Santos

    2010-03-01

    Full Text Available OBJETIVO: Verificar os efeitos da manobra de hiperinsuflação manual associada à pressão positiva expiratória final em pacientes submetidos à cirurgia de revascularização do miocárdio. MÉTODOS: Ensaio clínico randomizado realizado entre agosto de 2007 e julho de 2008 na unidade de terapia intensiva do Hospital Luterano (ULBRA. Os pacientes foram divididos em grupo intervenção, no qual foi aplicada a manobra de hiperinsuflação manual associada à pressão positiva expiratória final, e grupo controle. As variáveis ventilatórias foram mensuradas em dois momentos: pré-manobra e pós-manobra. Foram utilizados os testes t de Student para amostras independentes e pareadas, bem como os testes exato de Fisher e o qui-quadrado de McNemar. RESULTADOS: Foram incluídos 18 pacientes durante o período de estudo, com idade média de 64±11 anos, sendo que houve predomínio do sexo feminino (55,6%. O volume corrente inspirado foi de 594± 112 ml no grupo intervenção e 487± 51 ml no grupo controle (p=0,024 e o volume corrente expirado de 598± 105 ml no grupo intervenção e 490± 58 ml no grupo controle (p=0,02. A média da complacência pulmonar estática no grupo intervenção pré-manobra foi de 41,6± 12,1 ml/cmH2O e pós-manobra de 47,4± 16,6 ml/cmH2O (p=0,03. Não houve diferença significativa entre os grupos nas seguintes variáveis: saturação periférica de oxigênio, pressão arterial de oxigênio, tempo de extubação e alterações radiológicas. CONCLUSÃO: Os resultados demonstram uma tendência da manobra de hiperinsuflação manual associada à pressão positiva expiratória final promover aumento dos volumes pulmonares e da complacência estática, entretanto estes achados necessitam confirmação.OBJECTIVE: To verify the effects of manual hyperinflation maneuver associated with positive end expiratory pressure in coronary artery bypass grafting patients. METHODS: This was a randomized trial, conducted from August 2007

  14. Expiratory muscle control during vomiting - Role of brain stem expiratory neurons

    Science.gov (United States)

    Miller, A. D.; Tan, L. K.

    1987-01-01

    The neural mechanisms controlling the muscles involved during vomiting were examined using decerebrated cats. In one experiment, the activity of the ventral respiratory group (VRG) expiratory (E) neurons was recorded during induced 'fictive vomiting' (i.e., a series of bursts of coactivation of abdominal and phrenic nerves that would be expected to produce expulsion in unparalyzed animals) and vomiting. In a second, abdominal muscle electromyographic and nerve activity were compared before and after sectioning the axons of descending VRG E neurons as they cross the midline between C1 and the obex (the procedure that is known to abolish expiratory modulation of internal intercostal muscle activity). The results of the study indicate that the abdominal muscles are controlled differently during respiration and vomiting.

  15. Efeitos da pressão positiva expiratória nas vias aéreas sobre a atividade eletromiográfica da musculatura acessória da inspiração em portadores de DPOC Effects of expiratory positive airway pressure on the electromyographic activity of accessory inspiratory muscles in COPD patients

    Directory of Open Access Journals (Sweden)

    Dannuey Machado Cardoso

    2011-02-01

    Full Text Available OBJETIVO: Avaliar a atividade eletromiográfica (AE dos músculos esternocleidomastoideo (ECM e escaleno durante e após a aplicação de expiratory positive airway pressure (EPAP, pressão positiva expiratória nas vias aéreas em portadores de DPOC. MÉTODOS: Ensaio clínico simples cego com 13 indivíduos hígidos como controles e 12 pacientes com DPOC estável. No momento basal, foram determinados a AE em respiração espontânea, parâmetros da função pulmonar e a força muscular respiratória. Posteriormente, foi aplicada EPAP de 15 cmH2O com uma máscara facial durante 25 min, com o registro do sinal eletromiográfico dos músculos ECM e escaleno a cada 5 min. Um último registro foi obtido 10 min após a retirada da máscara. RESULTADOS: Observamos que o comportamento da AE dos músculos ECM e escaleno foi semelhante nos controles e pacientes com DPOC (p = 0,716 e p = 0,789, respectivamente. Porém, ao longo da aplicação de EPAP, ambos os músculos mostraram uma tendência ao aumento da AE. Além disso, houve uma redução significativa da AE do ECM entre o momento final e basal (p = 0,034. CONCLUSÕES: A aplicação de EPAP promoveu uma redução significativa da AE do músculo ECM tanto nos controles quanto nos portadores de DPOC estável. Porém, isso não ocorreu em relação à AE do músculo escaleno.OBJECTIVE: To evaluate the electromyographic activity (EA of sternocleidomastoid (SCM and scalene muscles during and after the use of expiratory positive airway pressure (EPAP in patients with COPD. METHODS: This was a clinical single-blind trial involving 13 healthy subjects as controls and 12 patients with stable COPD. At baseline, we determined EA during spontaneous respiration, lung function parameters, and respiratory muscle strength. Subsequently, EPAP at 15 cmH2O was applied by means of a face mask for 25 min, during which the EA of the SCM and scalene muscles was recorded every 5 min. A final record was obtained 10 min

  16. Evaluation of a Decision-Making Curriculum for Teaching Adolescents with Disabilities to Resist Negative Peer Pressure

    Science.gov (United States)

    Khemka, Ishita; Hickson, Linda; Mallory, Sarah B.

    2016-01-01

    This study was designed to assess the impact of a decision-making curriculum (PEER-DM) on the social peer relationship knowledge and self-protective decision-making skills of adolescents with disabilities in hypothetical situations involving negative peer pressure. A randomized design was used to assign students with disabilities from…

  17. Major bleeding during negative pressure wound/VAC (R) - therapy for postsurgical deep sternal wound infection - a critical appraisal

    NARCIS (Netherlands)

    van Wingerden, J.J.; Segers, P.; Jekel, L.

    2011-01-01

    Negative-pressure wound therapy, commercially known as vacuum-assisted closure (V.A.C.(R)) therapy, has become one of the most popular (and efficacious) interim (prior to flap reconstruction) or definite methods of managing deep sternal wound infection. Complications such as profuse bleeding, which

  18. Peak Expiratory Flow Rate In Cigarette Smokers | Ukoli | Highland ...

    African Journals Online (AJOL)

    Objective: To compare lung function between smokers and non-smokers using Peak Expiratory Flow Rate (PEFR). Methods: This study examines the peak expiratory flow rate (PEFR) of three hundred and forty cigarette smokers, age and sex-matched with PEFR of equal number of non-smokers. Results: The mean PEFR of ...

  19. Changes in Peak Expiratory Flow Rate, Blood Pressure

    African Journals Online (AJOL)

    FinePrint

    2010-03-23

    Mar 23, 2010 ... There are many compounds in coffee that are often thought to have implications upon human health; these include. Caffeine, Micronutrients, LDL. Cholesterols and Chlorogenic acid. The major physiologically active substance in coffee is the alkaloid caffeine. (C H O N .H O), also called guaranine or. 8. 10.

  20. Incisional negative pressure therapy to prevent wound complications following cesarean section in morbidly obese women: a pilot study.

    Science.gov (United States)

    Mark, Katrina S; Alger, Lindsay; Terplan, Mishka

    2014-08-01

    We sought to evaluate the efficacy of incisional negative pressure therapy in decreasing postoperative wound complications when placed prophylactically over clean, closed incisions following cesarean section in obese patients. This was a retrospective cohort study comparing rates of wound complications following cesarean sections in morbidly obese women prior to and following the institution of standard use of prophylactic incisional negative pressure therapy. All women with a body mass index greater than 45 kg/m(2) undergoing cesarean section in a 2-year period in a single institution were included. The exposure was incisional negative pressure therapy, which began in September 2009, versus standard wound dressing used in the previous year. The main outcome was wound complication identified by ICD-9 codes. Demographic and wound outcomes were compared with χ(2) and t tests. Stata version 11.0 was used for all analysis. A total of 63 women met the inclusion criteria, 21 of whom received negative pressure wound therapy. The historical comparison and exposure groups were similar in all characteristics studied with the exceptions of length of surgery (64 vs 76 minutes, P = .03), length of labor (78 vs 261 minutes, P = .02), scheduled versus nonscheduled (77% vs 52%, P = .04), and mean age (29.5 vs 26.1 years, P = .04), respectively. There were 5 wound complications in the control group (10.4%) and none (0%) in the study group (P = .15). This pilot study suggests a decrease in wound complications in morbidly obese women receiving incisional negative pressure therapy following cesarean section. © The Author(s) 2013.

  1. The partitioning of nanoparticles to endothelium or interstitium during ultrasound-microbubble-targeted delivery depends on peak-negative pressure

    Energy Technology Data Exchange (ETDEWEB)

    Hsiang, Y.-H.; Song, J.; Price, R. J., E-mail: rprice@virginia.edu [University of Virginia, Department of Biomedical Engineering (United States)

    2015-08-15

    Patients diagnosed with advanced peripheral arterial disease often face poor prognoses and have limited treatment options. For some patient populations, the therapeutic growth of collateral arteries (i.e. arteriogenesis) that bypass regions affected by vascular disease may become a viable treatment option. Our group and others are developing therapeutic approaches centered on the ability of ultrasound-activated microbubbles to permeabilize skeletal muscle capillaries and facilitate the targeted delivery of pro-arteriogenic growth factor-bearing nanoparticles. The development of such approaches would benefit significantly from a better understanding of how nanoparticle diameter and ultrasound peak-negative pressure affect both total nanoparticle delivery and the partitioning of nanoparticles to endothelial or interstitial compartments. Toward this goal, using Balb/C mice that had undergone unilateral femoral artery ligation, we intra-arterially co-injected nanoparticles (50 and 100 nm) with microbubbles, applied 1 MHz ultrasound to the gracilis adductor muscle at peak-negative pressures of 0.7, 0.55, 0.4, and 0.2 MPa, and analyzed nanoparticle delivery and distribution. As expected, total nanoparticle (50 and 100 nm) delivery increased with increasing peak-negative pressure, with 50 nm nanoparticles exhibiting greater tissue coverage than 100 nm nanoparticles. Of particular interest, increasing peak-negative pressure resulted in increased delivery to the interstitium for both nanoparticle sizes, but had little influence on nanoparticle delivery to the endothelium. Thus, we conclude that alterations to peak-negative pressure may be used to adjust the fraction of nanoparticles delivered to the interstitial compartment. This information will be useful when designing ultrasound protocols for delivering pro-arteriogenic nanoparticles to skeletal muscle.

  2. The partitioning of nanoparticles to endothelium or interstitium during ultrasound-microbubble-targeted delivery depends on peak-negative pressure

    International Nuclear Information System (INIS)

    Hsiang, Y.-H.; Song, J.; Price, R. J.

    2015-01-01

    Patients diagnosed with advanced peripheral arterial disease often face poor prognoses and have limited treatment options. For some patient populations, the therapeutic growth of collateral arteries (i.e. arteriogenesis) that bypass regions affected by vascular disease may become a viable treatment option. Our group and others are developing therapeutic approaches centered on the ability of ultrasound-activated microbubbles to permeabilize skeletal muscle capillaries and facilitate the targeted delivery of pro-arteriogenic growth factor-bearing nanoparticles. The development of such approaches would benefit significantly from a better understanding of how nanoparticle diameter and ultrasound peak-negative pressure affect both total nanoparticle delivery and the partitioning of nanoparticles to endothelial or interstitial compartments. Toward this goal, using Balb/C mice that had undergone unilateral femoral artery ligation, we intra-arterially co-injected nanoparticles (50 and 100 nm) with microbubbles, applied 1 MHz ultrasound to the gracilis adductor muscle at peak-negative pressures of 0.7, 0.55, 0.4, and 0.2 MPa, and analyzed nanoparticle delivery and distribution. As expected, total nanoparticle (50 and 100 nm) delivery increased with increasing peak-negative pressure, with 50 nm nanoparticles exhibiting greater tissue coverage than 100 nm nanoparticles. Of particular interest, increasing peak-negative pressure resulted in increased delivery to the interstitium for both nanoparticle sizes, but had little influence on nanoparticle delivery to the endothelium. Thus, we conclude that alterations to peak-negative pressure may be used to adjust the fraction of nanoparticles delivered to the interstitial compartment. This information will be useful when designing ultrasound protocols for delivering pro-arteriogenic nanoparticles to skeletal muscle

  3. Pressure transduction and fluid evacuation during conventional negative pressure wound therapy of the open abdomen and NPWT using a protective disc over the intestines

    Directory of Open Access Journals (Sweden)

    Lindstedt Sandra

    2012-03-01

    Full Text Available Abstract Background Negative pressure wound therapy (NPWT has gained acceptance among surgeons, for the treatment of open abdomen, since very high closure rates have been reported with this method, compared to other kinds of wound management for the open abdomen. However, the method has occasionally been associated with increased development of fistulae. We have previously shown that NPWT induces ischemia in the underlying small intestines close to the vacuum source, and that a protective disc placed between the intestines and the vacuum source prevents the induction of ischemia. In this study we compare pressure transduction and fluid evacuation of the open abdomen with conventional NPWT and NPWT with a protective disc. Methods Six pigs underwent midline incision and the application of conventional NPWT and NPWT with a protective disc between the intestines and the vacuum source. The pressure transduction was measured centrally beneath the dressing, and at the anterior abdominal wall, before and after the application of topical negative pressures of -50, -70 and -120 mmHg. The drainage of fluid from the abdomen was measured, with and without the protective disc. Results Abdominal drainage was significantly better (p Conclusions The drainage of the open abdomen was significantly more effective when using NWPT with the protective disc than with conventional NWPT. This is believed to be due to the more even and effective pressure transduction in the open abdomen using a protective disc in combination with NPWT.

  4. Pressão expiratória positiva na via aérea por máscara facial na hemodinâmica de pós-operatórios cardíacos Expiratory positive airway pressure in postoperative cardiac hemodynamics

    Directory of Open Access Journals (Sweden)

    Ana Claudia Borges dos Santos Sena

    2010-10-01

    Full Text Available FUNDAMENTOS: A pressão expiratória positiva na via aérea por máscara facial (EPAP é utilizada no pós-operatório de cirurgias cardíacas, entretanto, seus efeitos hemodinâmicos não foram claramente estudados. OBJETIVO: Avaliar as alterações hemodinâmicas causadas pela EPAP em pacientes pós-cirurgia cardíaca monitorados por cateter de Swan-Ganz. MÉTODOS: Foram incluídos no estudo, pacientes no primeiro ou segundo pós-operatório de cirurgia cardíaca, estáveis hemodinamicamente e com cateter de Swan-Ganz. Eles foram avaliados em repouso e após o uso de 10 cmH2O de EPAP, de forma randomizada. As variáveis estudadas foram: saturação de oxigênio, frequências cardíaca e respiratória, pressões arteriais médias sistêmica e pulmonar (PAM e PAMP, pressões venosa central (PVC e de oclusão da atéria pulmonar (POAP, débito e índice cardíacos, e resistências vasculares sistêmica e pulmonar. Os pacientes foram divididos em subgrupos (com fração de ejeção 50% e os dados foram comparados por teste t e ANOVA. RESULTADOS: Vinte e oito pacientes foram estudados (22 homens, idade média 68 ± 11 anos. Comparando o período de repouso versus EPAP, as alterações observadas foram: POAP (11,9 ± 3,8 para 17,1 ± 4,9 mmHg, p BACKGROND: Expiratory positive airway pressure (EPAP is used in after cardiac surgeries. However, its hemodynamic effects have not been clearly studied. OBJECTIVE: To evaluate the hemodynamic changes caused by EPAP in patients after cardiac surgery monitored by Swan-Ganz. METHODS: Patients at the first or second cardiac surgery postoperative period hemodynamically stable with a Swan-Ganz catheter were included in the study. They were assessed at rest and after using 10 cmH2O EPAP at random. The variables studied were: oxygen saturation, heart rate and respiratory rate, mean artery pressures and pulmonary artery mean pressures (MAP and PAMP, central venous pressure (CVP and pulmonary capillary wedge pressure

  5. Disagreement in primary study selection between systematic reviews on negative pressure wound therapy

    Directory of Open Access Journals (Sweden)

    Sauerland Stefan

    2008-06-01

    Full Text Available Abstract Background Primary study selection between systematic reviews is inconsistent, and reviews on the same topic may reach different conclusions. Our main objective was to compare systematic reviews on negative pressure wound therapy (NPWT regarding their agreement in primary study selection. Methods This retrospective analysis was conducted within the framework of a systematic review (a full review and a subsequent rapid report on NPWT prepared by the Institute for Quality and Efficiency in Health Care (IQWiG. For the IQWiG review and rapid report, 4 bibliographic databases (MEDLINE, EMBASE, The Cochrane Library, and CINAHL were searched to identify systematic reviews and primary studies on NPWT versus conventional wound therapy in patients with acute or chronic wounds. All databases were searched from inception to December 2006. For the present analysis, reviews on NPWT were classified as eligible systematic reviews if multiple sources were systematically searched and the search strategy was documented. To ensure comparability between reviews, only reviews published in or after December 2004 and only studies published before June 2004 were considered. Eligible reviews were compared in respect of the methodology applied and the selection of primary studies. Results A total of 5 systematic reviews (including the IQWiG review and 16 primary studies were analysed. The reviews included between 4 and 13 primary studies published before June 2004. Two reviews considered only randomised controlled trials (RCTs. Three reviews considered both RCTs and non-RCTs. The overall agreement in study selection between reviews was 96% for RCTs (24 of 25 options and 57% for non-RCTs (12 of 21 options. Due to considerable disagreement in the citation and selection of non-RCTs, we contacted the review authors for clarification (this was not initially planned; all authors or institutions responded. According to published information and the additional

  6. Negative pressure wound therapy in preseptal orbital cellulitis complicated with necrotizing fasciitis and preseptal abscess.

    Science.gov (United States)

    Contreras-Ruiz, José; Ramos-Cadena, Angeles; Solis-Arias, Patricia; Lozano-Platonoff, Adriana; Lopez-García, Lirio A; Contreras-Barrera, Martha E; Saenz-Corral, Claudia; de-la-Cruz-Garcia, Isabel; Cárdenas-Mejía, Alexander; Lopez-Oliver, Rubén

    2015-01-01

    Preseptal cellulitis (PC) may be locally complicated with abscess formation and necrotizing fasciitis. If not treated promptly and adequately, it may result in further complications. The authors report a series of patients where negative pressure wound therapy (NPWT) proved a safe and valuable adjunct therapy in avoiding complications of PC and in accelerating wound healing. A 4 patient case series. Four male patients (11 months to 58 years old) with unilateral complicated PC. Patients were admitted with PC and treated initially with specific intravenous antibiotic therapy. These patients did not respond adequately; therefore, surgical drainage and/or debridement were performed. After surgery, persistent edema and purulent discharge was observed prompting the need for adjunct NPWT every 48 to 72 hours. NPWT is the use of vacuum through a wound filler material covered with an airtight drape connected to a pump. Complete ophthalmologic examination was performed after each 48-hour cycle. Length of hospital stay, days from surgery to discharge, days from start of NPWT to discharge, clinical improvement, and safety. Four patients were diagnosed with PC between 2 and 5 days of evolution. Two diabetic adults developed the condition secondary to trauma, the adolescent as a result of a cosmetic piercing, and the infant associated to sinusitis. NPWT reached -125 mm·Hg, except for the infant who received -75 mm·Hg. The average number of days necessary for improvement with NPWT was 6.7 days. Only 2 patients required surgical reconstruction. Time from debridement to discharge was in average 13.5 days. No ocular complications were observed, and follow up was satisfactory with normal eyelid function and aesthetics and preserved visual acuity. NPWT proved to be safe and effective for treating locally complicated PC as an adjuvant therapy to antibiotic and surgical treatment that decreased the length of hospital stay, and the time for recovery in patients that were slow

  7. Comparison of health care costs and hospital readmission rates associated with negative pressure wound therapies.

    Science.gov (United States)

    Law, Amy; Cyhaniuk, Anissa; Krebs, Blake

    2015-03-01

    A retrospective national claims database analysis evaluated total and wound-related costs (eg, hospital readmission rates) for patients with chronic wounds treated with negative pressure wound therapy (NPWT), comparing NPWT-V (V.A.C. Therapy, KCI, an Acelity company, San Antonio, TX) and NPWT-O (other non-KCI models of NPWT, the brands of which were not known to the researchers). Patients with ≥ 1 NPWT claim from January 2009-June 2012 in outpatient settings in the United States were included, if they had continuous medical and pharmacy benefits for 12 months before the initial index date of their NPWT claim and at least 3 months post index. Mean total health care costs were assessed at 3 months and 12 months; wound-related hospital readmission rates were assessed at 3 months and 6 months. Cost differences between cohorts were analyzed by t test and readmission rates were analyzed by chi-square test. At 3 months, the cohort of NPWT-V patients was significantly younger (59.2 vs 63.6 years, P assessment, mean comorbidity scores did not differ between the NPWT-V group and the NPWT-O groups (3.38 vs 3.66). Total costs were lower for NPWT-V vs NPWT-O at 3 months ($35,498 vs $39,722, respectively; P = 0.08) and 12 months ($80,768 vs $111,212; P = 0.03). Significantly lower inpatient (P = 0.01), emergency room (P Wound-related readmission rates were significantly lower for NPWT-V at 3 months (5% vs 8%; P ≤ 0.01) and 6 months (6% vs 11%; P ≤ 0.01). For all wound types, NPWT-O patients had a 17-fold higher rate of switching to alternate NPWT models compared with NPWT-V patients. In this retrospective analysis, NPWT-V patients had lower total costs, lower wound-related costs, and lower hospital readmission rates than NPWT-O patients at all time points assessed.

  8. Cost analysis of Topical Negative Pressure (TNP Therapy for traumatic acquired wounds

    Directory of Open Access Journals (Sweden)

    Freytag, Sebastian

    2010-01-01

    Full Text Available Extended traumatic wounds require extended reconstructive operations and are accompanied by long hospitalizations and risks of infection, thrombosis and flap loss. In particular, the frequently used Topical Negative Pressure (TNP Therapy is regarded as cost-intensive. The costs of TNP in the context of traumatic wounds is analyzed using the method of health economic evaluation.All patients (n=67: 45 male, 22 female; average age 54 y with traumatically acquired wounds being treated with TNP at the university hospital of Goettingen in the period 01/01/2005–31/12/2007 comprise the basis for this analysis. The concept of activity-based costing based on clinical pathways according to InEK (National Institute for the Hospital Remuneration System systematic calculations was chosen for cost accounting. In addition, a special module system adaptable for individual courses of disease was developed. The treated wounds were located on a lower extremity in 83.7% of cases (n=56 and on an upper extremity in 16.3% of cases (n=11. The average time of hospitalization of the patients was 54 days. Twenty-five patients (37.31% exceeded the „maximum length of stay“ of their associated DRG (Diagnosis Related Groups. The total PCCL (patient clinical complexity level = patient severity score of 2.99 reflects the seriousness of disease. For the treatment of the 67 patients, total costs were $1,729,922.32 (1,249,176.91 €. The cost calculation showed a financial deficit of $–210,932.50 (–152,314.36 €. Within the entire treatment costs of $218,848.07 (158,030.19 €, 12.65% per case were created by TNP with material costs of $102,528.74 (74,036 €, representing 5.92% of entire costs. The cost of TNP per patient averaged $3,266.39 (2,358.66 €. The main portion of the costs was not – as is often expected – due to high material costs of TNP but instead to long-term treatments. Because of their complexity, the cases are insufficiently represented in the

  9. Insomnia complaints in lean patients with obstructive sleep apnea negatively affect positive airway pressure treatment adherence.

    Science.gov (United States)

    Eysteinsdottir, Bjorg; Gislason, Thorarinn; Pack, Allan I; Benediktsdottir, Bryndís; Arnardottir, Erna S; Kuna, Samuel T; Björnsdottir, Erla

    2017-04-01

    The objective of this study was to evaluate the determinants of long-term adherence to positive airway pressure treatment among patients with obstructive sleep apnea, with special emphasis on patients who stop positive airway pressure treatment within 1 year. This is a prospective long-term follow-up of subjects in the Icelandic Sleep Apnea Cohort who were diagnosed with obstructive sleep apnea between 2005 and 2009, and started on positive airway pressure treatment. In October 2014, positive airway pressure adherence was obtained by systematically evaluating available clinical files (n = 796; 644 males, 152 females) with moderate to severe obstructive sleep apnea (apnea-hypopnea index ≥15 events per h). The mean follow-up time was 6.7 ± 1.2 years. In total, 123 subjects (15.5%) returned their positive airway pressure device within the first year, 170 (21.4%) returned it later and 503 (63.2%) were still using positive airway pressure. The quitters within the first year had lower body mass index, milder obstructive sleep apnea, less sleepiness, and more often had symptoms of initial and late insomnia compared with long-term positive airway pressure users at baseline. Both initial and late insomnia were after adjustment still significantly associated with being an early quitter among subjects with body mass index insomnia are associated with early quitting on positive airway pressure among non-obese subjects. © 2016 European Sleep Research Society.

  10. Circulatory responses to lower body negative pressure in young Afghans and Danes

    DEFF Research Database (Denmark)

    Asmar, Ali; Bülow, Jens; Simonsen, Lene

    2014-01-01

    PURPOSE: We have previously shown that Afghans residing in Denmark for at least 12 years exhibit a lower 24-h ambulatory blood pressure compared to Danes. The purpose of this study was to test the hypothesis that the lower blood pressure reflects attenuated compensatory baroreflex responses...

  11. Expiratory Snoring Predicts Obstructive Pulmonary Disease in Patients with Sleep-disordered Breathing.

    Science.gov (United States)

    Alchakaki, Abdulrazak; Riehani, Anas; Shikh-Hamdon, Mulham; Mina, Nader; Badr, M Safwan; Sankari, Abdulghani

    2016-01-01

    Sleep-disordered breathing and chronic obstructive pulmonary disease are two common conditions that may present concomitantly. The effects of chronic obstructive pulmonary disease on the polysomnographic manifestation of sleep-disordered breathing have not been studied. We hypothesized that the presence of airflow obstruction could be predicted by the presence of expiratory upper airway narrowing during sleep in patients with sleep-disordered breathing. Ninety-three patients with sleep-disordered breathing (19 men; age, 51.6 yr; body mass index, 40.1 kg/m(2); apnea-hypopnea index, 37.4 events/h) were observed. Every patient had an in-lab polysomnography study and complete pulmonary function tests. Sleep and respiratory events were scored using American Academy of Sleep Medicine recommended scoring criteria. Expiratory snoring events were identified on polysomnography using microphone sensor and/or pressure flow sensor in each patient. The FEV1/FVC ratio less than 70 was used to define the presence of airflow obstruction. The proportion analysis demonstrated that patients with expiratory snoring have 11 times higher odds of having evidence of lower airway obstruction, defined as FEV1/FVC less than 70 (odds ratio [OR], 11.03; P snoring, smoking, 3% oxygen desaturation index, 2% oxygen desaturation index, and age (P snoring and smoking (OR, 11.76; confidence interval, 3.23-42.83; and OR, 9.95; confidence interval, 2.67-37.09), respectively. The multiple linear regression analysis revealed that the linear combination of mean SaO2 and expiratory snoring (P snoring predicts obstructive airway disorders. Patients with expiratory snoring and low mean oxygen saturation during sleep should be carefully assessed for pulmonary disorders such as asthma and chronic obstructive pulmonary disease.

  12. The use of a rigid disc to protect exposed structures in wounds treated with negative pressure wound therapy: effects on wound bed pressure and microvascular blood flow.

    Science.gov (United States)

    Anesäter, Erik; Borgquist, Ola; Torbrand, Christian; Roupé, K Markus; Ingemansson, Richard; Lindstedt, Sandra; Malmsjö, Malin

    2012-01-01

    There are increasing reports of deaths and serious complications associated with the use of negative pressure wound therapy (NPWT). Bleeding may occur in patients when NPWT is applied to a wound with exposed blood vessels or vascular grafts, possibly due to mechanical deformation and hypoperfusion of the vessel walls. Recent evidence suggests that using a rigid barrier disc to protect underlying tissue can prevent this mechanical deformation. The aim of this study was to examine the effect of rigid discs on the tissue exposed to negative pressure with regard to tissue pressure and microvascular blood flow. Peripheral wounds were created on the backs of eight pigs. The pressure and microvascular blood flow in the wound bed were measured when NPWT was applied. The wound was filled with foam, and rigid discs of different designs were inserted between the wound bed and the foam. The discs were created with or without channels (to accommodate exposed sensitive structures such as blood vessels and nerves), perforations, or a porous dressing that covered the underside of the discs (to facilitate pressure transduction and fluid evacuation). When comparing the results for pressure transduction to the wound bed, no significant differences were found using different discs covered with dressing, whereas pressure transduction was lower with bare discs. Microvascular blood flow in the wound bed decreased by 49 ± 7% when NPWT was applied to control wounds. The reduction in blood flow was less in the presence of a protective disc (e.g., -6 ± 5% for a dressing-covered, perforated disc, p = 0.006). In conclusion, NPWT causes hypoperfusion of superficial tissue in the wound bed. The insertion of a rigid barrier counteracts this effect. The placement of a rigid disc over exposed blood vessels or nerves may protect these structures from rupture and damage. © 2012 by the Wound Healing Society.

  13. Avaliação da frequência cardíaca à medida de pressão expiratória máxima estática e à manobra de Valsalva em jovens saudáveis Heart rate assessment during maximal static expiratory pressure and Valsalva maneuver in healthy young men

    Directory of Open Access Journals (Sweden)

    Vinicius Minatel

    2012-10-01

    Full Text Available CONTEXTUALIZAÇÃO: A medida de pressão expiratória máxima (PEmáx possui algumas contraindicações, pois acredita-se que as respostas obtidas nessa medida são similares às respostas encontradas na manobra de Valsalva (MV. OBJETIVOS: O objetivo principal é avaliar a resposta da frequência cardíaca (FC durante a medida da PEmáx e da MV em jovens saudáveis, em diferentes posturas, para identificar se e em qual condição a PEmáx reproduz as respostas obtidas na MV e, adicionalmente, estimar o trabalho realizado nas manobras. MÉTODO: Doze jovens saudáveis foram avaliados, orientados e familiarizados com as manobras. A MV foi composta por um esforço expiratório (40 mmHg durante 15 segundos contra um manômetro. A PEmáx foi executada segundo a American Thoracic Society. Ambas as medidas foram realizadas nas posturas supino e sentado. Para a análise da variação da frequência cardíaca (∆FC, índice de Valsalva (IV, índice da PEmáx (IPEmáx e o trabalho estimado das manobras (Wtotal, Wisotime, Wtotal/∆FCtotal e Wisotime/∆FCisotime , utilizou-se ANOVA two-way com post-hoc de Holm-Sidak (pBACKGROUND: The measure of the maximal expiratory pressure (MEP has some contraindications, as it is believed that the responses obtained in this measure are similar to the Valsalva maneuver (VM. OBJECTIVE: The main purpose of this study was to evaluate the heart rate responses (HR during the MEP and the VM measures in healthy young men into different postures aiming to identify whether and in which situation the MEP reproduces the responses obtained in the VM. Additionally we aim to estimate the workload realized during the maneuvers. METHOD: Twelve healthy young men were evaluated, instructed and familiarized with the maneuvers. The VM was characterized by an expiratory effort (40 mmHg against a manometer for 15 seconds. The MEP measure has been performed according to the American Thoracic Society. Both measures were performed at sitting

  14. Use of dynamic CT in acute respiratory distress syndrome (ARDS) with comparison of positive and negative pressure ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Helm, Emma; Babyn, Paul [Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Talakoub, Omid; Alirezaie, Javad [Ryerson University, Department of Electrical and Computer Engineering, Toronto, ON (Canada); Grasso, Francesco; Engelberts, Doreen; Kavanagh, Brian P. [Hospital for Sick Children and the University of Toronto, Departments of Anesthesia and Critical Care Medicine and the Program in Pulmonary and Experimental Medicine, Toronto (Canada)

    2009-01-15

    Negative pressure ventilation via an external device ('iron lung') has the potential to provide better oxygenation with reduced barotrauma in patients with ARDS. This study was designed to see if oxygenation differences between positive and negative ventilation could be explained by CT. Six anaesthetized rabbits had ARDS induced by repeated saline lavage. Rabbits were ventilated with positive pressure ventilation (PPV) and negative pressure ventilation (NPV) in turn. Dynamic CT images were acquired over the respiratory cycle. A computer-aided method was used to segment the lung and calculate the range of CT densities within each slice. Volumes of ventilated lung and atelectatic lung were measured over the respiratory cycle. NPV was associated with an increased percentage of ventilated lung and decreased percentage of atelectatic lung. The most significant differences in ventilation and atelectasis were seen at mid-inspiration and mid-expiration (ventilated lung NPV=61%, ventilated lung PPV=47%, p<0.001; atelectatic lung NPV=10%, atelectatic lung PPV 19%, p<0.001). Aeration differences were not significant at end-inspiration. Dynamic CT can show differences in lung aeration between positive and negative ventilation in ARDS. These differences would not be appreciated if only static breath-hold CT was used. (orig.)

  15. Effects of topical negative pressure therapy on tissue oxygenation and wound healing in vascular foot wounds.

    Science.gov (United States)

    Chiang, Nathaniel; Rodda, Odette A; Sleigh, Jamie; Vasudevan, Thodur

    2017-08-01

    Topical negative pressure (TNP) therapy is widely used in the treatment of acute wounds in vascular patients on the basis of proposed multifactorial benefits. However, numerous recent systematic reviews have concluded that there is inadequate evidence to support its benefits at a scientific level. This study evaluated the changes in wound volume, surface area, depth, collagen deposition, and tissue oxygenation when using TNP therapy compared with traditional dressings in patients with acute high-risk foot wounds. This study was performed with hospitalized vascular patients. Forty-eight patients were selected with an acute lower extremity wound after surgical débridement or minor amputation that had an adequate blood supply without requiring further surgical revascularization and were deemed suitable for TNP therapy. The 22 patients who completed the study were randomly allocated to a treatment group receiving TNP or to a control group receiving regular topical dressings. Wound volume and wound oxygenation were analyzed using a modern stereophotographic wound measurement system and a hyperspectral transcutaneous oxygenation measurement system, respectively. Laboratory analysis was conducted on wound biopsy samples to determine hydroxyproline levels, a surrogate marker to collagen. Differences in clinical or demographic characteristics or in the location of the foot wounds were not significant between the two groups. All patients, with the exception of two, had diabetes. The two patients who did not have diabetes had end-stage renal failure. There was no significance in the primary outcome of wound volume reduction between TNP and control patients on day 14 (44.2% and 20.9%, respectively; P = .15). Analyses of secondary outcomes showed a significant result of better healing rates in the TNP group by demonstrating a reduction in maximum wound depth at day 14 (36.0% TNP vs 17.6% control; P = .03). No significant findings were found for the other outcomes of changes

  16. Suction device for epidermal grafting in vitiligo: employing a syringe and a manometer to provide an adequate negative pressure.

    Science.gov (United States)

    Kim, H U; Yun, S K

    2000-07-01

    Suction devices for epidermal grafting need a suction pump to provide a negative pressure. The authors have developed a suction device in which a syringe and a manometer are employed to provide a negative pressure. The purpose of this study was to evaluate the efficacy of our suction device in vitiligo patients. The suction device was used to obtain epidermal blisters from the donor site. A CO2 laser was employed to remove the depigmented epidermis. The blister roofs of the donor site were harvested and were placed onto the recipient area. Ten patients with stable vitiligo were treated by epidermal grafting. Epidermal blisters were produced by suction in all patients. Also, all 10 patients regained repigmentation. Our suction blister device is simple and inexpensive to make, and it may become an alternative to the other suction devices.

  17. Comparison of Outcomes for Normal Saline and an Antiseptic Solution for Negative-Pressure Wound Therapy with Instillation.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Oliver, Noah; Garwood, Caitlin; Evans, Karen K; Steinberg, John S; Lavery, Larry A

    2015-11-01

    Negative-pressure wound therapy with instillation is an adjunctive treatment that uses periodic instillation of a solution and negative pressure for a wide diversity of wounds. A variety of solutions have been reported, with topical antiseptics as the most frequently chosen option. The objective of this study was to compare the outcomes of normal saline versus an antiseptic solution for negative-pressure wound therapy with instillation for the adjunctive treatment of infected wounds. This was a prospective, randomized, effectiveness study comparing 0.9% normal saline versus 0.1% polyhexanide plus 0.1% betaine for the adjunctive treatment of infected wounds that required hospital admission and operative débridement. One hundred twenty-three patients were eligible, with 100 patients randomized for the intention-to-treat analysis and 83 patients for the per-protocol analysis. The surrogate outcomes measured were number of operative visits, length of hospital stay, time to final surgical procedure, proportion of closed or covered wounds, and proportion of wounds that remained closed or covered at the 30-day follow-up. There were no statistically significant differences in the demographic profiles in the two cohorts except for a larger proportion of male patients (p = 0.004). There was no statistically significant difference in the surrogate outcomes with the exception of the time to final surgical procedure favoring normal saline (p = 0.038). The authors' results suggest that 0.9% normal saline may be as effective as an antiseptic (0.1% polyhexanide plus 0.1% betaine) for negative-pressure wound therapy with instillation for the adjunctive inpatient management of infected wounds. Therapeutic, II.

  18. Wound care in patients after median sternotomy by use of negative pressure dressing - Prevena Incision Management System and PICO system

    OpenAIRE

    Sevyan, Armen

    2016-01-01

    The negative pressure wound dressing is applied successfully for the prevention of wound complications after median sternotomy in obese patients with a high risk for this complication. Most wound infections are caused by skin flora. In the market are available various systems for the prevention of wound infection. We had to compare the objective of the influence of PICO dressing and Prevena dressing on wound healing in patients after conventional median sternotomy. In this cohort study 272...

  19. Evaluation of a Decision-Making Curriculum for Teaching Adolescents with Disabilities to Resist Negative Peer Pressure.

    Science.gov (United States)

    Khemka, Ishita; Hickson, Linda; Mallory, Sarah B

    2016-07-01

    This study was designed to assess the impact of a decision-making curriculum (PEER-DM) on the social peer relationship knowledge and self-protective decision-making skills of adolescents with disabilities in hypothetical situations involving negative peer pressure. A randomized design was used to assign students with disabilities from self-contained special education classes to an intervention group (n = 22) or a wait-list control group (n = 20). ANCOVA analyses, using pretest scores as covariates, indicated that students who were trained on PEER-DM had significantly higher effective decision-making action and correct risk perception scores, relative to participants in the control group. This study provides supporting evidence that PEER-DM is a promising intervention for students with disabilities, including those with identified autism spectrum disorders, during transition years to help them develop a better understanding of positive and negative peer relationships and learn systematic decision-making skills for improved handling of social situations in the school and community, especially situations involving negative peer pressure. The study adds credence to using systematic, strategy-based decision making interventions designed to address the cognitive, emotional and motivational processes underlying adolescent decision making in sensitive interpersonal situations involving peer pressure. The study points to the lack of preparedness to handle situations of negative peer pressure as a serious social and health risk for adolescents with disabilities that deserves urgent and concerted attention in transition services programming. Implications for future curriculum-development efforts and replication of treatment findings are discussed. Future research examining disability-specific patterns of decision-making in peer situations and comparisons with typically developing populations is recommended.

  20. A direct method for determining complete positive and negative capillary pressure curves for reservoir rock using the centrifuge

    Energy Technology Data Exchange (ETDEWEB)

    Spinler, E.A.; Baldwin, B.A. [Phillips Petroleum Co., Bartlesville, OK (United States)

    1997-08-01

    A method is being developed for direct experimental determination of capillary pressure curves from saturation distributions produced during centrifuging fluids in a rock plug. A free water level is positioned along the length of the plugs to enable simultaneous determination of both positive and negative capillary pressures. Octadecane as the oil phase is solidified by temperature reduction while centrifuging to prevent fluid redistribution upon removal from the centrifuge. The water saturation is then measured via magnetic resonance imaging. The saturation profile within the plug and the calculation of pressures for each point of the saturation profile allows for a complete capillary pressure curve to be determined from one experiment. Centrifuging under oil with a free water level into a 100 percent water saturated plug results in the development of a primary drainage capillary pressure curve. Centrifuging similarly at an initial water saturation in the plug results in the development of an imbibition capillary pressure curve. Examples of these measurements are presented for Berea sandstone and chalk rocks.

  1. Negative pressures in full-scale distribution system: field investigation, modelling, estimation of intrusion volumes and risk for public health

    Directory of Open Access Journals (Sweden)

    M. C. Besner

    2010-07-01

    Full Text Available Various investigations encompassing microbial characterization of external sources of contamination (soil and trenchwater surrounding water mains, flooded air-valve vaults, field pressure monitoring, and hydraulic and transient analyses were conducted in the same distribution system where two epidemiological studies showing an increase in gastrointestinal illness for people drinking tap water were conducted in the 1990's. Interesting results include the detection of microorganisms indicators of fecal contamination in all external sources investigated but at a higher frequency in the water from flooded air-valve vaults, and the recording of 18 negative pressure events in the distribution system during a 17-month monitoring period. Transient analysis of this large and complex distribution system was challenging and highlighted the need to consider field pressure data in the process.

  2. Impact of humidification and nebulization during expiratory limb protection: an experimental bench study.

    Science.gov (United States)

    Tonnelier, Alexandre; Lellouche, François; Bouchard, Pierre Alexandre; L'Her, Erwan

    2013-08-01

    Different filtering devices are used during mechanical ventilation to avoid dysfunction of flow and pressure transducers or for airborne microorganisms containment. Water condensates, resulting from the use of humidifiers, but also residual nebulization particles may have a major influence on expiratory limb resistance. To evaluate the influence of nebulization and active humidification on the resistance of expiratory filters. A respiratory system analog was constructed using a test lung, an ICU ventilator, heated humidifiers, and a piezoelectric nebulizer. Humidifiers were connected to different types of circuits (unheated, mono-heated, new-generation and old-generation bi-heated). Five filter types were evaluated: electrostatic, heat-and-moisture exchanger, standard, specific, and internal heated high-efficiency particulate air [HEPA] filter. Baseline characteristics were obtained from each dry filter. Differential pressure measurements were carried out after 24 hours of continuous in vitro use for each condition, and after 24 hours of use with an old-generation bi-heated circuit without nebulization. While using unheated circuits, measurements had to be interrupted before 24 hours for all the filtering devices except the internal heated HEPA filter. The heat-and-moisture exchangers occluded before 24 hours with the unheated and mono-heated circuits. The circuit type, nebulization practice, and duration of use did not influence the internal heated HEPA filter resistance. Expiratory limb filtration is likely to induce several major adverse events. Expiratory filter resistance increase is due mainly to the humidification circuit type, rather than to nebulization. If filtration is mandatory while using an unheated circuit, a dedicated filter should be used for ≤ 24 hours, or a heated HEPA for a longer duration.

  3. What's in a name? Expiratory tracheal narrowing in adults explained

    International Nuclear Information System (INIS)

    Leong, P.; Bardin, P.G.; Lau, K.K.

    2013-01-01

    Tracheomalacia, tracheobronchomalacia, and excessive dynamic airway collapse are all terms used to describe tracheal narrowing in expiration. The first two describe luminal reduction from cartilage softening and the latter refers to luminal reduction from exaggerated posterior membrane movement. Expiratory tracheal narrowing is a frequent occurrence that can cause symptoms of airway obstruction, such as dyspnoea, wheeze, and exercise intolerance. The accurate diagnosis and quantification of expiratory tracheal narrowing has important aetiological, therapeutic, and prognostic implications. The reference standard for diagnosis has traditionally been bronchoscopy; however, this method has significant limitations. Expiratory tracheal disorders are readily detected by four-dimensional dynamic volume multidetector computed tomography (4D-CT), an emerging, non-invasive method that will potentially enable detection and quantification of these conditions. This review discusses the morphological forms of expiratory tracheal narrowing and demonstrates the utility of 4D-CT in the diagnosis, quantification, and treatment of these important conditions

  4. Estimation of expiratory time constants via fuzzy clustering

    NARCIS (Netherlands)

    M.S. Lourens (M.S.); L. Ali (Lejla); B.W. van den Berg (Bart); A.F.M. Verbraak (Anton); J.M. Bogaard (Jan); H.C. Hoogsteden (Henk); R. Babuška (R.)

    2001-01-01

    markdownabstractObjective. In mechanically ventilated patients the expiratorytime constant provides information about respiratory mechanics. In thepresent study a new method, fuzzy clustering, is proposed to determine expiratory time constants. Fuzzy clustering differs from other methods since it

  5. The Ambivalence of Challenge Stressors: Time Pressure Associated with Both Negative and Positive Well-Being

    Science.gov (United States)

    Widmer, Pascale S.; Semmer, Norbert K.; Kalin, Wolfgang; Jacobshagen, Nicola; Meier, Laurenz L.

    2012-01-01

    According to the challenge-hindrance model, challenge stressors contain both stressful and challenging aspects, hindrance stressors only stressful aspects. Typically, negative outcomes of challenge stressors refer to well-being (strain), positive outcomes to so-called work outcomes (e.g., productivity, intention to quit). As both effects occur…

  6. Perceiving social pressure not to feel negative predicts depressive symptoms in daily life

    NARCIS (Netherlands)

    Dejonckheere, E.; Bastian, B.; Fried, E.I.; Murphy, S.C.; Kuppens, P.

    Background Western societies often overemphasize the pursuit of happiness, and regard negative feelings such as sadness or anxiety as maladaptive and unwanted. Despite this emphasis on happiness, the amount of people suffering from depressive complaints is remarkably high. To explain this apparent

  7. Proneness to worry is negatively associated with blood pressure and baroreflex sensitivity: further evidence of the blood pressure emotional dampening hypothesis.

    Science.gov (United States)

    Delgado, Luis Carlos; Vila, Jaime; Reyes del Paso, Gustavo A

    2014-02-01

    This study analyzes differences in blood pressure (BP) and baroreflex sensitivity (BRS) in relation to trait worry. 36 high worry and 21 low worry females were selected from scores on the Penn State Worry Questionnaire. Cardiovascular parameters were obtained during rest, a self-induced worry period, and defense reflex to intense auditory stimulation. Low worry participants exhibited greater BP during baseline and greater BRS both during baseline and the self-induced worry period than high worry participants. During the defense reflex, low worries present a greater increase in BP. It is concluded that low proneness to worry is associated with greater BP and BRS. Increases in BP during aversive stimulation activated a negative feedback mechanism to inhibit distress and emotional reactivity to negative stimulation. These results support the BP-emotional dampening hypothesis and suggest that the baroreflex can be a relevant mechanism in mediating this effect. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Efeitos de diferentes volumes correntes e da pressão expiratória final positiva sobre a troca gasosa na fístula broncopleural experimental Effects of different tidal volumes and positive end expiratory pressure on gas exchange in experimental bronchopleural fistula

    Directory of Open Access Journals (Sweden)

    Maria Gabriela Cavicchia Toneloto

    2008-09-01

    melhora e o débito da fístula é reduzido quando comparado ao volume corrente de 10ml/Kg. Um baixo volume resulta em hipercapnia e grave dessaturação. Finalmente, em qualquer volume corrente, PEEP aumenta o débito da fístula e diminui a ventilação alveolar.OBJECTIVES: The present study was designed to identify the effect of positive end expiratory pressure (PEEP and the ideal pulmonary tidal volume to ventilate animals with a surgically produced bronchopleural fistula, aiming to reduce fistula output without affecting gas exchange. METHODS: Hemodynamic and respiratory assessment of gas exchange was obtained in five, healthy, young, mechanically ventilated Large White pigs under volume controlled ventilation with FiO2 of 0.4 and an inspiration:expiration ratio of 1:2, keeping respiratory rate at 22 cpm. A bronchopleural fistula was produced by resection of the lingula. Underwater seal drainage was installed and the thorax was hermetically closed. Gas exchange and fistula output were measured with the animals ventilated sequentially with tidal volumes of 4 ml/kg, 7 ml/kg and 10 ml/Kg alternating zero of positive end expiratory pressure (ZEEP and PEEP of 10 cmH2O, always in the same order. RESULTS: These findings are attributed to reduced alveolar ventilation and ventilation/perfusion abnormalities and were attenuated with larger tidal volumes. PEEP increases air leak, even with low volume (of 2.0 ± 2.8mL to 31 ± 20.7mL; p= 0.006 and decreases alveolar ventilation in all tidal volumes. Alveolar ventilation improved with larger tidal volumes, but increased fistula output (10 mL/kg - 25.8 ± 18.3mL to 80.2 ± 43.9mL; p=0.0010. Low tidal volumes result in hypercapnia (ZEEP - Toneloto MGC, Terzi RGG, Silva WA, Moraes AC, Moreira MM 83.7± 6.9 mmHg and with PEEP 10 - 93 ± 10.1mmHg and severely decreased arterial oxygen saturation, about of 84%. CONCLUSIONS: The tidal volume of 7 ml/Kg with ZEEP was considered the best tidal volume because, despite moderate hypercapnia

  9. Negative pressure of the environmental air in the cleaning area of the materials and sterilization center: a systematic review

    Directory of Open Access Journals (Sweden)

    Caroline Lopes Ciofi-Silva

    Full Text Available ABSTRACT Objective: to analyze the scientific evidence on aerosols generated during cleaning activities of health products in the Central Service Department (CSD and the impact of the negative pressure of the ambient air in the cleaning area to control the dispersion of aerosols to adjacent areas. Method: for this literature systematic review the following searches were done: search guidelines, manuals or national and international technical standards given by experts; search in the portal and databases PubMed, Scopus, CINAHL and Web of Science; and a manual search of scientific articles. Results: the five technical documents reviewed recommend that the CSD cleaning area should have a negative differential ambient air pressure, but scientific articles on the impact of this intervention were not found. The four articles included talked about aerosols formed after the use of a ultrasonic cleaner (an increased in the contamination especially during use and pressurized water jet (formation of smaller aerosols 5μm. In a study, the aerosols formed from contaminated the hot tap water with Legionella pneumophila were evaluated. Conclusions: there is evidence of aerosol formation during cleanup activities in CSD. Studies on occupational diseases of respiratory origin of workers who work in CSD should be performed.

  10. The association of forced expiratory volume in one second and forced expiratory flow at 50% of the vital capacity, peak expiratory flow parameters, and blood eosinophil counts in exercise-induced bronchospasm in children with mild asthma.

    Science.gov (United States)

    Akar, H Haluk; Tahan, Fulya; Gungor, Hatice Eke

    2015-04-01

    Exercise-induced bronchoconstriction (EIB), which describes acute airway narrowing that occurs as a result of exercise, is associated with eosinophilic airway inflammation, bronchial hyperresponsiveness. The forced expiratory volume in one second (FEV1) is the most commonly used spirometric test in the diagnosis of EIB in exercise challenge in asthma. Other parameters such as forced expiratory flow at 50% of the vital capacity (FEF50%) and peak expiratory flow (PEF) are used less often in the diagnosis of EIB. The purpose of this study is to evaluate the association of FEV1 and FEF50%, PEF parameters, blood eosinophil counts in EIB in children with mild asthma. Sixty-seven children (male: 39, female: 28) with mild asthma were included in this study. Pulmonary functions were assessed before and at 1, 5, 10, 15, and 20 minutes after exercise. The values of spirometric FEV1, FEF50%, PEF, and blood eosinophil counts were evaluated in EIB in children with mild asthma. There was a positive correlation between FEV1 with FEF50% and PEF values (p<0.05; FEF50%, r=0.68; PEF, r=0.65). Also, a positive correlation was found between blood eosinophil counts and the values of spirometric FEV1, FEF50%, and PEF (p<0.05; FEV1, r=0.54; FEF50%, r=0.42; PEF, r=0.26). In addition to these correlations, in the exercise negative group for FEV1, the FEF50% and PEF values decreased more than the cutoff values in 3, and 2 patients, respectively. According to the presented study, eosinophil may play a major role in the severity of EIB in mild asthma. FEF50% and PEF values can decrease in response to exercise without changes in FEV1 in mild asthmatic patients.

  11. The Influence of the Bed with a Semiopen Hood on Bacteria Removal in a Negative-Pressure Isolation Room

    Directory of Open Access Journals (Sweden)

    Jeng-Min Huang

    2014-06-01

    Full Text Available This study numerically investigates the influence of a sickbed with a semiopened hood on bacteria removal in a negative-pressure isolation room. The parameters include air change rate, lying style, the length and height of hood, flow rate allotments, and the positions of outlets. The results show that the hood has excellent effect on the removal of contaminated air, which is much better than the case without hood. The flow field of patient's face up cough is very different from face side cough, and the contaminated air cannot be removed properly through one air outlet. There are three outlets on the hood, set straight above the patient's face and at both sides. The allotment of the exhaust flow rate of the upper outlet to that of side outlets is suggested to be 4: 6. When the total air change rate is above 6 ACH, the hood length has slight influence on pollutant removal. The increase of hood height has a negative impact when the patient coughs lying on back. When the side exhaust flow rate is high, the hood height has a slight impact for face side cough. The recommended air change rate for the negative-pressure ward with sickbed hood is above 5 ACH.

  12. Avaliação da função pulmonar de recém-nascidos com síndrome do desconforto respiratório em diferentes pressões finais expiratórias positivas Assessment of pulmonary function of preterm newborn infants with respiratory distress syndrome at different positive end expiratory pressure levels

    Directory of Open Access Journals (Sweden)

    Luiz C.T. Consolo

    2002-09-01

    Full Text Available RESUMO\tABSTRACT \t Objetivo: verificar as alterações da função pulmonar: complacência dinâmica (Cdyn, volume corrente inspiratório (V Tinsp, pressão arterial de dióxido de carbono (PaCO2, em recém-nascidos pré-termo com síndrome do desconforto respiratório. Pacientes e Métodos: estudo de caso controle, incluindo 11 pré-termos com idade gestacional Objective: to verify the alterations of pulmonary function in preterm newborn infants with respiratory distress syndrome (RDS. The parameters analyzed were Dynamic Compliance (Cdyn, Inspiratory Tidal Volume (TVinsp, partial arterial pressure of carbon dioxide (PaCO2. Methods: eleven preterm newborn infants, with gestational age < 35 weeks, and birth weight < 2.500 g, were include in a control case study. All infants presented RDS and were treated with 120 mg/Kg of porcine surfactant. The initial positive end expiratory pressure (PEEP was 3 cm H2O. A pneumotachograph with a graphical monitor was used to assess the pulmonary function. After each increase in the PEEP (4 and 6 cm H2O, there was an interval of 20 minutes before measuring the arterial data of pulmonary function and arterial gases. Results: there were three males and eight females (1:2,7 among the infants with RDS. The mean gestational age was 30.78. 2.05 weeks, ranging from 26 to 34 weeks. The increase in the PEEP from 3 to 6 cm H2O caused significant decrease in the TVinsp (6.46 ±3.43 to 4.20 ±2.35, P=0.0262. With the increase in the PEEP from 4 to 6 cm H2O, there was also a decrease in the TVinsp (5.98.± 3.33 to 4.20.± 2.35, (P=0.0044. Regarding the Cdyn, when there was an increase in the PEEP from 3 to 6 cm H2O, the reduction was statistically significant (0.58.± 0.27 to 0.46± 0.25, P=0.0408 and from 4 to 6 cm H2O, the reduction in the Cdyn was also important (0.77± 0.27 to 0.46± 0.25, (P=0.0164. Increases in the PEEP from 4 to 6 cm H2O caused increases in the PaCO2 (52.81± 15.49 to 64.90± 12.69, (P= 0,0141. A

  13. Superoxide dismutase levels and peak expiratory flow in asthmatic children

    Directory of Open Access Journals (Sweden)

    Arie Kurniasih

    2016-11-01

    Full Text Available Background Asthma is a chronic inflammatory process which involve variety of cells such as inflammatory mediators, reactive oxygen species (ROS, and cytokines. The inflammatory process would be exacerbated in the presence of oxidative stress. Superoxide dismutase (SOD is the first important enzyme to protect the respiratory tract against oxidative stress. The decreased of SOD has a correlation with increased of airway obstruction and bronchospasm. Objective To assess for a correlation between superoxide dismutase (SOD levels and peak expiratory flow, as well as to determine the impact of SOD levels for predicting asthma attacks. Methods We conducted a prospective cohort study at Dr. Sardjito Hospital, Yogyakarta, between February and April 2011 involving asthmatic children aged 5-18 years. Subjects’ serum SOD levels and peak expiratory flow were measured at the same time point. We then performed a prospective study following up on the same subjects to find out if they had a recurrent asthma attack within one month of the tests. We also reassessed their peak expiratory flow one month after blood specimens were obtained. Results Thirty-nine patients were enrolled in this study. There was no significant correlation between SOD level and peak expiratory flow [r=0.289; 95%CI -0.025 to 0.47; P=0.074]. However, older age was significantly associated with higher peak expiratory flow (=0.5; 95%CI 3.10 to 11.57; P=0.01. Lower levels of SOD increased the risk of asthma attacks in a month following the initial measurements (RR=5.5; 95%CI 1.6 to 18.9; P=0.009. Conclusion Superoxide dismutase (SOD level is not significantly associated with peak expiratory flow. However, we find a relationship between older age and higher peak expiratory flow and a relationship between lower SOD levels and risk of asthma attacks within one month following the tests.

  14. Comparisons of negative pressure wound therapy and ultrasonic debridement for diabetic foot ulcers: a network meta-analysis.

    Science.gov (United States)

    Wang, Ruran; Feng, Yanhua; Di, Bo

    2015-01-01

    a network meta-analysis was performed to compare the strength and weakness of negative pressure wound therapy (NPWT) with ultrasound debridement (UD) as for diabetic foot ulcers (DFU). PubMed, Ovid EMBASE, Web of Science, Cochrane library databases, and Chinese Biomedical Literature Database were searched till February 2015. Clinical compared studies of negative pressure wound therapy and ultrasound debridement were enrolled. The primary efficacy outcomes included healed ulcers, reduction of ulcer areas and time to closure. Secondary amputation including major and minor amputations was used to assess the safety profile. Out of 715 studies, 32 were selected which enrolled 2880 diabetic patients. The pooled analysis revealed that NPWT including vacuum assisted closure (VAC) and vacuum sealing drainage (VSD) were as efficacious as ultrasound debridement improving healed ulcers, odds ratio, 0.86; 95% CI 0.28 to 2.6 and 1.2; 95% CI 0.38 to 4, respectively. However, both were better to standard wound care in wound healing patients. Compared with the standard wound care treated diabetic foot ulcers, NPWT and UD resulted in a significantly superior efficacy in time to wound closure and decrement in area of wound. No significances were observed between NPWT and UD groups in both indicators. Fewer patients tended to receive amputation in NPWT and UD groups compared to standard wound care group. The results of the network meta-analysis indicated that negative pressure wound therapy was similar to ultrasound debridement for diabetic foot ulcers, but better than standard wound care both in efficacy and safety profile.

  15. Comparisons of negative pressure wound therapy and ultrasonic debridement for diabetic foot ulcers: a network meta-analysis

    Science.gov (United States)

    Wang, Ruran; Feng, Yanhua; Di, Bo

    2015-01-01

    Objective: a network meta-analysis was performed to compare the strength and weakness of negative pressure wound therapy (NPWT) with ultrasound debridement (UD) as for diabetic foot ulcers (DFU). Methods: PubMed, Ovid EMBASE, Web of Science, Cochrane library databases, and Chinese Biomedical Literature Database were searched till February 2015. Clinical compared studies of negative pressure wound therapy and ultrasound debridement were enrolled. The primary efficacy outcomes included healed ulcers, reduction of ulcer areas and time to closure. Secondary amputation including major and minor amputations was used to assess the safety profile. Results: Out of 715 studies, 32 were selected which enrolled 2880 diabetic patients. The pooled analysis revealed that NPWT including vacuum assisted closure (VAC) and vacuum sealing drainage (VSD) were as efficacious as ultrasound debridement improving healed ulcers, odds ratio, 0.86; 95% CI 0.28 to 2.6 and 1.2; 95% CI 0.38 to 4, respectively. However, both were better to standard wound care in wound healing patients. Compared with the standard wound care treated diabetic foot ulcers, NPWT and UD resulted in a significantly superior efficacy in time to wound closure and decrement in area of wound. No significances were observed between NPWT and UD groups in both indicators. Fewer patients tended to receive amputation in NPWT and UD groups compared to standard wound care group. Conclusions: The results of the network meta-analysis indicated that negative pressure wound therapy was similar to ultrasound debridement for diabetic foot ulcers, but better than standard wound care both in efficacy and safety profile. PMID:26550165

  16. Topical negative pressure therapy Recent experience of the department of plastic surgery at Ibn Sina University Hospital, Rabat, Morocco

    Directory of Open Access Journals (Sweden)

    Abdelmoughit Echchaoui

    2014-12-01

    Full Text Available IntroductionThe topical negative pressure therapy (TNP is a non-invasive method to treat chronic and acute wounds locally, using a continuous or intermittent negative pressure.The objective of this study is to present the first experience of this type of treatment used in clinical cases in our department. By presenting these cases, we highlight indication and efficiency of this new technique applied in relatively complicated situations, at the same time it also allows a significant improvement in treating injuries and chronic wounds.Materials and methodsIn this study, we present the recent experience of the Department of Reconstructive and Plastic Surgery of the University Hospital Center of Avicenne in Rabat. This therapy was used for the first time this year (in 2014, in three young patients who presented with chronic wounds associated with local and general factors that are unfavorable for the healing process.ResultsIn all three of our cases we obtained highly satisfactory clinical results.TNP allows wounds to bud in a shorter time, as well as a fast healing by second intention due to controlled wound healing or split-skin graft without using flaps. This enables to decrease the margin of error, the time and the number of dressing replacements, and to reduce the length of hospital stay.ConclusionThis is an expensive and specific equipment. However, the cost-benefit ratio analysis shows that it is an essential method that should be part of our therapeutic strategies.Keywords: loss of substance, negative pressure, budding, healing.  

  17. Negative Pressure Wound Therapy in Infected Wound following Posterior Spinal Instrumentation using Simple Self-assembled System: A Case Report

    Directory of Open Access Journals (Sweden)

    CW Chang

    2014-07-01

    Full Text Available Postoperative wound infection in an instrumented spine patient is often disastrous. Management includes implant removal leading to spine instability. Negative pressure wound therapy (NPWT applied to the spine surgical wound is one of the wound care technique with successful results. We report a case of a man who sustained Chance fracture of Lumbar 1 (L1 vertebra treated with long segment posterior instrumentation, who unfortunately developed Extended-spectrum beta-lactamase (ESBL positive E. coli infection one month after the operation. After careful debridement of the wound, the implant became exposed. Three cycles of NPWT were applied and the wound healed with granulation tissue completely covering the implant, and thus negating the need to remove the implant. In conclusion, the NPWT is a good alternative in postoperative wound management especially in an instrumented spine patient.

  18. Comparison of two negative pressure systems and syringe irrigation for root canal irrigation: an ex vivo study.

    Science.gov (United States)

    Adorno, C G; Fretes, V R; Ortiz, C P; Mereles, R; Sosa, V; Yubero, M F; Escobar, P M; Heilborn, C

    2016-02-01

    To compare in a laboratory study two negative pressure systems and syringe irrigation, regarding the delivery of a contrast solution (CS) to working length (WL) and into simulated lateral canals and the effective volume of irrigant aspirated during negative pressure irrigation. Twenty single-canaled incisor training models were constructed with six simulated lateral canals each (2, 4 and 6 mm to WL) and a size 40, 0.04 taper apical size canal. Each model underwent all irrigation procedures (EndoVac at WL (EndoVac-0) and WL-2 mm (EndoVac-2), iNP needle with negative pressure (iNPn) and syringe irrigation with the iNP needle (iNPs) and a 30-G side-slot needle placed at WL (SI0) and WL-2 (SI2) mm in a crossover design. CS was delivered at 4 mL min(-1) for 60 s with a peristaltic pump and a recovery device collected the volume (in mL) of irrigant suctioned by the negative pressure groups. The irrigation procedures were digitally recorded, and a still image of the 60-s time-point of irrigation was evaluated for CS distance to WL (in millimetres) after irrigation and penetration into lateral canals (3-point scale). Statistical tests used were Kruskal-Wallis and Dunn's test. EndoVac-0, iNPn and iNPs had median distances of CS to WL of 0 mm, followed by SI0 (0.2 mm), SI2 (0.7 mm) and EndoVac-2 (1.7 mm). There were no significant differences between EndoVac-0, iNPn, iNPs and SI0, but these were significantly different to SI2 and EndoVac-2 (P irrigation and that collected by iNPn (4 mL), but these were significantly greater than EndoVac-0 (2.8 mL, P irrigation procedures were ineffective at penetration into lateral canals. iNPn, EndoVac-0, iNPs and SI0 achieved greater irrigant penetration to WL. iNPn was able to collect a median volume of CS (4 mL) similar to that delivered by syringe irrigation (iNPp, SI0 and SI2). An adequate irrigant penetration into lateral canals could not be achieved by any of the systems. © 2015 International Endodontic Journal. Published by John

  19. Focal airtrapping at expiratory high-resolution CT: comparison with pulmonary function tests

    International Nuclear Information System (INIS)

    Kauczor, H.U.; Hast, J.; Heussel, C.P.; Mildenberger, P.; Thelen, M.; Schlegel, J.

    2000-01-01

    This study was undertaken to determine prevalence, extent, and severity of focal airtrapping at expiratory high-resolution CT, and to compare focal airtrapping with age, gender, pulmonary function tests, and blood gas analysis. Two-hundred seventeen patients with and without pulmonary disease underwent paired inspiratory/expiratory high-resolution CT. Six scan pairs with corresponding scan levels were visually assessed for focal - not diffuse - airtrapping using a four-point scale. Pulmonary function tests and blood gas analysis were available for correlation in all patients (mean interval 5 days). Focal airtrapping with lower lung predominance was observed in 80 % of patients. Twenty-six of 26 patients with restrictive lung function impairment exhibited focal airtrapping (mean score 2.4), whereas only 72 of 98 (74 %) patients with obstruction did (mean score 1.5; p < 0.05). Fifty-eight of 70 (83 %) patients with normal lung function (mean score 1.8) and 19 of 23 (83 %) patients with mixed impairment (mean score 1.8) had focal airtrapping. Focal airtrapping showed negative correlations with static lung volumes (-0.27 to -0.37; p < 0.001) in all patients and moderate positive correlations with dynamic parameters (0.3-0.4; p < 0.001) in patients with obstruction. No significant correlations were found with age, gender, and blood gas analysis. Visual assessment of focal - not diffuse - airtrapping at expiratory high-resolution CT does not correlate with physiological evidence of obstruction as derived from pulmonary function tests since the perception of focal airtrapping requires an adequate expiratory increase in lung density. (orig.)

  20. Hemodynamic responses to seated and supine lower body negative pressure - Comparison with +Gz acceleration

    Science.gov (United States)

    Polese, Alvese; Sandler, Harold; Montgomery, Leslie D.

    1992-01-01

    The hemodynamic responses to LBNP in seated subjects and in subjects in supine body positions were compared and were correlated with hemodynamic changes which occurred during a simulated (by centrifugation) Shuttle reentry acceleration with a slow onset rate of 0.002 G/s and during gradual onset exposures to +3 Gz and +4 Gz. Results demonstrate that seated LBNP at a level of -40 mm Hg can serve as a static simulator for changes in the heart rate and in mean blood pressure induced by gradual onset acceleration stress occurring during Shuttle reentry. The findings also provide a rationale for using LBNP during weightlessness as a means of imposing G-loading on the circulation prior to reentry.

  1. A switchable positive and negative air pressure device for efficient and gentle handling of nanofiber scaffolds

    Science.gov (United States)

    Hotaling, Nathan A.; Khristov, Vladimir; Maminishkis, Arvydas; Bharti, Kapil; Simon, Carl G.

    2017-10-01

    A scaffold handling device (SHD) has been designed that can switch from gentle suction to positive pressure to lift and place nanofiber scaffolds. In tissue engineering laboratories, delicate fibrous scaffolds, such as electrospun nanofiber scaffolds, are often used as substrates for cell culture. Typical scaffold handling procedures include lifting the scaffolds, moving them from one container to another, sterilization, and loading scaffolds into cell culture plates. Using tweezers to handle the scaffolds can be slow, can damage the scaffolds, and can cause them to wrinkle or fold. Scaffolds may also acquire a static charge which makes them difficult to put down as they cling to tweezers. An SHD has been designed that enables more efficient, gentle lifting, and placement of delicate scaffolds. Most of the parts to make the SHD can be purchased, except for the tip which can be 3D-printed. The SHD enables more reliable handling of nanofiber scaffolds that may improve the consistency of biomanufacturing processes.

  2. The differential effects of inspiratory, expiratory, and combined resistive breathing on healthy lung

    Directory of Open Access Journals (Sweden)

    Loverdos K

    2016-07-01

    Full Text Available Konstantinos Loverdos,1 Dimitrios Toumpanakis,1 Eleni Litsiou,1 Vassiliki Karavana,1 Constantinos Glynos,1 Christina Magkou,2 Stamatios Theocharis,3 Theodoros Vassilakopoulos1 1Department of Critical Care, Pulmonary Unit and Marianthi Simou Applied Biomedical Research and Training Center, Evangelismos General Hospital, University of Athens Medical School, 2Department of Pathology, Evangelismos General Hospital, 31st Department of Pathology, University of Athens Medical School, Athens, Greece Abstract: Combined resistive breathing (CRB is the hallmark of obstructive airway disease pathophysiology. We have previously shown that severe inspiratory resistive breathing (IRB induces acute lung injury in healthy rats. The role of expiratory resistance is unknown. The possibility of a load-dependent type of resistive breathing-induced lung injury also remains elusive. Our aim was to investigate the differential effects of IRB, expiratory resistive breathing (ERB, and CRB on healthy rat lung and establish the lowest loads required to induce injury. Anesthetized tracheostomized rats breathed through a two-way valve. Varying resistances were connected to the inspiratory, expiratory, or both ports, so that the peak inspiratory pressure (IRB was 20%–40% or peak expiratory (ERB was 40%–70% of maximum. CRB was assessed in inspiratory/expiratory pressures of 30%/50%, 40%/50%, and 40%/60% of maximum. Quietly breathing animals served as controls. At 6 hours, respiratory system mechanics were measured, and bronchoalveolar lavage was performed for measurement of cell and protein concentration. Lung tissue interleukin-6 and interleukin-1β levels were estimated, and a lung injury histological score was determined. ERB produced significant, load-independent neutrophilia, without mechanical or permeability derangements. IRB 30% was the lowest inspiratory load that provoked lung injury. CRB increased tissue elasticity, bronchoalveolar lavage total cell, macrophage

  3. Evidence-based recommendations for negative pressure wound therapy: treatment variables (pressure levels, wound filler and contact layer)--steps towards an international consensus.

    Science.gov (United States)

    Birke-Sorensen, H; Malmsjo, M; Rome, P; Hudson, D; Krug, E; Berg, L; Bruhin, A; Caravaggi, C; Chariker, M; Depoorter, M; Dowsett, C; Dunn, R; Duteille, F; Ferreira, F; Francos Martínez, J M; Grudzien, G; Ichioka, S; Ingemansson, R; Jeffery, S; Lee, C; Vig, S; Runkel, N; Martin, R; Smith, J

    2011-09-01

    Negative pressure wound therapy (NPWT) is becoming a commonplace treatment in many clinical settings. New devices and dressings are being introduced. Despite widespread adoption, there remains uncertainty regarding several aspects of NPWT use. To respond to these gaps, a global expert panel was convened to develop evidence-based recommendations describing the use of NPWT. In a previous communication, we have reviewed the evidence base for the use of NPWT within trauma and reconstructive surgery. In this communication, we present results of the assessment of evidence relating to the different NPWT treatment variables: different wound fillers (principally foam and gauze); when to use a wound contact layer; different pressure settings; and the impact of NPWT on bacterial bioburden. Evidence-based recommendations were obtained by a systematic review of the literature, grading of evidence and drafting of the recommendations by a global expert panel. Evidence and recommendations were graded according to the Scottish Intercollegiate Guidelines Network (SIGN) classification system. In general, there is relatively weak evidence on which to base recommendations for any one NPWT treatment variable over another. Overall, 14 recommendations were developed: five for the choice of wound filler and wound contact layer, four for choice of pressure setting and five for use of NPWT in infected wounds. With respect to bioburden, evidence suggests that reduction of bacteria in wounds is not a major mode of action of NPWT. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  4. Comparison of changes in tidal volume associated with expiratory rib cage compression and expiratory abdominal compression in patients on prolonged mechanical ventilation

    OpenAIRE

    Morino, Akira; Shida, Masahiro; Tanaka, Masashi; Sato, Kimihiro; Seko, Toshiaki; Ito, Shunsuke; Ogawa, Shunichi; Takahashi, Naoaki

    2015-01-01

    [Purpose] This study was designed to compare and clarify the relationship between expiratory rib cage compression and expiratory abdominal compression in patients on prolonged mechanical ventilation, with a focus on tidal volume. [Subjects and Methods] The subjects were 18 patients on prolonged mechanical ventilation, who had undergone tracheostomy. Each patient received expiratory rib cage compression and expiratory abdominal compression; the order of implementation was randomized. Subjects ...

  5. Intermittent negative pressure wound therapy with instillation for the treatment of persistent periprosthetic hip infections: a report of two cases

    Directory of Open Access Journals (Sweden)

    Söylemez MS

    2016-02-01

    Full Text Available Mehmet Salih Söylemez,1 Korhan Özkan,2 Bülent Kılıç,3 Samet Erinç41Department of Orthopaedics and Traumatology, Bingöl State Hospital, Bingöl, 2Department of Orthopaedics and Traumatology, Faculty of Medicine, Medeniyet University, Istanbul, 3Department of Orthopaedics and Traumatology, Orthopaedic Surgery Clinic, Istanbul Gelişim University, Tekirdağ, 4Department of Orthopaedics and Traumatology, Istanbul Medeniyet University, Göztepe Training and Research Hospital, Istanbul, TurkeyAbstract: Intermittent negative pressure wound therapy with instillation (NPWTi is starting to be used successfully to treat early periprosthetic infections of endoprostheses. However, few articles have reported the outcome of treatment with intermittent NPWTi for late persistent periprosthetic infections of the hip. In this study, we report two cases who underwent several rounds of radical wound debridement for the treatment of a late persistent periprosthetic infection of the hip. Intermittent NPWTi was used in both cases. Patients were treated successfully and there was no recurrence after 3 and 1 years of follow-up, respectively.Keywords: negative pressure, vacuum-assisted, periprosthetic infection, hip

  6. Negative pressure wound therapy with Bio-Dome dressing technology in the treatment of complex wounds: a case series.

    Science.gov (United States)

    Penny, H L; Spinazzola, J; Green, A; Rifkah, M; Faretta, M; Youshaw, D; Weaver, A; Zaki, P

    2014-04-01

    The treatment of complex wounds is difficult and not always effective. Various treatment options are used with varying degrees of success. Negative pressure wound therapy (NPWT) is a cost-efficient and effective way to help treat these wounds. The use of a vacuum device applies the negative pressure to the site of the wound and promotes waste removal and increases circulation and tissue formation. While various NPWT systems are currently on the market, we utilised the ConvaTec Engenex® system with Bio-DomeTM technology; however, our case study is not intended to advocate the specific use of this system, but instead focuses on the use of NPWT as a viable option for wound healing. Each of the following case study patients presented with difficult-to-heal wounds that failed traditional therapeutic approaches. Through the use of NPWT, our patients saw major wound size reductions. Each patient exhibited at least a 94% reduction in wound area, wound volume or both.

  7. Does Negative-Pressure Wound Therapy for the Open Abdomen Benefit the Patient? A Retrospective Cohort Study.

    Science.gov (United States)

    Krebs, Bojan; Jagrič, Tomaž

    2017-06-01

    Negative-pressure wound therapy (NPWT) is the most modern and sophisticated method of temporary abdominal closure. The aim of the study was to determine the significant predictors for mortality in patients with NPWT. University Clinical Centre Maribor, Slovenia MATERIALS AND METHODS:: The authors performed a retrospective cohort study of all patients treated with NPWT between January 1, 2011, and December 31, 2014. In the univariate analysis, the type of wound closure, more than 7 NPWT changes, the total days with NPWT, and time to wound closure were significantly associated with death of the patient. In the multivariate analysis, only the number of more than 7 NPWT changes was found as a significant predictor for death (P = .038). Negative-pressure wound therapy is a method of choice for the treatment of open abdomen if there is a clear indication. However, clinicians should try all measures to remove the NPWT system and close the abdomen as soon as possible because prolonged use is associated with significantly higher mortality.

  8. Closed-incision negative-pressure therapy in high-risk general surgery patients following laparotomy: a retrospective study.

    Science.gov (United States)

    Zaidi, A; El-Masry, S

    2017-03-01

    Surgical site infection (SSI) and wound dehiscence are dreaded complications following laparotomy in general surgical patients, and can potentially occur more often in various comorbid states. Negative-pressure wound therapy (NPWT) has a positive effect of on open and complicated wounds and so has been used for at-risk surgical incisions with the aim of redistributing lateral tension and holding incision edges together. The aim of the present study was to compare the rate of wound complications following laparotomy in high-risk general surgical patients with a clean incision treated with closed-incision negative-pressure therapy (ciNPT) with those receiving conventional care. A retrospective review was performed of the hospital medical records of patients who underwent laparotomy between 1 October 2010 and 31 March 2012. Records of 69 patients who received ciNPT and 112 who were managed by adherent gauze dressings were included in the final analysis. Two (2.9%) patients in the ciNPT group and 23 (20.5%) in the non-NPWT group developed a wound complication following laparotomy (P surgery patients considered to have risk of developing wound complications following laparotomy. © 2016 The Authors. Colorectal Disease published by John Wiley & Sons Ltd on behalf of Association of Coloproctology of Great Britain and Ireland.

  9. The efficacy of negative pressure wound therapy in the management of lower extremity trauma: review of clinical evidence.

    Science.gov (United States)

    Kanakaris, N K; Thanasas, C; Keramaris, N; Kontakis, G; Granick, Mark S; Giannoudis, P V

    2007-12-01

    A large number of aids have been conceived and introduced into clinical practice (nutritional supplements, local dressings, technical innovations) aimed at facilitating and optimising wound healing in both acute and chronic wound settings. Among these advances, negative pressure wound therapy (NPWT) has been introduced during the last 30 years, and has been analysed in over 400 manuscripts of the English, Russian and German literature. Until very recently, vacuum assisted closure (VAC) (KCI, TX, USA) has been the only readily available commercial device that provides localised negative pressure to the wound and is the predominant agent used to deliver NPWT featured in this review. We conducted a comprehensive review of the existing clinical evidence of the English literature on the applications of NPWT in the acute setting of trauma and burns of the lower extremity. Overall, 16 clinical studies have been evaluated and scrutinised as to the safety and the efficacy of this adjunct therapy in the specific environment of trauma. Effectiveness was comparable to the standard dressing and wound coverage methods. The existing clinical evidence justifies its application in lower limb injuries associated with soft tissue trauma.

  10. Measurement of negative ion mobility in O2 at high pressures using a point plate gap as an ion detector

    International Nuclear Information System (INIS)

    Okuyama, Y; Kimura, T; Suzuki, S; Itoh, H

    2012-01-01

    This paper describes the experimental results for negative ion mobility in O 2 at 0.5-2.0 atm. The ion mobility is observed using a high-pressure ion drift tube with a positive corona gap (Geiger counter), which is constructed from a point plate gap and acts as a negative ion detector. The variation of waveforms in the burst pulse is observed by varying the voltage applied to the ion detector to find the optimum voltage that must be applied across the ion detector in O 2 . This is investigated carefully to ensure the precise determination of mobility. The distortion of the electric field near the mesh electrode, which operates as the cathode of the ion detector and as the anode of the ion drift gap, is then examined to determine the optimum applied voltage to suppress its effect on the measurement of mobility. The mobility is subsequently measured at a reduced electric field intensity of 2.83 × 10 -3 to 2.83. The observed mobility of 2.31 ± 0.03 cm 2 V -1 s -1 in O 2 is concluded to be that of O 2 - . This value is also obtained in experiments over a wide range of gas pressures (0.5-2.0 atm) and drift lengths (1.00-9.00 cm). The mobilities of O 3 - and O - are also obtained experimentally. (paper)

  11. Comparison of changes in tidal volume associated with expiratory rib cage compression and expiratory abdominal compression in patients on prolonged mechanical ventilation.

    Science.gov (United States)

    Morino, Akira; Shida, Masahiro; Tanaka, Masashi; Sato, Kimihiro; Seko, Toshiaki; Ito, Shunsuke; Ogawa, Shunichi; Takahashi, Naoaki

    2015-07-01

    [Purpose] This study was designed to compare and clarify the relationship between expiratory rib cage compression and expiratory abdominal compression in patients on prolonged mechanical ventilation, with a focus on tidal volume. [Subjects and Methods] The subjects were 18 patients on prolonged mechanical ventilation, who had undergone tracheostomy. Each patient received expiratory rib cage compression and expiratory abdominal compression; the order of implementation was randomized. Subjects were positioned in a 30° lateral recumbent position, and a 2-kgf compression was applied. For expiratory rib cage compression, the rib cage was compressed unilaterally; for expiratory abdominal compression, the area directly above the navel was compressed. Tidal volume values were the actual measured values divided by body weight. [Results] Tidal volume values were as follows: at rest, 7.2 ± 1.7 mL/kg; during expiratory rib cage compression, 8.3 ± 2.1 mL/kg; during expiratory abdominal compression, 9.1 ± 2.2 mL/kg. There was a significant difference between the tidal volume during expiratory abdominal compression and that at rest. The tidal volume in expiratory rib cage compression was strongly correlated with that in expiratory abdominal compression. [Conclusion] These results indicate that expiratory abdominal compression may be an effective alternative to the manual breathing assist procedure.

  12. [Efficacy observation on application of negative pressure therapy in the treatment of superficial partial-thickness scald wound in children].

    Science.gov (United States)

    Shen, Chuan-an; Chai, Jia-ke; Tuo, Xiao-ye; Cai, Jian-hua; Li, Dong-jie; Zhang, Lin; Zhu, Hua; Cai, Jin-dong

    2013-02-01

    To observe the effect of negative pressure therapy in the treatment of superficial partial-thickness scald in children. Three hundred and seven children with superficial partial-thickness scald hospitalized from August 2009 to May 2012 were divided into negative pressure therapy group (NPT, n = 145) and control group (C, n = 162) according to the random number table. Patients in group NPT were treated with negative pressure from within post injury day (PID) 3 to PID 9 (with -16 kPa pressure), while traditional occlusive dressing method was used in group C. Changes in body temperature, wound healing condition, frequency of dressing change were compared between group NPT and group C. Bacterial culture results of wounds were compared before and after treatment in group NPT. Volume of drained transudate per one percent of wound area was recorded in group NPT on PID 1 to PID 3. Data were processed with t test or chi-square test. The incidence of high fever was significantly lower in group NPT (26.9%, 39/145) than in group C (63.6%, 103/162, χ(2) = 41.419, P wound epithelization was observed in 138 patients in group NPT, and in 7 patients there were a few residual wounds which healed after dressing change for 2 days. The wound healing time of patients in group NPT [(9.2 ± 0.6) d] was obviously shorter than that in group C [(10.1 ± 1.6) d, t = 6.895, P wound secretion of seventeen patients in group NPT before treatment, while no bacterium was discovered in all patients after treatment. Volumes of drainage fluid in group NPT were proportional to wound areas, which were respectively (9.8 ± 3.2), (6.2 ± 2.1), (4.1 ± 1.6) mL per one percent of wound area on PID 1, 2, and 3. NPT can decrease times of dressing change, and alleviate infection and inflammatory response by drainage of transudate, which promotes wound healing at last. NPT is proved to be a safe and effective approach for treatment of children with superficial partial-thickness scald.

  13. [Mode of debridement, negative-pressure therapy combined with tissue transplantation for treatment of complicated and refractory wounds].

    Science.gov (United States)

    Lei, Jin; Li, Hu-shan; Hao, Zhen-ming; Duan, Peng; Hao, Wen-jie

    2011-12-01

    To observe therapeutic effect of negative-pressure treatment combined with tissue transplantation on complicated and refractory wounds after debridement. After debridement, 20 patients with 20 complicated and refractory wounds hospitalized in our burn wards from May 2008 to June 2010 were randomly divided into treatment group (T, treated with negative-pressure from -19 kPa to -8 kPa, n = 10) and control group (C, covered with petrolatum gauze overlaid with saline gauze and dry gauze, n = 10) according to alternating method. On post treatment day (PTD) 4, 7, and 14, granulation tissues of wound surface in size of 4 mm × 3 mm × 2 mm were harvested for histopathological observation (including capillary growth, inflammatory cells, and collagen arrangement) with HE staining, and the numbers of vascular endothelial cells (VEC, with addition of rabbit anti-human coagulation factor VIII related antigen polyclonal antibody) and proliferation period cells (with addition of mouse anti-human Ki-67 monoclonal antibody) were counted by immunohistochemical staining. Data were processed with t test. Another 59 patients harboring 62 complicated and refractory wounds admitted to our burn ward at the same period were treated with the same mode of debridement, negative-pressure therapy, followed by timely skin or skin flap grafting. (1) Granulation tissue in T group grew more rapidly than that in C group. More capillaries and less inflammatory cells were observed in T group on PTD 7 as compared with those in C group. Collagen in T group on PTD 14 was more regular in arrangement than that in C group. The number of VEC per 400 times visual field in T group on PTD 4, 7, and 14 was respectively higher than that in C group (108.7 ± 11.2 vs. 31.0 ± 3.6, 138.0 ± 14.7 vs. 34.6 ± 4.5, 68.7 ± 6.9 vs. 55.1 ± 6.5, with t values from 4.62 to 30.28, P values all equal to 0.01). The number of proliferation period cell per 400 times visual field in T group on PTD 4 and 7 was respectively

  14. Effect of Negative Pressure on Proliferation, Virulence Factor Secretion, Biofilm Formation, and Virulence-Regulated Gene Expression of Pseudomonas aeruginosa In Vitro

    Directory of Open Access Journals (Sweden)

    Guo-Qi Wang

    2016-01-01

    Full Text Available Objective. To investigate the effect of negative pressure conditions induced by NPWT on P. aeruginosa. Methods. P. aeruginosa was cultured in a Luria–Bertani medium at negative pressure of −125 mmHg for 24 h in the experimental group and at atmospheric pressure in the control group. The diameters of the colonies of P. aeruginosa were measured after 24 h. ELISA kit, orcinol method, and elastin-Congo red assay were used to quantify the virulence factors. Biofilm formation was observed by staining with Alexa Fluor® 647 conjugate of concanavalin A (Con A. Virulence-regulated genes were determined by quantitative RT-PCR. Results. As compared with the control group, growth of P. aeruginosa was inhibited by negative pressure. The colony size under negative pressure was significantly smaller in the experimental group than that in the controls (p<0.01. Besides, reductions in the total amount of virulence factors were observed in the negative pressure group, including exotoxin A, rhamnolipid, and elastase. RT-PCR results revealed a significant inhibition in the expression level of virulence-regulated genes. Conclusion. Negative pressure could significantly inhibit the growth of P. aeruginosa. It led to a decrease in the virulence factor secretion, biofilm formation, and a reduction in the expression level of virulence-regulated genes.

  15. The Key Roles of Negative Pressure Breathing and Exercise in the Development of Interstitial Pulmonary Edema in Professional Male SCUBA Divers.

    Science.gov (United States)

    Castagna, Olivier; Regnard, Jacques; Gempp, Emmanuel; Louge, Pierre; Brocq, François Xavier; Schmid, Bruno; Desruelle, Anne-Virginie; Crunel, Valentin; Maurin, Adrien; Chopard, Romain; MacIver, David Hunter

    2018-01-03

    Immersion pulmonary edema is potentially a catastrophic condition; however, the pathophysiological mechanisms are ill-defined. This study assessed the individual and combined effects of exertion and negative pressure breathing on the cardiovascular system during the development of pulmonary edema in SCUBA divers. Sixteen male professional SCUBA divers performed four SCUBA dives in a freshwater pool at 1 m depth while breathing air at either a positive or negative pressure both at rest or with exercise. Echocardiography and lung ultrasound were used to assess the cardiovascular changes and lung comet score (a measure of interstitial pulmonary edema). The ultrasound lung comet score was 0 following both the dives at rest regardless of breathing pressure. Following exercise, the mean comet score rose to 4.2 with positive pressure breathing and increased to 15.1 with negative pressure breathing. The development of interstitial pulmonary edema was significantly related to inferior vena cava diameter, right atrial area, tricuspid annular plane systolic excursion, right ventricular fractional area change, and pulmonary artery pressure. Exercise combined with negative pressure breathing induced the greatest changes in these cardiovascular indices and lung comet score. A diver using negative pressure breathing while exercising is at greatest risk of developing interstitial pulmonary edema. The development of immersion pulmonary edema is closely related to hemodynamic changes in the right but not the left ventricle. Our findings have important implications for divers and understanding the mechanisms of pulmonary edema in other clinical settings.

  16. DC negative corona discharge in atmospheric pressure helium: transition from the corona to the ‘normal’ glow regime

    International Nuclear Information System (INIS)

    Hasan, Nusair; Farouk, Bakhtier; Antao, Dion S

    2014-01-01

    Direct current (dc) negative corona discharges in atmospheric pressure helium are simulated via detailed numerical modeling. Simulations are conducted to characterize the discharges in atmospheric helium for a pin plate electrode configuration. A self-consistent two-dimensional hybrid model is developed to simulate the discharges and the model predictions are validated with experimental measurements. The discharge model considered consists of momentum and energy conservation equations for a multi-component (electrons, ions, excited species and neutrals) gas mixture, conservation equations for each component of the mixture and state relations. A drift–diffusion approximation for the electron and the ion fluxes is used. A model for the external circuit driving the discharge is also considered and solved along with the discharge model. Many of the key features of a negative corona discharge, namely non-linear current–voltage characteristics, spatially flat cathode current density and glow-like discharge in the high current regime are displayed in the predictions. A transition to the ‘normal’ glow discharge from the corona discharge regime is also observed. The transition is identified from the calculated current–voltage characteristic curve and is characterized by the radial growth of the negative glow and the engulfment of the cathode wire. (paper)

  17. Stability of streambanks formed in partially saturated soils and effects of negative pore water pressures: the Sieve River (Italy)

    Science.gov (United States)

    Rinaldi, Massimo; Casagli, Nicola

    1999-01-01

    Streambanks of alluvial channels are usually composed of loose materials, which are unsaturated in ambient conditions. Unsaturated soils are subject to negative pore water pressures, which cause an apparent cohesion. The latter is the main factor in allowing the stability of near-vertical banks. Even during moderate in-bank flow events, the apparent cohesion can be strongly reduced as the material approaches full saturation; therefore, during the drawdown phase, as the confining pressure of the water in the channel disappears, a bank failure is likely to occur. Channel bed-level lowering along the Sieve River, Central Italy, has caused widespread bank instability. A geomorphological reconnaissance of forms and processes was followed by in situ tests to determine the shear strength of the banks. Interpretation of the tests and a streambank stability analysis were based on concepts of soil mechanics for unsaturated soils, in order to obtain relations between bank angle and height in limit equilibrium conditions. A stability chart was obtained with curves for different apparent cohesion values, and a stability analysis was performed taking into account the effects of flow events. In order to investigate the pore pressure effects, a series of piezo-tensiometers were installed in a streambank of the Sieve River. Data from a 1 year monitoring period show variations in pore water pressure and matric suction as a consequence of rainfall, evapotranspiration, and water stage variations. A planar failure with a tension crack occurred in the upper cohesive part of the bank during December 1996. The safety factor has been expressed as a function of the geometry of the bank and of the shear strength of the material. Safety factor variations through time are therefore shown as a function of seasonal variations in matric suction.

  18. Adapting a Vacuum Assisted Closure dressing to challenging wounds: negative pressure treatment for perineal necrotizing fasciitis with rectal prolapse in a newborn affected by acute myeloid leukaemia.

    Science.gov (United States)

    Negosanti, Luca; Aceti, Arianna; Bianchi, Tommaso; Corvaglia, Luigi; Negosanti, Francesca; Sgarzani, Rossella; Morselli, Paolo Giovanni; Cipriani, Riccardo; Negosanti, Massimino; Patrizi, Annalisa; Faldella, Giacomo

    2010-01-01

    We report the case of a newborn with acute myeloid leukaemia, who developed perineal necrotizing fasciitis due to Pseudomonas Aeruginosa, after twenty days of life. Following surgical debridement, she was effectively treated with topical negative pressure therapy (V.A.C.(R) device) with silver foam dressings, this achieved complete closure in thirteen days. Negative pressure therapy should be considered when conventional wound care fails to achieve complete wound closure, even in neonates.

  19. Effects of dressing type on 3D tissue microdeformations during negative pressure wound therapy: a computational study.

    Science.gov (United States)

    Wilkes, R; Zhao, Y; Kieswetter, K; Haridas, B

    2009-03-01

    Vacuum-assisted closure (VAC) therapy, also referred to as vacuum-assisted closure negative pressure wound therapy (VAC NPWT), delivered to various dermal wounds is believed to influence the formation of granulation tissue via the mechanism of microdeformational signals. In recent years, numerous experimental investigations have been initiated to study the cause-effect relationships between the mechanical signals and the transduction pathways that result in improved granulation response. To accurately quantify the tissue microdeformations during therapy, a new three-dimensional finite element model has been developed and is described in this paper. This model is used to study the effect of dressing type and subatmospheric pressure level on the variations in the microdeformational strain fields in a model dermal wound bed. Three-dimensional geometric models representing typical control volumes of NPWT dressings were generated using micro-CT scanning of VAC GranuFoam, a reticulated open-cell polyurethane foam (ROCF), and a gauze dressing (constructed from USP Class VII gauze). Using a nonlinear hyperfoam constitutive model for the wound bed, simulated tissue microdeformations were generated using the foam and gauze dressing models at equivalent negative pressures. The model results showed that foam produces significantly greater strain than gauze in the tissue model at all pressures and in all metrics (pobservation is consistent across all of the strain invariants assessed, i.e., epsilon(vol), epsilon(dist), the minimum and maximum principal strains, and the maximum shear strain. The distribution of the microdeformations and strain appears as a repeating mosaic beneath the foam dressing, whereas the gauze dressings appear to produce an irregular distribution of strains in the wound surface. Strain predictions from the developed computational model results agree well with those predicted from prior two-dimensional experimental and computational studies of foam

  20. Inspiratory and expiratory muscle training in subacute stroke: A randomized clinical trial.

    Science.gov (United States)

    Messaggi-Sartor, Monique; Guillen-Solà, Anna; Depolo, Marina; Duarte, Esther; Rodríguez, Diego A; Barrera, Maria-Camelia; Barreiro, Esther; Escalada, Ferran; Orozco-Levi, Mauricio; Marco, Ester

    2015-08-18

    To assess the effectiveness, feasibility, and safety of short-term inspiratory and expiratory muscle training (IEMT) in subacute stroke patients. Within 2 weeks of stroke onset, 109 patients with a first ischemic stroke event were randomly assigned to the IEMT (n = 56) or sham IEMT (n = 53) study group. The IEMT consisted of 5 sets of 10 repetitions, twice a day, 5 days per week for 3 weeks, at a training workload equivalent to 30% of maximal respiratory pressures. Patients and researchers assessing outcome variables were blinded to the assigned study group. The main outcome was respiratory muscle strength assessed by maximal inspiratory and expiratory pressures (PImax, PEmax). Respiratory complications at 6 months were also recorded. Both groups improved respiratory muscle strength during the study. IEMT was associated with significantly improved %PImax and %PEmax: effect size d = 0.74 (95% confidence interval [CI] 0.28-1.20) and d = 0.56 (95% CI 0.11-1.02), respectively. No significant training effect was observed for peripheral muscle strength. Respiratory complications at 6 months occurred more frequently in the sham group (8 vs 2, p = 0.042), with an absolute risk reduction of 14%. The number needed to treat to prevent one lung infection event over a follow-up of 6 months was 7. No major adverse events or side effects were observed. IEMT induces significant improvement in inspiratory and expiratory muscle strength and could potentially offer an additional therapeutic tool aimed to reduce respiratory complications at 6 months in stroke patients. This study provides Class II evidence that short-term training may have the potential to improve respiratory muscle strength in patients with subacute stroke. © 2015 American Academy of Neurology.

  1. Distribution assessment comparing continuous and periodic wound instillation in conjunction with negative pressure wound therapy using an agar-based model.

    Science.gov (United States)

    Rycerz, Anthony M; Slack, Paul; McNulty, Amy K

    2013-04-01

    Negative pressure wound therapy (NPWT) is a widely accepted and effective treatment for various wound types, including complex wounds. Negative pressure with instillation was initially used as a gravity-fed system whereby reticulated, open-cell foam in the wound bed was periodically exposed to cycles of soaking with instillation solution followed by NPWT. Recent publications have alluded to positive outcomes with continuous instillation, where fluid is delivered simultaneously with negative pressure. To evaluate the distribution of instillation solutions to wound beds in conjunction with negative pressure, agar-based models were developed and exposed to coloured instillation solutions to identify exposure intensity via agar staining. This model allowed comparison of continuous- versus periodic-instillation therapy with negative pressure. Continuous instillation at a rate of 30 cc/hour with negative pressure showed isolated exposure of instillation fluid to wound beds in agar wound models with and without undermining and tunnelling. In contrast, periodic instillation illustrated uniform exposure of the additive to the entire wound bed including undermined and tunnel areas, with increased staining with each instillation cycle. These findings suggest that periodic instillation facilitates more uniform exposure throughout the wound, including tunnels and undermining, to instillation solutions, thereby providing therapy consistent with the clinician-ordered treatment. © 2012 The Authors. International Wound Journal © 2012 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  2. Variant formula for predicting peak expiratory flow rate in pregnant ...

    African Journals Online (AJOL)

    Observed Peak expiratory flow rate (PEFR), Predicted and Variant PEFR values in 123 females at their reproductive ages, living in Kura local government area of Kano State, Nigeria and its environs were obtained. The prediction and variant formulae used were; PEFR= 0.36AGE – 0.47WT + 391.67 and K = mean CC x ...

  3. predicted peak expiratory flow in human and the clinical implication ...

    African Journals Online (AJOL)

    DR. AMINU

    values using formula developed by (Gregg, 1973) at 50th percentile for age, height and weight obtained from our study (Salisu ... Keywords: Peak expiratory flow, Asthma, Practice guidelines, reference values. INTRODUCTION. The National ... that the personal best PEF may be estimated after a. 2-to-3-week period in which ...

  4. Factors influencing peak expiratory flow in teenage boys | van ...

    African Journals Online (AJOL)

    Background. Peak expiratory flow (PEF) is a useful measure of pulmonary health status and is frequently utilised in asthm, management. Reduction in PEF is usually indicative of OIlS( of asthma symptoms. However, use can be made of PEF values only if normal values are known. The definition of normal range is always ...

  5. Peak Expiratory Flow Rate in Petroleum Depot Workers and Petrol ...

    African Journals Online (AJOL)

    Peak Expiratory Flow Rate (PEFR) values in litres per minute were determined in petrol depot loaders, petrol station attendants and in control subjects. The PEFR values were 315 ± 94, 386 + 91 and 529 + 94 litres/min. in depot workers, petrol attendants and control subjects respectively. The value in the control subjects ...

  6. variant formula for predicting peak expiratory flow rate in pregnant ...

    African Journals Online (AJOL)

    DR. AMINU

    The graph illustrates close association of variant formula with the observed values of PEFR obtained from the study. Variant formula may be useful in clinical setting to assess people with respiratory disorders especially asthma. Key words: Variant formula, Peak expiratory flow rate, Pregnancy, Kura local government area.

  7. Experience with the vacuum assisted closure negative pressure technique in the treatment of non-healing diabetic and dysvascular wounds.

    Science.gov (United States)

    Clare, Michael P; Fitzgibbons, Timothy C; McMullen, Scott T; Stice, R Colleen; Hayes, Dennis F; Henkel, Loree

    2002-10-01

    The purpose of this study is to report our experience with the Vacuum Assisted Closure (VAC) negative pressure technique in patients with non-healing wounds of the foot, ankle, and lower limb. We retrospectively reviewed 17 patients with non-healing wounds of the lower extremity who underwent treatment using the Vacuum Assisted Closure (VAC) device. Thirteen of 17 (76%) had diabetes mellitus, nine of whom were insulin-dependent, and 10 of whom had associated peripheral neuropathy. Eight of 17 (47%) had severe peripheral vascular disease. All had failed previous management with serial wound debridements and dressing changes; 15 of 17 (88%) had previously completed at least one course of oral antibiotics. Thirteen of 17 (76%) had previously undergone operative irrigation and debridement of the wounds; six of 17 (35%) had previously undergone revascularization procedures of the involved extremity. Five of 17 (29%) had wounds necessitating an amputation procedure prior to the present treatment; seven of 17 (41%) had failed treatment with local growth factors prior to the present treatment. Average length of treatment with the VAC device was 8.2 weeks. Fourteen of 17 (82%) wounds successfully healed; four underwent split-thickness skin grafting for wound closure; four were briefly treated with local growth factors; six were treated with only dressing changes following VAC treatment. Three of 17 (18%) wounds failed VAC treatment; all three patients had diabetes and had wounds located in the midfoot or forefoot; two of three had severe peripheral vascular disease. Our results indicate that the Vacuum Assisted Closure negative pressure technique is emerging as an acceptable option for wound care of the lower extremity. Not all patients are candidates for such treatment; those patients with severe peripheral vascular disease or smaller forefoot wounds may be best treated by other modalities. Larger wounds seem to be better suited for skin grafting or two-stage primary

  8. The effects of positive end-expiratory pressure in alveolar recruitment during mechanical ventilation in pigs Os efeitos da pressão positiva expiratória final no recrutamento alveolar durante a ventilação mecânica em porcos

    Directory of Open Access Journals (Sweden)

    Gabriel Ribeiro Madke

    2008-08-01

    Full Text Available PURPOSE: To evaluate the effects of alveolar recruitment based on mean airway pressure (MAP on pig lungs submitted to thoracotomy through blood gas exchange and hemodynamic parameters. METHODS: Twelve pigs weighting approximately 25Kg were intubated and ventilated on volume controlled ventilation (tidal volume 10ml/Kg, respiratory rate 16min, FiO2 1.0, inspiratory:expiratory ratio 1:2, PEEP 5cmH2O. The animals were then randomized into two groups: control and left lateral thoracotomy. The PEEP was increased at each 15-minute intervals to reach a MAP of 15, 20 and 25cmH2O, respectively. Hemodynamic, gas exchange and respiratory mechanic data were measured immediately before each PEEP change. RESULTS: There were no significant differences between both groups in all parameters analyzed (P=1.0. The PaO2, PaCO2, MAP, PAP and plateau pressure were significantly worse at MAP of 25cmH2O, when compared with the other values of MAP (P=0.001, P=0.039, P=0.001, P=0.016 e P=0.027, respectively. The best pulmonary performance according to the analyzed parameters was observed at MAP of 20cmH2O. CONCLUSION: PEEP adjusted to MAP of 20cmH2O resulted in best arterial oxygenation, without compromising the venous return, as opposed to MAP of 25cmH2O, which caused deterioration of gas exchange, hemodynamics and respiratory mechanic.OBJETIVO: Avaliar os efeitos do recrutamento alveolar baseado na pressão média das vias aéreas (Pmédia sobre os pulmões de porcos submetidos a toracotomia, através de dados gasométricos e hemodinâmicos. MÉTODOS: Doze porcos machos pesando em média 25Kg receberam indução anestésica, sendo intubados e ventilados a volume (FiO2=1.0, volume corrente=10 ml/kg/min, FR=16 cpm, relação I:E=1:2 e PEEP 5 mmHg. Os animais foram randomizados em dois grupos: controle e toracotomia lateral esquerda. Os valores de PEEP em cada grupo foram aumentados a cada 15 minutos para atingir valores de Pmédia de 15, 20 e 25cmH2O, sendo coletados

  9. An experimental study on the impacts of inspiratory and expiratory muscles activities during mechanical ventilation in ARDS animal model

    OpenAIRE

    Xianming Zhang; Juan Du; Weiliang Wu; Yongcheng Zhu; Ying Jiang; Rongchang Chen

    2017-01-01

    In spite of intensive investigations, the role of spontaneous breathing (SB) activity in ARDS has not been well defined yet and little has been known about the different contribution of inspiratory or expiratory muscles activities during mechanical ventilation in patients with ARDS. In present study, oleic acid-induced beagle dogs? ARDS models were employed and ventilated with the same level of mean airway pressure. Respiratory mechanics, lung volume, gas exchange and inflammatory cytokines w...

  10. High bacterial load in negative pressure wound therapy (NPWT) foams used in the treatment of chronic wounds.

    Science.gov (United States)

    Yusuf, Erlangga; Jordan, Xavier; Clauss, Martin; Borens, Olivier; Mäder, Mark; Trampuz, Andrej

    2013-01-01

    No earlier study has investigated the microbiology of negative pressure wound therapy (NPWT) foam using a standardized manner. The purpose of this study is to investigate the bacterial load and microbiological dynamics in NPWT foam removed from chronic wounds (>3 months). To determine the bacterial load, a standardized size of the removed NPWT foam was sonicated. The resulting sonication fluid was cultured, and the colony-forming units (CFU) of each species were enumerated. Sixty-eight foams from 17 patients (mean age 63 years, 71% males) were investigated. In 65 (97%) foams, ≥ 1 and in 37 (54%) ≥ 2 bacterial types were found. The bacterial load remained high during NPWT treatment, ranging from 10(4) to 10(6) CFU/ml. In three patients (27%), additional type of bacteria was found in subsequent foam cultures. The mean bacterial count ± standard deviation was higher in polyvinyl alcohol foam (6.1 ± 0.5 CFU/ml) than in polyurethane (5.5 ± 0.8 CFU/ml) (p = 0.02). The mean of log of sum of CFU/ml in foam from 125 mmHg (5.5 ± 0.8) was lower than in foam from 100 mmHg pressure (5.9 ± 0.5) (p = 0.01). Concluding, bacterial load remains high in NPWT foam, and routine changing does not reduce the load. © 2013 by the Wound Healing Society.

  11. The Bagautdinov dressing method: negative pressure wound therapy in a patient with an allergy to acrylate adhesive.

    Science.gov (United States)

    Daar, David A; Wirth, Garrett A; Evans, Gregory Rd; Carmean, Melissa; Gordon, Ian L

    2017-02-01

    Current embodiments of negative pressure wound therapy (NPWT) create a hermetically sealed chamber at the surface of the body using polyurethane foam connected to a vacuum pump, which is then covered by a flexible adhesive drape. Commercially available NPWT systems routinely use flexible polyethylene films that have a sticky side, coated with the same acrylate adhesives used in other medical devices such as ECG leads and grounding pads. Severe reactions to the acrylate adhesives in these other devices, although uncommon, have been reported. We describe the case of a 63-year-old woman with an intractable leg ulcer resulting from external-beam radiotherapy (XRT). Treatment with a standard commercial NPWT system induced severe inflammation of the skin in direct contact with drape adhesive. We successfully administered prolonged, outpatient NPWT to the patient using an alternative method (first described by Bagautdinov in 1986), using plain polyethylene film and petrolatum. The necessary hermetic seal is achieved by smearing the skin with petrolatum before applying the polyethylene film and activating the vacuum pump. The Bagautdinov method is a practical solution to the problem of adapting NPWT to patients with contact sensitivity or skin tears related to the adhesive compounds in the flexible drapes. Its use of a circumferential elastic wrap to maintain constant pressure on the seal probably limits the Bagautdinov technique to the extremities. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  12. The effect of blood volume loss on cardiovascular response to lower body negative pressure using a mathematical model

    Science.gov (United States)

    Karam, E. H.; Srinivasan, R. S.; Charles, J. B.; Fortney, S. M.

    1994-01-01

    Different mathematical models of varying complexity have been proposed in recent years to study the cardiovascular (CV) system. However, only a few of them specifically address the response to lower body negative pressure (LBNP), a stress that can be applied in weightlessness to predict changes in orthostatic tolerance. Also, the simulated results produced by these models agree only partially with experimental observations. In contrast, the model proposed by Melchior et al., and modified by Karam et al. is a simple representation of the CV system capable of accurately reproducing observed LBNP responses up to presyncopal levels. There are significant changes in LBNP response due to a loss of blood volume and other alterations that occur in weightlessness and related one-g conditions such as bedrest. A few days of bedrest can cause up to 15% blood volume loss (BVL), with consequent decreases in both stroke volume and cardiac output, and increases in heart rate, mean arterial pressure, and total peripheral resistance. These changes are more pronounced at higher levels of LBNP. This paper presents the results of a simulation study using our CV model to examine the effect of BVL on LBNP response.

  13. The effect of negative pressure wound therapy with antibacterial dressings or antiseptics on an in vitro wound model.

    Science.gov (United States)

    Matiasek, J; Domig, K J; Djedovic, G; Babeluk, R; Assadian, O

    2017-05-02

    The aim of this study was to investigate the bacterial bioburden in experimental in vitro wounds during the application of conventional negative pressure wound therapy (NPWT), with and without antimicrobial dressings (polyhexanide, silver), against NPWT instillation of octenidine. Experimental wounds produced in an in vitro porcine wound model were homogenously contaminated with bacterial suspension and treated with NPWT and different options. Group A: non-antimicrobial polyurethane foam dressing; group B: antimicrobial polyurethane foam dressing containing silver; group C: antimicrobial gauze dressing containing polyhexanide; group D: non-antimicrobial polyurethane foam dressing intermittently irrigated with octenidine; group E: negative control (non-antimicrobial polyurethane foam dressing without NPWT). Standard biopsies were harvested after 24 and 28 hours. This study demonstrated that the use of NPWT with intermitted instillation of octenidine (group D) or application of silver-based polyurethane foam dressings (group B) is significantly superior against Staphylococcus aureus colonisation in experimental wounds compared with non-antimicrobial polyurethane foam dressing (group A) after 48 hours. Surprisingly, the polyhexanide-based dressing (group C) used in this model showed no statistical significant effect compared with the control group (group E) after 24 or 48 hours of treatment. Both intermitted instillation of octenidine and silver-based dressings in standard NPWT were significantly superior compared with non-antimicrobial polyurethane foam dressings or PHMB coated gauze dressing after 48 hours.

  14. Ajustes da pressão positiva expiratória final ideal na síndrome do desconforto respiratório agudo na posição prona Best positive end expiratory pressure settlement in acute respiratory discomfort syndrome and prone position

    Directory of Open Access Journals (Sweden)

    Luiz Rogério de Carvalho Oliveira

    2008-03-01

    pulmonary mechanics, so we hypothesized that there is the necessity to optimize the ventilatory parameters after the patient is placed in prone position, especially the positive end expiratory pressure (PEEP values. The objective of this study valued the influence of the prone position at the calculation of the ideal PEEP, given a title by the best pulmonary complaisance and he compared the pulmonary alterations of mechanics, of oxygenation and of ventilation in the positions supine and prone. METHODS: Prospective study, taken place in the Irmandade Santa Casa de Misericórdia de São Paulo Intensive Care Service. Three fases have been compared. Fase 1: in supine position, after the best PEEP calculation. Fase 2: two hours after the patient was placed in prone position and the best PEEP was calculated. The patient was kept for 6 hours in this position. Fase 3: after this time, patient was placed in supine again and after two hours, a new best PEEP calculation and arterial gas analysis was done. And then fase1 versus fase 2, fase 2 versus fase 3, fase 3 versus fase1 were compared. RESULTS: There were no differences in the PEEP values found in all study fases: fase 1 = 14 ± 4.43; fase 2 = 14.73 ± 4.77 and fase 3 = 13.65 ± 4.92. CONCLUSIONS: There were no differences in best PEEP values between prone and supine position. Therefore, there is no need to recalculate the PEEP value after each position change.

  15. RESTING SYMPATHETIC BAROREFLEX SENSITIVITY IN SUBJECTS WITH LOW AND HIGH TOLERANCE TO CENTRAL HYPOVOLEMIA INDUCED BY LOWER BODY NEGATIVE PRESSURE

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    Carmen eHinojosa-Laborde

    2014-06-01

    Full Text Available Central hypovolemia elicited by orthostasis or hemorrhage triggers sympathetically-mediated baroreflex responses to maintain organ perfusion; these reflexes are less sensitive in patients with orthostatic intolerance, and during conditions of severe blood loss, may result in cardiovascular collapse (decompensatory or circulatory shock. The ability to tolerate central hypovolemia is variable and physiological factors contributing to tolerance are emerging. We tested the hypothesis that resting muscle sympathetic nerve activity (MSNA and sympathetic baroreflex sensitivity (BRS are attenuated in male and female subjects who have low tolerance (LT to central hypovolemia induced by lower body negative pressure (LBNP. MSNA and diastolic arterial pressure (DAP were recorded in 47 human subjects who subsequently underwent LBNP to tolerance (onset of presyncopal symptoms. LT subjects experienced presyncopal symptoms prior to completing LBNP of -60 mm Hg, and subjects with high tolerance (HT experienced presyncopal symptoms after completing LBNP after -60 mmHg. Contrary to our hypothesis, resting MSNA burst incidence was not different between LT and HT subjects, and was not related to time to presyncope. BRS was assessed as the slope of the relationship between spontaneous fluctuations in DAP and MSNA during 5 min of supine rest. MSNA burst incidence/DAP correlations were greater than or equal to 0.5 in 37 subjects (LT: n= 9; HT: n=28, and BRS was not different between LT and HT (-1.8 ± 0.3 vs. -2.2 ± 0.2 bursts•(100 beats-1•mmHg-1, p=0.29. We conclude that tolerance to central hypovolemia is not related to either resting MSNA or sympathetic BRS.

  16. In-flight Assessment of Lower Body Negative Pressure as a Countermeasure for Post-flight Orthostatic Intolerance

    Science.gov (United States)

    Charles, J. B.; Stenger, M. B.; Phillips, T. R.; Arzeno, N. M.; Lee, S. M. C.

    2009-01-01

    Introduction. We investigated the efficacy of combining fluid loading with sustained lower body negative pressure (LBNP) to reverse orthostatic intolerance associated with weightlessness during and immediately after Space Shuttle missions. Methods. Shuttle astronauts (n=13) underwent 4 hours of LBNP at -30 mm(Hg) and ingested water and salt ( soak treatment) during flight in two complementary studies. In the first study (n=8), pre-flight heart rate (HR) and blood pressure (BP) responses to an LBNP ramp (5-min stages of -10 mm(Hg) steps to -50 mm(Hg) were compared to responses in-flight one and two days after LBNP soak treatment. In the second study (n=5), the soak was performed 24 hr before landing, and post-flight stand test results of soak subjects were compared with those of an untreated cohort (n=7). In both studies, the soak was scheduled late in the mission and was preceded by LBNP ramp tests at approximately 3-day intervals to document the in-flight loss of orthostatic tolerance. Results. Increased HR and decreased BP responses to LBNP were evident early in-flight. In-flight, one day after LBNP soak, HR and BP responses to LBNP were not different from pre-flight, but the effect was absent the second day after treatment. Post-flight there were no between-group differences in HR and BP responses to standing, but all 5 treatment subjects completed the 5-minute stand test whereas 2 of 7 untreated cohort subjects did not. Discussion. Exaggerated HR and BP responses to LBNP were evident within the first few days of space flight, extending results from Skylab. The combined LBNP and fluid ingestion countermeasure restored in-flight LBNP HR and BP responses to pre-flight levels and provided protection of post-landing orthostatic function. Unfortunately, any benefits of the combined countermeasure were offset by the complexity of its implementation, making it inappropriate for routine application during Shuttle flights.

  17. Role of different negative pressure values in the process of infected wounds treated by vacuum-assisted closure: an experimental study.

    Science.gov (United States)

    Zhou, Min; Yu, Aixi; Wu, Gang; Xia, Chengyan; Hu, Xiang; Qi, Baiwen

    2013-10-01

    Vacuum-assisted closure (VAC) device is widely used to treat infected wounds in clinical work. Although the effect of VAC with different negative pressure values is well established, whether different negative pressures could result in varying modulation of wound relative cytokines was not clear. We hypothesise that instead of the highest negative pressure value the suitable value for VAC is the one which is the most effective on regulating wound relative cytokines. Infected wounds created on pigs' back were used to investigate the effects of varying negative pressure values of VAC devices. Wounds were treated with VAC of different negative pressure values or moist gauze, which was set as control. The VAC foam, semiocclusive dresses and moist gauze were changed on days 3, 5, 7 and 9 after wounds were created. When changing dressings, tissues from wounds were harvested for bacteria count and histology examination including Masson's trichrome stain and immunohistochemistry for microvessels. Western blot was carried out to test the expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Results showed that on days 3 and 5 the number of bacteria in wounds treated by VAC with 75, 150, 225 and 300 mmHg was significantly decreased compared with that in wounds treated by gauze and 0 mmHg pressure value. However, there was no difference in wounds treated with negative pressure values of 75 , 150, 225 and 300 mmHg at any time spot. Immunohistochemistry showed that more microvessels were generated in wounds treated by VAC using 75 and 150 mmHg negative pressure comparing with that using 225 and 300 mmHg on days 3 and 5. However this difference vanished on days 7 and 9. Morphological evaluation by Masson's trichrome staining showed increased collagen deposition in VAC of 75 and 150 mmHg compared with that in VAC of 225 and 300 mmHg. Western blot showed that the expression of VEGF and bFGF significantly increased when the wounds

  18. Influence of Changing the Diameter of the Bubble Generator Bottle and Expiratory Limb on Bubble CPAP: An in vitro Study

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    Chun-Shan Wu

    2012-12-01

    Conclusion: The size and submergence depth of an expiratory limb of a CPAP circuit, the diameter of the bubble generator bottle, and the compliance of the model lung all influence the magnitude and frequency of the transmitted pressure waveform. Therefore, these factors may affect lung volume recruitment and breathing efficiency in bubble CPAP.

  19. The Effects of Variable, Intermittent, and Continuous Negative Pressure Wound Therapy, Using Foam or Gauze, on Wound Contraction, Granulation Tissue Formation, and Ingrowth Into the Wound Filler

    Science.gov (United States)

    Malmsjö, Malin; Gustafsson, Lotta; Lindstedt, Sandra; Gesslein, Bodil; Ingemansson, Richard

    2012-01-01

    Objective: Negative pressure wound therapy (NPWT) is commonly used in the continuous mode. Intermittent pressure therapy (IPT) results in faster wound healing, but it often causes pain. Variable pressure therapy (VPT) has therefore been introduced to provide a smooth transition between 2 different pressure environments, thereby maintaining the negative pressure environment throughout the therapy. The aim of the present study was to examine the effects of IPT and VPT on granulation tissue formation. Method: A peripheral wound in a porcine model was treated for 72 hours with continuous NPWT (-80 mm Hg), IPT (0 to -80 mm Hg), or VPT (-10 to -80 mm Hg), using foam or gauze as wound filler. Wound contraction and force to remove the wound filler were measured. Biopsies from the wound bed were examined histologically for granulation tissue formation. Results: Intermittent pressure therapy and VPT produced similar results. Wound contraction was more pronounced following IPT and VPT than continuous NPWT. Intermittent pressure therapy and VPT resulted in the formation of more granulation tissue than continuous NPWT. Leukocyte infiltration and tissue disorganization were more prominent after IPT and VPT than after continuous NPWT. Granulation tissue grew into foam but not into gauze, regardless of the mode of negative pressure application, and less force was needed to remove gauze than foam. Conclusions: Wound contraction and granulation tissue formation is more pronounced following IPT and VPT than continuous NPWT. Granulation tissue grows into foam but not into gauze. The choice of negative pressure mode and wound filler is crucial in clinical practice to optimize healing while minimizing pain. PMID:22292101

  20. Homemade-device-induced negative pressure promotes wound healing more efficiently than VSD-induced positive pressure by regulating inflammation, proliferation and remodeling.

    Science.gov (United States)

    Liu, Jinyan; Hu, Feng; Tang, Jintian; Tang, Shijie; Xia, Kun; Wu, Song; Yin, Chaoqi; Wang, Shaohua; He, Quanyong; Xie, Huiqing; Zhou, Jianda

    2017-04-01

    Vacuum sealing drainage (VSD) is an effective technique used to promote wound healing. However, recent studies have shown that it exerts positive pressure (PP) rather than negative pressure (NP) on skin. In this study, we created a homemade device that could maintain NP on the wound, and compared the therapeutic effects of VSD-induced PP to those of our homemade device which induced NP on wound healing. The NP induced by our device required less time for wound healing and decreased the wound area more efficiently than the PP induced by VSD. NP and PP both promoted the inflammatory response by upregulating neutrophil infiltration and interleukin (IL)‑1β expression, and downregulating IL‑10 expression. Higher levels of epidermal growth factor (EGF), transforming growth factor (TGF)‑β and platelet-derived growth factor (PDGF), and lower levels of basic fibroblast growth factor (bFGF) were observed in the wound tissue treated with NP compared to the wound tissue exposed to PP. Proliferation in the wound tissue exposed to NP on day 10 was significantly higher than that in wound tissue exposed to PP. NP generated more fibroblasts, keratinized stratified epithelium, and less epithelia with stemness than PP. The levels of ccollagen Ⅰ and Ⅲ were both decreased in both the NP and PP groups. NP induced a statistically significant increase in the expression of fibronectin (FN) on days 3 and 10 compared to PP. Furthermore, the level of matrix metalloproteinase (MMP)‑13 increased in the NP group, but decreased in the PP group on day 3. NP also induced a decrease in the levels of tissue inhibitor of metalloproteinase (TIMP)‑1 and TIMP‑2 during the early stages of wound healing, which was significantly different from the increasing effect of PP on TIMP‑1 and TIMP‑2 levels at the corresponding time points. On the whole, our data indicate that our homemade device which induced NP, was more efficient than VSD‑induced PP on wound healing by

  1. Diagnostic methods to assess inspiratory and expiratory muscle strength

    OpenAIRE

    Caruso, Pedro; Albuquerque, André Luis Pereira de; Santana, Pauliane Vieira; Cardenas, Leticia Zumpano; Ferreira, Jeferson George; Prina, Elena; Trevizan, Patrícia Fernandes; Pereira, Mayra Caleffi; Iamonti, Vinicius; Pletsch, Renata; Macchione, Marcelo Ceneviva; Carvalho, Carlos Roberto Ribeiro

    2015-01-01

    Impairment of (inspiratory and expiratory) respiratory muscles is a common clinical finding, not only in patients with neuromuscular disease but also in patients with primary disease of the lung parenchyma or airways. Although such impairment is common, its recognition is usually delayed because its signs and symptoms are nonspecific and late. This delayed recognition, or even the lack thereof, occurs because the diagnostic tests used in the assessment of respiratory muscle strength are not w...

  2. Simultaneous irrigation and negative pressure wound therapy enhances wound healing and reduces wound bioburden in a porcine model.

    Science.gov (United States)

    Davis, Kathryn; Bills, Jessica; Barker, Jenny; Kim, Paul; Lavery, Lawrence

    2013-01-01

    Infected foot wounds are one of the most common reasons for hospitalization and amputation among persons with diabetes. The objective of the study was to investigate a new wound therapy system that employs negative pressure wound therapy (NPWT) with simultaneous irrigation therapy. For this study, we used a porcine model with full-thickness excisional wounds, inoculated with Pseudomonas aeruginosa. Wounds were treated for 21 days of therapy with either NPWT, NPWT with simultaneous irrigation therapy using normal saline or polyhexanide biguanide (PHMB) at low or high flow rates, or control. Data show that NPWT with either irrigation condition improved wound healing rates over control-treated wounds, yet did not differ from NPWT alone. NPWT improved bioburden over control-treated wounds. NPWT with simultaneous irrigation further reduced bioburden over control and NPWT-treated wounds; however, flow rate did not affect these outcomes. Together, these data show that NPWT with simultaneous irrigation therapy with either normal saline or PHMB has a positive effect on bioburden in a porcine model, which may translate clinically to improved wound healing outcomes. © 2013 by the Wound Healing Society.

  3. Platelet-rich plasma, bilayered acellular matrix grafting and negative pressure wound therapy in diabetic foot infection.

    Science.gov (United States)

    Deng, W; Boey, J; Chen, B; Byun, S; Lew, E; Liang, Z; Armstrong, D G

    2016-07-02

    Management and treatment of acute severe diabetic foot disease in patients with suboptimal glycaemic control is a critical issue in wound repair. This paper discusses the clinical efficacy of an aggressive surgical intervention combined with targeted use of regenerative medical therapies in limb preservation. Negative pressure wound therapy (NPWT), platelet-rich plasma (PRP), bilayered acellular matrix grafting and split-thickness skin grafting were combined to treat a patient with diabetes, foot necrotising fasciitis and gaseous gangrene. The wound was completely healed. The clinical outcome revealed that a multi-intervention strategy could be effective for large necrotising fasciitis wounds. Early clinical observation, suggests aggresive surgical intervention preserving intact tissue and targeted use of new regenerative technologies can lead to preservation of a limb. The authors have received no financial support for the material presented in this study outside of the scope of standard patient care reimbursement. This work was supported by the National Natural Science Foundation of China (NO. 81500596) awarded to Dr Wuquan Deng.

  4. Measurement of vancomycin hydrochloride concentration in the exudate from wounds receiving negative pressure wound therapy: a pilot study.

    Science.gov (United States)

    Ida, Yukiko; Matsumura, Hajime; Onishi, Masami; Ono, Sayaka; Imai, Ryutaro; Watanabe, Katsueki

    2016-04-01

    It has been reported that negative pressure wound therapy (NPWT) is effective in the treatment of contaminated wounds. We hypothesised that systemically administered antibiotics migrate to wound site effectively by NPWT, which provides the antibacterial effect. We measured and compared the concentrations of vancomycin in the exudate and blood serum. Eight patients with skin ulcers or skin defect wounds who were treated with NPWT and were administered an intravenous drip of vancomycin were enrolled in this study. The wound surfaces were muscle, muscle fascia or adipose tissue. We administered vancomycin intravenously to NPWT patients (1-3 g/day). The exudate was obtained using 500 ml V.A.C. ATS canisters without gel. Three days later, the concentrations of vancomycin were measured. The mean concentration of vancomycin in the exudate from NPWT was 67% of the serum vancomycin concentration. We found that concentrations of vancomycin in NPWT exudates are higher than the previously reported concentrations in soft tissue without NPWT. The proactive use of NPWT might be considered in cases of suspected wound contamination when a systemic antibiotic is administered. © 2014 The Authors. International Wound Journal © 2014 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  5. Wound management with negative pressure wound therapy in postoperative infection after open reconstruction of chronic Achilles tendon rupture.

    Science.gov (United States)

    Saku, Isaku; Kanda, Shotaro; Saito, Toshihiro; Fukushima, Takashi; Akiyama, Toru

    2017-01-01

    Deep infection after reconstruction of chronic Achilles tendon rupture is a major and intractable complication. We report a case of late deep infection following a surgery for chronic Achilles tendon rupture, and its simple and successful treatment with negative pressure wound therapy (NPWT). Six months following the reconstruction of chronic Achilles tendon rupture, a deep infection developed and reconstructed part of the tendon ruptured again. After appropriate debridement. There is no definitive treatment strategy for postoperative infection following open Achilles tendon repair. NPWT was applied to the wound, to promote wound healing and healthy granulation. In our case, NPWT promoted the wound healing and the infected Achilles tendon with tendon loss formed a healthy bridge with granulation tissue spontaneously. The patient resumed her normal activities of daily living, without requiring tendon transfer surgery. NPWT seems to be a simple and successful candidate for this situation. NPWT seems to be effective for the treatment of postoperative infection following Achilles tendon repair, even in cases of tendon loss. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Use of Bacteria- and Fungus-Binding Mesh in Negative Pressure Wound Therapy Provides Significant Granulation Tissue Without Tissue Ingrowth

    Science.gov (United States)

    Malmsjö, Malin; Lindstedt, Sandra; Ingemansson, Richard; Gustafsson, Lotta

    2014-01-01

    Objective: Bacteria- and fungus-binding mesh traps and inactivates bacteria and fungus, which makes it interesting, alternative, and wound filler for negative pressure wound therapy (NPWT). The aim of this study was to compare pathogen-binding mesh, black foam, and gauze in NPWT with regard to granulation tissue formation and ingrowth of wound bed tissue in the wound filler. Methods: Wounds on the backs of 8 pigs underwent 72 hours of NPWT using pathogen-binding mesh, foam, or gauze. Microdeformation of the wound bed and granulation tissue formation and the force required to remove the wound fillers was studied. Results: Pathogen-binding mesh produced more granulation tissue, leukocyte infiltration, and tissue disorganization in the wound bed than gauze, but less than foam. All 3 wound fillers caused microdeformation of the wound bed surface. Little force was required to remove pathogen-binding mesh and gauze, while considerable force was needed to remove foam. This is the result of tissue growth into the foam, but not into pathogen-binding mesh or gauze, as shown by examination of biopsy sections from the wound bed. Conclusions: This study shows that using pathogen-binding mesh as a wound filler for NPWT leads to a significant amount of granulation tissue in the wound bed, more than that with gauze, but eliminates the problems of ingrowth of the wound bed into the wound filler. Pathogen-binding mesh is thus an interesting wound filler in NPWT. PMID:24501617

  7. Negative Pressure Wound Therapy on Surgical Site Infections in Women Undergoing Elective Caesarean Sections: A Pilot RCT.

    Science.gov (United States)

    Chaboyer, Wendy; Anderson, Vinah; Webster, Joan; Sneddon, Anne; Thalib, Lukman; Gillespie, Brigid M

    2014-09-30

    Obese women undergoing caesarean section (CS) are at increased risk of surgical site infection (SSI). Negative Pressure Wound Therapy (NPWT) is growing in use as a prophylactic approach to prevent wound complications such as SSI, yet there is little evidence of its benefits. This pilot randomized controlled trial (RCT) assessed the effect of NPWT on SSI and other wound complications in obese women undergoing elective caesarean sections (CS) and also the feasibility of conducting a definitive trial. Ninety-two obese women undergoing elective CS were randomized in theatre via a central web based system using a parallel 1:1 process to two groups i.e., 46 women received the intervention (NPWT PICO™ dressing) and 46 women received standard care (Comfeel Plus(®) dressing). All women received the intended dressing following wound closure. The relative risk of SSI in the intervention group was 0.81 (95% CI 0.38-1.68); for the number of complications excluding SSI it was 0.98 (95% CI 0.34-2.79). A sample size of 784 (392 per group) would be required to find a statistically significant difference in SSI between the two groups with 90% power. These results demonstrate that a larger definitive trial is feasible and that careful planning and site selection is critical to the success of the overall study.

  8. Negative Pressure Wound Therapy on Surgical Site Infections in Women Undergoing Elective Caesarean Sections: A Pilot RCT

    Directory of Open Access Journals (Sweden)

    Wendy Chaboyer

    2014-09-01

    Full Text Available Obese women undergoing caesarean section (CS are at increased risk of surgical site infection (SSI. Negative Pressure Wound Therapy (NPWT is growing in use as a prophylactic approach to prevent wound complications such as SSI, yet there is little evidence of its benefits. This pilot randomized controlled trial (RCT assessed the effect of NPWT on SSI and other wound complications in obese women undergoing elective caesarean sections (CS and also the feasibility of conducting a definitive trial. Ninety-two obese women undergoing elective CS were randomized in theatre via a central web based system using a parallel 1:1 process to two groups i.e., 46 women received the intervention (NPWT PICO™ dressing and 46 women received standard care (Comfeel Plus® dressing. All women received the intended dressing following wound closure. The relative risk of SSI in the intervention group was 0.81 (95% CI 0.38–1.68; for the number of complications excluding SSI it was 0.98 (95% CI 0.34–2.79. A sample size of 784 (392 per group would be required to find a statistically significant difference in SSI between the two groups with 90% power. These results demonstrate that a larger definitive trial is feasible and that careful planning and site selection is critical to the success of the overall study.

  9. The Haiti earthquake: the provision of wound care for mass casualties utilizing negative-pressure wound therapy.

    Science.gov (United States)

    Gabriel, Allen; Gialich, Shelby; Kirk, Julie; Edwards, Sheriden; Beck, Brooke; Sorocéanu, Alexandra; Nelson, Scott; Gabriel, Cassie; Gupta, Subhas

    2011-10-01

    Many months after the devastating earthquake in January 2010, wounds remain a major disease burden in Haiti. Since January 2010, through the efforts of corporations, nonprofit charitable organizations, and medical professionals, advanced wound care techniques, including negative-pressure wound therapy (NPWT), have been introduced into the wound care regimens of various hospitals in Haiti. In June 2010, the authors completed their second volunteer trip at a Haitian hospital specializing in orthopedic wounds. The medical team was composed of a plastic surgeon, orthopedic surgeon, anesthesiologist, medical assistant, scrub technician, and registered nurse (specializing in plastic surgery and orthopedics). The authors' team supplied NPWT devices, reticulated open-cell foam dressings, and canisters donated by Kinetic Concepts, Inc, San Antonio, Texas, for use at the hospital. This report describes the medical challenges in postearthquake Haiti (including limb salvage and infection), benefits of adjunctive use of NPWT/reticulated open-cell foam, and current wound care status in a Haitian orthopedic hospital. The future role of NPWT in Haiti and during mass catastrophe in a least-developed country is also discussed.

  10. Negative Pressure Wound Therapy Applied Before and After Split-Thickness Skin Graft Helps Healing of Fournier Gangrene

    Science.gov (United States)

    Ye, Junna; Xie, Ting; Wu, Minjie; Ni, Pengwen; Lu, Shuliang

    2015-01-01

    Abstract Fournier gangrene is a rare but highly infectious disease characterized by fulminant necrotizing fasciitis involving the genital and perineal regions. Negative pressure wound therapy (NPWT; KCI USA Inc, San Antonio, TX) is a widely adopted technique in many clinical settings. Nevertheless, its application and effect in the treatment of Fournier gangrene are unclear. A 47-year-old male patient was admitted with an anal abscess followed by a spread of the infection to the scrotum, which was caused by Pseudomonas aeruginosa. NPWT was applied on the surface of the scrotal area and continued for 10 days. A split-thickness skin graft from the scalp was then grafted to the wound, after which, NPWT utilizing gauze sealed with an occlusive dressing and connected to a wall suction was employed for 7 days to secure the skin graft. At discharge, the percentage of the grafted skin alive on the scrotum was 98%. The wound beside the anus had decreased to 4 × 0.5 cm with a depth of 1 cm. Follow-up at the clinic 1 month later showed that both wounds had healed. The patient did not complain of any pain or bleeding, and was satisfied with the outcome. NPWT before and after split-thickness skin grafts is safe, well tolerated, and efficacious in the treatment of Fournier gangrene. PMID:25654376

  11. Abdominal expiratory muscle activity in anesthetized vagotomized neonatal rats.

    Science.gov (United States)

    Iizuka, Makito

    2009-05-01

    The pattern of respiratory activity in abdominal muscles was studied in anesthetized, spontaneously breathing, vagotomized neonatal rats at postnatal days 0-3. Anesthesia (2.0% isoflurane, 50% O(2)) depressed breathing and resulted in hypercapnia. Under this condition, abdominal muscles showed discharge late in the expiratory phase (E2 activity) in most rats. As the depth of anesthesia decreased, the amplitude of discharges in the diaphragm and abdominal muscles increased. A small additional burst frequently occurred in abdominal muscles just after the termination of diaphragmatic inspiratory activity (E1 or postinspiratory activity). Since this E1 activity is not often observed in adult rats, the abdominal respiratory pattern likely changes during postnatal development. Anoxia-induced gasping after periodic expiratory activity without inspiratory activity, and in most rats, abdominal expiratory activity disappeared before terminal apnea. These results suggest that a biphasic abdominal motor pattern (a combination of E2 and E1 activity) is a characteristic of vagotomized neonatal rats during normal respiration.

  12. Anomalous thermal expansion, negative linear compressibility, and high-pressure phase transition in ZnAu2(CN) 4 : Neutron inelastic scattering and lattice dynamics studies

    Science.gov (United States)

    Gupta, Mayanak K.; Singh, Baltej; Mittal, Ranjan; Zbiri, Mohamed; Cairns, Andrew B.; Goodwin, Andrew L.; Schober, Helmut; Chaplot, Samrath L.

    2017-12-01

    We present temperature-dependent inelastic-neutron-scattering measurements, accompanied by ab initio calculations of the phonon spectra and elastic properties as a function of pressure to quantitatively explain an unusual combination of negative thermal expansion and negative linear compressibility behavior of ZnAu2(CN) 4 . The mechanism of the negative thermal expansion is identified in terms of specific anharmonic phonon modes that involve bending of the -Zn-NC-Au-CN-Zn- linkage. The soft phonon at the L point at the Brillouin zone boundary quantitatively relates to the high-pressure phase transition at about 2 GPa. The ambient pressure structure is also found to be close to an elastic instability that leads to a weakly first-order transition.

  13. The use of a negative pressure wound management system in perineal wound closure after extralevator abdominoperineal excision (ELAPE) for low rectal cancer.

    Science.gov (United States)

    Sumrien, H; Newman, P; Burt, C; McCarthy, K; Dixon, A; Pullyblank, A; Lyons, A

    2016-09-01

    Perineal wound healing is a significant challenge after extralevator abdominoperineal excision (ELAPE) due to a high rate of wound breakdown. Negative pressure therapy has proven benefits in open wounds, and recently a negative pressure system has been developed for use on closed wounds at high risk of breakdown, such as apronectomy and hysterectomy. The aim of the present study was to determine whether negative pressure therapy applied to closed perineal wounds after ELAPE improved wound healing and compare outcomes to the published literature and outcomes from a historical cohort of patients who had undergone 'standard' abdominoperineal resection (APR) and primary closure of the perineal wounds. Prospective data on consecutive patients having ELAPE in the period from November 2012 to April 2015 were collected. The pelvic floor defect was reconstructed with biologic mesh. The adipose tissue layer was closed with vicryl sutures, a suction drain was left in the deep layer, the subcuticular layer and skin were closed, and the negative pressure system was applied. Any wound breakdown within the first 30 days postoperatively was recorded. Of the 32 consecutive ELAPE patients whose perineal wounds were closed within 30 days with the use of the negative pressure system, there was 1 patient with major perineal wound breakdown and 2 patients with a 1 cm superficial wound defect, which needed no further treatment. In the remaining 29 (90 %) patients, the perineal wounds healed fully without complications. Twenty-five patients underwent standard APR in 2010-2011 with primary closure of their perineal wounds. Ten out of 25(40 %) of patients who had undergone standard APR and primary closure of perineal wounds had major wound complications (p = 0.01). Our results suggest that after ELAPE the application of a negative pressure system to the perineal wound closed with biologic mesh may reduce perineal wound complications and may reduce the need for major perineal

  14. Účinek osmitýdenního plicního rehabilitačního programu na hrudní mobilitu a maximální vdechový a výdechový ústní tlak u pacientů s bronchiálním astmatem The effect of 8 week pulmonary rehabilitation programme on chest mobility and maximal inspiratory and expiratory mouth pressure in patients with bronchial asthma

    Directory of Open Access Journals (Sweden)

    Ivan Vařeka

    2008-04-01

    íjení hrudníku v obou úrovních a zvýšení hodnot maximálních nádechových a výdechových ústních tlaků. Zvýšení rozvíjení hrudníku a hodnot maximálních nádechových a výdechových ústních tlaků je velmi důležité pro nemocné s bronchiálním astmatem, neboť může vést ke snazšímu dýchání, menšímu nádechovému úsilí a menší únavě. Z tohoto důvodu by měla být respirační fyzioterapie součástí komprehensivní péče o nemocné s bronchiálním astmatem. Bronchial asthma (AB can lead not only to breathing disorders but also to musculoskeletal disorders. Breathing and musculoskeletal disorders can lead to health problems and decreased quality of life. These disorders may be also associated with psychosocial problems and could influence adult participation in various activities (physical activities and sports, activities of daily living – shopping, cleaning house, etc.. Breathlessness and cough are usually the most problematic symptoms of AB. Comprehensive care is based on medical treatment and non pharmacological treatment. Chest physiotherapy is an important part of the non pharmacological treatment, but the optimal medical treatment is also necessary for successful rehabilitation. The aim of this study was to find out if the pulmonary rehabilitation programme can influence the maximal inspiratory and expiratory mouth pressure and chest mobility of AB patients. The examined group consisted of 23 patients with AB. All AB patients had intermittent mild asthma and they were medically stable patients. All of them underwent an 8 week pulmonary rehabilitation programme (visits were twice a week, 30 minutes in length. The 8 week pulmonary rehabilitation programme was focused on breathing exercises (diaphragmatic breathing, activation of expiration, eff ective cough training, etc. and on soft tissue techniques for releasing thoracic and shoulder muscles and fascias. Maximal inspiratory and expiratory mouth pressure and chest mobility

  15. How bacterial cell division might cheat turgor pressure - a unified mechanism of septal division in Gram-positive and Gram-negative bacteria.

    Science.gov (United States)

    Erickson, Harold P

    2017-08-01

    An important question for bacterial cell division is how the invaginating septum can overcome the turgor force generated by the high osmolarity of the cytoplasm. I suggest that it may not need to. Several studies in Gram-negative bacteria have shown that the periplasm is isoosmolar with the cytoplasm. Indirect evidence suggests that this is also true for Gram-positive bacteria. In this case the invagination of the septum takes place within the uniformly high osmotic pressure environment, and does not have to fight turgor pressure. A related question is how the V-shaped constriction of Gram-negative bacteria relates to the plate-like septum of Gram-positive bacteria. I collected evidence that Gram-negative bacteria have a latent capability of forming plate-like septa, and present a model in which septal division is the basic mechanism in both Gram-positive and Gram-negative bacteria. © 2017 WILEY Periodicals, Inc.

  16. Rapid and variable-volume sample loading in sieving electrophoresis microchips using negative pressure combined with electrokinetic force.

    Science.gov (United States)

    Qi, Li-Ya; Yin, Xue-Feng; Zhang, Lei; Wang, Min

    2008-07-01

    A rapid and variable-volume sample loading scheme for chip-based sieving electrophoresis was developed by negative pressure combined with electrokinetic force. This was achieved by using a low-cost microvacuum pump and a single potential supply at a constant voltage. Both 12% linear polyacrylamide (LPA) with a high viscosity of 15000 cP and 2% hydroxyethylcellulose (HEC) with a low viscosity of 102 cP were chosen as the sieving materials to study the behavior and the versatility of the proposed method. To reduce the hydrodynamic resistance in the sampling channel, sieving material was only filled in the separation channel between the buffer waste reservoir (BW) to the edge of the crossed intersection. By applying a subambient pressure to the headspace of sample waste reservoir (SW), sample and buffer solution were drawn immediately from sample reservoir (S) and buffer reservoir (B) across the intersection to SW. At the same time, the charged sample in the sample flow was driven across the interface between the sample flow and the sieving matrix into the sieving material filled separation channel by the applied electric field. The injected sample plug length is in proportion with the loading time. Once the vacuum in SW reservoir was released to activate electrophoretic separation, flows from S and B to SW were immediately terminated by the back flow induced by the difference of the liquid levels in the reservoirs to prevent sample leakage during the separation stage. The sample consumption was about 1.7 x 10(2) nL at a loading time of 1 s for each cycle. Only 0.024 s was required to transport bias-free analyte to the injection point. It is easy to freely choose the sample plug volume in this method by simply changing the loading time and to inject high quality sample plug with non-distorted shape into the separation channel. The system has been proved to possess an exciting potential for improving throughput, repeatability, sensitivity and separation performance of

  17. Negative pressure wound therapy via vacuum-assisted closure following partial foot amputation: what is the role of wound chronicity?

    Science.gov (United States)

    Armstrong, David G; Lavery, Lawrence A; Boulton, Andrew J M

    2007-03-01

    Randomised clinical trials (RCTs) to evaluate diabetic foot wound therapies have systematically eliminated large acute wounds from evaluation, focusing only on smaller chronic wounds. The purpose of this study was to evaluate the proportion and rate of wound healing in acute and chronic wounds after partial foot amputation in individuals with diabetes treated with negative pressure wound therapy (NPWT) delivered by the vacuum-assisted closure (VAC) device or with standard wound therapy (SWT). This study constitutes a secondary analysis of patients enrolled in a 16-week RCT of NPWT: 162 open foot amputation wounds (mean wound size = 20.7 cm(2)) were included. Acute wounds were defined as the wounds less than 30 days after amputation, whereas chronic wounds as the wounds greater than 30 days. Inclusion criteria consisted of individuals older than 18 years, presence of a diabetic foot amputation wound up to the transmetatarsal level and adequate perfusion. Wound size and healing were confirmed by independent, blinded wound evaluators. Analyses were done on an intent-to-treat basis. There was a significantly higher proportion of acute wounds (SWT = 59; NPWT = 63) than chronic wounds (SWT = 26; NPWT = 14), evaluated in this clinical trial (P = 0.001). There was no significant difference in the proportion of acute and chronic wounds achieving complete wound closure in either treatment group. Despite this finding, the Kaplan-Meier curves demonstrated statistically significantly faster healing in the NPWT group in both acute (P = 0.030) and chronic wounds (P = 0.033). Among the patients treated with NPWT via the VAC, there was not a significant difference in healing as a function of chronicity. In both the acute and the chronic wound groups, results for patients treated with NPWT were superior to those for the patients treated with SWT. These results appear to indicate that wound duration should not deter the clinician from using this modality to treat complex wounds.

  18. Changes in body core temperatures and heat balance after an abrupt release of lower body negative pressure in humans

    Science.gov (United States)

    Tanabe, Minoru; Shido, Osamu

    1994-03-01

    Changes in body core temperature ( T cor) and heat balance after an abrupt release of lower body negative pressure (LBNP) were investigated in 5 volunteers under the following conditions: (1) an ambient temperature ( T a) of 20 °C or (2) 35 °C, and (3) T a of 25 °C with a leg skin temperature of 30°C or (4) 35°C. The leg skin temperature was controlled with water perfusion devices wound around the legs. Rectal ( T re), tympanic ( T ty) and esophageal ( T es) temperatures, skin temperatures (7 sites) and oxygen consumption were measured. The intensity of LBNP was adjusted so that the amount of blood pooled in the legs was the same under all conditions. When a thermal balance was attained during LBNP, application of LBNP was suddenly halted. The skin temperatures increased significantly after the release of LBNP under all conditions, while oxygen consumption hardly changed. The release of LBNP caused significant falls in T cor s under conditions (1) and (3), but lowered T cor s very slightly under conditions (2) and (4). The changes in T es were always more rapid and greater than those of T ty and T re. The falls in T ty and T re appeared to be explained by changes in heat balance, whereas the sharp drop of T es could not be explained especially during the first 8 min after the release of LBNP. The results suggest that a fall in T cor after a release of LBNP is attributed to an increase in heat loss due to reflexive skin vasodilation and is dependent on the temperature of venous blood returning from the lower body. It is presumed that T es may not be an appropriate indicator for T cor when venous return changes rapidly.

  19. Negative pressure wound therapy in the management of late deep infections after open reconstruction of achilles tendon rupture.

    Science.gov (United States)

    Mosser, Philipp; Kelm, Jens; Anagnostakos, Konstantinos

    2015-01-01

    Infection is a major complication after open reconstruction of Achilles tendon ruptures. We report on the use of vacuum-assisted closure (VAC) therapy in the treatment of late deep infections after open Achilles tendon reconstruction. Six patients (5 males [83.33%], 1 female [16.67%]; mean age, 52.8 [range 37 to 66] years) were been treated using an identical protocol. Surgical management consisted of debridement, lavage, and necrectomy of infected tendon parts. The VAC therapy was used for local wound preconditioning and infection management. A continuous negative pressure of 125 mm Hg was applied on each wound. For final wound closure, a split-thickness skin graft was performed. The skin graft healing process was also supported by VAC therapy during the first 5 days. The VAC dressings were changed a mean average of 3 (range 1 to 4) times until split-thickness skin grafting could be performed. The mean total duration of the VAC therapy was 13.6 ± 5.9 days. The mean hospital stay was 31.2 ± 15.9 days. No complications with regard to bleeding, seroma, or hematoma formation beneath the skin graft were observed. At a mean follow-up duration of 29.9 (range 4 to 65) months, no re-infection or infection persistence was observed. The VAC device seems to be a valuable tool in the treatment of infected tendons. The generalization of these conclusions should await the results of future studies with larger patient series. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Negative pressure wound therapy in the management of mine blast injuries of lower limbs: Lessons learnt at a tertiary care center.

    Science.gov (United States)

    Maurya, Sanjay; Srinath, N; Bhandari, P S

    2017-10-01

    Mine blast injuries of foot are devastating injuries that result in composite tissue loss or amputations. Negative pressure wound therapy has helped in the management of such combat-related wounds. The aim of this study was to report experiences gained in managing such injuries at a tertiary care center. 17 combatants who sustained mine blast injuries were included in this study. Severity of foot injury was assessed as per Foot and Ankle Severity Score. After wound debridement, negative pressure wound therapy was started and foot defect was appropriately reconstructed. Following wound healing, the foot was assessed for Foot and Ankle Severity Score in terms of impairment. The patients were then suitably rehabilitated by shoe modifications, orthosis, or custom-made prosthesis. Mean age of soldiers who sustained mine blast injuries was 30.2 years. The mean Foot and Ankle Severity Score was 3.76. Temporary wound closure was achieved using negative pressure wound therapy and it prevented local and systemic infection. The defect could be reconstructed appropriately using split skin graft, regional fasciocutaneous flap, or microvascular free flap. Mean time to definitive reconstructive procedure was 16.5 days. Mean Foot and Ankle Severity Score in terms of impairment was 4.11. All soldiers could be rehabilitated and were returned to their respective units and were able to perform sedentary duties assigned to them. The negative pressure wound therapy was helpful in preventing proximal amputations due to mine blast injury and was helpful in satisfactory reconstruction of foot defects.

  1. Major bleeding during negative pressure wound/V.A.C.®--therapy for postsurgical deep sternal wound infection--a critical appraisal

    NARCIS (Netherlands)

    van Wingerden, Jan J.; Segers, Patrique; Jekel, Lilian

    2011-01-01

    Negative-pressure wound therapy, commercially known as vacuum-assisted closure (V.A.C.®) therapy, has become one of the most popular (and efficacious) interim (prior to flap reconstruction) or definite methods of managing deep sternal wound infection. Complications such as profuse bleeding, which

  2. Prophylactic negative-pressure wound therapy after cesarean is associated with reduced risk of surgical site infection: a systematic review and meta-analysis.

    Science.gov (United States)

    Yu, Lulu; Kronen, Ryan J; Simon, Laura E; Stoll, Carolyn R T; Colditz, Graham A; Tuuli, Methodius G

    2018-02-01

    The objective of the study was to assess the effect of prophylactic negative-pressure wound therapy on surgical site infections and other wound complications in women after cesarean delivery. We searched Ovid Medline, Embase, SCOPUS, Cochrane Database of Systematic Reviews, and ClinicalTrials.gov. We included randomized controlled trials and observational studies comparing prophylactic negative-pressure wound therapy with standard wound dressing for cesarean delivery. The primary outcome was surgical site infection after cesarean delivery. Secondary outcomes were composite wound complications, wound dehiscence, wound seroma, endometritis, and hospital readmission. Heterogeneity was assessed using Higgin's I 2 . Relative risks with 95% confidence intervals were calculated using random-effects models. Six randomized controlled trials and 3 cohort studies in high-risk mostly obese women met inclusion criteria and were included in the meta-analysis. Six were full-text articles, 2 published abstracts, and 1 report of trial results in ClinicalTrials.gov. Studies were also heterogeneous in the patients included and type of negative-pressure wound therapy device. The risk of surgical site infection was significantly lower with the use of prophylactic negative-pressure wound therapy compared with standard wound dressing (7 studies: pooled risk ratio, 0.45; 95% confidence interval, 0.31-0.66; adjusted risk ratio, -6.0%, 95% confidence interval, -10.0% to -3.0%; number needed to treat, 17, 95% confidence interval, 10-34). There was no evidence of significant statistical heterogeneity (I 2  = 9.9%) or publication bias (Egger P = .532). Of the secondary outcomes, only composite wound complications were significantly reduced in patients receiving prophylactic negative-pressure wound therapy compared with standard dressing (9 studies: pooled risk ratio, 0.68, 95% confidence interval, 0.49-0.94). Studies on the effectiveness of prophylactic negative-pressure wound therapy at

  3. Negative pressure of the environmental air in the cleaning area of the materials and sterilization center: a systematic review.

    Science.gov (United States)

    Ciofi-Silva, Caroline Lopes; Hansen, Lisbeth Lima; Almeida, Alda Graciele Claudio Dos Santos; Kawagoe, Julia Yaeko; Padoveze, Maria Clara; Graziano, Kazuko Uchikawa

    2016-09-01

    to analyze the scientific evidence on aerosols generated during cleaning activities of health products in the Central Service Department (CSD) and the impact of the negative pressure of the ambient air in the cleaning area to control the dispersion of aerosols to adjacent areas. for this literature systematic review the following searches were done: search guidelines, manuals or national and international technical standards given by experts; search in the portal and databases PubMed, Scopus, CINAHL and Web of Science; and a manual search of scientific articles. the five technical documents reviewed recommend that the CSD cleaning area should have a negative differential ambient air pressure, but scientific articles on the impact of this intervention were not found. The four articles included talked about aerosols formed after the use of a ultrasonic cleaner (an increased in the contamination especially during use) and pressurized water jet (formation of smaller aerosols 5μm). In a study, the aerosols formed from contaminated the hot tap water with Legionella pneumophila were evaluated. there is evidence of aerosol formation during cleanup activities in CSD. Studies on occupational diseases of respiratory origin of workers who work in CSD should be performed. analisar as evidências científicas sobre aerossóis gerados durante atividades de limpeza dos produtos para saúde no Centro de Material e Esterilização (CME) e o impacto da pressão negativa do ar ambiente na área de limpeza para controle da dispersão de aerossóis para áreas adjacentes. para essa revisão sistemática de literatura foram realizadas: busca de diretrizes, manuais ou normas técnicas nacionais e internacionais indicadas por especialistas; busca no portal e bases de dados PUBMED, SCOPUS, Cinahl e Web of Science; e busca manual de artigos científicos. Os cinco documentos técnicos analisados preconizam que na área de limpeza do CME haja diferencial negativo de pressão do ar ambiente

  4. A combined inspiratory and expiratory muscle training program improves respiratory muscle strength and fatigue in multiple sclerosis.

    Science.gov (United States)

    Ray, Andrew D; Udhoji, Supriya; Mashtare, Terry L; Fisher, Nadine M

    2013-10-01

    To determine the effects of a short-duration, combined (inspiratory and expiratory), progressive resistance respiratory muscle training (RMT) protocol on respiratory muscle strength, fatigue, health-related quality of life, and functional performance in individuals with mild-to-moderate multiple sclerosis (MS). Quasi-experimental before-after trial. University rehabilitation research laboratory. Volunteers with MS (N=21) were divided into 2 groups: RMT (n=11; 9 women, 2 men; mean age ± SD, 50.9 ± 5.7y, mean Expanded Disability Status Scale score ± SD, 3.2 ± 1.9) and a control group that did not train (n=10; 7 women, 3 men; mean age ± SD, 56.2 ± 8.8y, mean Expanded Disability Status Scale score ± SD, 4.4 ± 2.1). Expanded Disability Status Scale scores ranged from 1 to ≤6.5. No patients withdrew from the study. Training was a 5-week combined progressive resistance RMT program, 3d/wk, 30 minutes per session. The primary outcome measures were maximal inspiratory pressure and expiratory pressure and the Modified Fatigue Impact Scale. All subjects completed secondary measures of pulmonary function, the six-minute walk test, the timed stair climb, the Multiple Sclerosis Self-Efficacy Scale, the Medical Outcomes Study 36-Item Short-Form Health Survey, and the Physical Activity Disability Scale. Maximal inspiratory pressure and expiratory pressure (mean ± SD) increased 35% ± 22% (Pfatigue (Modified Fatigue Impact Scale, Pmuscle strength and reduced fatigue in patients with mild to moderate MS. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Typical patterns of expiratory flow and carbon dioxide in mechanically ventilated patients with spontaneous breathing.

    Science.gov (United States)

    Rees, S E; Larraza, S; Dey, N; Spadaro, S; Brohus, J B; Winding, R W; Volta, C A; Karbing, D S

    2017-08-01

    Incomplete expiration of tidal volume can lead to dynamic hyperinflation and auto-PEEP. Methods are available for assessing these, but are not appropriate for patients with respiratory muscle activity, as occurs in pressure support. Information may exist in expiratory flow and carbon dioxide measurements, which, when taken together, may help characterize dynamic hyperinflation. This paper postulates such patterns and investigates whether these can be seen systematically in data. Two variables are proposed summarizing the number of incomplete expirations quantified as a lack of return to zero flow in expiration (IncExp), and the end tidal CO 2 variability (varETCO 2 ), over 20 breaths. Using these variables, three patterns of ventilation are postulated: (a) few incomplete expirations (IncExp  18) and small varETCO 2 . IncExp and varETCO 2 were calculated from data describing respiratory flow and CO 2 signals in 11 patients mechanically ventilated at 5 levels of pressure support. Data analysis showed that the three patterns presented systematically in the data, with periods of IncExp  18 having significantly lower variability in end-tidal CO 2 than periods with 2 ≤ IncExp ≤ 18 (p  18 to 2 ≤ IncExp ≤ 18 results in significant, rapid, change in the variability of end-tidal CO 2 p < 0.05. This study illustrates that systematic patterns of expiratory flow and end-tidal CO 2 are present in patients in supported mechanical ventilation, and that changes between these patterns can be identified. Further studies are required to see if these patterns characterize dynamic hyperinflation. If so, then their combination may provide a useful addition to understanding the patient at the bedside.

  6. Intermittent negative pressure applied to the lower limb increases foot macrocirculatory and microcirculatory blood flow pulsatility in people with spinal cord injury.

    Science.gov (United States)

    Sundby, Øyvind Heiberg; Høiseth, Lars Øivind; Irgens, Ingebjørg; Mathiesen, Iacob; Lundgaard, Eivind; Haugland, Hanne; Weedon-Fekjær, Harald; Sundhagen, Jon O; Sanbæk, Gunnar; Hisdal, Jonny

    2018-04-01

    Experimental prestudy and poststudy. Examine the acute effects of intermittent negative pressure (INP) applied to the lower limb on foot circulation in people with spinal cord injuries (SCIs). Vascular laboratory, Oslo University Hospital. Twenty-four people with SCI (median age 59 years, range 29-74) were exposed to lower leg INP (-40 mm Hg) using an air-tight pressure chamber connected to an INP generator. The contralateral leg was placed outside the pressure chamber. We continuously measured arterial blood flow velocity (ultrasound Doppler), skin blood flow (laser Doppler), skin temperature of the dorsum of the foot, heart rate (ECG) and systemic blood pressure (Finometer) during 5-min baseline (atmospheric pressure), followed by 10-min INP (alternating 10 s -40 mm Hg and 7 s atmospheric pressure), and 5-min post-INP (atmospheric pressure). Skin blood flow was measured on the foot placed outside the pressure chamber. A mixed effects regression model was applied to estimate the effect of INP on blood flow. To quantify flow fluctuations, we calculated cumulative up-and-down changes in arterial blood flow velocity per minute. Flow fluctuations increased during INP compared to baseline [32.3 cm/s/min (95% CI 26.9 to 37.7) vs. 15.2 cm/s/min (95% CI 9.8 to 20.6), P < 0.001]. Peak blood flow velocity and skin blood flow was reached 2-3 s after the onset of negative pressure and increased 33% (95% CI 16 to 46, P < 0.001) and 11% (95% CI -4.1 to 60, P = 0.14) above baseline, respectively. INP induced increased foot arterial blood flow fluctuations compared to baseline. The Norwegian Research Council provided funding to Otivio (grant: 241589).

  7. Treatment of open upper limb injuries with infection prevention and negative pressure wound therapy: a systematic review.

    Science.gov (United States)

    Ali, E; Raghuvanshi, M

    2017-12-02

    Open upper limb injuries requiring soft reconstruction can pose a dilemma for trauma surgeons when considering the treatment options. The British Orthopaedic Association and British Association of Plastic, Reconstructive and Aesthetic Surgeons Standard for Trauma (BOAST) have addressed the management of severe open lower limb fractures with the creation of the BOAST 4 guidelines. However, no such gold standard exists for the treatment of open injuries of the upper limb. Furthermore, treatment of these injuries is often more difficult and requires complicated strategies. Since the advent of negative pressure wound therapy (NPWT), there has been an improvement in wound care, though a focused review of its use in wound closure and infection prevention in the upper limb has not been published. We examine wound care management for open upper limb injuries with regard to the dressings applied, NPWT, wound closure and infection prevention. A systematic search of Medline, Cochrane and Google Scholar was performed using the key words. The key word searches were performed by two independent reviewers and 8,792 papers were found. Manuscripts between 1990 and 2010 were included, with the addition of key manuscripts before this date. Each manuscript was assessed by the two authors independently for methodology and validity Results: Approximately 120 manuscripts fulfilled selection criteria examining the influence of NPWT on open upper and lower limb injuries, and those examining infection risk in the same injuries. Of these 120 manuscripts, 28 were suitable for inclusion in the review. The systematic review is presented, allied to the BOAST 4 principles, examining the use of NPWT and the tools available for infection prevention for wounds of the upper and lower limb. The use of NPWT in conjunction with antibiotic-bead therapy improved the way in which open fractures of both the upper and lower limb are treated. Production of guidelines is warranted for the treatment of upper

  8. Economic and organizational sustainability of a negative-pressure portable device for the prevention of surgical-site complications

    Directory of Open Access Journals (Sweden)

    Foglia E

    2017-06-01

    Full Text Available Emanuela Foglia,1 Lucrezia Ferrario,1 Elisabetta Garagiola,1 Giuseppe Signoriello,2 Gianluca Pellino,3 Davide Croce,1,4 Silvestro Canonico3 1Centre for Health Economics, Social and Health Care Management - LIUC University, Castellanza, Italy; 2Department of Mental Health and Preventive Medicine, University of Campania “Luigi Vanvitelli”, Naples, Italy; 3School of Medicine, University of Campania “Luigi Vanvitelli”, Naples, Italy; 4School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South \tAfrica Purpose: Surgical-site complications (SSCs affect patients’ clinical pathway, prolonging their hospitalization and incrementing their management costs. The present study aimed to assess the economic and organizational implications of a portable device for negative-pressure wound therapy (NPWT implementation, compared with the administration of pharmacological therapies alone for preventing surgical complications in patients undergoing general, cardiac, obstetrical–gynecological, or orthopedic surgical procedures.Patients and methods: A total of 8,566 hospital procedures, related to the year 2015 from one hospital, were evaluated considering infection risk index, occurrence rates of SSCs, drug therapies, and surgical, diagnostic, and specialist procedures and hematological exams. Activity-based costing and budget impact analyses were implemented for the economic assessment.Results: Patients developing an SSC absorbed i 64.27% more economic resources considering the length of stay (€ 8,269±2,096 versus € 5,034±2,901, p<0.05 and ii 42.43% more economic resources related to hematological and diagnostic procedures (€ 639±117 versus € 449±72, p<0.05. If the innovative device had been used over the 12-month time period, it would have decreased the risk of developing SSCs; the hospital would have realized an average reduction in health care expenditure equal to −0.69% (−€ 483

  9. Spectral components of human cardiovascular responses to step changes in Lower Body Negative Pressure (LBNP) before and after 22 hour of 6 deg head down bed rest

    Science.gov (United States)

    Knapp, C. F.; Evans, J. M.; Grande, K. J.; Murphy, C. D.; Patwardhan, A. R.

    1992-01-01

    Changes in autonomic outflow to peripheral organs during the development of bedrest induced orthostatic intolerance have not been determined. Recent studies have indicated that spectral analysis provides an indirect assessment of these changes. Eight male subjects were studied before and after 22 hours of 6 degree head down bedrest plus Lasix (40 mg. P.P.). Cardiovascular spectra (using an autoregressive technique) were determined for heart rate (HR, ECG), arterial pressure (AP, Finapres), radial artery flow (RF, Hokansen) and respiration rate (RR, BoMed). Spectra were obtained from 2.5 minute segments during control, lower body negative pressure (minus 10, 20, 30, 40, 50 mmHg) and recovery. Bedrest increased HR spectra power in the low frequency (.001 to .041 Hz) range, increased RF power in the low and mid (.04 to .18 Hz) range and increased AP power in the high (.18 to .50 Hz) frequency range. Increasing levels of lower body negative pressure decreased HR power and increased RF power in the high frequency range and decreased AP power in the low frequency range. Since spectral power of HR in the high frequency range has been shown to indicate parasympathetically mediated regulation and power in the low and mid frequency ranges indicates a sympathetic / parasympathetic mixture, then both bedrest and lower body negative pressure appeared to shift sympathetic / parasympathetic balance toward sympathetic regulation of HR. The interpretation of the spectral content of AP and RF with respect to their autonomic origins remains unclear.

  10. Cracked rocks with positive and negative Poisson's ratio: real-crack properties extracted from pressure dependence of elastic-wave velocities

    Science.gov (United States)

    Zaitsev, Vladimir Y.; Radostin, Andrey V.; Dyskin, Arcady V.; Pasternak, Elena

    2017-04-01

    We report results of analysis of literature data on P- and S-wave velocities of rocks subjected to variable hydrostatic pressure. Out of about 90 examined samples, in more than 40% of the samples the reconstructed Poisson's ratios are negative for lowest confining pressure with gradual transition to the conventional positive values at higher pressure. The portion of rocks exhibiting negative Poisson's ratio appeared to be unexpectedly high. To understand the mechanism of negative Poisson's ratio, pressure dependences of P- and S-wave velocities were analyzed using the effective medium model in which the reduction in the elastic moduli due to cracks is described in terms of compliances with respect to shear and normal loading that are imparted to the rock by the presence of cracks. This is in contrast to widely used descriptions of effective cracked medium based on a specific crack model (e.g., penny-shape crack) in which the ratio between normal and shear compliances of such a crack is strictly predetermined. The analysis of pressure-dependences of the elastic wave velocities makes it possible to reveal the ratio between pure normal and shear compliances (called q-ratio below) for real defects and quantify their integral content in the rock. The examination performed demonstrates that a significant portion (over 50%) of cracks exhibit q-ratio several times higher than that assumed for the conventional penny-shape cracks. This leads to faster reduction of the Poisson's ratio with increasing the crack concentration. Samples with negative Poisson's ratio are characterized by elevated q-ratio and simultaneously crack concentration. Our results clearly indicate that the traditional crack model is not adequate for a significant portion of rocks and that the interaction between the opposite crack faces leading to domination of the normal compliance and reduced shear displacement discontinuity can play an important role in the mechanical behavior of rocks.

  11. End expiratory oxygen concentrations to predict central venous oxygen saturation: an observational pilot study

    Directory of Open Access Journals (Sweden)

    Steuerwald Michael

    2006-09-01

    Full Text Available Abstract Background A non-invasive surrogate measurement for central venous oxygen saturation (ScVO2 would be useful in the ED for assessing therapeutic interventions in critically ill patients. We hypothesized that either linear or nonlinear mathematical manipulation of the partial pressure of oxygen in breath at end expiration (EtO2 would accurately predict ScVO2. Methods Prospective observational study of a convenience sample of hemodialysis patients age > 17 years with existing upper extremity central venous catheters were enrolled. Using a portable respiratory device, we collected both tidal breathing and end expiratory oxygen and carbon dioxide concentrations, volume and flow on each patient. Simultaneous ScVO2 measurements were obtained via blood samples collected from the hemodialysis catheter. Two models were used to predict ScVO2: 1 Best-fit multivariate linear regression equation incorporating all respiratory variables; 2 MathCAD to model the decay curve of EtO2 versus expiratory volume using the least squares method to estimate the pO2 that would occur at Results From 21 patients, the correlation between EtO2 and measured ScVO2 yielded R2 = 0.11. The best fit multivariate equation included EtCO2 and EtO2 and when solved for ScVO2, the equation yielded a mean absolute difference from the measured ScVO2 of 8 ± 6% (range -18 to +17%. The predicted ScVO2 value was within 10% of the actual value for 57% of the patients. Modeling of the EtO2 curve did not accurately predict ScVO2 at any lung volume. Conclusion We found no significant correlation between EtO2 and ScVO2. A linear equation incorporating EtCO2 and EtO2 had at best modest predictive accuracy for ScVO2.

  12. Effectiveness of negative pressure wound therapy/closed incision management in the prevention of post-surgical wound complications: a systematic review and meta-analysis.

    Science.gov (United States)

    Sandy-Hodgetts, Kylie; Watts, Robin

    2015-01-01

    The treatment of post-surgical wound complications, such as surgical site infections and surgical wound dehiscence, generates a significant burden for patients and healthcare systems. The effectiveness of negative pressure wound therapy has been under investigation but to date no systematic review has been published in relation to its effectiveness in the prevention of surgical wound complications. To identify the effectiveness of negative pressure wound therapy in the prevention of post-surgical wound complications in adults with a closed surgical incision compared to standard surgical dressings. Male and female adults who have had negative pressure wound therapy applied to their surgical incision following a procedure in one of the following areas: trauma, cardiothoracic, orthopedic, abdominal, or vascular surgery.The intervention of interest was the use of negative pressure wound therapy directly over an incision following a surgical procedure; the comparator was standard surgical dressings.Both experimental and epidemiological study designs, including randomized controlled trials, pseudo-randomized trials, quasi-experimental studies, before and after studies, prospective and retrospective cohort studies, case control studies, and analytical cross sectional studies were sought.The primary outcome was the occurrence of post-surgical wound infection or dehiscence as measured by the following: surgical site infections - superficial and deep; surgical wound dehiscence; wound pain; wound seroma; wound hematoma. Published and unpublished studies in English from 1990 to 2013 were identified by searching a variety of electronic databases. Reference lists of all papers selected for retrieval were then searched for additional studies. Papers selected for retrieval were assessed by two independent reviewers for methodological validity prior to inclusion in the review using standardized critical appraisal instruments from the Joanna Briggs Institute Meta-Analysis of

  13. THE KÖLLIKER–FUSE NUCLEUS ACTS AS A TIMEKEEPER FOR LATE-EXPIRATORY ABDOMINAL ACTIVITY

    Science.gov (United States)

    JENKIN, SARAH E. M.; MILSOM, WILLIAM K.; ZOCCAL, DANIEL B.

    2018-01-01

    While the transition from the inspiratory to the post-inspiratory (post-I) phase is dependent on the pons, little attention has been paid to understanding the role of the pontine respiratory nuclei, specifically the Kölliker–Fuse nucleus (KF), in transitioning from post-I to the late expiratory (late-E) activity seen with elevated respiratory drive. To elucidate this, we used the in situ working heart-brainstem preparation of juvenile male Holtzman rats and recorded from the vagus (cVN), phrenic (PN) and abdominal nerves (AbN) during baseline conditions and during chemoreflex activation [with potassium cyanide (KCN; n = 13) or hypercapnia (8% CO2; n = 10)] to recruit active expiration. Chemoreflex activation with KCN increased PN frequency and cVN post-I and AbN activities. The inhibition of KF with isoguvacine microinjections (10 mM) attenuated the typical increase in PN frequency and cVN post-I activity, and amplified the AbN response. During hypercapnia, AbN late-E activity emerged in association with a significant reduction in expiratory time. KF inhibition during hypercapnia significantly decreased PN frequency and reduced the duration and amplitude of post-I cVN activity, while the onset of the AbN late-E bursts occurred significantly earlier. Our data reveal a negative relationship between KF-induced post-I and AbN late-E activities, suggesting that the KF coordinates the transition between post-I to late-E activity during conditions of elevated respiratory drive. PMID:28188852

  14. Major bleeding during negative pressure wound/V.A.C.® - therapy for postsurgical deep sternal wound infection - a critical appraisal

    Directory of Open Access Journals (Sweden)

    Segers Patrique

    2011-09-01

    Full Text Available Abstract Negative-pressure wound therapy, commercially known as vacuum-assisted closure (V.A.C.® therapy, has become one of the most popular (and efficacious interim (prior to flap reconstruction or definite methods of managing deep sternal wound infection. Complications such as profuse bleeding, which may occur during negative-pressure therapy but not necessarily due to it, are often attributed to a single factor and reported as such. However, despite the wealth of clinical experience internationally available, information regarding certain simple considerations is still lacking. Garnering information on all the factors that could possibly influence the outcome has become more difficult due to a (fortunate decrease in the incidence of deep sternal wound infection. If more insight is to be gained from fewer clinical cases, then various potentially confounding factors should be fully disclosed before complications can be attributed to the technique itself or improvements to negative-pressure wound therapy for deep sternal wound infection can be accepted as evidence-based and the guidelines for its use adapted. The authors propose the adoption of a simple checklist in such cases.

  15. Can single use negative pressure wound therapy be an alternative method to manage keloid scarring? A preliminary report of a clinical and ultrasound/colour-power-doppler study.

    Science.gov (United States)

    Fraccalvieri, Marco; Sarno, Antonino; Gasperini, Stefano; Zingarelli, Enrico; Fava, Raffaella; Salomone, Marco; Bruschi, Stefano

    2013-06-01

    Keloid scarring represents a pathological healing where primary healing phenomenon is deviated from normal. Pico is a single use negative pressure wound therapy system originally introduced to manage open or just closed wounds. Pico dressing is made of silicone, and distributes an 80 mmHg negative pressure across wound bed. Combination of silicon layer and continuous compression could be a valid method to manage keloid scarring. Since November 2011, three patients were enrolled and evaluated before negative pressure treatment, at end of treatment (1 month) and 2 months later, through Vancouver Scar Scale (VSS), Visual Analog Scale (VAS) and a scoring system for itching. Ultrasound (US) and colour-power-doppler (CPD) examination was performed to evaluate thickness and vascularisation of the scar. One patient was discharged from study after 1 week. In last two patients, VSS, VAS and itching significantly improved after 1 month therapy and the results were stable after 2 months without any therapy. At end of therapy, the 'appearance of palisade vessels' disappeared in both cases at CPD exam; US showed a thickness reduction (average 43·8%). We propose a well-tolerated, non invasive treatment to manage keloid scarring. Prospective studies are necessary to investigate whether these preliminary observations are confirmed. © 2012 The Authors. International Wound Journal © 2012 John Wiley & Sons Ltd and Medicalhelplines.com Inc.

  16. A Risk Analysis Methodology to Address Human and Organizational Factors in Offshore Drilling Safety: With an Emphasis on Negative Pressure Test

    Science.gov (United States)

    Tabibzadeh, Maryam

    According to the final Presidential National Commission report on the BP Deepwater Horizon (DWH) blowout, there is need to "integrate more sophisticated risk assessment and risk management practices" in the oil industry. Reviewing the literature of the offshore drilling industry indicates that most of the developed risk analysis methodologies do not fully and more importantly, systematically address the contribution of Human and Organizational Factors (HOFs) in accident causation. This is while results of a comprehensive study, from 1988 to 2005, of more than 600 well-documented major failures in offshore structures show that approximately 80% of those failures were due to HOFs. In addition, lack of safety culture, as an issue related to HOFs, have been identified as a common contributing cause of many accidents in this industry. This dissertation introduces an integrated risk analysis methodology to systematically assess the critical role of human and organizational factors in offshore drilling safety. The proposed methodology in this research focuses on a specific procedure called Negative Pressure Test (NPT), as the primary method to ascertain well integrity during offshore drilling, and analyzes the contributing causes of misinterpreting such a critical test. In addition, the case study of the BP Deepwater Horizon accident and their conducted NPT is discussed. The risk analysis methodology in this dissertation consists of three different approaches and their integration constitutes the big picture of my whole methodology. The first approach is the comparative analysis of a "standard" NPT, which is proposed by the author, with the test conducted by the DWH crew. This analysis contributes to identifying the involved discrepancies between the two test procedures. The second approach is a conceptual risk assessment framework to analyze the causal factors of the identified mismatches in the previous step, as the main contributors of negative pressure test

  17. [Influence of different inner dressings in negative-pressure wound therapy on escharectomy wound of full-thickness burn rabbits].

    Science.gov (United States)

    Lin, J H; Chen, J; Xue, D J; Huang, W X; Su, G L

    2017-07-20

    Objective: To explore the influence of different inner dressings in negative-pressure wound therapy (NPWT) on escharectomy wound of full-thickness burn rabbits. Methods: Eighteen Japanese white rabbits were inflicted with full-thickness burn on unilateral back. They were divided into polymer dressing group (PD), biological dressing group (BD), and silver biological dressing group (SBD), according to the random number table, with 6 rabbits in each group. On 3 days post burn, the wounds were performed with escharectomy, and then wounds of rabbits in group PD were covered with polyurethane foam. Wounds of rabbits in group BD were covered with porcine acellular dermal matrix (ADM) and wounds of rabbits in group SBD were covered with silver porcine ADM. Then continuous NPWT was performed on rabbits of the three groups for 7 days. Immediately after surgery and on post surgery day (PSD) 7, general observation of wound was conducted and tissue around the wound was harvested for determination of dry to wet weight ratio. The content of bacteria was counted and the content of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 in wound was determined by enzyme-linked immunosorbent assay. Fibroblasts in wound were counted after Masson staining and number of microvessels was counted after CD31 antibody immunohistochemical staining. Data were processed with analysis of variance for repeated measurement, LSD- t test, paired samples t test, and Bonferroni correction. Results: (1) Immediately after surgery, there was no granulation tissue in basal wound of rabbits in the three groups, with rich blood supply and obvious edema. On PSD 7, much granulation tissue was found in basal wound of rabbits in the three groups, with no or mild edema and no obvious redness and swelling in wound edge. (2) There were no significant differences in dry to wet weight ratios of tissue around the wound among and within the three groups immediately after surgery and on PSD 7 (with F

  18. Control of abdominal and expiratory intercostal muscle activity during vomiting - Role of ventral respiratory group expiratory neurons

    Science.gov (United States)

    Miller, Alan D.; Tan, L. K.; Suzuki, Ichiro

    1987-01-01

    The role of ventral respiratory group (VRG) expiratory (E) neurons in the control of abdominal and internal intercostal muscle activity during vomiting was investigated in cats. Two series of experiments were performed: in one, the activity of VRG E neurons was recorded during fictive vomiting in cats that were decerebrated, paralyzed, and artificially ventilated; in the second, the abdominal muscle activity during vomiting was compared before and after sectioning the axons of descending VRG E neurons in decerebrate spontaneously breathing cats. The results show that about two-thirds of VRG E neurons that project at least as far caudally as the lower thoracic cord contribute to internal intercostal muscle activity during vomiting. The remaining VRG E neurons contribute to abdominal muscle activation. As shown by severing the axons of the VRG E neurons, other, as yet unidenified, inputs (either descending from the brain stem or arising from spinal reflexes) can also produce abdominal muscle activation.

  19. Parameters affecting the tidal volume during expiratory abdominal compression in patients with prolonged tracheostomy mechanical ventilation.

    Science.gov (United States)

    Morino, Akira; Shida, Masahiro; Tanaka, Masashi; Sato, Kimihiro; Seko, Toshiaki; Ito, Shunsuke; Ogawa, Shunichi; Takahashi, Naoaki

    2015-07-01

    [Purpose] The aim of this study was to clarify physical parameters affecting the tidal volume during expiratory abdominal compression in patients with prolonged tracheostomy mechanical ventilation. [Methods] Eighteen patients with prolonged mechanical ventilation were included in this study. Expiratory abdominal compression was performed on patients lying in a supine position. The abdomen above the navel was vertically compressed in synchronization with expiration and released with inspiration. We measured the tidal volume during expiratory abdominal compression. [Results] The mean tidal volume during expiratory abdominal compression was higher than that at rest (430.6 ± 127.1 mL vs. 344.0 ± 94.3 mL). The tidal volume during expiratory abdominal compression was correlated with weight, days of ventilator support, dynamic compliance and abdominal expansion. Stepwise multiple regression analysis revealed that weight (β = 0.499), dynamic compliance (β = 0.387), and abdominal expansion (β = 0.365) were factors contributing to the tidal volume during expiratory abdominal compression. [Conclusion] Expiratory abdominal compression increased the tidal volume in patients with prolonged tracheostomy mechanical ventilation. The tidal volume during expiratory abdominal compression was influenced by each of the pulmonary conditions and the physical characteristics.

  20. Abdominal wall reconstruction for large incisional hernia restores expiratory lung function

    DEFF Research Database (Denmark)

    Jensen, Kristian K; Backer, Vibeke; Jorgensen, Lars N

    2017-01-01

    (horizontal fascial defect width >10 cm) were compared with 18 patients with an intact abdominal wall who underwent colorectal resection. Patients were examined pre- and 1-year postoperatively. Examined measures included forced vital capacity, forced expiratory volume in first second, peak expiratory flow...

  1. Peripheral Microvascular Responses to Whole-Body Tilting, G(z) Centrifugation, and Lower Body Negative Pressure Stresses in Humans

    Science.gov (United States)

    Breit, G. A.; Watenpaugh, D. E.; Buckley, T. M.; Ballard, R. E.; Murthy, G.; Hargens, A. R.

    1994-01-01

    The response of the cutaneous microcirculation to orthostatic stress varies along the length of the body due to the interaction of central controls with regional responses to local blood pressure. We hypothesize that artificial orthostatic stresses such as Gz centrifugation and LBNP differ from whole-body tilting in terms of the distribution of microvascular blood flow. Cutaneous microvascular flows were measured by laser Doppler flowmetry at the neck, thigh, and leg of 15 normal subjects. Volunteers underwent stepwise head-up tilt (HUT) and short- and long-arm centrifugation protocols from supine control (0 Gz) to 0.2, 0.4, 0.6, 0.8, 1.0, 0.8, 0.6, 0.4, 0.2, and 0 Gz at the feet, for 30-s periods with 10-s transitions between levels. The same subjects underwent a corresponding supine LBNP protocol, up to 100 mmHg (in 20 mmHg increments) and back to zero pressure, which produced transmural pressure across blood vessels in the foot approximately equal to the HUT protocol. In general, application of all orthostatic stresses produced significant flow reductions in the lower body (p less than 0.05) and inconsistent changes in the neck. At low levels of each stress (0.4 Gz, 40 mmHg), LBNP generated the greatest relative reduction in flow in the lower body (-66.9+/-5.7%, thigh; -60.6 +/-5.7%, leg, mean +/- SE). HUT caused a less severe flow reduction than LBNP at the thigh and leg (-39.9 +/- 8.1% and -55.9+/-4.8%), while the effects induced by both forms of centrifugation were the least profound. Higher levels of each stress generally resulted in similar responses. These responses exhibit a consistent relationship to hypothesized changes in local microvascular transmural pressure, suggesting that myogenic and veno-arteriolar reflexes play a significant role in determining microvascular perfusion during orthostatic stress.

  2. Combined non-adaptive light and smell stimuli lowered blood pressure, reduced heart rate and reduced negative affect.

    Science.gov (United States)

    Dong, Shan; Jacob, Tim J C

    2016-03-15

    Bright light therapy has been shown to have a positive impact on seasonal affective disorder (SAD), depression and anxiety. Smell has also has been shown to have effects on mood, stress, anxiety and depression. The objective of this study was to investigate the effect of the combination of light and smell in a non-adaptive cycle. Human subjects were given smell (lemon, lavender or peppermint) and light stimuli in a triangular wave (60scycle) for 15min. Blood pressure and heart rate were monitored before and after each session for 5 consecutive days and a Profile of Mood States (POMS) test was administered before and after the sensory stimulation on days 1, 3 and 5. The light-smell stimulus lowered blood pressure, both systolic and diastolic, and reduced heart rate for all odours compared to control. Of the two sensory stimuli, the odour stimulus contributed most to this effect. The different aromas in the light-smell combinations could be distinguished by their different effects on the mood factors with lemon inducing the greatest mood changes in Dejection-Depression, Anger-Hostility, Tension-Anxiety. In conclusion, combined light and smell stimulation was effective in lowering blood pressure, reducing heart rate and improving mood. The combination was more effective than either smell or light stimuli alone, suggesting that a light-smell combination would be a more robust and efficacious alternative treatment for depression, anxiety and stress. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  3. First characterization of the expiratory flow increase technique: method development and results analysis

    International Nuclear Information System (INIS)

    Maréchal, L; Barthod, C; Jeulin, J C

    2009-01-01

    This study provides an important contribution to the definition of the expiratory flow increase technique (EFIT). So far, no measuring means were suited to assess the manual EFIT performed on infants. The proposed method aims at objectively defining the EFIT based on the quantification of pertinent cognitive parameters used by physiotherapists when practicing. We designed and realized customized instrumented gloves endowed with pressure and displacement sensors, and the associated electronics and software. This new system is specific to the manoeuvre, to the user and innocuous for the patient. Data were collected and analysed on infants with bronchiolitis managed by an expert physiotherapist. The analysis presented is realized on a group of seven subjects (mean age: 6.1 months, SD: 1.1; mean chest circumference: 44.8 cm, SD: 1.9). The results are consistent with the physiotherapist's tactility. In spite of inevitable variability due to measurements on infants, repeatable quantitative data could be reported regarding the manoeuvre characteristics: the magnitudes of displacements do not exceed 10 mm on both hands; the movement of the thoracic hand is more vertical than the movement of the abdominal hand; the maximum applied pressure with the thoracic hand is about twice higher than with the abdominal hand; the thrust of the manual compression lasts (590 ± 62) ms. Inter-operators measurements are in progress in order to generalize these results

  4. Theory of photostructural changes in glasses with negative-U centers: dependencies of steady-state photodarkening on gap-light intensity and frequency, pressure and temperature

    International Nuclear Information System (INIS)

    Klinger, M.I.

    2004-01-01

    A theory is presented of a mechanism for the photostructural changes observed in semiconducting glasses. The theory takes into account that in these materials negative-U centers are the basic charge carriers, and gap-light generated excited states of such centers are accompanied by metastable 'defects' in the original structure, which can be identified as the photostructural changes. The theory gives rise to a consistent interpretation, and some predictions, of dependencies of the steady-state photodarkening on gap-light intensity and frequency, pressure and temperature

  5. Effect of negative pressure therapy on repair of soft tissues of the lower extremities in patients with neuropathic and neuroischaemic forms of diabetic foot syndrome

    Directory of Open Access Journals (Sweden)

    Ekaterina Leonidovna Zaytseva

    2014-06-01

    Full Text Available AimTo evaluate the efficiency of topical negative pressure wound therapy (NPWT compared with standard therapy for the regeneration of the soft tissues of the lower extremities in patients with diabetic foot syndrome.Materials and MethodsThe effects of negative pressure therapy on the clinical (size, tissue oxygenation, histological (light microscopy and immunohistochemical (CD68, MMP-9, TIMP-1 aspects of repair of the soft tissue of the lower extremities in patients with diabetes mellitus were compared with those of standard treatment. Thirty-one patients with diabetic foot ulcers were included in the study from the moment of debridement until the plastic closure of the wound. During the perioperative period, 13 patients received NPWT (-90 to -120 mmHg and 18 patients received standard therapy.ResultsA reduction of the wound area (26.6%±17.2% and the depth of the defects (40.5%±25.6% were achieved with negative pressure therapy compared with baseline data. In the control group, the corresponding values were 25.3%±19.4% and 21.8%±21.6%, respectively. The results of transcutaneous oximetry showed a greater increase in the level of local hemodynamics in the study group (p <0.04. An important criterion for wound preparation for a plastic closure is filling it with granulation tissue by more than 75%. In the study group, 95% of patients had wounds filled with 89.9%±17% of abundant granulation tissue. The histological data of the study group show a significant reduction of oedema by 80% (p <0.05, improved extracellular matrix organization (p <0.05, 90% (p <0.05 dissolution of inflammatory infiltrate and the formation of healthy granulation tissue (p <0.05. Immunohistochemical analysis demonstrated a significant decrease in the number of macrophages in the dermis (CD68 expression (p <0.05. In both groups, the level of MMP-9 was decreased. However, the ratio of MMP-9:TIMP-1 was lower in the study group (p <0.05.ConclusionThe findings suggest that

  6. A compare between myocardial topical negative pressure levels of -25 mmHg and -50 mmHg in a porcine model

    DEFF Research Database (Denmark)

    Lindstedt, Sandra; Paulsson, Per; Mokhtari, Arash

    2008-01-01

    Topical negative pressure (TNP), widely used in wound therapy, is known to stimulate wound edge blood flow, granulation tissue formation, angiogenesis, and revascularization. We have previously shown that application of a TNP of -50 mmHg to the myocardium significantly increases microvascular blood...... flow in the underlying tissue. We have also shown that a myocardial TNP levels between -75 mmHg and -150 mmHg do not induce microvascular blood flow changes in the underlying myocardium. The present study was designed to elucidate the difference between -25 mmHg and -50 mmHg TNP on microvascular flow...

  7. Hemodynamic effects of pressures applied to the upper airway during sleep.

    Science.gov (United States)

    Eastwood, P R; Curran, A K; Smith, C A; Dempsey, J A

    2000-08-01

    The increase in systemic blood pressure after an obstructive apnea is due, in part, to sympathetically mediated vasoconstriction. We questioned whether upper airway (UA) receptors could contribute reflexly to this vasoconstriction. Four unanesthetized dogs were studied during wakefulness and non-rapid-eye-movement (NREM) sleep. The dogs breathed via a fenestrated tracheostomy tube sealed around the tracheal stoma. The snout was sealed with an airtight mask, thereby isolating the UA when the fenestration was closed and exposing the UA to negative inspiratory intrathoracic pressure when it was open. The blood pressure response to three UA perturbations was studied: 1) square-wave negative pressures sufficient to cause UA collapse with the fenestration closed during a mechanical hyperventilation-induced central apnea; 2) tracheal occlusion with the fenestration open vs. closed; and 3) high-frequency pressure oscillations (HFPO) with the fenestration closed. During NREM sleep, 1) blood pressure response to tracheal occlusion was similar with the fenestration open or closed; 2) collapsing the UA with negative pressures failed to alter blood pressure during a central apnea; and 3) application of HFPO to the UA during eupnea and resistive-loaded breaths increased heart rate and blood pressure. However, these changes were likely to be secondary to the effects of HFPO-induced reflex changes on prolonging expiratory time. These findings suggest that activation of UA pressure-sensitive receptors does not contribute directly to the pressor response associated with sleep-disordered breathing events.

  8. Hypercapnia attenuates inspiratory amplitude and expiratory time responsiveness to hypoxia in vagotomized and vagal-intact rats

    Science.gov (United States)

    Tin, Chung; Song, Gang; Poon, Chi-Sang

    2012-01-01

    A negative influence of central chemosensitivity on peripheral chemoreflex response has been demonstrated recently in a decerebrate-vagotomized rat preparation in situ with separate carotid body and brainstem perfusions. Here, we report similar negative influences of hypercapnia on the hypoxic respiratory response in anesthetized, spontaneously breathing rats before and after vagotomy and anesthetized, artificially ventilated rats after vagotomy. Baseline breathing patterns and responsiveness to hypercapnia and hypoxia varied widely between the three respiratory modes. Despite this, the responses in inspiratory amplitude and expiratory duration (and hence respiratory frequency and neural ventilation) to hypoxia varied inversely with the background CO2 level in all three groups. Results demonstrate a hypoadditive hypercapnic-hypoxic interaction in vivo that resembles the hypoadditive central-peripheral chemoreceptor interaction in situ for these respiratory variables in the rat, regardless of differences in vagal feedback, body temperature and ventilation method. These observations stand in contrast to previous reports of hyperadditive peripheral-central chemoreceptor interaction. PMID:22326640

  9. Abdominal Cavity Eventration Treated by Means of the "Open Abdomen" Technique Using the Negative Pressure Therapy System--Case Report and Literature Review.

    Science.gov (United States)

    Trzeciak, Piotr W; Porzeżyńska, Joanna; Ptasińska, Karolina; Walczak, Dominik A

    2015-11-01

    Wound dehiscence is a surgical complication in which the wound ruptures along the surgical suture with abdominal cavity bowel displacement. It is observed in 0.2-6% of operated patients. The extensive wound is a gateway for infection. Moreover, increased secretion of serous fluid induces a hygienic problem and may lead to secondary skin infections or bedsores. The negative pressure wound therapy (NPWT) system is an innovative therapeutic method. It perfectly executes the TIME strategy, receiving more and more recognition. The study presented a case of a 62-year old male patient after several consecutive wound dehiscence episodes who was primarily treated for rectal cancer by means of low anterior resection of the rectum. Due to acute respiratory insufficiency after several operations, wound necrosis with dehiscence was observed. Considering the high risk of perioperative death we abandoned surgical treatment and introduced conservative management using negative pressure wound therapy until the patient's health improved. Literature regarding the above-mentioned issue was also reviewed.

  10. The SNaP™ Wound Care System: A Case Series Using a Novel Ultraportable Negative Pressure Wound Therapy Device for the Treatment of Diabetic Lower Extremity Wounds

    Science.gov (United States)

    Lerman, Bruce; Oldenbrook, Leslie; Ryu, Justin; Fong, Kenton D.; Schubart, Peter J.

    2010-01-01

    Although there is significant evidence supporting the use of negative pressure wound therapy (NPWT) for the treatment of lower extremity diabetic ulcers, currently available electrically powered NPWT systems are not ideally suited for treating smaller diabetic foot ulcers. The Smart Negative Pressure (SNaP™) Wound Care System is a novel, ultraportable device that delivers NPWT without the use of an electrically powered pump. It was specifically designed to meet the wound care needs of patients with diabetes. The SNaP System is compact, silent, mobile, easy-to-use, and available off-the-shelf. It is fully disposable and may offer other important benefits over electrically powered systems to both the clinician and patient. We review the evidence for use of NPWT for the treatment of diabetic wounds and discuss the potential benefits of this new NPWT technology for patients with diabetes. We also present a case series of four difficult lower extremity diabetic ulcers that were successfully treated with the SNaP System. This study suggests that the SNaP System may be a useful addition to the armamentarium of the diabetic wound care clinician. PMID:20663444

  11. Stagnations of increasing trends in negative pressure with repeated cavitation in water/metal Berthelot tubes as a result of mechanical sealing

    International Nuclear Information System (INIS)

    Hiro, Kazuki; Ohde, Yoshihito; Tanzawa, Yasutoshi

    2003-01-01

    To investigate effects of mechanical sealing on negative pressures in water/metal tube Berthelot systems, trends in negative pressure are observed through runs of temperature cycles below 90 deg. C in two systems made of metals having small amounts of gas inclusions. The first system is a pre-degassed all-stainless-steel tube/plug system. The steel is a special product for vacuum engineering. The second is the same tube sealed with plugs made of silver solidified one-dimensionally in a vacuum furnace. A new type of trend, stagnation for intermediate cycles is found in both systems so long as sealing distortion of each plug is small in amount. The stagnation period for the first system is longer than that for the second one. A metallurgical mechanism of a gas-being-replenished crevice model is proposed: distorted parts of metals undergo heat-treatment during runs of temperature cycles, and the heat-treatment enhances the rates of impurity gas transports to crevices on the metal surface where cavitation occurs, and the transport causes the stagnation for cycles during which the rates are still high

  12. Use of a portable, single-use negative pressure wound therapy device in home care patients with low to moderately exuding wounds: a case series.

    Science.gov (United States)

    Hurd, Theresa; Trueman, Paul; Rossington, Alan

    2014-03-01

    Negative pressure wound therapy (NPWT) is widely used in the management of acute and chronic wounds. The purpose of this 8-week study was to evaluate outcomes of using a new canisterless, portable, single-use NPWT system in patients with wounds treated in a Canadian community healthcare setting. The device is designed to provide negative pressure at 80±20 mm Hg, 24 hours a day of continuous usage, for a maximum wear time of 7 days. Data on wound outcomes, including exudate levels, wound appearance, and wound area, were collected weekly by a Registered Nurse as part of routine practice. When treatment was discontinued, patients and nurses were asked to rate their satisfaction with the device. Data from patients who had used a conventional NPWT device to manage their wounds were retrospectively abstracted from their medical records. In the prospective study, conducted between October 2011 and July 2012, 326 patients (median age=61 years; range 17-91 years) with wounds of mixed etiology (53 pressure ulcers, 21 venous leg ulcers, 16 diabetic foot ulcers, and 15 traumatic and 221 surgical wounds) were treated for a maximum of 8 weeks with the portable NPWT device. The majority of patients (228 out of 326; 68%) achieved complete wound closure within 8 weeks of treatment. The Kaplan-Meier estimate of median time to healing of all wounds was 9 weeks. The majority of patients (318 patients, 97%) reported they were pleased or satisfied with the dressing performance. Nurses indicated satisfaction with the dressing performance for all but two patients (99%). The majority (89%) of patients managed with conventional NPWT (n=539) had an open surgical wound with moderate or high levels of exudate. Healing rates in the portable and conventional NPWT group were similar (10% to 11% per week). Portable, single-use NPWT has the potential to deliver good wound outcomes in community care settings and simplify the use of negative pressure for nurses and patients. Additional research is

  13. Explosion and fire in the expiratory limb of a Fisher and Paykel "three in one" respiratory care system.

    Science.gov (United States)

    Gowardman, J R; Moriarty, B

    1998-08-01

    We report an incident involving a Fisher and Paykel "There in One Respiratory Care System" (Fisher and Paykel Healthcare, Auckland, New Zealand). This is a new ventilator circuit designed to be adaptable to the needs of ventilator, intubated CPAP, and mask therapies. In this case the patient had received eight hours of CPAP therapy overnight, during which time the "Three in One" circuit had been broken down to the CPAP configuration. The expiratory limb heater element, normally disconnected, was inadvertently left connected to the heater base. Under the extreme conditions of heating under "no gas flow" mode, the heater element malfunctioned. As a result when the circuit was reconfigured to provide pressure-supported ventilation, in the high oxygen environment of the expiratory limb (FiO2 0.5), ignition and combustion of the respiratory circuit occurred. The case is reported because of the potentially serious consequences and because the incident prompted the manufacturer to redesign and change componentry in parts of the circuit implicated.

  14. The effects of smokeless cookstoves on peak expiratory flow rates in rural Honduras.

    Science.gov (United States)

    Rennert, W P; Porras Blanco, R M; Muniz, G B

    2015-09-01

    The use of biomass fuel for cooking in traditional cookstove designs negatively affects respiratory health of communities in developing countries. Indoor pollution affects particularly women and children, who are participating in food preparation. The effects of smokeless cookstove designs on indoor pollution are well documented, but few studies exist to assess the effects of improved stove designs on the respiratory health of community members. This study uses peak expiratory flow rate (PEFR) measurements in a before-and-after format to assess respiratory function of inhabitants of all 30 houses of Buenas Noches in central Honduras. PEFRs are measured before and 6 months after the installation of Justa stoves in people's homes. Health behaviors, respiratory symptoms and fire wood use are evaluated in a door-to-door survey format. A total of 137 eligible women and children between 6 and 14 years participated in the study. PEFR improved by 9.9-18.5% (P < 0.001) depending on the participants' exposure to indoor pollution. Health complaints like cough and behaviors like clinic visits did not change with the introduction of smokeless cookstove technology. Smokeless stoves improve respiratory health in an environment of high levels of indoor pollution. © The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Physiological and morphological determinants of maximal expiratory flow in chronic obstructive lung disease

    NARCIS (Netherlands)

    H.A.W.M. Tiddens (Harm); J.M. Bogaard (Jan); J.C. de Jongste (Johan); W.C.J. Hop (Wim); H.O. Coxson (Harvey); P.D. Pare

    1996-01-01

    textabstractMaximal expiratory flow in chronic obstructive pulmonary disease (COPD) could be reduced by three different mechanisms; loss of lung elastic recoil, decreased airway conductance upstream of flow-limiting segments; and increased collapsibility of airways.

  16. Management of the open abdomen using negative pressure wound therapy with instillation in severe abdominal sepsis: A review of 48 cases in Hospital Mexico, Costa Rica.

    Science.gov (United States)

    Sibaja, Pablo; Sanchez, Alfredo; Villegas, Guillermo; Apestegui, Alvaro; Mora, Esteban

    2017-01-01

    Despite the numerous advances in recent years, severe abdominal sepsis (with associated organ failure associated with infection) remains a serious, life-threatening condition with a high mortality rate. OA is a viable alternative to the previously used scheduled repeat laparotomy or continuous peritoneal lavage. The use of Negative Pressure Wound Therapy (NPWT) has been described as a successful method of management of the open abdomen. Adding instillation of saline solution to NPWT in a programmed and controlled manner, could offer the clinician an additional tool for the management of complex septic abdomen. To explore if the concept of active two-way therapy (Negative pressure wound therapy with instillation or NPWT-I) yields superior control of underlying, life-threatening abdominal infections and its effects on survival and morbidity in patients with severe abdominal sepsis when management with an open abdomen is required. A retrospective review of 48 patients with severe abdominal sepsis, who were managed with and open abdomen and NPWT-I was performed. NPWT-I was initiated utilizing the same parameters on all patients, this consisted of cycles of instillation of saline solution, which was removed through negative pressure after a short dwell period. We observed the effects on primary fascia closure rate, mortality, hospital and SICU length of stay and associated complications. Our patient group consisted of 20 (42%) males and 28 (58%) females. Average age was 48 years. Mortality in these patients was attributed to pulmonary embolism (n=1), acute renal failure (n=2) and cardiopulmonary arrest (n=1). Average total hospital stay was 24days, and stay in the SICU (n=26) averaged 7.5days. No acute complications related to the NPWT-I. All patients presenting with abdominal compartment syndrome resolved after initiation of the NPWT-I. A total of 46 patients (96%) patients achieved fascia closure after NPWT-I therapy after an average of 6days. Four patients (8%) died

  17. Decreased peak expiratory flow in pediatric passive smokers

    Directory of Open Access Journals (Sweden)

    Fitri Yanti

    2011-08-01

    Full Text Available Background Indonesia ranks fifth among countries with the highest aggregate levels of tobacco consumption in the world. Infants and children exposed to environmental tobacco smoke have increased rates of asthma, respiratory and ear infections, as well as reduced lung function. The effects of tobacco smoke exposure on lung function in children have been reported to be dependent on the source of smoke and the length and dose of exposure. Lung function may also be affected by a child’s gender and asthma status. Objective To compare peak expiratory flow (PEF in pediatric passive smokers to that of children not exposed to second hand smoke, and to define factors that may affect PEF in passive smokers. Methods In August 2009 we conducted a cross-sectional study at an elementary school in the Langkat district. Subjects were aged 6 to 12 years, and divided into two groups: passive smokers and those not exposed to secondhand smoke. Subjects’ PEFs were measured with a Mini-Wright peak flow meter. Measurements were performed in triplicate with the highest value recorded as the PEF. Demographic data including age, sex, weight, height, family income, parental education levels and occupations were obtained through questionnaires. Results Of the 170 participants, 100 were passive smokers and 70 were not exposed to secondhand smoke. Age distribution, weight and height were similar in both groups. We observed a significant difference in PEFs between the group of passive smokers and the group not exposed to secondhand smoke, 211.3 L/minute (SD 61.08 and 242.7 L/minute (SD 77.09, respectively (P < 0.005. The number of years of exposure to smoke (P = 0.079 and the number of cigarettes smoked daily in the household (P = 0.098 did not significantly influence PEF. Conclusion The PEF in pediatric passive smokers was significantly lower than that of children not exposed to secondhand smoke. PEF in passive smokers was not influenced by the number of years of smoke

  18. Espirometria de incentivo com pressão positiva expiratória é benéfica após revascularização miocardio Espirometría incentivada con presión positiva espiratoria es beneficiosa después de revascularización de miocardio Incentive spirometry with expiratory positive airway pressure brings benefits after myocardial revascularization

    Directory of Open Access Journals (Sweden)

    Glória Menz Ferreira

    2010-02-01

    protocolo de EI+EPAP se realizó en el período postoperatorio inmediato y durante 4 semanas más en domicilio. Dieciocho meses después de la CRM se evaluaron la fuerza de la musculatura respiratoria, la capacidad funcional, la función pulmonar, la calidad de vida y el nivel de actividad física. RESULTADOS: Después del test de caminata de seis minutos (TC6, el score para disnea (1,6 ± 0,6 vs 0,6 ± 0,3, P BACKGROUND: Patients undergoing coronary artery bypass graft (CABG surgery have higher risk to develop pulmonary complications (PCs such as atelectasis, pneumonia and pleural effusion. These complications could increase the length of hospital stay, resources utilization and also are associated with reduced quality of life and functional capacity a long term. OBJECTIVE: To test if the use of incentive spirometry (IS associated with expiratory positive airway pressure (EPAP, after CABG surgery improves dyspnea, effort perceived and quality of life 18 months after CABG. METHODS: Sixteen patients submitted to a CABG, were randomized to a control group (n=8 or IS+EPAP group (n=8. The protocol of IS+EPAP was applied in the immediate postoperative period and following for more 4 weeks in the patient's home. Eighteen months after CABG, the strength of the respiratory muscle, the functional capacity, the lung function, the quality of life and the level of physical activity were evaluated. RESULTS: After six minute walk test (6-MWT, the score of the dyspnea (1.6±0.6 vs 0.6±0.3, P<0.05 and the perceived effort (13.4±1.2 vs 9.1±0.7, P<0.05 were higher in the control group, when compared with the IS+EPAP group. In quality of life evaluation, the domain related to the physical aspects limitations was better in IS+EPAP group (93.7±4.1 vs 50±17, P<0.02. CONCLUSION: Patients that were submitted to IS+EPAP present reduction of dyspnea and lower effort sensation after the 6-MWT, and also a better quality of life 18 months after CABG.

  19. High and low negative pressure suction techniques in EUS-guided fine-needle tissue acquisition by using 25-gauge needles: a multicenter, prospective, randomized, controlled trial.

    Science.gov (United States)

    Kudo, Taiki; Kawakami, Hiroshi; Hayashi, Tsuyoshi; Yasuda, Ichiro; Mukai, Tsuyoshi; Inoue, Hiroyuki; Katanuma, Akio; Kawakubo, Kazumichi; Ishiwatari, Hirotoshi; Doi, Shinpei; Yamada, Reiko; Maguchi, Hiroyuki; Isayama, Hiroyuki; Mitsuhashi, Tomoko; Sakamoto, Naoya

    2014-12-01

    EUS-guided FNA (EUS-FNA) has a high diagnostic accuracy for pancreatic diseases. However, although most reports have typically focused on cytology, histological tissue quality has rarely been investigated. The effectiveness of EUS-FNA combined with high negative pressure (HNP) suction was recently indicated for tissue acquisition, but has not thus far been tested in a prospective, randomized clinical trial. To evaluate the adequacy of EUS-FNA with HNP for the histological diagnosis of pancreatic lesions by using 25-gauge needles. Prospective, single-blind, randomized, controlled crossover trial. Seven tertiary referral centers. Patients referred for EUS-FNA of pancreatic solid lesions. From July 2011 to April 2012, 90 patients underwent EUS-FNA of pancreatic solid masses by using normal negative pressure (NNP) and HNP with 2 respective passes. The order of the passes was randomized, and the sample adequacy, quality, and histology were evaluated by a single expert pathologist. EUS-FNA by using NNP and HNP. The adequacy of tissue acquisition and the accuracy of histological diagnoses made by using the EUS-FNA technique with HNP. We found that 72.2% (65/90) and 90% (81/90) of the specimens obtained using NNP and HNP, respectively, were adequate for histological diagnosis (P = .0003, McNemar test). For 73.3% (66/90) and 82.2% (74/90) of the specimens obtained by using NNP and HNP, respectively, an accurate diagnosis was achieved (P = .06, McNemar test). Pancreatitis developed in 1 patient after this procedure, which subsided with conservative therapy. This was a single-blinded, crossover study. Biopsy procedures that combine the EUS-FNA with HNP techniques are superior to EUS-FNA with NNP procedures for tissue acquisition. ( UMIN000005939.). Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  20. Foliar δ13C Showed No Altitudinal Trend in an Arid Region and Atmospheric Pressure Exerted a Negative Effect on Plant δ13C.

    Science.gov (United States)

    Chen, Zixun; Wang, Guoan; Jia, Yufu

    2017-01-01

    Previous studies have suggested foliar δ 13 C generally increases with altitude. However, some observations reported no changes or even decreased trends in foliar δ 13 C. We noted that all the studies in which δ 13 C increased with elevation were conducted in the human regions, whereas those investigations in which δ 13 C did not vary or decreased were conducted in areas with water stress. Thus, we proposed that the pattern of increasing δ 13 C with elevation is not a general one, and that δ 13 C may remain unchanged or decrease in plants grown in arid environments. To test the hypothesis, we sampled plants along altitude gradients on the shady and sunny slopes of Mount Tianshan characterized by arid and semiarid climates. The measurements of foliar δ 13 C showed no altitudinal trends for the plants grown on either of the slopes. Therefore, this study supported our hypothesis. In addition, the present study addressed the effect of atmospheric pressure on plant δ 13 C by accounting for the effects of temperature and precipitation on δ 13 C. This study found that the residual foliar δ 13 C increased with increasing altitude, suggesting that atmospheric pressure played a negative role in foliar δ 13 C.

  1. Incisional Negative Pressure Wound Therapy

    DEFF Research Database (Denmark)

    Hyldig, Nana; Vinter, Christina Anne; Bille, Camilla

    generator are used to allocate the participants into one of two groups (iNPWT vs. standard dressing), stratified by centre and type of CS. The study is conducted at five public hospitals located in three regions of Denmark. Interim analyses will be preformed along the trial using the group sequential method...... Therapy (iNPWT) applied prophylactically following caesarean section compared with standard postoperative dressings in obese women undergoing caesarean section. Method: This study is designed as an unblinded, pragmatic, parallel randomised multicenter trial, with a 1:1 allocation. A computer random number...

  2. [Relationship between expiratory muscle dysfunction and dynamic hyperinflation in advanced chronic obstructive pulmonary disease].

    Science.gov (United States)

    Mota, Susana; Güell, Rosa; Barreiro, Esther; Casan, Pere; Gea, Joaquim; Sanchis, Joaquín

    2009-10-01

    Dynamic hyperinflation (DH) and expiratory flow limitation (EFL) are physiologically linked and seem to be involved in the genesis of dyspnea and the quality of life (QL) impairment in chronic obstructive pulmonary disease (COPD). Advanced COPD patients often show expiratory muscles dysfunction that could be involved in DH development. Study the relationships between expiratory muscle dysfunction and DH, and their association with dyspnea and QL, in advanced COPD. In 25 patients we measured lung function, exercise capacity (incremental ergometry and walking test), EFL and end-expiratory lung volume (EELV) at rest and during exercise, respiratory muscles strength and endurance, dyspnea and QL (Saint George Respiratory Questionnaire, SGRQ). The patients (mean FEV(1)=31% predicted) showed a moderate decrease of respiratory muscles strength and endurance. Nineteen patients exhibited EFL at rest and 24 at 70% of maximal workload (W(max)). The EELV increased from rest to 70% W(max) (9% of predicted FVC). At 70% W(max) EELV correlated inversely with the EFL amount (rho=-0.42), the inspiratory and expiratory muscles endurance (rho=-0.43 and -0.42 respectively) and y VO(2max) (rho=-0.52). The EELV increase from resting to 70% W(max) correlated with dyspnea (rho=0.53) and the amount of EFL at 70%W(max) with the activity score of SGRQ. The FEV(1,) expiratory muscles endurance and LFE amount were independent predictors of EELV at 70% W(max). In advanced COPD a poorer expiratory muscles endurance is related with higher DH during exercise (and lower EFL), which is correlated with higher dyspnea and worse QL.

  3. High positive end-expiratory pressure levels promote bacterial translocation in experimental pneumonia

    NARCIS (Netherlands)

    Lachmann, Robert A.; van Kaam, Anton H.; Haitsma, Jack J.; Lachmann, Burkhard

    2007-01-01

    A previous study in piglets with experimental pneumonia showed that reducing atelectasis by means of open lung ventilation attenuated bacterial translocation compared to conventional ventilation settings. This study examined the effect of open lung ventilation with higher than necessary positive

  4. Effects of expiratory muscle training on the frail elderly's respiratory function.

    Science.gov (United States)

    Chigira, Yusuke; Miyazaki, Ikuri; Izumi, Masataka; Oda, Takahiro

    2018-02-01

    [Purpose] The present study examined the effects of expiratory muscle training on elderly day care service users, who had been classified into Care Grades 1 and 2 based on Japan's long-term care insurance system. [Subjects and Methods] Intervention was provided for 29 Care Grade 1 or 2 day care service users. During intervention, expiratory muscle training was performed by slowly expiring using the abdominal muscles and a device after maximal inspiration. Each intervention session lasted for approximately 10 minutes, and 2 sessions were held weekly for 3 months to compare respiratory function test values before and after intervention. [Results] The results were favorable. The vital capacity (VC) and peak expiratory flow (PEF) significantly varied between before and after intervention. [Conclusion] Expiratory muscle training generally improved their respiratory function, particularly their VC and PEF that significantly varied between before and after intervention. As both of these items influence the cough capacity, they may be key to the prevention of aspiration pneumonia. Expiratory muscle training may also contribute to activities of daily living (ADL) and the quality of life, and it is expected to play an important role in rehabilitation as a field of preventive medicine.

  5. Changes in Cross-Sectional Area and Transverse Diameter of the Heart on Inspiratory and Expiratory Chest CT: Correlation with Changes in Lung Size and Influence on Cardiothoracic Ratio Measurement.

    Directory of Open Access Journals (Sweden)

    Hayato Tomita

    Full Text Available The aim of this study was to investigate physiological changes in cardiac area and diameters between inspiratory and expiratory chest computed tomography (CT, and to assess their correlation with lung size change and influence on cardiothoracic ratio (CTR measurements.The institutional review board of our institution approved this study, and informed consent was waived. Forty-three subjects underwent inspiratory and expiratory chest CT as part of routine clinical care. On both inspiratory and expiratory scans, lung volumes and maximum lung diameters (transverse and vertical directions were measured. The maximum cardiac cross-sectional area (CSA and the maximum transverse cardiac diameter were measured on both scans, and the CT-based CTR was calculated. Changes in the lung and cardiac measurements were expressed as the expiratory/inspiratory (E/I ratios. Comparisons between inspiratory and expiratory measurements were made by the Wilcoxon signed-rank test. Correlations between the E/I ratios of lung and heart measurements were evaluated by Spearman's rank correlation analysis.Cardiac CSA and transverse cardiac diameter was significantly larger on expiratory than on inspiratory CT (p < 0.0001. Significant negative correlations were found between the E/I ratios of these cardiac measurements and the E/I ratios of lung volume and vertical lung diameter (p < 0.01. CT-based CTR was significantly larger on expiration than on inspiration (p < 0.0001.Heart size on chest CT depends on the phase of ventilation, and is correlated with changes in lung volume and craniocaudal lung diameter. The CTR is also significantly influenced by ventilation.

  6. Effect of variable circuit flow rate during the expiratory phase on CO2 elimination

    Directory of Open Access Journals (Sweden)

    Keszler PA

    2012-05-01

    Full Text Available Peter A Keszler,1 Pankaj Nagaraj,1 Kabir Abubakar,1 Martin Keszler21Georgetown University, Washington, DC, USA; Georgetown University Hospital, Washington, DC, USA; 2Brown University, Women and Infants Hospital of Rhode Island, Providence, RI, USABackground: Some continuous flow infant ventilators allow independent setting of inspiratory and expiratory circuit flow rate. In the Dräger Babylog 8000+ ventilator, this is called "variable inspiratory, variable expiratory flow" (VIVE. Some clinicians believe that lower expiratory flow decreases expiratory resistance. The minimum expiratory flow rate needed to avoid re-breathing of carbon dioxide (CO2 has never been established.Objective: We sought to determine if re-breathing becomes evident at the lowest possible expiratory flow rate setting of 1 L/min.Design/methods: We conducted a bench study using end-tidal CO2 (ETCO2 measurement and a 45 mL (90 mL for the "term" model test lung pre-filled with 100% CO2. We previously showed that the time needed for ETCO2 to be eliminated from the lung is a highly reproducible indicator of efficiency of ventilation. Re-breathing would thus be identified by an increase in the time required for the CO2 to be washed out from the test lung at stable settings of rate and tidal volume (VT. Using a Babylog 8000+ ventilator in volume guarantee mode with VIVE and a standard ventilator circuit, we tested the effect of decreasing expiratory flow rate under conditions simulating three sizes of patients: extremely low birth weight infant, wt = 600 g (VT = 3.5 mL, respiratory rate (RR = 60 breaths min-1, minute ventilation (MV = 210 mL/min, expiratory flow rate = 3 L/min, 2 L/min, and 1 L/min, very low birth weight infant, wt = 1.5 kg (VT= 7 mL, RR = 60 breaths min-1, MV = 420 mL/min, expiratory flow rate = 4 L/min, 3 L/min, 2 L/min, and 1 L/min, and term infant, wt = 3.6 kg (VT = 16 mL, RR = 60 breaths min-1, MV = 960 mL/min, expiratory flow rate = 5 L/min, 4 L/min, 3 L

  7. Fluid Redistribution and Heart Rate in Humans During Whole-Body Tilting, G(z) Centrifugation, and Lower Body Negative Pressure

    Science.gov (United States)

    Watenpaugh, D. E.; Breit, G. A.; Ballard, R. E.; Murthy, G.; Hargens, A. R.

    1994-01-01

    Gravity creates blood pressure gradients which redistribute body fluids towards the feet. Positive G(z) centrifugation and lower body negative pressure (LBNP) have been proposed to simulate these and other effects of gravity during long-term existence in microgravity. We hypothesized that the magnitude of upper-to-lower body fluid redistribution would increase according to the following order: short-arm centrifugation (SAC), long-arm centrifugation (LAC), head-up tilt (HUT), and LBNP. To test this hypothesis, we employed strain gauge plethysmography of the neck, thigh and calf during HUT and supine SAC and LAC up to lG(z) at the feet, and during supine LBNP to 100 mm Hg. Supine 100 mm Hg LBNP generates footward force and produces transmural blood pressures in the foot approximately equal to 1 G(z) (90 deg) HUT. Heart rate was measured via cardiotachometry. Control measurements were made while supine. SAC and LAC elicited similar increases in thigh volume at 1 G(z) (2.3 +/- 0.4 and 2.1 +/- 0.1%, respectively; mean +/- se, n greater than or equal to 7). At 100 mm Hg LBNP, thigh volume increased (3.4 +/- 0.3%) significantly more than during l G(z) centrifugation (p less than 0.05). Surprisingly, due to a paradoxical 0.6% reduction of thigh volume between 0.8 and 1.0 G(z) HUT, thigh volume was increased only 0.6 +/- 0.3% at 1 G(z) HUT. The calf demonstrated similar, although less definitive, responses to the various gravitational stimuli. Neck volume tended to decrease less during HUT than during the other stimuli. Heart rate increased similarly during HUT (18 +/- 2 beats/min) and LAC (12 +/- 2 beats/min), and exhibited still greater elevation during LBNP (29 +/- 4 beats/min), yet did not increase during SAC. These results suggest upright posture activates mechanisms that counteract footward fluid redistribution which are not activated during supine applications of simulated gravity. LAC more closely approximated effects of normal gravity (HUT) than LBNP. Therefore

  8. Negative Pressure Wound Therapy Literature Review of Efficacy, Cost Effectiveness, and Impact on Patients' Quality of Life in Chronic Wound Management and Its Implementation in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Diaa Othman

    2012-01-01

    Full Text Available This is a paper reviewing the National Health Service (NHS agenda in relation to the use of Negative Pressure Wound Therapy (NPWT in chronic wound management and assesses the evidence behind it, its cost effectiveness and the outcome it has on patients’ satisfaction and life style. Multiple studies over the last 10 years looking at clinical efficacy of NPWT with its cost effectiveness and the implementation of this service in the UK were reviewed. NPWT has showed a reasonable body of evidence to support its usage in chronic wounds with potential positive outcomes on finance and patients’ satisfaction. However, the NHS system shows significant variations in the availability and implementation of this useful tool, depending on care providers and resources availabilities. The paper concluded that the NPWT can be a useful source of cutting down costs of chronic wound managements and saving money by its effect on expediting wound healing, which can address a part of the financial crises facing the NHS, however, has to be considered according to specific case needs. There should also be a national standard for the availability and indication of this tool to assure equal opportunities for different patients in different areas in the country.

  9. Silver from polyurethane dressing is delivered by gradient to exudate, tissue, and serum of patients undergoing negative-pressure wound treatment.

    Science.gov (United States)

    Abarca-Buis, René F; Munguía, Nadia M; Gonzalez, Juan Manuel Melchor; Solís-Arrieta, Lilia; y Osorio, Liliana Saldivar; Krötzsch, Edgar

    2014-04-01

    This study aimed to evaluate the distribution and concentration of silver eluted from silver-coated polyurethane dressing (V.A.C. GranuFoam Silver Dressing; KCI, San Antonio, Texas) in vitro and in patients undergoing negative-pressure wound therapy (NPWT). This was a descriptive study of the effect of silver-coated polyurethane dressing in patients undergoing NPWT. Six patients with infected wounds undergoing NPWT using silver-coated polyurethane dressing. To evaluate silver release in vitro, the authors soaked dressing fragments in water and human serum for different lengths of time and performed atomic absorption spectroscopy. For patient evaluation, the authors obtained exudate, serum, and wound tissue at different time points from 6 patients undergoing NPWT and measured silver levels by atomic absorption and dispersed x-ray spectroscopy. Silver from the dressing was immediately released in vitro at a rate 3 times greater in serum than in water. In vivo, silver was delivered to wound exudate at rates 102 to 104 times greater than in corresponding serum. Few surface silver deposits were detected in treated tissue. The high concentration of silver found in wound exudate reflects not only the affinity for silver in serum components and wound fluids, but also that most silver ions are not distributed systemically in the patient; instead, they are transported by the vacuum created by therapy.

  10. Laparostomy management using the ABThera™ open abdomen negative pressure therapy system in a grade IV open abdomen secondary to acute pancreatitis.

    Science.gov (United States)

    Fitzgerald, James E F; Gupta, Shradha; Masterson, Sarah; Sigurdsson, Helgi H

    2013-04-01

    Wound control in laparostomy for the treatment of intra-abdominal hypertension remains challenging and numerous techniques have been described. We report the first UK experience with a new commercially available device specifically designed to facilitate management of the open abdomen. A 44-year-old gentleman presented with a 3-day history of constant severe epigastric pain and associated vomiting. Amylase was markedly elevated and he was admitted for supportive management of pancreatitis, with subsequent transfer to intensive care due to severe systemic inflammatory syndrome. The patient decompensated, developing intra-abdominal hypertension with renal and respiratory failure. This was successfully managed by performing a laparostomy and using an ABThera™ Open Abdomen Negative Pressure Therapy System (KCI, San Antonio, TX). We describe its use to facilitate wound control, including enteroatmospheric fistula, allowing granulation and eventual restoration of gastrointestinal continuity 383-days after admission. We found the ABThera™ System proved to be a useful treatment adjunct, protecting intra-abdominal contents while removing large volumes of exudate and infected material from within the abdominal cavity. Complex cases such as this remain infrequent and this article provides a summary of our experience, including a review of indications for laparostomy and the underlying basic science in this difficult area. © 2012 The Authors. International Wound Journal © 2012 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  11. Ultra pressure liquid chromatography-negative electrospray ionization mass spectrometry determination of twelve halobenzoquinones at ng/L levels in drinking water.

    Science.gov (United States)

    Huang, Rongfu; Wang, Wei; Qian, Yichao; Boyd, Jessica M; Zhao, Yuli; Li, Xing-Fang

    2013-05-07

    We report here the characterization of twelve halobenzoquinones (HBQs) using electrospray ionization (ESI) high resolution quadrupole time-of-flight mass spectrometry. The high resolution negative ESI spectra of the twelve HBQs formed two parent ions, [M + H(+) + 2e(-)], and the radical M(-•). The intensities of these two parent ions are dependent on their chemical structures and on instrumental parameters such as the source temperature and flow rate. The characteristic ions of the HBQs were used to develop an ultra pressure liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. At the UPLC flow rate (400 μL/min) and under the optimized ESI conditions, eleven HBQs showed the stable and abundant transitions [M + H(+) + 2e(-)] → X(-) (X(-) representing Cl(-), Br(-), or I(-)), while dibromo-dimethyl-benzoquinone (DBDMBQ) showed only the transition of M(-•) → Br(-). The UPLC efficiently separates all HBQs including some HBQ isomers, while the MS/MS offers exquisite limits of detection (LODs) at subng/mL levels for all HBQs except DBDMBQ. Combined with solid phase extraction (SPE), the method LOD is down to ng/L. The results from analysis of authentic samples demonstrated that the SPE-UPLC-MS/MS method is reliable, fast, and sensitive for the identification and quantification of the twelve HBQs in drinking water.

  12. Negative pressure wound therapy literature review of efficacy, cost effectiveness, and impact on patients' quality of life in chronic wound management and its implementation in the United kingdom.

    Science.gov (United States)

    Othman, Diaa

    2012-01-01

    This is a paper reviewing the National Health Service (NHS) agenda in relation to the use of Negative Pressure Wound Therapy (NPWT) in chronic wound management and assesses the evidence behind it, its cost effectiveness and the outcome it has on patients' satisfaction and life style. Multiple studies over the last 10 years looking at clinical efficacy of NPWT with its cost effectiveness and the implementation of this service in the UK were reviewed. NPWT has showed a reasonable body of evidence to support its usage in chronic wounds with potential positive outcomes on finance and patients' satisfaction. However, the NHS system shows significant variations in the availability and implementation of this useful tool, depending on care providers and resources availabilities. The paper concluded that the NPWT can be a useful source of cutting down costs of chronic wound managements and saving money by its effect on expediting wound healing, which can address a part of the financial crises facing the NHS, however, has to be considered according to specific case needs. There should also be a national standard for the availability and indication of this tool to assure equal opportunities for different patients in different areas in the country.

  13. The Effect of Negative Pressure Wound Therapy With Antiseptic Instillation on Biofilm Formation in a Porcine Model of Infected Spinal Instrumentation.

    Science.gov (United States)

    Singh, Devinder P; Gowda, Arvind U; Chopra, Karan; Tholen, Michael; Chang, Sarah; Mavrophilipos, Vasilios; Semsarzadeh, Nina; Rasko, Yvonne; Holton Iii, Luther

    2017-06-01

    This study evaluates the effect of negative pressure wound therapy with antiseptic instillation (NPWTi) in the clearance of infection and biofilm formation in an in vivo model of infected spinal implants compared to traditional treatment modalities. Five pigs underwent titanium rod implantation of their spinous processes followed by injection of 1 x 106 CFUs/100μL of methicillin-resistant Staphylococcus aureus through the fascia at each site. At 1 week postoperatively, an experimental arm of 3 pigs received NPWTi, and a control arm of 2 pigs received wet-to-dry dressings. The persistence of local infection in the experimental group was compared to the control group using tissue cultures. Biofilm development on spinal implants was evaluated using scanning electron microscopy. Mean bacterial count showed a statistical difference between the experimental and the control groups (P < .05). Scanning electron microscopy revealed the presence of uniform biofilm formation across the surface of control group instrumentation, whereas the experimental group showed interrupted areas between biofilm formations. The authors concluded that NPWTi is associated with decreased bacterial load and biofilm formation compared to wet-to-dry dressings in an in vivo porcine model of infected spinal instrumentation.

  14. Combined use of fenestrated-type artificial dermis and topical negative pressure wound therapy for the venous leg ulcer of a rheumatoid arthritis patient.

    Science.gov (United States)

    Morimoto, Naoki; Kuro, Atsuyuki; Yamauchi, Takashi; Horiuchi, Ai; Kakudo, Natsuko; Sakamoto, Michiharu; Suzuki, Kenji; Kusumoto, Kenji

    2016-02-01

    We report a case of circumferential venous leg ulcer in a rheumatoid arthritis patient. Mesh skin grafting was performed in another hospital, but the graft failed and the patient was referred to our hospital. This ulcer was treated by the combination therapy of a fenestrated-type artificial dermis with negative pressure wound therapy (NPWT) and secondary mesh grafting using our 'grip tape technique'. NPWT was started at -100 mmHg and continued until the formation of dermis-like tissue. A section stained using haematoxylin and eosin and an anti-αSMA (α smooth muscle actin) immunohistological section of the biopsy from dermis-like tissue showed an abundant infiltration of fibroblasts and capillary formation beneath the fenestration of the silicone sheet. Threefold mesh skin grafting was subsequently performed and it was taken up completely. The fenestrated-type artificial dermis in combination with NPWT produced good results without infection in the treatment of complex wounds. In addition, our 'grip tape technique' was useful to apply polyurethane foam to the entire surface of the lower leg. © 2015 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  15. Negative Pressure Wound Therapy Literature Review of Efficacy, Cost Effectiveness, and Impact on Patients' Quality of Life in Chronic Wound Management and Its Implementation in the United Kingdom

    Science.gov (United States)

    Othman, Diaa

    2012-01-01

    This is a paper reviewing the National Health Service (NHS) agenda in relation to the use of Negative Pressure Wound Therapy (NPWT) in chronic wound management and assesses the evidence behind it, its cost effectiveness and the outcome it has on patients' satisfaction and life style. Multiple studies over the last 10 years looking at clinical efficacy of NPWT with its cost effectiveness and the implementation of this service in the UK were reviewed. NPWT has showed a reasonable body of evidence to support its usage in chronic wounds with potential positive outcomes on finance and patients' satisfaction. However, the NHS system shows significant variations in the availability and implementation of this useful tool, depending on care providers and resources availabilities. The paper concluded that the NPWT can be a useful source of cutting down costs of chronic wound managements and saving money by its effect on expediting wound healing, which can address a part of the financial crises facing the NHS, however, has to be considered according to specific case needs. There should also be a national standard for the availability and indication of this tool to assure equal opportunities for different patients in different areas in the country. PMID:22701169

  16. Negative pressure wound therapy using a portable single-use device for free skin grafts on the distal extremity in seven dogs.

    Science.gov (United States)

    Miller, A J; Cashmore, R G; Marchevsky, A M; Havlicek, M; Brown, P M; Fearnside, S M

    2016-09-01

    Retrospective study to describe clinical experience with a portable single-use negative pressure wound therapy device after application of full-thickness meshed skin grafts to wounds on the distal extremities of seven dogs. Seven dogs were treated with portable NPWT after receiving skin grafts; six as the result of tumour resection and one for traumatic injury. Medical records were reviewed and data recorded on patient signalment, cause and location of wound, surgical technique, application and maintenance of portable NPWT, graft survival and outcome, and complications encountered with the system. NPWT was provided for between 4 and 7 days. Five patients were discharged from hospital during the treatment period. Application and maintenance of the portable device was technically easy and no major complications were encountered. Minor complications consisted of fluid accumulation in the evacuation tubing. All dogs achieved 100% graft survival. Application and maintenance of the portable device was technically straightforward. All dogs receiving portable NPWT after transfer of a free skin graft to the distal extremity had a successful outcome. © 2016 Australian Veterinary Association.

  17. Negative pressure wound therapy, silver coated foam dressing and conventional bandages in open wound treatment in dogs. A retrospective comparison of 50 paired cases.

    Science.gov (United States)

    Nolff, M C; Fehr, M; Bolling, A; Dening, R; Kramer, S; Reese, S; Meyer-Lindenberg, A

    2015-01-01

    To evaluate negative pressure wound therapy (NPWT) for treatment of complicated wounds in dogs. Retrospective multicentre study. Dogs (n = 50) undergoing open wound treatment were classified according to treatment method used: bandage (Group A, n = 7), NPWT (Group B, n = 18), and foam dressing (Group C, n = 25). Pairs of patients matched based on wound conformation, localization, and underlying cause were compared between Group A and C (n = 7 pairs) and between groups B and C (n = 18 pairs) in terms of duration of previous treatment, time to closure, and complications. Signalment, antibiotic medications, antiseptic treatment, and bacterial status of wounds were comparable between groups. The duration of previous treatment was significantly higher in patients assigned to Group B (p = 0.04) compared to Group C, while no significant difference was found between groups A and B. Total time to wound closure was significantly shorter in Group C compared to Group A (p = 0.02) and in Group B compared to Group C (p = 0.003). Wounds treated with NPWT suffered significantly less complications (p = 0.008) and were significantly less septic during treatment (p = 0.016) than wounds treated with a foam dressing. This study shows that time to healing was halved in NPWT treated patients compared to foam dressing treated patients, which in turn healed faster than patients treated with conventional bandage, underlining the value of NPWT therapy for the treatment of complicated wounds.

  18. Clinical Experience With the Use of Negative Pressure Wound Therapy Combined With a Silver-impregnated Dressing in Mixed Wounds: A Retrospective Study of 50 Cases.

    Science.gov (United States)

    Bukovcan, Peter; Koller, Jan; Hajská, Marianna; Záhorec, Peter

    2016-08-01

    Although negative pressure wound therapy (NPWT) has been used for more than 20 years, as far as the authors are aware, there is little research aimed at the evaluation of the combination of NPWT with a silver-impregnated dressing. The aim of this study was to examine the effect, efficacy, and safety of NPWT in conjunction with a silver-impregnated dressing. The authors used a retrospective study of 54 acute and chronic wounds treated in 50 patients over a 2-year period. Demographic data, wound characterizations, wound cultures before and after NPWT, the duration of NPWT and number of sponge changes for each patient, the types of surgical procedures used for wound closure following NPWT, and the healing time and length of hospital stays were recorded. In 26 wounds, deep structures (ie, bones and tendons) were exposed. The mean NPWT duration was 9.2 days. Mean healing time was 16 days. There was a statistically significant decrease in the pathogenic microbial strains after NPWT treatment combined with the silver-impregnated dressing (paired t test; P = 0.0038). The shift from complicated to easier surgical wound-closure procedures was observed. According to all results obtained, described, and discussed, the authors consider the use of a nonadherent silver-impregnated dressing in conjunction with NPWT to be beneficial and efficacious. No adverse events or reactions related to the silver-impregnated contact layer used during NPWT have been observed in the patients, which confirmed the safety of this method.

  19. Negative pressure wound therapy applied before and after split-thickness skin graft helps healing of Fournier gangrene: a case report (CARE-Compliant).

    Science.gov (United States)

    Ye, Junna; Xie, Ting; Wu, Minjie; Ni, Pengwen; Lu, Shuliang

    2015-02-01

    Fournier gangrene is a rare but highly infectious disease characterized by fulminant necrotizing fasciitis involving the genital and perineal regions. Negative pressure wound therapy (NPWT; KCI USA Inc, San Antonio, TX) is a widely adopted technique in many clinical settings. Nevertheless, its application and effect in the treatment of Fournier gangrene are unclear. A 47-year-old male patient was admitted with an anal abscess followed by a spread of the infection to the scrotum, which was caused by Pseudomonas aeruginosa. NPWT was applied on the surface of the scrotal area and continued for 10 days. A split-thickness skin graft from the scalp was then grafted to the wound, after which, NPWT utilizing gauze sealed with an occlusive dressing and connected to a wall suction was employed for 7 days to secure the skin graft. At discharge, the percentage of the grafted skin alive on the scrotum was 98%. The wound beside the anus had decreased to 4 × 0.5 cm with a depth of 1 cm. Follow-up at the clinic 1 month later showed that both wounds had healed. The patient did not complain of any pain or bleeding, and was satisfied with the outcome. NPWT before and after split-thickness skin grafts is safe, well tolerated, and efficacious in the treatment of Fournier gangrene.

  20. Quantitative assessment of cross-sectional area of small pulmonary vessels in patients with COPD using inspiratory and expiratory MDCT

    Energy Technology Data Exchange (ETDEWEB)

    Matsuura, Yukiko, E-mail: matsuyuki_future@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Kawata, Naoko, E-mail: chumito_03@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Yanagawa, Noriyuki, E-mail: yanagawa@ho.chiba-u.ac.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sugiura, Toshihiko, E-mail: sugiura@js3.so-net.ne.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sakurai, Yoriko, E-mail: yoliri@nifty.com [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sato, Misuzu, E-mail: mis_misuzu@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Iesato, Ken, E-mail: iesato_k@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Terada, Jiro, E-mail: jirotera@chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sakao, Seiichiro, E-mail: sakao@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Tada, Yuji, E-mail: ytada@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Tanabe, Nobuhiro, E-mail: ntanabe@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Suzuki, Yoichi, E-mail: ysuzuki@faculty.chiba-u.jp [Department of public Health, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Tatsumi, Koichiro, E-mail: tatsumi@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan)

    2013-10-01

    Objectives: Structural and functional changes in pulmonary vessels are prevalent at the initial stages of chronic obstructive pulmonary disease (COPD). These vascular alterations can be assessed using cross-sectional area (CSA) of small pulmonary vessels. However, neither in non-COPD smokers nor in COPD patients it has been defined whether the structural changes of pulmonary vessels detected by paired inspiratory and expiratory CT scans are associated with emphysematous changes. We quantified the CSA and low attenuation area (LAA) and evaluated the changes in these parameters in the inspiratory and expiratory phases. Materials and methods: Fifty consecutive non-COPD smokers and COPD patients were subjected to multi detector-row CT and the percentage of vessels with a CSA less than 5 mm{sup 2} as well as the percentage LAA for total lung area (%CSA < 5, %LAA, respectively) were calculated. Results: The %CSA < 5 correlated negatively with %LAA. The %CSA < 5 was lower in COPD patients with emphysema as compared with non-COPD smokers and COPD patients with or without mild emphysema. In addition, the %CSA < 5 was lower in the no/mild emphysema subgroup as compared with non-COPD smokers. The respiratory phase change of %CSA < 5 in COPD patients was greater than that in non-COPD smokers. Conclusion: The percentage of small pulmonary vessels decreased as emphysematous changes increase, and this decrease was observed even in patients with no/mild emphysema. Furthermore, respiratory phase changes in CSA were higher in COPD patients than in non-COPD smokers.

  1. [Effect of intermittent negative pressure on matrix metalloproteinase 9 and transforming growth factor β of tendon-bone interface and joint fluid after reconstruction of anterior cruciate ligament in rabbits].

    Science.gov (United States)

    Sun, Z M; Dong, X H; Sun, Z J; Chang, Y H; Wu, X Y; Yi, Z; Ling, M

    2017-12-05

    Objective: To study the effect of intermittent negative pressure on matrix metalloproteinase 9 (MMP)-9 and transforming growth factor β of tendon-bone interface and joint fluid after reconstruction of anterior cruciate ligament in rabbits. Methods: A total of twenty-four New Zealand white rabbits were randomly selected hind leg of negative group, contralateral hind leg as control.Reconstruction of the anterior cruciate ligament was done by autogenous semitendinosus of rabbit.Joint of the negative pressure side placed drainage tube connecting the micro-negative pressure aspirator, and maintained an intermittent, low-intensity negative pressure.Control side placed ordinary drainage tube.Drainage tube of both sides was pulled out at the same time after 5 days.After 6 weeks, joint fluid and femur-ligament-tibia complex were obtained for study of expression of MMP-9 and TGF-β in joint fluid and tendon-bone interface. Result: Twenty-three rabbits were included in the study because of one rabbit joint infections.Detection of joint fluid showed that MMP-9 content is significantly lower in negative group than that in the control group, and the difference is statistically significant [(8.9±1.3) pg/L vs (12.3±1.8) pg/L ( P =0.002)]. TGF-β content is significantly higher in negative group in joint fluid than that in the control group, and the difference is statistically significant [(19.0±2.2) pg/L vs (15.2±1.4) pg/L ( P =0.000)]. Study of immunohistochemistry in tendon-bone interface found that expression of MMP-9 is lower in negative pressure group than that in the control group, and the difference is statistically significant ( P =0.000). TGF-β expression is significantly higher in negative group in tendon-bone interface than that in the control group, and the difference is statistically significant ( P =0.000). Conclusion: Intermittent negative pressure may reduce content of MMP-9 in joint fluid and expression of MMP-9 in tendon-bone interface, increase content of

  2. Carbon dioxide rebreathing caused by deformed silicon leaflet in the expiratory unidirectional valve

    Directory of Open Access Journals (Sweden)

    Arumugam Vasudevan

    2013-01-01

    Full Text Available Rebreathing of carbon dioxide caused by incompetent ′cage and disc′ unidirectional valves has been reported earlier. Some manufacturers have changed the design of unidirectional valves to ′flexible leaflets′. We report a series of cases where a deformed membrane leaflet in expiratory unidirectional valves led to rebreathing of carbon dioxide.

  3. Dead space and slope indices from the expiratory carbon dioxide tension-volume curve

    NARCIS (Netherlands)

    A.H. Kars (Alice); J.M. Bogaard (Jan); Th. Stijnen (Theo); J. de Vries; A.F.M. Verbraak (Anton); C. Hilvering

    1997-01-01

    textabstractThe slope of phase 3 and three noninvasively determined dead space estimates derived from the expiratory carbon dioxide tension (PCO2) versus volume curve, including the Bohr dead space (VD,Bohr), the Fowler dead space (VD,Fowler) and pre-interface expirate

  4. Relative impact of respiratory muscle activity on tidal flow and end expiratory volume in healthy neonates

    NARCIS (Netherlands)

    Hutten, Gerard J.; van Eykern, Leo A.; Latzin, Philipp; Kyburz, Manuela; van Aalderen, Wim M.; Frey, Urs

    2008-01-01

    Introduction: It has been suggested that infants dynamically regulate their tidal flow and end-expiratory volume level. The interaction between muscle activity, flow and lung volume in spontaneously sleeping neonates is poorly studied, since it requires the assessment of transcutaneous

  5. THE EFFECT OF SUBMAXIMAL INHALATION ON MEASURES DERIVED FROM FORCED EXPIRATORY SPIROMETRY

    Science.gov (United States)

    THE EFFECT OF SUBMAXIMAL INHALATION ON MEASURES DERIVED FROM FORCED EXPIRATORY SPIROMETRY. William F. McDonnell Human Studies Division, NHEERL, U.S. Environmental Protection Agency, RTP, NC 27711. Short-term exposure to ozone results in a neurally-mediated decrease in the ab...

  6. Modeling the Fate of Expiratory Aerosols and the Associated Infection Risk in an Aircraft Cabin Environment

    DEFF Research Database (Denmark)

    Wan, M.P.; To, G.N.S.; Chao, C.Y.H.

    2009-01-01

    The transport and deposition of polydispersed expiratory aerosols in an aircraft cabin were simulated using a Lagrangian-based model validated by experiments conducted in an aircraft cabin mockup. Infection risk by inhalation was estimated using the aerosol dispersion data and a model was developed...

  7. Effects of midline laparotomy on expiratory muscle activation in anesthetized dogs.

    Science.gov (United States)

    Farkas, G A; De Troyer, A

    1989-08-01

    Abdominal surgery has a marked inhibitory influence on the diaphragm, but its effect on the expiratory muscles is not known. Therefore, we have recorded the electromyograms of the triangularis sterni, abdominal external oblique, and transversus abdominis before and after a midline laparotomy in 10 anesthetized, spontaneously breathing dogs. Measurements were obtained during quiet breathing in the supine posture, during breathing against expiratory threshold loads, during head-up tilting, and during hyperoxic hypercapnia. Expiratory activation of the transversus abdominis in all conditions was considerably reduced after laparotomy. This reduction was real, as no change in the compound muscle action potential during single pulse stimulation was observed. In contrast, expiratory recruitment of either the triangularis sterni or the abdominal external oblique was maintained or increased. We therefore conclude that laparotomy inhibits not only activation of the diaphragm during inspiration but also activation of the transversus abdominis during expiration. Visceral afferents thus affect in concert the two respiratory muscles lining the peritoneum. The present findings also emphasize the important fact that the pattern of activation of a particular abdominal muscle is not necessarily representative of the entire abdominal musculature.

  8. Changes in forced expiratory volume in 1 second over time in COPD

    DEFF Research Database (Denmark)

    Vestbo, Jørgen; Edwards, Lisa D; Scanlon, Paul D

    2011-01-01

    A key feature of chronic obstructive pulmonary disease (COPD) is an accelerated rate of decline in forced expiratory volume in 1 second (FEV(1)), but data on the variability and determinants of this change in patients who have established disease are scarce....

  9. Exogenous stimuli and circadian peak expiratory flow variation in allergic asthmatic children

    NARCIS (Netherlands)

    Postma, DS; VanderHeide, S; DeReus, DM; Koeter, GH; VanAalderen, WMC; Meijer, G.

    The influence of exogenous factors in the home on the circadian variation of airway obstruction has not been fully assessed in children with asthma. The aim of the present study was to investigate the contribution of exogenous stimuli to the degree of peak expiratory flow (PEF) variability during 24

  10. Evidence-based recommendations for the use of Negative Pressure Wound Therapy in traumatic wounds and reconstructive surgery: steps towards an international consensus.

    Science.gov (United States)

    Krug, E; Berg, L; Lee, C; Hudson, D; Birke-Sorensen, H; Depoorter, M; Dunn, R; Jeffery, S; Duteille, F; Bruhin, A; Caravaggi, C; Chariker, M; Dowsett, C; Ferreira, F; Martínez, J M Francos; Grudzien, G; Ichioka, S; Ingemansson, R; Malmsjo, M; Rome, P; Vig, S; Runkel, N; Martin, R; Smith, J

    2011-02-01

    Negative pressure wound therapy (NPWT) has become widely adopted over the last 15 years and over 1000 peer reviewed publications are available describing its use. Despite this, there remains uncertainty regarding several aspects of usage. In order to respond to this gap a global expert panel was convened to develop evidence-based recommendations describing the use of NPWT. In this paper the results of the study of evidence in traumatic wounds (including soft tissue defects, open fractures and burns) and reconstructive procedures (including flaps and grafts) are reported. Evidence-based recommendations were obtained by a systematic review of the literature, grading of evidence, drafting of the recommendations by a global expert panel, followed by a formal consultative consensus development program in which 422 independent healthcare professionals were able to agree or disagree with the recommendations. The criteria for agreement were set at 80% approval. Evidence and recommendations were graded according to the SIGN (Scottish Intercollegiate Guidelines Network) classification system. Twelve recommendations were developed in total; 4 for soft tissue trauma and open fracture injuries, 1 for burn injuries, 3 for flaps and 4 for skin grafts. The present evidence base is strongest for the use of NPWT on skin grafts and weakest as a primary treatment for burns. In the consultative process, 11/12 of the proposed recommendations reached the 80% agreement threshold. The development of evidence-based recommendations for NPWT with direct validation from a large group of practicing clinicians offers a broader basis for consensus than work by an expert panel alone. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Does treatment of split-thickness skin grafts with negative-pressure wound therapy improve tissue markers of wound healing in a porcine experimental model?

    Science.gov (United States)

    Ward, Christopher; Ciraulo, David; Coulter, Michael; Desjardins, Steven; Liaw, Lucy; Peterson, Sarah

    2012-08-01

    Negative-pressure wound therapy (NPWT) has been used for to treat wounds for more than 15 years and, more recently, has been used to secure split-thickness skin grafts. There are some data to support this use of NPWT, but the actual mechanism by which NPWT speeds healing or improves skin graft take is not entirely known. The purpose of this project was to assess whether NPWT improved angiogenesis, wound healing, or graft survival when compared with traditional bolster dressings securing split-thickness skin grafts in a porcine model. We performed two split-thickness skin grafts on each of eight 30 kg Yorkshire pigs. We took graft biopsies on postoperative days 2, 4, 6, 8, and 10 and submitted the samples for immunohistochemical staining, as well as standard hematoxylin and eosin staining. We measured the degree of vascular ingrowth via immunohistochemical staining for von Willenbrand's factor to better identify blood vessel epithelium. We determined the mean cross-sectional area of blood vessels present for each representative specimen, and then compared the bolster and NPWT samples. We also assessed each graft for incorporation and survival at postoperative day 10. Our analysis of the data revealed that there was no statistically significant difference in the degree of vascular ingrowth as measured by mean cross-sectional capillary area (p = 0.23). We did not note any difference in graft survival or apparent incorporation on a macroscopic level, although standard hematoxylin and eosin staining indicated that microscopically, there seemed to be better subjective graft incorporation in the NPWT samples and a nonsignificant trend toward improved graft survival in the NPWT group. We were unable to demonstrate a significant difference in vessel ingrowth when comparing NPWT and traditional bolster methods for split-thickness skin graft fixation. More studies are needed to elucidate the manner by which NPWT exerts its effects and the true clinical magnitude of these

  12. Comparison of Negative Pressure Wound Therapy Using Vacuum-Assisted Closure with Advanced Moist Wound Therapy in the Treatment of Diabetic Foot Ulcers.

    Science.gov (United States)

    Sajid, Muhammad Tanveer; Mustafa, Qurat ul Ain; Shaheen, Neelofar; Hussain, Syed Mukarram; Shukr, Irfan; Ahmed, Muhammad

    2015-11-01

    To evaluate the clinical efficacy of Negative Pressure Wound Therapy (NPWT) using Vacuum Assisted Closure (VAC) compared with Advanced Moist Wound Therapy (AMWT) to treat Diabetic Foot Ulcer (DFU). Randomized control trial. Surgical Department, Combined Military Hospital (CMH) / Military Hospital (MH), Rawalpindi, from November 2010 to June 2012. The study consisted of 278 patients, with 139 patients each in Group 'A' and 'B', who were subjected to AMWT and NPWT, respectively. Wound was assessed digitally every week for 2 weeks. Wound dimension and surface area were determined using University of Texas Health Centre at San Antonio (UTHCSA) image tool version 3.0. Efficacies of AMWT and NPWT were compared in terms of reduction in wound area over 2 weeks. Mean age of presentation in group A was 55.88 ± 10.97 years while in group B, it was 56.83 ± 11.3 (p=0.48). Mean duration of diabetes at presentation was 15.65 ± 4.86 and 15.96 ± 5.79 years in group A and B, respectively (p=0.74). Majority of patients had Wagner's grade 2 ulcer (82% in group A and 87.8% in group B, p= 0.18). Initial wound size in group A was 15.07 ± 2.92 cm2 and in group B 15.09 ± 2.81 cm2 (p = 0.95). Wound size measured after 2 weeks, treatment was in group A13.70 ± 2.92 cm2 and in group B 11.53 ± 2.78 cm2 (p VAC was more efficacious than AMWT in the management of diabetic foot ulcers.

  13. Comparison of negative pressure wound therapy using vacuum-assisted closure with advanced moist wound therapy in the treatment of diabetic foot ulcers

    International Nuclear Information System (INIS)

    Sajid, M.T.; Mustafa, Q.U.A.

    2015-01-01

    Objective: To evaluate the clinical efficacy of Negative Pressure Wound Therapy (NPWT) using Vacuum Assisted Closure (VAC) compared with Advanced Moist Wound Therapy (AMWT) to treat Diabetic Foot Ulcer (DFU). Study Design: Randomized control trial. Place and Duration of Study: Surgical Department, Combined Military Hospital (CMH) / Military Hospital (MH), Rawalpindi, from November 2010 to June 2012. Methodology: The study consisted of 278 patients, with 139 patients each in Group A and B, who were subjected to AMWT and NPWT, respectively. Wound was assessed digitally every week for 2 weeks. Wound dimension and surface area were determined using University of Texas Health Centre at San Antonio (UTHCSA) image tool version 3.0. Efficacies of AMWT and NPWT were compared in terms of reduction in wound area over 2 weeks. Results: Mean age of presentation in group Awas 55.88 10.97 years while in group B, it was 56.83 ± 11.3 (p=0.48). Mean duration of diabetes at presentation was 15.65 ± 4.86 and 15.96 ± 5.79 years in group A and B, respectively (p=0.74). Majority of patients had Wagner's grade 2 ulcer (82% in group A and 87.8% in group B, p= 0.18). Initial wound size in group A was 15.07 ± 2.92 cm2and in group B 15.09 ± 2.81 cm2(p = 0.95). Wound size measured after 2 weeks, treatment was in group A13.70 ± 2.92 cm2 and in group B 11.53 ± 2.78 cm2 (p < 0.001). Wound area reduction in both groups revealed statistically significant faster healing in group B as compared to group A(p < 0.001). Conclusion: NPWT using VAC was more efficacious than AMWT in the management of diabetic foot ulcers. (author)

  14. Negative Pressure Wound Therapy versus modified Barker Vacuum Pack as temporary abdominal closure technique for Open Abdomen management: a four-year experience.

    Science.gov (United States)

    Montori, Giulia; Allievi, Niccolò; Coccolini, Federico; Solaini, Leonardo; Campanati, Luca; Ceresoli, Marco; Fugazzola, Paola; Manfredi, Roberto; Magnone, Stefano; Tomasoni, Matteo; Ansaloni, Luca

    2017-07-21

    We reviewed our experience with patients presenting with trauma and peritonitis who underwent an open abdomen (OA) procedure, and compared outcomes between Negative Pressure Wound Therapy (NPWT) and a modified Barker Vacuum Pack (mBVP) technique. In this descriptive study, we retrospectively analyzed data regarding all patients who underwent OA for intra-abdominal sepsis or abdominal trauma at our Centre from January 2012 to December 2015. Demographic data, co-morbidities, indications to surgery, intra-operative details and Björck classification grade were considered. Outcomes included were: time to closure in days, fascial closure rates, ICU and hospital stay, in-hospital and overall mortality, and entero-atmospheric fistula rate. A total of 83 cases were considered. Mean closure time was 6 days versus 6.5 days (p = 0.71) in NPWT and mBVP groups, respectively; the fascial closure rate was 75.4% versus 93.8% (p = 0.10). At multivariate analysis, in-hospital and overall mortality were significantly higher within the mBVP, as compared to NPWT (OR 3.8, 95% CI 1.1 to 13.1, p = 0.02 - OR 4.2, 95% CI 1.2 to 14.1, p = 0.01). Entero-atmospheric fistula rate was 2.6% in the two groups. NPWT as a temporary abdominal closure technique, as compared to mBVP, appears to be associated with better outcomes in terms of mortality.

  15. Application of a drainage film reduces fibroblast ingrowth into large-pored polyurethane foam during negative-pressure wound therapy in an in vitro model.

    Science.gov (United States)

    Wiegand, Cornelia; Springer, Steffen; Abel, Martin; Wesarg, Falko; Ruth, Peter; Hipler, Uta-Christina

    2013-01-01

    Negative-pressure wound therapy (NPWT) is an advantageous treatment option in wound management to promote healing and reduce the risk of complications. NPWT is mainly carried out using open-cell polyurethane (PU) foams that stimulate granulation tissue formation. However, growth of wound bed tissue into foam material, leading to disruption of newly formed tissue upon dressing removal, has been observed. Consequently, it would be of clinical interest to preserve the positive effects of open-cell PU foams while avoiding cellular ingrowth. The study presented analyzed effects of NPWT using large-pored PU foam, fine-pored PU foam, and the combination of large-pored foam with drainage film on human dermal fibroblasts grown in a collagen matrix. The results showed no difference between the dressings in stimulating cellular migration during NPWT. However, when NPWT was applied using a large-pored PU foam, the fibroblasts continued to migrate into the dressing. This led to significant breaches in the cell layers upon removal of the samples after vacuum treatment. In contrast, cell migration stopped at the collagen matrix edge when fine-pored PU foam was used, as well as with the combination of PU foam and drainage film. In conclusion, placing a drainage film between collagen matrix and the large-pored PU foam dressing reduced the ingrowth of cells into the foam significantly. Moreover, positive effects on cellular migration were not affected, and the effect of the foam on tissue surface roughness in vitro was also reduced. © 2013 by the Wound Healing Society.

  16. Use of collagenase ointment in conjunction with negative pressure wound therapy in the care of diabetic wounds: a case series of six patients

    Directory of Open Access Journals (Sweden)

    John D. Miller

    2015-01-01

    Full Text Available Background: Diabetic wounds with additional comorbidities are costly, time intensive, and difficult to heal. Often, multiple modalities may be necessary to achieve wound resolution, relying on the synergistic advantage of each therapy to affect wound healing. The selectivity of Clostridium collagenase is physiologically effective at degrading non-viable collagen fibers while preserving living collagen tissue. Additionally, negative pressure wound therapy (NPWT has long been used to aid wound healing while concurrently depreciating biological wound burden time. Methods: Six patients were selected from those appearing to our university based limb salvage service. Inclusion criteria included patients with a recurrent mixed fibrotic and granular wound base, in which NPWT was indicated, without exclusion criteria. Patients enrolled were administered clostridial collagenase ointment at each regularly scheduled NPWT dressing change. Patients were followed until healing, with visual representations of wound progression and time to full healing recorded. Results: Tandem application of these therapies appeared to expedite wound healing by clearing degenerative fibrous tissue and expediting wound granulation without additional complication. Unfortunately, not all patients were able to reach full healing; with two patients experiencing ulcer recurrence, likely a result of their significant comorbid nature. Conclusion: In our experience, we have noticed a specific subgroup of patients who benefit greatly when collagenase enzymatic debridement therapy is combined with NPWT. It is our belief that this combination therapy combines the molecular clearing of non-viable collagen with the wound granulation necessary to advance complex wounds to the next step in healing despite the current paucity in literature discussing this specific pairing.

  17. [Clinical efficacy of negative-pressure wound therapy combined with porcine acellular dermal matrix for repairing deep burn wounds in limbs].

    Science.gov (United States)

    Liu, Wei; Li, Feng; Chen, Xin; Pan, Qing

    2016-06-01

    To observe the clinical efficacy of negative pressure wound therapy (NPWT) in combination with porcine acellular dermal matrix (ADM) dressing for repairing deep burn wounds in limbs of patients with non-surgical treatment. Thirty-two patients with deep partial-thickness burn to full-thickness burn on the limbs admitted to our ward from June 2012 to December 2015, conforming to the inclusion criteria, were divided into group NPWT (n=10, treated with interval negative pressure drainage at -16.6 kPa), group ADM (n=7, treated with porcine ADM dressing), and group NPWT+ ADM (n=15, treated with interval negative pressure drainage and porcine ADM dressing as above) according to the random number table and patient's consent. After being treated for 21 d, residual wounds were cured by routine dressing change using sulfadiazine silver. On post treatment day (PTD) 7, 14, and 21, wound gross observation was conducted, wound drainage fluid volume was recorded, and wound healing rate was calculated. Wound secretion was collected for bacterial culture before treatment and on PTD 21, and bacterial clearance effect was recorded. The wound healing time was also recorded. Measurement data were processed with analysis of variance for repeated measurement, one-way analysis of variance, and LSD test. Eenumeration data were processed with chi-square test or Fisher's exact test. (1) On PTD 7, the wounds of patients in group NPWT and group NPWT+ ADM were significantly shrinked as compared with those before treatment. Skin paddle scattered on the wounds of patients in group NPWT+ ADM on PTD 7. The wounds of patients in group ADM were slightly shrinked on PTD 7 as compared with those before treatment. On PTD 14, the wounds of patients in group NPWT were slightly shrinked as compared with those on PTD 7, while those in group NPWT+ ADM were significantly shrinked as compared with those on PTD 7. Skin paddle on the wounds of patients in group NPWT+ ADM on PTD 14 were increased and fused. The

  18. Basal electric and magnetic fields of celestial bodies come from positive-negative charge separation caused by gravitation of quasi-Casimir pressure in weak interaction

    Science.gov (United States)

    Chen, Shao-Guang

    According to f =d(mv)/dt=m(dv/dt)+ v(dm/dt), a same gravitational formula had been de-duced from the variance in physical mass of QFT and from the variance in mass of inductive energy-transfer of GR respectively: f QF T = f GR = -G (mM/r2 )((r/r)+(v/c)) when their interaction-constants are all taken the experimental values (H05-0029-08, E15-0039-08). f QF T is the quasi-Casimir pressure. f GR is equivalent to Einstein's equation, then more easy to solve it. The hypothesis of the equivalent principle is not used in f QF T , but required by f GR . The predictions of f QF T and f GR are identical except that f QF T has quantum effects but f GR has not and f GR has Lense-Thirring effect but f QF T has not. The quantum effects of gravitation had been verified by Nesvizhevsky et al with the ultracold neutrons falling in the earth's gravitational field in 2002. Yet Lense-Thirring effect had not been measured by GP-B. It shows that f QF T is essential but f GR is phenomenological. The macro-f QF T is the statistic average pressure collided by net virtual neutrinos ν 0 flux (after self-offset in opposite directions) and in direct proportion to the mass. But micro-f QF T is in direct proportion to the scattering section. The electric mass (in inverse proportion to de Broglie wavelength λ) far less than nucleonic mass and the electric scattering section (in direct proportion to λ2 ) far large than that of nucleon, then the net ν 0 flux pressure exerted to electron far large than that to nucleon and the electric displacement far large than that of nucleon, it causes the gravitational polarization of positive-negative charge center separation. Because the gravity far less than the electromagnetic binding force, in atoms the gravitational polarization only produces a little separation. But the net ν 0 flux can press a part freedom electrons in plasma of ionosphere into the earth's surface, the static electric force of redundant positive ions prevents electrons from further

  19. Effect of expiratory muscle strength training on swallowing-related muscle strength in community-dwelling elderly individuals: a randomized controlled trial.

    Science.gov (United States)

    Park, Ji-Su; Oh, Dong-Hwan; Chang, Moon-Young

    2017-03-01

    This study aimed to investigate the effect of expiratory muscle strength training (EMST) on swallowing-related muscle strength in community-dwelling elderly individuals. Expiratory muscle strength training is an intervention for patients with oropharyngeal dysphagia. This training is associated with respiration, coughing, speech and swallowing, and its effectiveness has been proven in previous studies. However, the effects of EMST on elderly individuals and evidence are still lacking. This study included 24 community-dwelling senior citizens aged ≥65 years (12 men and 12 women). The experimental group trained at the 70% threshold value of the maximum expiratory pressure using an EMST device 5 days per week for 4 weeks and comprised five sets of five breaths through the device for 25 breaths per day. The placebo group trained with a resistance-free sham device. Post-intervention, muscle strength of the bilateral buccinator and the orbicularis oris muscles (OOM) was measured using the Iowa Oral Performance Instrument. Surface electromyography was used to measure activation of the suprahyoid muscles (SM). After intervention, the strength of the buccinator and the OOM in the experimental group showed statistically significant improvement. There was also statistically significant activation of the SM. In the placebo group, the strength of the orbicularis oris muscle alone improved. No statistically significant differences between groups were found for the strength of the buccinator and the OOM and the activation of the SM. EMST had a positive effect on swallowing-related muscle strength in elderly participants. © 2016 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

  20. Effects of manual rib cage compressions on expiratory flow and mucus clearance during mechanical ventilation.

    Science.gov (United States)

    Martí, Joan Daniel; Li Bassi, Gianluigi; Rigol, Montserrat; Saucedo, Lina; Ranzani, Otavio Tavares; Esperatti, Mariano; Luque, Nestor; Ferrer, Miquel; Vilaro, Jordi; Kolobow, Theodor; Torres, Antoni

    2013-03-01

    We investigated the effects of two different types of manual rib cage compression on expiratory flow and mucus clearance during prolonged mechanical ventilation in pigs. Prospective randomized animal study. Animal research facility, University of Barcelona, Spain. Nine healthy pigs. Pigs were tracheally intubated, sedated, paralyzed, and mechanically ventilated. The animals were prone on a surgical bed in the anti-Trendelenburg position. The experiments were carried out at approximately 60 and 80 hrs from the beginning of mechanical ventilation. Two types of manual rib cage compressions were tested: Hard and brief rib cage compressions synchronized with early expiratory phase (hard manual rib cage compression) and soft and gradual rib cage compressions applied during the late expiratory phase (soft manual rib cage compression). The intervent