WorldWideScience

Sample records for volume mechanical ventilation

  1. Pressure and volume controlled mechanical ventilation in anaesthetized pregnant sheep.

    Science.gov (United States)

    Davis, J; Musk, G C

    2014-10-01

    Optimal mechanical ventilation of the pregnant ewe during anaesthesia is of vital importance for maintaining fetal viability. This study aimed to compare peak inspiratory pressure (PIP), oxygenation and cardiovascular parameters with pressure-control (PCV) or volume-control (VCV) mechanical ventilation of anaesthetized pregnant sheep. Twenty ewes at 110 days gestation underwent general anaesthesia in dorsal recumbency for fetal surgery in a research setting. All the sheep were mechanically ventilated; one group with PCV (n = 10) and another with VCV (n = 10) to maintain normocapnia. PIP, direct arterial blood pressure, heart rate, arterial pH and arterial oxygen tension were recorded. PIP was lower in the PCV group (P sheep anaesthetized in dorsal recumbency, though PCV may provide superior oxygenation at a lower PIP.

  2. Increasing inspiratory time exacerbates ventilator-induced lung injury during high-pressure/high-volume mechanical ventilation.

    Science.gov (United States)

    Casetti, Alfredo V; Bartlett, Robert H; Hirschl, Ronald B

    2002-10-01

    Ventilator-induced lung injury may be caused by overdistension of alveoli during high-pressure ventilation. In this study, we examined the effects of increasing inspiratory time on ventilator-induced lung injury. Sprague-Dawley rats were divided into four different groups with ten animals per group. Each group was then ventilated for 30 mins with one of four ventilator strategies. All groups were ventilated with an Fio2 of 1.0 and a positive end-expiratory pressure of 0 cm H2O. Group LoP was the negative control group and was ventilated with low pressures (peak inspiratory pressure = 12 cm H2O, rate = 30, and inspiratory time = 0.5 secs). Groups iT = 0.5, iT = 1.0, and iT = 1.5 were the experimental groups and were ventilated with high pressures (peak inspiratory pressure = 45 cm H2O, rate = 10, and inspiratory times = 0.5 secs, iT = 1.0 sec, and iT = 1.5 secs, respectively). Outcome measures included lung compliance, Pao /Fio ratio, wet/dry lung weight, and dry lung/body weight. Final static lung compliance (p =.0002) and Pao2/Fio2 (p =.001) decreased as inspiratory time increased. Wet/dry lung weights (p <.0001) and dry lung/body weights (p <.0001) increased as inspiratory time increased. Light microscopy revealed evidence of intra-alveolar edema and hemorrhage in the iT = 1.0 and iT = 1.5 animals but not the LoP and iT = 0.5 animals. Increasing inspiratory time during high-pressure/high-volume mechanical ventilation is associated with an increase in variables of lung injury.

  3. The Effect of Pressure-Controlled Ventilation and Volume-Controlled Ventilation in Prone Position on Pulmonary Mechanics and Inflammatory Markers.

    Science.gov (United States)

    Şenay, Hasan; Sıvacı, Remziye; Kokulu, Serdar; Koca, Buğra; Bakı, Elif Doğan; Ela, Yüksel

    2016-08-01

    The aim of this present study is to compare the effect of pressure-controlled ventilation and volume-controlled ventilation on pulmonary mechanics and inflammatory markers in prone position. The study included 41 patients undergoing to vertebrae surgery. The patients were randomized into two groups: Group 1 received volume-controlled ventilation, while group 2 received pressure-controlled ventilation. The demographic data, pulmonary mechanics, the inflammatory marker levels just after the induction of anesthetics, at the 6th and 12th hours, and gas analysis from arterial blood samples taken at the beginning and the 30th minute were recorded. The inflammatory marker levels increased in both groups, without any significant difference among groups. Peak inspiratory pressure level was higher in the volume-controlled ventilation group. This study revealed that there is no difference regarding inflammatory marker levels between volume- and pressure-controlled ventilation.

  4. Mechanical ventilation with lower tidal volumes does not influence the prescription of opioids or sedatives

    NARCIS (Netherlands)

    Wolthuis, Esther K; Veelo, Denise P; Choi, Goda; Determann, Rogier M; Korevaar, Johanna C; Spronk, Peter E; Kuiper, Michael A; Schultz, Marcus J

    2007-01-01

    INTRODUCTION: We compared the effects of mechanical ventilation with a lower tidal volume (V(T)) strategy versus those of greater V(T) in patients with or without acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) on the use of opioids and sedatives. METHODS: This is a secondary anal

  5. Influence of fluid and volume state on PaO2 oscillations in mechanically ventilated pigs.

    Science.gov (United States)

    Bodenstein, Marc; Bierschock, Stephan; Boehme, Stefan; Wang, Hemei; Vogt, Andreas; Kwiecien, Robert; David, Matthias; Markstaller, Klaus

    2013-03-01

    Varying pulmonary shunt fractions during the respiratory cycle cause oxygen oscillations during mechanical ventilation. In artificially damaged lungs, cyclical recruitment of atelectasis is responsible for varying shunt according to published evidence. We introduce a complimentary hypothesis that cyclically varying shunt in healthy lungs is caused by cyclical redistribution of pulmonary perfusion. Administration of crystalloid or colloid infusions would decrease oxygen oscillations if our hypothesis was right. Therefore, n=14 mechanically ventilated healthy pigs were investigated in 2 groups: crystalloid (fluid) versus no-fluid administration. Additional volume interventions (colloid infusion, blood withdrawal) were carried out in each pig. Intra-aortal PaO2 oscillations were recorded using fluorescence quenching technique. Phase shift of oxygen oscillations during altered inspiratory to expiratory (I:E) ventilation ratio and electrical impedance tomography (EIT) served as control methods to exclude that recruitment of atelectasis is responsible for oxygen oscillations. In hypovolemia relevant oxygen oscillations could be recorded. Fluid and volume state changed PaO2 oscillations according to our hypothesis. Fluid administration led to a mean decline of 105.3 mmHg of the PaO2 oscillations amplitude (PPaO2 oscillations.

  6. Enteral nutrition volume is not correlated with lower respiratory tract infection in patients on mechanical ventilation.

    Science.gov (United States)

    Colomar, A; Guardiola, B; Llompart-Pou, J A; Ayestarán, I; Rodríguez-Pilar, J; Ferreruela, M; Raurich, J M

    To evaluate the effect of enteral nutrition volume, gastrointestinal function and the type of acid suppressive drug upon the incidence of lower respiratory tract infections in critically ill patients on mechanical ventilation (MV). A retrospective secondary analysis was carried out. The Intensive Care Unit of a University Hospital. Patients≥18-years-old expected to need MV for more than four days, and receiving enteral nutrition by nasogastric tube within 24h of starting MV. We correlated enteral nutrition volume administered during the first 10 days, gastrointestinal function and the type of acid suppressive therapy with the episodes of lower respiratory tract infection up until day 28. Cox proportional hazards ratios in univariate and adjusted multivariate models were used. Statistical significance was considered for p<0.05. Lower respiratory tract infection episodes. Sixty-six out of 185 patients (35.7%) had infection; 27 patients had ventilator-associated pneumonia; and 39 presented ventilator-associated tracheobronchitis. Uninfected and infected groups were similar in terms of enteral nutrition volume (54±12 and 54±9mL/h; p=0.94) and caloric intake (19.4±4.9 and 19.6±5.2kcal/kg/d; p=0.81). The Cox proportional hazards model showed neurological indication of MV to be the only independent variable related to infection (p=0.001). Enteral nutrition volume, the type of acid suppressive therapy, and the use of prokinetic agents were not significantly correlated to infection. Enteral nutrition volume and caloric intake, gastrointestinal dysfunction and the type of acid suppressive therapy used were not associated to lower respiratory tract infection in patients on MV. Copyright © 2016 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  7. Complications of mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Drašković Biljana

    2011-01-01

    Full Text Available Mechanical ventilation of the lungs, as an important therapeutic measure, cannot be avoided in critically ill patients. However, when machines take over some of vital functions there is always a risk of complications and accidents. Complications associated with mechanical ventilation can be divided into: 1 airway-associated complications; 2 complications in the response of patients to mechanical ventilation; and 3 complications related to the patient’s response to the device for mechanical ventilation. Complications of artificial airway may be related to intubation and extubation or the endotracheal tube. Complications of mechanical ventilation, which arise because of the patient’s response to mechanical ventilation, may primarily cause significant side effects to the lungs. During the last two decades it was concluded that mechanical ventilation can worsen or cause acute lung injury. Mechanical ventilation may increase the alveolar/capillary permeability by overdistension of the lungs (volutrauma, it can exacerbate lung damage due to the recruitment/derecruitment of collapsed alveoli (atelectrauma and may cause subtle damages due to the activation of inflammatory processes (biotrauma. Complications caused by mechanical ventilation, beside those involving the lungs, can also have significant effects on other organs and organic systems, and can be a significant factor contributing to the increase of morbidity and mortality in critically ill of mechanically ventilated patients. Complications are fortunately rare and do not occur in every patient, but due to their seriousness and severity they require extensive knowledge, experience and responsibility by health-care workers.

  8. A sigmoidal fit for pressure-volume curves of idiopathic pulmonary fibrosis patients on mechanical ventilation: clinical implications

    Directory of Open Access Journals (Sweden)

    Juliana C. Ferreira

    2011-01-01

    Full Text Available OBJECTIVE: Respiratory pressure-volume curves fitted to exponential equations have been used to assess disease severity and prognosis in spontaneously breathing patients with idiopathic pulmonary fibrosis. Sigmoidal equations have been used to fit pressure-volume curves for mechanically ventilated patients but not for idiopathic pulmonary fibrosis patients. We compared a sigmoidal model and an exponential model to fit pressure-volume curves from mechanically ventilated patients with idiopathic pulmonary fibrosis. METHODS: Six idiopathic pulmonary fibrosis patients and five controls underwent inflation pressure-volume curves using the constant-flow technique during general anesthesia prior to open lung biopsy or thymectomy. We identified the lower and upper inflection points and fit the curves with an exponential equation, V = A-B.e-k.P, and a sigmoid equation, V = a+b/(1+e-(P-c/d. RESULTS: The mean lower inflection point for idiopathic pulmonary fibrosis patients was significantly higher (10.5 ± 5.7 cm H2O than that of controls (3.6 ± 2.4 cm H2O. The sigmoidal equation fit the pressure-volume curves of the fibrotic and control patients well, but the exponential equation fit the data well only when points below 50% of the inspiratory capacity were excluded. CONCLUSION: The elevated lower inflection point and the sigmoidal shape of the pressure-volume curves suggest that respiratory system compliance is decreased close to end-expiratory lung volume in idiopathic pulmonary fibrosis patients under general anesthesia and mechanical ventilation. The sigmoidal fit was superior to the exponential fit for inflation pressure-volume curves of anesthetized patients with idiopathic pulmonary fibrosis and could be useful for guiding mechanical ventilation during general anesthesia in this condition.

  9. Mechanical ventilation of the premature neonate.

    Science.gov (United States)

    Brown, Melissa K; DiBlasi, Robert M

    2011-09-01

    Although the trend in the neonatal intensive care unit is to use noninvasive ventilation whenever possible, invasive ventilation is still often necessary for supporting pre-term neonates with lung disease. Many different ventilation modes and ventilation strategies are available to assist with the optimization of mechanical ventilation and prevention of ventilator-induced lung injury. Patient-triggered ventilation is favored over machine-triggered forms of invasive ventilation for improving gas exchange and patient-ventilator interaction. However, no studies have shown that patient-triggered ventilation improves mortality or morbidity in premature neonates. A promising new form of patient-triggered ventilation, neurally adjusted ventilatory assist (NAVA), was recently FDA approved for invasive and noninvasive ventilation. Clinical trials are underway to evaluate outcomes in neonates who receive NAVA. New evidence suggests that volume-targeted ventilation modes (ie, volume control or pressure control with adaptive targeting) may provide better lung protection than traditional pressure control modes. Several volume-targeted modes that provide accurate tidal volume delivery in the face of a large endotracheal tube leak were recently introduced to the clinical setting. There is ongoing debate about whether neonates should be managed invasively with high-frequency ventilation or conventional ventilation at birth. The majority of clinical trials performed to date have compared high-frequency ventilation to pressure control modes. Future trials with premature neonates should compare high-frequency ventilation to conventional ventilation with volume-targeted modes. Over the last decade many new promising approaches to lung-protective ventilation have evolved. The key to protecting the neonatal lung during mechanical ventilation is optimizing lung volume and limiting excessive lung expansion, by applying appropriate PEEP and using shorter inspiratory time, smaller tidal

  10. Despite variation in volume, Veterans Affairs hospitals show consistent outcomes among patients with non-postoperative mechanical ventilation.

    Science.gov (United States)

    Cooke, Colin R; Kennedy, Edward H; Wiitala, Wyndy L; Almenoff, Peter L; Sales, Anne E; Iwashyna, Theodore J

    2012-09-01

    To assess the relationship between volume of nonoperative mechanically ventilated patients receiving care in a specific Veterans Health Administration hospital and their mortality. Retrospective cohort study. One-hundred nineteen Veterans Health Administration medical centers. We identified 5,131 hospitalizations involving mechanically ventilated patients in an intensive care unit during 2009, who did not receive surgery. None. We extracted demographic and clinical data from the VA Inpatient Evaluation Center. For each hospital, we defined volume as the total number of nonsurgical admissions receiving mechanical ventilation in an intensive care unit during 2009. We examined the hospital contribution to 30-day mortality using multilevel logistic regression models with a random intercept for each hospital. We quantified the extent of interhospital variation in 30-day mortality using the intraclass correlation coefficient and median odds ratio. We used generalized estimating equations to examine the relationship between volume and 30-day mortality and risk-adjusted all models using a patient-level prognostic score derived from clinical data representing the risk of death conditional on treatment at a high-volume hospital. Mean age for the sample was 65 (SD 11) yrs, 97% were men, and 60% were white. The median VA hospital cared for 40 (interquartile range 19-62) mechanically ventilated patients in 2009. Crude 30-day mortality for these patients was 36.9%. After reliability and risk adjustment to the median patient, adjusted hospital-level mortality varied from 33.5% to 40.6%. The intraclass correlation coefficient for the hospital-level variation was 0.6% (95% confidence interval 0.1, 3.4%), with a median odds ratio of 1.15 (95% confidence interval 1.06, 1.38). The relationship between hospital volume of mechanically ventilated and 30-day mortality was not statistically significant: each 50-patient increase in volume was associated with a nonsignificant 2% decrease in

  11. Pulmonary mechanics during mechanical ventilation.

    Science.gov (United States)

    Henderson, William R; Sheel, A William

    2012-03-15

    The use of mechanical ventilation has become widespread in the management of hypoxic respiratory failure. Investigations of pulmonary mechanics in this clinical scenario have demonstrated that there are significant differences in compliance, resistance and gas flow when compared with normal subjects. This paper will review the mechanisms by which pulmonary mechanics are assessed in mechanically ventilated patients and will review how the data can be used for investigative research purposes as well as to inform rational ventilator management.

  12. Mechanical ventilation in children.

    Science.gov (United States)

    Kendirli, Tanil; Kavaz, Asli; Yalaki, Zahide; Oztürk Hişmi, Burcu; Derelli, Emel; Ince, Erdal

    2006-01-01

    Mechanical ventilation can be lifesaving, but > 50% of complications in conditions that require intensive care are related to ventilatory support, particularly if it is prolonged. We retrospectively evaluated the medical records of patients who had mechanical ventilation in the Pediatric Intensive Care Unit (PICU) during a follow-up period between January 2002-May 2005. Medical records of 407 patients were reviewed. Ninety-one patients (22.3%) were treated with mechanical ventilation. Ages of all patients were between 1-180 (median: 8) months. The mechanical ventilation time was 18.8 +/- 14.1 days. Indication of mechanical ventilation could be divided into four groups as respiratory failure (64.8%), cardiovascular failure (19.7%), central nervous system disease (9.8%) and safety airway (5.4%). Tracheostomy was performed in four patients. The complication ratio of mechanically ventilated children was 42.8%, and diversity of complications was as follows: 26.3% atelectasia, 17.5% ventilator-associated pneumonia, 13.1% pneumothorax, 5.4% bleeding, 4.3% tracheal edema, and 2.1% chronic lung disease. The mortality rate of mechanically ventilated patients was 58.3%, but the overall mortality rate in the PICU was 12.2%. In conclusion, there are few published epidemiological data on the follow-up results and mortality in infants and children who are mechanically ventilated.

  13. FCT (functional computed tomography) evaluation of the lung volumes at different PEEP (positive-end expiratory pressure) ventilation pattern, in mechanical ventilated patients

    Energy Technology Data Exchange (ETDEWEB)

    Papi, M.G.; Di Segni, R.; Mazzetti, G.; Staffa, F. [Dept. of Radiology, S. Giovanni HS, Rome (Italy); Conforto, F.; Calimici, R.; Salvi, A. [Dept. of Anesthesiology, S. Giovanni HS, Rome (Italy); Matteucci, G. [Dept. of Pneumology, S. Giovanni HS, Rome (Italy)

    2007-06-15

    Purpose To evaluate with FCT (functional computed tomography) total lung volume and fractional lung volumes at different PEEP (positive end expiratory pressure) values in acute mechanically ventilated patients. Methods Nine ICU (intensive care unity) patients (1 lung pneumonia, 2 polytrauma, 2 sepsis, 3 brain surgery, 1 pulmonary embolism); mean age 48 {+-} 15 years, 6 male, 3 female; GE 16 MDCT scan was performed with acquisition from apex to diaphragma in seven seca at different PEEP values. Raw CT data were analysed by an advantage workstation to obtain volume density masks and histograms of both lungs and each lung and these density ranges were applied: - 1000 - 950 = hyper-ventilated lung, -900 - 650 well aerated lung, -950 - 500 all aerated lung, -500 + 200 lung tissue. Total and fractional lung volumes, Hounsfield unit (HU) were calculated and compared at different PEEP values (0, 5, 10, 15 cm H{sub 2}O). In four patients lung volumes were compared between the more and the less involved lung at increased PEEP. Statistic analysis: comparison means-medians tests. Results Data calculated at five PEEP showed unexpected decrease of total lung volume and increase of lung density (HU); proportionally no significant improvement of oxigenation. (orig.)

  14. Changes in Stroke Volume Induced by Lung Recruitment Maneuver Predict Fluid Responsiveness in Mechanically Ventilated Patients in the Operating Room.

    Science.gov (United States)

    Biais, Matthieu; Lanchon, Romain; Sesay, Musa; Le Gall, Lisa; Pereira, Bruno; Futier, Emmanuel; Nouette-Gaulain, Karine

    2017-02-01

    Lung recruitment maneuver induces a decrease in stroke volume, which is more pronounced in hypovolemic patients. The authors hypothesized that the magnitude of stroke volume reduction through lung recruitment maneuver could predict preload responsiveness. Twenty-eight mechanically ventilated patients with low tidal volume during general anesthesia were included. Heart rate, mean arterial pressure, stroke volume, and pulse pressure variations were recorded before lung recruitment maneuver (application of continuous positive airway pressure of 30 cm H2O for 30 s), during lung recruitment maneuver when stroke volume reached its minimal value, and before and after volume expansion (250 ml saline, 0.9%, infused during 10 min). Patients were considered as responders to fluid administration if stroke volume increased greater than or equal to 10%. Sixteen patients were responders. Lung recruitment maneuver induced a significant decrease in mean arterial pressure and stroke volume in both responders and nonresponders. Changes in stroke volume induced by lung recruitment maneuver were correlated with those induced by volume expansion (r = 0.56; P recruitment maneuver predicted fluid responsiveness with a sensitivity of 88% (95% CI, 62 to 98) and a specificity of 92% (95% CI, 62 to 99). Pulse pressure variations more than 6% before lung recruitment maneuver discriminated responders with a sensitivity of 69% (95% CI, 41 to 89) and a specificity of 75% (95% CI, 42 to 95). The area under receiver operating curves generated for changes in stroke volume induced by lung recruitment maneuver (0.96; 95% CI, 0.81 to 0.99) was significantly higher than that for pulse pressure variations (0.72; 95% CI, 0.52 to 0.88; P recruitment maneuver could predict preload responsiveness in mechanically ventilated patients in the operating room.

  15. Mild hypothermia attenuates changes in respiratory system mechanics and modifies cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation.

    Science.gov (United States)

    Dostál, P; Senkeřík, M; Pařízková, R; Bareš, D; Zivný, P; Zivná, H; Cerný, V

    2010-01-01

    Hypothermia was shown to attenuate ventilator-induced lung injury due to large tidal volumes. It is unclear if the protective effect of hypothermia is maintained under less injurious mechanical ventilation in animals without previous lung injury. Tracheostomized rats were randomly allocated to non-ventilated group (group C) or ventilated groups of normothermia (group N) and mild hypothermia (group H). After two hours of mechanical ventilation with inspiratory fraction of oxygen 1.0, respiratory rate 60 min(-1), tidal volume 10 ml x kg(-1), positive end-expiratory pressure (PEEP) 2 cm H2O or immediately after tracheostomy in non-ventilated animals inspiratory pressures were recorded, rats were sacrificed, pressure-volume (PV) curve of respiratory system constructed, bronchoalveolar lavage (BAL) fluid and aortic blood samples obtained. Group N animals exhibited a higher rise in peak inspiratory pressures in comparison to group H animals. Shift of the PV curve to right, higher total protein and interleukin-6 levels in BAL fluid were observed in normothermia animals in comparison with hypothermia animals and non-ventilated controls. Tumor necrosis factor-alpha was lower in the hypothermia group in comparison with normothermia and non-ventilated groups. Mild hypothermia attenuated changes in respiratory system mechanics and modified cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation in animals without previous lung injury.

  16. Stroke volume variation compared with pulse pressure variation and cardiac index changes for prediction of fluid responsiveness in mechanically ventilated patients

    Directory of Open Access Journals (Sweden)

    Randa Aly Soliman

    2015-04-01

    Conclusions: Baseline stroke volume variation ⩾8.15% predicted fluid responsiveness in mechanically ventilated patients with acute circulatory failure. The study also confirmed the ability of pulse pressure variation to predict fluid responsiveness.

  17. Intraoperative mechanical ventilation for the pediatric patient.

    Science.gov (United States)

    Kneyber, Martin C J

    2015-09-01

    Invasive mechanical ventilation is required when children undergo general anesthesia for any procedure. It is remarkable that one of the most practiced interventions such as pediatric mechanical ventilation is hardly supported by any scientific evidence but rather based on personal experience and data from adults, especially as ventilation itself is increasingly recognized as a harmful intervention that causes ventilator-induced lung injury. The use of low tidal volume and higher levels of positive end-expiratory pressure became an integral part of lung-protective ventilation following the outcomes of clinical trials in critically ill adults. This approach has been readily adopted in pediatric ventilation. However, a clear association between tidal volume and mortality has not been ascertained in pediatrics. In fact, experimental studies have suggested that young children might be less susceptible to ventilator-induced lung injury. As such, no recommendations on optimal lung-protective ventilation strategy in children with or without lung injury can be made.

  18. Conventional mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Tobias Joseph

    2010-01-01

    Full Text Available The provision of mechanical ventilation for the support of infants and children with respiratory failure or insufficiency is one of the most common techniques that are performed in the Pediatric Intensive Care Unit (PICU. Despite its widespread application in the PICUs of the 21st century, before the 1930s, respiratory failure was uniformly fatal due to the lack of equipment and techniques for airway management and ventilatory support. The operating rooms of the 1950s and 1960s provided the arena for the development of the manual skills and the refinement of the equipment needed for airway management, which subsequently led to the more widespread use of endotracheal intubation thereby ushering in the era of positive pressure ventilation. Although there seems to be an ever increasing complexity in the techniques of mechanical ventilation, its successful use in the PICU should be guided by the basic principles of gas exchange and the physiology of respiratory function. With an understanding of these key concepts and the use of basic concepts of mechanical ventilation, this technique can be successfully applied in both the PICU and the operating room. This article reviews the basic physiology of gas exchange, principles of pulmonary physiology, and the concepts of mechanical ventilation to provide an overview of the knowledge required for the provision of conventional mechanical ventilation in various clinical arenas.

  19. Effects of pressure-controlled and volume-controlled ventilation on respiratory mechanics and systemic stress response during prone position.

    Science.gov (United States)

    Sen, Oznur; Bakan, Mefkur; Umutoglu, Tarik; Aydın, Nurdan; Toptas, Mehmet; Akkoc, Ibrahim

    2016-01-01

    Prone position during general anesthesia for special surgical operations may be related with increased airway pressure, decreased pulmonary and thoracic compliance that may be explained by restriction of chest expansion and compression of abdomen. The optimum ventilation mode for anesthetized patients on prone position was not described and studies comparing volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) during prone position are limited. We hypothesized that PCV instead of VCV during prone position could achieve lower airway pressures and reduce the systemic stress response. In this study, we aimed to compare the effects of PCV and VCV modes during prone position on respiratory mechanics, oxygenation, and hemodynamics, as well as blood cortisol and insulin levels, which has not been investigated before. Fifty-four ASA I-II patients, 18-70 years of age, who underwent percutaneous nephrolithotomy on prone position, were randomly selected to receive either the PCV (Group PC, n = 27) or VCV (Group VC, n = 27) under general anesthesia with sevoflurane and fentanyl. Blood sampling was made for baseline arterial blood gases (ABG), cortisol, insulin, and glucose levels. After anesthesia induction and endotracheal intubation, patients in Group PC were given pressure support to form 8 mL/kg tidal volume and patients in Group VC was maintained at 8 mL/kg tidal volume calculated using predicted body weight. All patients were maintained with 5 cmH2O PEEP. Respiratory parameters were recorded during supine and prone position. Assessment of ABG and sampling for cortisol, insulin and glucose levels were repeated during surgery and 60 min after extubation. P-peak and P-plateau levels during supine and prone positions were significantly higher and P-mean and compliance levels during prone position were significantly lower in Group VC when compared with Group PC. Postoperative PaO2 level was significantly higher in Group PC compared with Group

  20. Mechanical ventilation in neurosurgical patients

    Directory of Open Access Journals (Sweden)

    Keshav Goyal

    2013-01-01

    Full Text Available Mechanical ventilation significantly affects cerebral oxygenation and cerebral blood flow through changes in arterial carbon dioxide levels. Neurosurgical patients might require mechanical ventilation for correction and maintenance of changes in the pulmonary system that occur either due to neurosurgical pathology or following surgery during the acute phase. This review discusses the basics of mechanical ventilation relevant to the neurosurgeon in the day-to-day management of neurosurgical patient requiring artificial support of the respiration.

  1. Ventilation and respiratory mechanics.

    Science.gov (United States)

    Sheel, Andrew William; Romer, Lee M

    2012-04-01

    During dynamic exercise, the healthy pulmonary system faces several major challenges, including decreases in mixed venous oxygen content and increases in mixed venous carbon dioxide. As such, the ventilatory demand is increased, while the rising cardiac output means that blood will have considerably less time in the pulmonary capillaries to accomplish gas exchange. Blood gas homeostasis must be accomplished by precise regulation of alveolar ventilation via medullary neural networks and sensory reflex mechanisms. It is equally important that cardiovascular and pulmonary system responses to exercise be precisely matched to the increase in metabolic requirements, and that the substantial gas transport needs of both respiratory and locomotor muscles be considered. Our article addresses each of these topics with emphasis on the healthy, young adult exercising in normoxia. We review recent evidence concerning how exercise hyperpnea influences sympathetic vasoconstrictor outflow and the effect this might have on the ability to perform muscular work. We also review sex-based differences in lung mechanics.

  2. Respiratory mechanics in mechanically ventilated patients.

    Science.gov (United States)

    Hess, Dean R

    2014-11-01

    Respiratory mechanics refers to the expression of lung function through measures of pressure and flow. From these measurements, a variety of derived indices can be determined, such as volume, compliance, resistance, and work of breathing. Plateau pressure is a measure of end-inspiratory distending pressure. It has become increasingly appreciated that end-inspiratory transpulmonary pressure (stress) might be a better indicator of the potential for lung injury than plateau pressure alone. This has resulted in a resurgence of interest in the use of esophageal manometry in mechanically ventilated patients. End-expiratory transpulmonary pressure might also be useful to guide the setting of PEEP to counterbalance the collapsing effects of the chest wall. The shape of the pressure-time curve might also be useful to guide the setting of PEEP (stress index). This has focused interest in the roles of stress and strain to assess the potential for lung injury during mechanical ventilation. This paper covers both basic and advanced respiratory mechanics during mechanical ventilation.

  3. Inhalation therapy in mechanical ventilation

    Science.gov (United States)

    Maccari, Juçara Gasparetto; Teixeira, Cassiano; Gazzana, Marcelo Basso; Savi, Augusto; Dexheimer-Neto, Felippe Leopoldo; Knorst, Marli Maria

    2015-01-01

    Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients. PMID:26578139

  4. Low-energy mechanical ventilation

    DEFF Research Database (Denmark)

    Andersen, Claus Wessel; Hviid, Christian Anker

    2014-01-01

    and with as little energy consumption as 41.1 kWh/m2/year including heating and all building services with no use of renewable energy such as PVcells or solar heating. One of the key means of reaching the objectives was to implement mechanical ventilation with low pressure loss and therefore low energy consumption....... The project consists of two buildings, building one is 6 stories high, and building two is 4 stories high. The buildings have a gross area of 50,500 m2 including underground parking. The ventilation and indoor climate concept was to use mechanical ventilation together with mechanical cooling and fanassisted...

  5. Electrical Impedance Tomography During Mechanical Ventilation.

    Science.gov (United States)

    Walsh, Brian K; Smallwood, Craig D

    2016-10-01

    Electrical impedance tomography (EIT) is a noninvasive, non-radiologic imaging modality that may be useful for the quantification of lung disorders and titration of mechanical ventilation. The principle of operation is based on changes in electrical conductivity that occur as a function of changes in lung volume during ventilation. EIT offers potentially important benefits over standard imaging modalities because the system is portable and non-radiologic and can be applied to patients for long periods of time. Rather than providing a technical dissection of the methods utilized to gather, compile, reconstruct, and display EIT images, the present article seeks to provide an overview of the clinical application of this technology as it relates to monitoring mechanical ventilation and providing decision support at the bedside. EIT has been shown to be useful in the detection of pneumothoraces, quantification of pulmonary edema and comparison of distribution of ventilation between different modes of ventilation and may offer superior individual titration of PEEP and other ventilator parameters compared with existing approaches. Although application of EIT is still primarily done within a research context, it may prove to be a useful bedside tool in the future. However, head-to-head comparisons with existing methods of mechanical ventilation titration in humans need to be conducted before its application in general ICUs can be recommended. Copyright © 2016 by Daedalus Enterprises.

  6. Assessment of mechanical ventilation parameters on respiratory mechanics.

    Science.gov (United States)

    Pidaparti, Ramana M; Koombua, Kittisak; Ward, Kevin R

    2012-01-01

    Better understanding of airway mechanics is very important in order to avoid lung injuries for patients undergoing mechanical ventilation for treatment of respiratory problems in intensive-care medicine, as well as pulmonary medicine. Mechanical ventilation depends on several parameters, all of which affect the patient outcome. As there are no systematic numerical investigations of the role of mechanical ventilation parameters on airway mechanics, the objective of this study was to investigate the role of mechanical ventilation parameters on airway mechanics using coupled fluid-solid computational analysis. For the airway geometry of 3 to 5 generations considered, the simulation results showed that airflow velocity increased with increasing airflow rate. Airway pressure increased with increasing airflow rate, tidal volume and positive end-expiratory pressure (PEEP). Airway displacement and airway strains increased with increasing airflow rate, tidal volume and PEEP form mechanical ventilation. Among various waveforms considered, sine waveform provided the highest airflow velocity and airway pressure while descending waveform provided the lowest airway pressure, airway displacement and airway strains. These results combined with optimization suggest that it is possible to obtain a set of mechanical ventilation strategies to avoid lung injuries in patients.

  7. Mechanical ventilation in rural ICUs.

    Science.gov (United States)

    Fieselmann; Bock; Hendryx; Wakefield; Helms; Bentler

    1999-01-01

    BACKGROUND: In recent years, rural hospitals have expanded their scope of specialized services, which has led to the development and staffing of rural intensive care units (ICUs). There is little information about the breadth, quality or outcomes of these services. This is particularly true for specialized ICU services such as mechanical ventilation, where little, if any, information exists specifically for rural hospitals. The long-term objectives of this project were to evaluate the quality of medical care provided to mechanically ventilated patients in rural ICUs and to improve patient care through an educational intervention. This paper reports baseline data on patient and hospital characteristics for both rural and rural referral hospitals. RESULTS: Twenty Iowa hospitals were evaluated. Data collected on 224 patients demonstrated a mean age of 70 years and a mean ICU admission Acute Physiology and Chronic Health Evaluation (APACHE) II score of 22, with an associated 36% mortality. Mean length of ICU stay was 10 days, with 7.7 ventilated days. Significant differences were found in both institutional and patient variables between rural referral hospitals and rural hospitals with more limited resources. A subgroup of patients with diagnoses associated with complex ventilation had higher mortality rates than patients without these conditions. Patients who developed nosocomial events had longer mean ventilator and ICU days than patients without nosocomial events. This study also found ICU practices that frequently fell outside the guidelines recommended by a task force describing minimum standards of care for critically ill patients with acute respiratory failure on mechanical ventilation. CONCLUSIONS: Despite distinct differences in the available resources between rural referral and rural hospitals, overall mortality rates of ventilated patients are similar. Considering the higher mortality rates observed in patients with complicated medical conditions requiring

  8. Effects of pressure-controlled and volume-controlled ventilation on respiratory mechanics and systemic stress response during laparoscopic cholecystectomy.

    Science.gov (United States)

    Sen, Oznur; Umutoglu, Tarik; Aydın, Nurdan; Toptas, Mehmet; Tutuncu, Ayse Cigdem; Bakan, Mefkur

    2016-01-01

    Pressure-controlled ventilation (PCV) is less frequently employed in general anesthesia. With its high and decelerating inspiratory flow, PCV has faster tidal volume delivery and different gas distribution. The same tidal volume setting, delivered by PCV versus volume-controlled ventilation (VCV), will result in a lower peak airway pressure and reduced risk of barotrauma. We hypothesized that PCV instead of VCV during laparoscopic surgery could achieve lower airway pressures and reduce the systemic stress response. Forty ASA I-II patients were randomly selected to receive either the PCV (Group PC, n = 20) or VCV (Group VC, n = 20) during laparoscopic cholecystectomy. Blood sampling was made for baseline arterial blood gases (ABG), cortisol, insulin, and glucose levels. General anesthesia with sevoflurane and fentanyl was employed to all patients. After anesthesia induction and endotracheal intubation, patients in Group PC were given pressure support to form 8 mL/kg tidal volume and patients in Group VC was maintained at 8 mL/kg tidal volume calculated using predicted body weight. All patients were maintained with 5 cmH2O positive-end expiratory pressure (PEEP). Respiratory parameters were recorded before and 30 min after pneumoperitonium. Assessment of ABG and sampling for cortisol, insulin and glucose levels were repeated 30 min after pneumoperitonium and 60 min after extubation. The P-peak levels observed before (18.9 ± 3.8 versus 15 ± 2.2 cmH2O) and during (23.3 ± 3.8 versus 20.1 ± 2.9 cmH2O) pneumoperitoneum in Group VC were significantly higher. Postoperative partial arterial oxygen pressure (PaO2) values are higher (98 ± 12 versus 86 ± 11 mmHg) in Group PC. Arterial carbon dioxide pressure (PaCO2) values (41.8 ± 5.4 versus 36.7 ± 3.5 mmHg) during pneumoperitonium and post-operative mean cortisol and insulin levels were higher in Group VC. When compared to VCV mode, PCV mode may improve compliance during pneumoperitoneum

  9. Effect of Switching between Pressure-controlled and Volume-controlled Ventilation on Respiratory Mechanics and Hemodynamics in Obese Patients during Abdominoplasty

    Science.gov (United States)

    Messeha, Medhat Mikhail

    2017-01-01

    Background: The ideal intraoperative ventilation strategy in obese patients remains obscure. This prospective, randomized study was designed to evaluate the effect of pressure-controlled ventilation (PCV) before or after volume-controlled ventilation (VCV) on lung mechanics and hemodynamics variables in obese patients subjected to abdominoplasty operation. Patients and Methods: The study included forty patients with body mass index 30–45 kg/m2 subjected to abdominoplasty. All patients were randomly allocated in two groups after the induction of general anesthesia (twenty patients each), according to intraoperative ventilatory strategy. Group I (P-V): started with PCV until the plication of rectus muscle changes into VCV till the end of surgery. Group II (V-P): started with VCV until the plication of rectus muscle changes into PCV till the end of surgery. Lung mechanics, hemodynamics variables (heart rate and mean blood pressure), and arterial blood gases (ABGs) were recorded. Results: No significant difference in the hemodynamics and ABGs were recorded between the studied groups. The use of PCV after VCV induced the improvement of lung mechanics. Conclusion: Switching from VCV to PCV is preferred to improve intraoperative oxygenation and lung compliance without adverse hemodynamic effects in obese patients.

  10. [Nasopharyngeal myiasis during mechanical ventilation].

    Science.gov (United States)

    Yoshitomi, A; Sato, A; Suda, T; Chida, K

    1997-12-01

    We report a case of myiasis caused by Phaenicia sericata during mechanical ventilation. An 86-year-old woman with bronchiectasis was admitted to our hospital with severe respiratory failure. Treatment with mechanical ventilation and sedatives was initiated. On the 10th day of hospitalization, about 20 white larvae were found in the patient's oral or nasal cavities. The larvae were removed and identified as Phaenicia sericata. No mucosal injury was found in the patient's oral or nasal cavity by endoscopic examination. The patient died of multiple organ failure caused by sepsis that had no association with myiasis. From the clinical course and the fly's life cycle, it is considered that the fly laid eggs in the patient's oral or nasal cavity while she was sedated during mechanical ventilation. Myiasis can occur even in a hospital.

  11. A Double-Blind Randomized Clinical Trial Comparing the Effect of Neostigmine and Metoclopramide on Gastric Residual Volume of Mechanically Ventilated ICU Patients

    Science.gov (United States)

    Gholipour Baradari, Afshin; Alipour, Abbas; Firouzian, Abolfazl; Moarab, Laleh; Emami Zeydi, Amir

    2016-01-01

    Background: In critically ill patients, enteral feeding through the nasogastric tube is the method of choice for nutritional support. Gastrointestinal feeding intolerance and disturbed gastric emptying are common challenges in these patients. The aim of this study was to compare the effect of Neostigmine and Metoclopramide on gastric residual volume (GRV) in mechanically ventilated ICU patients. Methods: In a double blind, randomized clinical trial, a total of 60 mechanically ventilated ICU patients with GRV >120 mL (3 hours after the last gavage), were randomly assigned into two groups A and B. At baseline and 6 hours later, patients in group A and B received intravenous infusion of neostigmine in a dose of 2.5 mg and metoclopramide in a dose of 10 mg in 100 ml of normal saline, within 30 minutes. Patients’ gastric residual volumes were evaluated before the beginning of the intervention, and 3, 6, 9 and 12 hours after the intervention. Results: After adjusting of other variables (Sex, BMI and ICU stay period) generalized estimating equation (GEE) model revealed that neostigmine treatment increased odds of GRV improvement compare to metoclopramide group (Estimate 1.291, OR= 0.3.64, 95% CI 1.07-12.34). However there is a statistically significant time trend (within-subject differences or time effect) regardless of treatment groups (P<0.001). The median time from intervention to GRV improvement was 6 hours (95% CI 3.75-8.25) and 9 hours (95% CI 7.38-10.17) in neostigmine and metoclopramide groups, respectively. This difference was statistically significant (P<0.05). Conclusion: It seems that neostigmine is more effective than metoclopramide in reducing GRV and improving gastric emptying in mechanically ventilated ICU patients without significant complication and this protocol may be effective on the tolerance of enteral feeding in ICU patients. Further well-designed randomized clinical trials are needed. PMID:28077899

  12. Mechanical ventilation with high tidal volumes attenuates myocardial dysfunction by decreasing cardiac edema in a rat model of LPS-induced peritonitis

    Directory of Open Access Journals (Sweden)

    Smeding Lonneke

    2012-03-01

    Full Text Available Abstract Background Injurious mechanical ventilation (MV may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investigated the effects of MV with injuriously high tidal volumes on the myocardium in an animal model of sepsis. Methods Normal rats and intraperitoneal (i.p. lipopolysaccharide (LPS-treated rats were ventilated with low (6 ml/kg and high (19 ml/kg tidal volumes (Vt under general anesthesia. Non-ventilated animals served as controls. Mean arterial pressure (MAP, central venous pressure (CVP, cardiac output (CO and pulmonary plateau pressure (Pplat were measured. Ex vivo myocardial function was measured in isolated Langendorff-perfused hearts. Cardiac expression of endothelial vascular cell adhesion molecule (VCAM-1 and edema were measured to evaluate endothelial inflammation and leakage. Results MAP decreased after LPS-treatment and Vt-dependently, both independent of each other and with interaction. MV Vt-dependently increased CVP and Pplat and decreased CO. LPS-induced peritonitis decreased myocardial function ex vivo but MV attenuated systolic dysfunction Vt-dependently. Cardiac endothelial VCAM-1 expression was increased by LPS treatment independent of MV. Cardiac edema was lowered Vt-dependently by MV, particularly after LPS, and correlated inversely with systolic myocardial function parameters ex vivo. Conclusion MV attenuated LPS-induced systolic myocardial dysfunction in a Vt-dependent manner. This was associated with a reduction in cardiac edema following a lower transmural coronary venous outflow pressure during LPS-induced coronary inflammation.

  13. The impact of large tidal volume ventilation on the absorption of inhaled insulin in rabbits

    DEFF Research Database (Denmark)

    Petersen, Astrid Heide; Laursen, Torben; Ahrén, Bo;

    2007-01-01

    Previous studies have shown that ventilation patterns affect absorption of inhaled compounds. Thus, the aim of this study was to investigate the effect of large tidal volume ventilation (LTVV) on the absorption of inhaled insulin in rabbits. Mechanically ventilated rabbits were given human insuli...

  14. Iatrogenic pneumothorax related to mechanical ventilation

    OpenAIRE

    2014-01-01

    Pneumothorax is a potentially lethal complication associated with mechanical ventilation. Most of the patients with pneumothorax from mechanical ventilation have underlying lung diseases; pneumothorax is rare in intubated patients with normal lungs. Tension pneumothorax is more common in ventilated patients with prompt recognition and treatment of pneumothorax being important to minimize morbidity and mortality. Underlying lung diseases are associated with ventilator-related pneumothorax with...

  15. Comparison of actual tidal volume in neonatal lung model volume control ventilation using three ventilators.

    Science.gov (United States)

    Toyama, H; Endo, Y; Ejima, Y; Matsubara, M; Kurosawa, S

    2011-07-01

    In neonates, small changes in tidal volumes (V(T)) may lead to complications. Previous studies have shown a significant difference between ventilator-measured tidal volume and tidal volume delivered (actual V(T)). We evaluated the accuracy of three different ventilators to deliver small V(T) during volume-controlled ventilation. We tested Servo 300, 840 ventilator and Evita 4 Neoflow ventilators with lung models simulating normal and injured neonatal lung compliance models. Gas volume delivered from the ventilator into the test circuit (V(TV)) and actual V(T) to the test lung were measured using Ventrak respiration monitors at set V(T) (30 ml). The gas volume increase of the breathing circuit was then calculated. Tidal volumes of the SV300 and PB840 in both lung models were similar to the set V(T) and the actual tidal volumes in the injured model (20.7 ml and 19.8 ml, respectively) were significantly less than that in the normal model (27.4 ml and 23.4 ml). PB840 with circuit compliance compensation could not improve the actual V(T). V(TV) of the EV4N in the normal and the injured models (37.8 ml and 46.6 ml) were markedly increased compared with set V(T), and actual V(T) were similar to set V(T) in the normal and injured model (30.2 ml and 31.9 ml, respectively). EV4N measuring V(T) close to the lung could match actual V(T) to almost the same value as the set V(T) however the gas volume of the breathing circuit was increased. If an accurate value for the patient's actual V(T) is needed, this V(T) must be measured by a sensor located between the Y-piece and the tracheal tube.

  16. Mechanical ventilation with high tidal volumes attenuates myocardial dysfunction by decreasing cardiac edema in a rat model of LPS-induced peritonitis

    NARCIS (Netherlands)

    Smeding, Lonneke; Plotz, Frans B.; Lamberts, Regis R.; van der Laarse, Willem J.; Kneyber, Martin C. J.; Groeneveld, A. B. Johan

    2012-01-01

    Background: Injurious mechanical ventilation (MV) may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investiga

  17. Mechanical ventilation with high tidal volumes attenuates myocardial dysfunction by decreasing cardiac edema in a rat model of LPS-induced peritonitis

    NARCIS (Netherlands)

    Smeding, Lonneke; Plotz, Frans B.; Lamberts, Regis R.; van der Laarse, Willem J.; Kneyber, Martin C. J.; Groeneveld, A. B. Johan

    2012-01-01

    Background: Injurious mechanical ventilation (MV) may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investiga

  18. Humidification during invasive and noninvasive mechanical ventilation: 2012.

    Science.gov (United States)

    Restrepo, Ruben D; Walsh, Brian K

    2012-05-01

    We searched the MEDLINE, CINAHL, and Cochrane Library databases for articles published between January 1990 and December 2011. The update of this clinical practice guideline is based on 184 clinical trials and systematic reviews, and 10 articles investigating humidification during invasive and noninvasive mechanical ventilation. The following recommendations are made following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scoring system: 1. Humidification is recommended on every patient receiving invasive mechanical ventilation. 2. Active humidification is suggested for noninvasive mechanical ventilation, as it may improve adherence and comfort. 3. When providing active humidification to patients who are invasively ventilated, it is suggested that the device provide a humidity level between 33 mg H(2)O/L and 44 mg H(2)O/L and gas temperature between 34°C and 41°C at the circuit Y-piece, with a relative humidity of 100%. 4. When providing passive humidification to patients undergoing invasive mechanical ventilation, it is suggested that the HME provide a minimum of 30 mg H(2)O/L. 5. Passive humidification is not recommended for noninvasive mechanical ventilation. 6. When providing humidification to patients with low tidal volumes, such as when lung-protective ventilation strategies are used, HMEs are not recommended because they contribute additional dead space, which can increase the ventilation requirement and P(aCO(2)). 7. It is suggested that HMEs are not used as a prevention strategy for ventilator-associated pneumonia.

  19. Decisional responsibility for mechanical ventilation and weaning

    DEFF Research Database (Denmark)

    Rose, Louise; Blackwood, Bronagh; Egerod, Ingrid

    2011-01-01

    Optimal management of mechanical ventilation and weaning requires dynamic and collaborative decision making to minimize complications and avoid delays in the transition to extubation. In the absence of collaboration, ventilation decision making may be fragmented, inconsistent, and delayed. Our ob...... objective was to describe the professional group with responsibility for key ventilation and weaning decisions and to examine organizational characteristics associated with nurse involvement....

  20. Mechanical ventilation in patients subjected to extracorporeal membrane oxygenation (ECMO).

    Science.gov (United States)

    Sánchez, M L

    2017-02-07

    Mechanical ventilation (MV) is a crucial element in the management of acute respiratory distress syndrome (ARDS), because there is high level evidence that a low tidal volume of 6ml/kg (protective ventilation) improves survival. In these patients with refractory respiratory insufficiency, venovenous extracorporeal membrane oxygenation (ECMO) can be used. This salvage technique improves oxygenation, promotes CO2 clearance, and facilitates protective and ultraprotective MV, potentially minimizing ventilation-induced lung injury. Although numerous trials have investigated different ventilation strategies in patients with ARDS, consensus is lacking on the optimal MV settings during venovenous ECMO. Although the concept of "lung rest" was introduced years ago, there are no evidence-based guidelines on its use in application to MV in patients supported by ECMO. How MV in ECMO patients can promote lung recovery and weaning from ventilation is not clear. The purpose of this review is to describe the ventilation strategies used during venovenous ECMO in clinical practice.

  1. Heliox Improves Carbon Dioxide Removal during Lung Protective Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    Charlotte J. Beurskens

    2014-01-01

    Full Text Available Introduction. Helium is a noble gas with low density and increased carbon dioxide (CO2 diffusion capacity. This allows lower driving pressures in mechanical ventilation and increased CO2 diffusion. We hypothesized that heliox facilitates ventilation in patients during lung-protective mechanical ventilation using low tidal volumes. Methods. This is an observational cohort substudy of a single arm intervention study. Twenty-four ICU patients were included, who were admitted after a cardiac arrest and mechanically ventilated for 3 hours with heliox (50% helium; 50% oxygen. A fixed protective ventilation protocol (6 mL/kg was used, with prospective observation for changes in lung mechanics and gas exchange. Statistics was by Bonferroni post-hoc correction with statistical significance set at P<0.017. Results. During heliox ventilation, respiratory rate decreased (25±4 versus 23±5 breaths min−1, P=0.010. Minute volume ventilation showed a trend to decrease compared to baseline (11.1±1.9 versus 9.9±2.1 L min−1, P=0.026, while reducing PaCO2 levels (5.0±0.6 versus 4.5±0.6 kPa, P=0.011 and peak pressures (21.1±3.3 versus 19.8±3.2 cm H2O, P=0.024. Conclusions. Heliox improved CO2 elimination while allowing reduced minute volume ventilation in adult patients during protective mechanical ventilation.

  2. Cardiopulmonary interactions during mechanical ventilation in critically ill patients

    NARCIS (Netherlands)

    T.G.V. Cherpanath (Thomas); W.K. Lagrand (Wim); M.J. Schultz (Marcus); A.B.J. Groeneveld (Johan)

    2013-01-01

    textabstractCardiopulmonary interactions induced by mechan-ical ventilation are complex and only partly understood. Ap-plied tidal volumes and/or airway pressures largely mediate changes in right ventricular preload and afterload. Effects on left ventricular function are mostly secondary to changes

  3. Carbon dioxide production during mechanical ventilation

    DEFF Research Database (Denmark)

    Henneberg, S; Söderberg, D; Groth, T

    1987-01-01

    studied CO2 production (VCO2) and oxygen consumption (VO2) in mechanically ventilated ICU patients, where CO2 stores were altered by: a) changing minute ventilation by 15%, b) reducing body temperature, and c) changing the level of sedation. Expired gases went through a mixing chamber and were analyzed...

  4. Echocardiographic evaluation during weaning from mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Luciele Medianeira Schifelbain

    2011-01-01

    Full Text Available INTRODUCTION: Echocardiographic, electrocardiographic and other cardiorespiratory variables can change during weaning from mechanical ventilation. OBJECTIVES: To analyze changes in cardiac function, using Doppler echocardiogram, in critical patients during weaning from mechanical ventilation, using two different weaning methods: pressure support ventilation and T-tube; and comparing patient subgroups: success vs. failure in weaning. METHODS: Randomized crossover clinical trial including patients under mechanical ventilation for more than 48 h and considered ready for weaning. Cardiorespiratory variables, oxygenation, electrocardiogram and Doppler echocardiogram findings were analyzed at baseline and after 30 min in pressure support ventilation and T-tube. Pressure support ventilation vs. T-tube and weaning success vs. failure were compared using ANOVA and Student's t-test. The level of significance was p<0.05. RESULTS: Twenty-four adult patients were evaluated. Seven patients failed at the first weaning attempt. No echocardiographic or electrocardiographic differences were observed between pressure support ventilation and T-tube. Weaning failure patients presented increases in left atrium, intraventricular septum thickness, posterior wall thickness and diameter of left ventricle and shorter isovolumetric relaxation time. Successfully weaned patients had higher levels of oxygenation. CONCLUSION: No differences were observed between Doppler echocardiographic variables and electrocardiographic and other cardiorespiratory variables during pressure support ventilation and T-tube. However cardiac structures were smaller, isovolumetric relaxation time was larger, and oxygenation level was greater in successfully weaned patients

  5. Mechanical ventilation in neurological and neurosurgical patients.

    Science.gov (United States)

    Swain, Amlan; Bhagat, Hemant; Sahni, Neeru; Salunke, Pravin

    2016-01-01

    Approximately 20% of all patients requiring mechanical ventilation suffer from neurological dysfunction. It is imperative in the ventilatory management of such patients to have a thorough understanding of the disease pathology that may require institution of mechanical ventilation as well as in realizing its effects on the injured brain. These patients have unique challenges pertaining to the assessment and securing of the airway, maintenance of mechanical ventilation, as well as weaning and extubation readiness. This manuscript aims to present the current evidence in ventilatory management of the important subset of patients with neuronal injury. The indications for ventilatory management include both neurological and neurosurgical causes.

  6. Mechanisms of natural ventilation in livestock buildings

    DEFF Research Database (Denmark)

    Rong, Li; Bjerg, Bjarne Schmidt; Batzanas, Thomas;

    2016-01-01

    Studies on the mechanisms of natural ventilation in livestock buildings are reviewed and influences on discharge and pressure coefficients are discussed. Compared to studies conducted on buildings for human occupation and industrial buildings which focus on thermal comfort, ventilation systems......, indoor air quality, building physics and energy etc., our understanding of the mechanisms involved in natural ventilation of livestock buildings are still limited to the application of the orifice equation. It has been observed that the assumptions made for application of the orifice equation...... are not valid for wind-induced cross ventilation through large openings. This review identifies that the power balance model, the concept of stream tube and the local dynamic similarity model has helped in the fundamental understanding of wind-induced natural ventilation in buildings for human occupation...

  7. New modes of assisted mechanical ventilation.

    Science.gov (United States)

    Suarez-Sipmann, F

    2014-05-01

    Recent major advances in mechanical ventilation have resulted in new exciting modes of assisted ventilation. Compared to traditional ventilation modes such as assisted-controlled ventilation or pressure support ventilation, these new modes offer a number of physiological advantages derived from the improved patient control over the ventilator. By implementing advanced closed-loop control systems and using information on lung mechanics, respiratory muscle function and respiratory drive, these modes are specifically designed to improve patient-ventilator synchrony and reduce the work of breathing. Depending on their specific operational characteristics, these modes can assist spontaneous breathing efforts synchronically in time and magnitude, adapt to changing patient demands, implement automated weaning protocols, and introduce a more physiological variability in the breathing pattern. Clinicians have now the possibility to individualize and optimize ventilatory assistance during the complex transition from fully controlled to spontaneous assisted ventilation. The growing evidence of the physiological and clinical benefits of these new modes is favoring their progressive introduction into clinical practice. Future clinical trials should improve our understanding of these modes and help determine whether the claimed benefits result in better outcomes.

  8. Secretion management in the mechanically ventilated patient

    OpenAIRE

    Mantellini E.; Perrero L.; Provenzano G.; Petrozzino S.

    2012-01-01

    Purpose: the aim of this work is to highlight the importance of a correct management of the secretions in the patient submitted to mechanical ventilation (MV). Methods: analysis of the current bibliography related to respiratory infections and secretion in patients with mechanically ventilation. We focus on the use of in-ex suflator achine (cough machine) associated with High Frequency Chest Wall Oscillation (HFCWO).Results: we observe a reduction of pulmonary infection and a better managemen...

  9. Humidification of inspired gases during mechanical ventilation.

    Science.gov (United States)

    Gross, J L; Park, G R

    2012-04-01

    Humidification of inspired gas is mandatory for all mechanically ventilated patients to prevent secretion retention, tracheal tube blockage and adverse changes occurring to the respiratory tract epithelium. However, the debate over "ideal" humidification continues. Several devices are available that include active and passive heat and moisture exchangers and hot water humidifiers Each have their advantages and disadvantages in mechanically ventilated patients. This review explores each device in turn and defines their role in clinical practice.

  10. Mechanical ventilation and respiratory mechanics during equine anesthesia.

    Science.gov (United States)

    Moens, Yves

    2013-04-01

    The mechanical ventilation of horses during anesthesia remains a crucial option for optimal anesthetic management, if the possible negative cardiovascular side effects are managed, because this species is prone to hypercapnia and hypoxemia. The combined use of capnography and pitot-based spirometry provide complementary information on ventilation and respiratory mechanics, respectively. This facilitates management of mechanical ventilation in conditions of changing respiratory system compliance (ie, laparoscopy) and when investigating new ventilatory strategies including alveolar recruitment maneuvers and optimization of positive expiratory pressure.

  11. Links between the mechanics of ventilation and spine stability.

    Science.gov (United States)

    Wang, Simon; McGill, Stuart M

    2008-05-01

    Spine stability is ensured through isometric coactivation of the torso muscles; however, these same muscles are used cyclically to assist ventilation. Our objective was to investigate this apparent paradoxical role (isometric contraction for stability or rhythmic contraction for ventilation) of some selected torso muscles that are involved in both ventilation and support of the spine. Eight, asymptomatic, male subjects provided data on low back moments, motion, muscle activation, and hand force. These data were input to an anatomically detailed, biologically driven model from which spine load and a lumbar spine stability index was obtained. Results revealed that subjects entrained their torso stabilization muscles to breathe during demanding ventilation tasks. Increases in lung volume and back extensor muscle activation coincided with increases in spine stability, whereas declines in spine stability were observed during periods of low lung inflation volume and simultaneously low levels of torso muscle activation. As a case study, aberrant ventilation motor patterns (poor muscle entrainment), seen in one subject, compromised spine stability. Those interested in rehabilitation of patients with lung compromise and concomitant back troubles would be assisted with knowledge of the mechanical links between ventilation during tasks that impose spine loading.

  12. Prophylactic protective ventilation: lower tidal volumes for all critically ill patients?

    Science.gov (United States)

    Lellouche, Francois; Lipes, Jed

    2013-01-01

    High tidal volumes have historically been recommended for mechanically ventilated patients during general anesthesia. High tidal volumes have been shown to increase morbidity and mortality in patients suffering from acute respiratory distress syndrome (ARDS). Barriers exist in implementing a tidal volume reduction strategy related to the inherent difficulty in changing one's practice patterns, to the current need to individualize low tidal volume settings only for a specific subgroup of mechanically ventilated patients (i.e., ARDS patients), the difficulty in determining the predicated body weight (requiring the patient's height and a complex formula). Consequently, a protective ventilation strategy is often under-utilized as a therapeutic option, even in ARDS. Recent data supports the generalization of this strategy prophylactically to almost all mechanically ventilated patients beginning immediately following intubation. Using tools to rapidly and reliably determine the predicted body weight (PBW), as well as the use of automated modes of ventilation are some of the potential solutions to facilitate the practice of protective ventilation and to finally ventilate our patients' lungs in a more gentle fashion to help prevent ARDS.

  13. Effect of low tidal volume ventilation on lung function and inflammation in mice

    Directory of Open Access Journals (Sweden)

    Goldmann Torsten

    2010-04-01

    Full Text Available Abstract Background A large number of studies have investigated the effects of high tidal volume ventilation in mouse models. In contrast data on very short term effects of low tidal volume ventilation are sparse. Therefore we investigated the functional and structural effects of low tidal volume ventilation in mice. Methods 38 Male C57/Bl6 mice were ventilated with different tidal volumes (Vt 5, 7, and 10 ml/kg without or with application of PEEP (2 cm H2O. Four spontaneously breathing animals served as controls. Oxygen saturation and pulse rate were monitored. Lung function was measured every 5 min for at least 30 min. Afterwards lungs were removed and histological sections were stained for measurement of infiltration with polymorphonuclear leukocytes (PMN. Moreover, mRNA expression of macrophage inflammatory protein (MIP-2 and tumor necrosis factor (TNFα in the lungs was quantified using real time PCR. Results Oxygen saturation did not change significantly over time of ventilation in all groups (P > 0.05. Pulse rate dropped in all groups without PEEP during mechanical ventilation. In contrast, in the groups with PEEP pulse rate increased over time. These effects were not statistically significant (P > 0.05. Tissue damping (G and tissue elastance (H were significantly increased in all groups after 30 min of ventilation (P 0.05. Mechanical ventilation significantly increased infiltration of the lungs with PMN (P Conclusions Our data show that very short term mechanical ventilation with lower tidal volumes than 10 ml/kg did not reduce inflammation additionally. Formation of atelectasis and inadequate oxygenation with very low tidal volumes may be important factors. Application of PEEP attenuated inflammation.

  14. Recurrent recruitment manoeuvres improve lung mechanics and minimize lung injury during mechanical ventilation of healthy mice.

    Directory of Open Access Journals (Sweden)

    Lucy Kathleen Reiss

    Full Text Available INTRODUCTION: Mechanical ventilation (MV of mice is increasingly required in experimental studies, but the conditions that allow stable ventilation of mice over several hours have not yet been fully defined. In addition, most previous studies documented vital parameters and lung mechanics only incompletely. The aim of the present study was to establish experimental conditions that keep these parameters within their physiological range over a period of 6 h. For this purpose, we also examined the effects of frequent short recruitment manoeuvres (RM in healthy mice. METHODS: Mice were ventilated at low tidal volume V(T = 8 mL/kg or high tidal volume V(T = 16 mL/kg and a positive end-expiratory pressure (PEEP of 2 or 6 cm H(2O. RM were performed every 5 min, 60 min or not at all. Lung mechanics were followed by the forced oscillation technique. Blood pressure (BP, electrocardiogram (ECG, heart frequency (HF, oxygen saturation and body temperature were monitored. Blood gases, neutrophil-recruitment, microvascular permeability and pro-inflammatory cytokines in bronchoalveolar lavage (BAL and blood serum as well as histopathology of the lung were examined. RESULTS: MV with repetitive RM every 5 min resulted in stable respiratory mechanics. Ventilation without RM worsened lung mechanics due to alveolar collapse, leading to impaired gas exchange. HF and BP were affected by anaesthesia, but not by ventilation. Microvascular permeability was highest in atelectatic lungs, whereas neutrophil-recruitment and structural changes were strongest in lungs ventilated with high tidal volume. The cytokines IL-6 and KC, but neither TNF nor IP-10, were elevated in the BAL and serum of all ventilated mice and were reduced by recurrent RM. Lung mechanics, oxygenation and pulmonary inflammation were improved by increased PEEP. CONCLUSIONS: Recurrent RM maintain lung mechanics in their physiological range during low tidal volume ventilation of healthy mice by

  15. Secretion management in the mechanically ventilated patient

    Directory of Open Access Journals (Sweden)

    Mantellini E.

    2012-01-01

    Full Text Available Purpose: the aim of this work is to highlight the importance of a correct management of the secretions in the patient submitted to mechanical ventilation (MV. Methods: analysis of the current bibliography related to respiratory infections and secretion in patients with mechanically ventilation. We focus on the use of in-ex suflator achine (cough machine associated with High Frequency Chest Wall Oscillation (HFCWO.Results: we observe a reduction of pulmonary infection and a better management of bronchial secretion in patient undergone to the use of in-ex suflator machine (cough machine associated with High Frequency Chest Wall Oscillation (HFCWO.Conclusions: the correct approach to patients submitted to mechanical ventilation (MV expect the use of High Frequency Chest Wall Oscillation (HFCWO (VEST and in-ex suflator machine (cough machine to decrease pulmonary infection thank to a reduction of permanence of bronchial secretions in the lungs .

  16. Recent innovations in mechanical ventilator support

    Directory of Open Access Journals (Sweden)

    Manu Chopra

    2014-01-01

    Full Text Available Mechanical ventilation as a means to provide basic lifesaving ventilatory support has grown leaps and bounds in the recent years. The basic modes of ventilation have seen a sea change and in addition other innovative techniques have been developed to prevent lung injury, ease of weaning and improve patient comfort. These modes and techniques though easily available are not adequately utilized for benefits of patient usually due to lack of knowledge about them. This article reviews some of these newer modes and innovations in mechanical ventilatory support.

  17. Early Mobilization of Mechanically Ventilated Patients.

    Science.gov (United States)

    Hruska, Pam

    2016-12-01

    Critically ill patients requiring mechanical ventilation are least likely to be mobilized and, as a result, are at-risk for prolonged complications from weakness. The use of bed rest and sedation when caring for mechanically ventilated patients is likely shaped by historical practice; however, this review demonstrates early mobilization, with little to no sedation, is possible and safe. Assessing readiness for mobilization in context of progressing patients from passive to active activities can lead to long-term benefits and has been achievable with resource-efficient implementations and team work.

  18. Nonassociative learning promotes respiratory entrainment to mechanical ventilation.

    Directory of Open Access Journals (Sweden)

    Shawna M MacDonald

    Full Text Available BACKGROUND: Patient-ventilator synchrony is a major concern in critical care and is influenced by phasic lung-volume feedback control of the respiratory rhythm. Routine clinical application of positive end-expiratory pressure (PEEP introduces a tonic input which, if unopposed, might disrupt respiratory-ventilator entrainment through sustained activation of the vagally-mediated Hering-Breuer reflex. We suggest that this potential adverse effect may be averted by two differentiator forms of nonassociative learning (habituation and desensitization of the Hering-Breuer reflex via pontomedullary pathways. METHODOLOGY/PRINCIPAL FINDINGS: We tested these hypotheses in 17 urethane-anesthetized adult Sprague-Dawley rats under controlled mechanical ventilation. Without PEEP, phrenic discharge was entrained 1:1 to the ventilator rhythm. Application of PEEP momentarily dampened the entrainment to higher ratios but this effect was gradually adapted by nonassociative learning. Bilateral electrolytic lesions of the pneumotaxic center weakened the adaptation to PEEP, whereas sustained stimulation of the pneumotaxic center weakened the entrainment independent of PEEP. In all cases, entrainment was abolished after vagotomy. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate an important functional role for pneumotaxic desensitization and extra-pontine habituation of the Hering-Breuer reflex elicited by lung inflation: acting as buffers or high-pass filters against tonic vagal volume input, these differentiator forms of nonassociative learning help to restore respiratory-ventilator entrainment in the face of PEEP. Such central sites-specific habituation and desensitization of the Hering-Breuer reflex provide a useful experimental model of nonassociative learning in mammals that is of particular significance in understanding respiratory rhythmogenesis and coupled-oscillator entrainment mechanisms, and in the clinical management of mechanical ventilation in

  19. Indirect Calorimetry in Mechanically Ventilated Patients

    DEFF Research Database (Denmark)

    Allingstrup, Matilde Jo; Kondrup, Jens; Perner, Anders

    2017-01-01

    BACKGROUND AND AIMS: The 2 currently available indirect calorimeters, CCM Express Indirect Calorimeter (MedGraphics, St Paul, MN) and Quark RMR ICU Indirect Calorimeter (COSMED, Rome, Italy), have not been validated against a gold standard in mechanically ventilated patients. Our aim was to do so...

  20. Comparative Study of pressure-control ventilation and volume-control ventilation in treating traumatic acute respiratory distress syndrome

    Institute of Scientific and Technical Information of China (English)

    杨云梅; 黄卫东; 沈美亚; 徐哲荣

    2005-01-01

    Objective: To observe the clinical therapeutic effect and side effect of pressure-control ventilation (PCV) on traumatic acute respiratory distress syndrome (ARDS) compared with volume-control ventilation (VCV).Methods: Forty patients with traumatic ARDS were hospitalized in our department from June 1996 to December 2002. Twenty were treated with PCV (PCV group) and 20 with VCV (VCV group). The changes of the peak inflating pressure and the mean pressure of the airway were observed at the very beginning of the mechanical ventilation and the following 12 and 24 hours, respectively. The transcutaneous saturation of oxygen pressure, the pressure of oxygen in artery, the mean blood pressure, the central venous pressure, the heart rate and the incidence of the pressure injury were also monitored before ventilation and 12 hours after ventilation.Results: The pressure of oxygen in artery, the transcutaneous saturation of oxygen pressure, the heart rate and the respiratory rate in the PCV group were obviously improved after ventilation treatment. The peak inflating pressure, the mean pressure of the airway and the central venous pressure in the PCV group were lower than in the VCV group. The incidence of pressure injury was 0 in the PCV group while 10% in the VCV group. Conclusions: The clinical effect of PCV on traumatic ARDS is better and the incidence rate of pressure injury is lower than that of VCV. PCV has minimal effects on the hemodynamics.

  1. Respiratory care year in review 2010: part 2. Invasive mechanical ventilation, noninvasive ventilation, pediatric mechanical ventilation, aerosol therapy.

    Science.gov (United States)

    Macintyre, Neil R; Nava, Stefano; Diblasi, Robert M; Restrepo, Ruben D; Hess, Dean R

    2011-05-01

    The purpose of this paper is to review the recent literature related to invasive mechanical ventilation, NIV, pediatric mechanical ventilation, and aerosol therapy. Topics covered related to invasive mechanical ventilation topics include the role of PEEP in providing lung protection during mechanical ventilation, unconventional modes for severe hypoxemia, and strategies to improve patient-ventilator interactions. Topics covered related to NIV include real-life NIV use, NIV and extubation failure, and NIV and pandemics. For pediatric mechanical ventilation, the topics addressed are NIV, invasive respiratory support, and inhaled nitric oxide. Topics covered related to aerosol therapy include short-acting β-adrenergic agents, long-acting β-adrenergic agents, long-acting antimuscarinic agents, inhaled corticosteroid therapy, phosphodiesterase type 4 (PDE4) inhibitors, long-acting β-adrenergic plus inhaled corticosteroid, long-acting antimuscarinic plus inhaled corticosteroid, nebulized hypertonic saline, inhaled mannitol, and inhaled antibiotic therapy. These topics were chosen and reviewed in a manner that is most likely to have interest to the readers of Respiratory Care.

  2. [Monitorization of respiratory mechanics in the ventilated patient].

    Science.gov (United States)

    García-Prieto, E; Amado-Rodríguez, L; Albaiceta, G M

    2014-01-01

    Monitoring during mechanical ventilation allows the measurement of different parameters of respiratory mechanics. Accurate interpretation of these data can be useful for characterizing the situation of the different components of the respiratory system, and for guiding ventilator settings. In this review, we describe the basic concepts of respiratory mechanics, their interpretation, and their potential use in fine-tuning mechanical ventilation.

  3. Experimental study of acute lung injury induced by different tidal volume ventilation in rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-ri; DU Yong-cheng; JIANG Hong-ying; XU Jian-ying; XU Yong-jian

    2005-01-01

    @@ Mechanical ventilation (MV) is a dual blade sward which if misused could lead to lung injury, called ventilator induced lung injury (VILI). Pathogenesis of VILI is very complex with various manifestations, which is the focus in MV field in recent years.1 In our research, the rats were ventilated with different tidal volume, then the pathological changes of the lungs were observed under macroscopy, light and electronic microscope, and various laboratory tests in blood and bronchoalveolar lavage fluid (BALF) were also carried out in order to probe further the pathologic characteristics and the pathogenesis of VILI.

  4. Management of critically ill patients receiving noninvasive and invasive mechanical ventilation in the emergency department

    Directory of Open Access Journals (Sweden)

    Rose L

    2012-03-01

    Full Text Available Louise RoseLawrence S Bloomberg Faculty of Nursing, University of Toronto, Toronto, Ontario, CanadaAbstract: Patients requiring noninvasive and invasive ventilation frequently present to emergency departments, and may remain for prolonged periods due to constrained critical care services. Emergency clinicians often do not receive the same education on management of mechanical ventilation or have similar exposure to these patients as do their critical care colleagues. The aim of this review was to synthesize the evidence on management of patients requiring noninvasive and invasive ventilation in the emergency department including indications, clinical applications, monitoring priorities, and potential complications. Noninvasive ventilation is recommended for patients with acute exacerbation of chronic obstructive pulmonary disease or cardiogenic pulmonary edema. Less evidence supports its use in asthma and other causes of acute respiratory failure. Use of noninvasive ventilation in the prehospital setting is relatively new, and some evidence suggests benefit. Monitoring priorities for noninvasive ventilation include response to treatment, respiratory and hemodynamic stability, noninvasive ventilation tolerance, detection of noninvasive ventilation failure, and identification of air leaks around the interface. Application of injurious ventilation increases patient morbidity and mortality. Lung-protective ventilation with low tidal volumes based on determination of predicted body weight and control of plateau pressure has been shown to reduce mortality in patients with acute respiratory distress syndrome, and some evidence exists to suggest this strategy should be used in patients without lung injury. Monitoring of the invasively ventilated patient should focus on assessing response to mechanical ventilation and other interventions, and avoiding complications, such as ventilator-associated pneumonia. Several key aspects of management of noninvasive

  5. Regional tidal lung strain in mechanically ventilated normal lungs.

    Science.gov (United States)

    Paula, Luis Felipe; Wellman, Tyler J; Winkler, Tilo; Spieth, Peter M; Güldner, Andreas; Venegas, Jose G; Gama de Abreu, Marcelo; Carvalho, Alysson R; Vidal Melo, Marcos F

    2016-12-01

    Parenchymal strain is a key determinant of lung injury produced by mechanical ventilation. However, imaging estimates of volumetric tidal strain (ε = regional tidal volume/reference volume) present substantial conceptual differences in reference volume computation and consideration of tidally recruited lung. We compared current and new methods to estimate tidal volumetric strains with computed tomography, and quantified the effect of tidal volume (VT) and positive end-expiratory pressure (PEEP) on strain estimates. Eight supine pigs were ventilated with VT = 6 and 12 ml/kg and PEEP = 0, 6, and 12 cmH2O. End-expiratory and end-inspiratory scans were analyzed in eight regions of interest along the ventral-dorsal axis. Regional reference volumes were computed at end-expiration (with/without correction of regional VT for intratidal recruitment) and at resting lung volume (PEEP = 0) corrected for intratidal and PEEP-derived recruitment. All strain estimates demonstrated vertical heterogeneity with the largest tidal strains in middependent regions (P < 0.01). Maximal strains for distinct estimates occurred at different lung regions and were differently affected by VT-PEEP conditions. Values consistent with lung injury and inflammation were reached regionally, even when global measurements were below critical levels. Strains increased with VT and were larger in middependent than in nondependent lung regions. PEEP reduced tidal-strain estimates referenced to end-expiratory lung volumes, although it did not affect strains referenced to resting lung volume. These estimates of tidal strains in normal lungs point to middependent lung regions as those at risk for ventilator-induced lung injury. The different conditions and topography at which maximal strain estimates occur allow for testing the importance of each estimate for lung injury.

  6. Prolonged propofol infusion for mechanically ventilated children.

    Science.gov (United States)

    Sasabuchi, Y; Yasunaga, H; Matsui, H; Lefor, A K; Fushimi, K

    2016-04-01

    We retrospectively analysed 30-day mortality and duration of intubation for 8016 children ventilated for three or more days, sedated with midazolam (n = 7716) or propofol (n = 300). We matched the propensity scores of 263 pairs of children. The propensity-matched 30-day mortality (95% CI) was similar: 17/263 (6.5%) with midazolam vs. 24/263 (9.1%) with propofol, p = 0.26. Weaning from mechanical ventilation of children sedated with midazolam was slower than weaning of children sedated with propofol, subhazard ratio (95% CI) 1.43 (1.18-1.73), p < 0.001. © 2016 The Association of Anaesthetists of Great Britain and Ireland.

  7. Effect of high volume mechanical ventilation on radiation-induced lung toxicity in rats%机械通气对大鼠照射后肺组织及细胞凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    金胜; 陈军; 叶繁; 冯丹

    2015-01-01

    Objective To evaluate the effects of mechanical ventilation on radiation induced lung injuries of apoptosis,acute inflammation,and oxidative stress by establishing a rat mechanical ventilation model and animal model.Methods Totally 40 male Sprague-Dawley(SD) rats were randomly divided into 4 groups with 10 rats in each group:control,radiation alone,high tidal volume ventilation,and high tidal volume ventilation following by radiation.After treatment,the pathological changes in lung tissue were observed,NF-κB activity was detected by electrophoretic mobility shift assay (EMSA),the expression of NF-κB subunit P65 protein level in lung cell nucleus was detected by Western blot,and the apoptosis of lung cells was detected by terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) method.The wet to dry weight ratio (W/D) of lung,myeloperoxidase (MPO),malondialdehyde (MDA) and superoxide dismutase (SOD) were detected.In addition,the total protein and white blood cell number in lung lavage fluid were also measured.Results Compared to the control,the acute lung injury (ALI) score,W/D ratio,MPO activity,total protein level,white blood cell number,apoptosis index (AI),lung tissue MDA,NF-κB activity and P65 protein expression were increased significantly (q =0.000 32-0.004 81,P <0.05),while SOD values was decreased significantly (q =0.000 18-0.002 53,P <0.01),in other three groups.Compared with radiation and high tidal volume ventilation group,the above indexes were significantly higher (q =0.004 3-0.022 6,P < 0.05) but the SOD value was significantly lower (q =0.002 9-0.008 3,P < 0.05) than those in the high tidal volume ventilation plus radiation group.Conclusions High tidal volume ventilation delivered to the radiation group produced more transparent ventilator-induced lung injury (VILI) than the high tidal volume ventilation alone induced VILI including permeable pulmonary edema,acute inflammation,oxidative stress and apoptosis in

  8. Collective fluid mechanics of honeybee nest ventilation

    Science.gov (United States)

    Gravish, Nick; Combes, Stacey; Wood, Robert J.; Peters, Jacob

    2014-11-01

    Honeybees thermoregulate their brood in the warm summer months by collectively fanning their wings and creating air flow through the nest. During nest ventilation workers flap their wings in close proximity in which wings continuously operate in unsteady oncoming flows (i.e. the wake of neighboring worker bees) and near the ground. The fluid mechanics of this collective aerodynamic phenomena are unstudied and may play an important role in the physiology of colony life. We have performed field and laboratory observations of the nest ventilation wing kinematics and air flow generated by individuals and groups of honeybee workers. Inspired from these field observations we describe here a robotic model system to study collective flapping wing aerodynamics. We microfabricate arrays of 1.4 cm long flapping wings and observe the air flow generated by arrays of two or more fanning robotic wings. We vary phase, frequency, and separation distance among wings and find that net output flow is enhanced when wings operate at the appropriate phase-distance relationship to catch shed vortices from neighboring wings. These results suggest that by varying position within the fanning array honeybee workers may benefit from collective aerodynamic interactions during nest ventilation.

  9. Patient experiences during awake mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Danille Prime

    2016-02-01

    Full Text Available Background: Sedation practices in an ICU have shifted significantly in the past 20 years toward the use of minimizing sedation in mechanically ventilated patients. While minimizing sedation is clearly in the best interest of patients, data are lacking about how this approach affects patients’ experiences. Methods: We interviewed mechanically ventilated patients receiving minimal sedation, over a 6-month period in an ICU, in order to explore their emotional, comfort, and communication experiences. Their responses were compared with the responses of their available family members regarding their attitudes and perceptions of the patients’ experiences. Results: Seventy-five percent of the patients agreed or strongly agreed that they experienced pain, and 50% agreed or strongly agreed that they were comfortable. Half of the patients agreed or strongly agreed that they preferred to be kept awake. Five patients (31% indicated that they were frustrated while 17 relatives (89% agreed or strongly agreed that the patients were frustrated. When controlling for age and gender of respondents, family members perceived higher levels of patient pain (least square [LS] mean [95% CI]: 4.2 [3.7, 4.7] vs. 3.1 [2.5, 3.8]; p=0.022, frustration (LS mean [95% CI]: 4.2 [3.7, 4.6] vs. 3.2 [2.6, 3.9]; p=0.031, and adequate communication with nurses and doctors (LS mean [95% CI]: 3.9 [3.5, 4.4] vs. 3.1 [2.4, 3.7]; p=0.046 than the patients themselves. Conclusion: Patients tolerated minimal sedation without significant frustration while mechanically ventilated despite experiencing discomfort. Patient and family member perceptions of the patient experience may differ, especially in regards to pain and frustration. The use of a communication tool can facilitate understanding of patient experiences and preferences.

  10. The influence of music during mechanical ventilation and weaning from mechanical ventilation: A review.

    Science.gov (United States)

    Hetland, Breanna; Lindquist, Ruth; Chlan, Linda L

    2015-01-01

    Mechanical ventilation (MV) causes many distressing symptoms. Weaning, the gradual decrease in ventilator assistance leading to termination of MV, increases respiratory effort, which may exacerbate symptoms and prolong MV. Music, a non-pharmacological intervention without side effects may benefit patients during weaning from mechanical ventilatory support. A narrative review of OVID Medline, PsychINFO, and CINAHL databases was conducted to examine the evidence for the use of music intervention in MV and MV weaning. Music intervention had a positive impact on ventilated patients; 16 quantitative and 2 qualitative studies were identified. Quantitative studies included randomized clinical trials (10), case controls (3), pilot studies (2) and a feasibility study. Evidence supports music as an effective intervention that can lesson symptoms related to MV and promote effective weaning. It has potential to reduce costs and increase patient satisfaction. However, more studies are needed to establish its use during MV weaning. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Design Features of Modern Mechanical Ventilators.

    Science.gov (United States)

    MacIntyre, Neil

    2016-12-01

    A positive-pressure breath ideally should provide a VT that is adequate for gas exchange and appropriate muscle unloading while minimizing any risk for injury or discomfort. The latest generation of ventilators uses sophisticated feedback systems to sculpt positive-pressure breaths according to patient effort and respiratory system mechanics. Currently, however, these new control strategies are not totally closed-loop systems. This is because the automatic input variables remain limited, some clinician settings are still required, and the specific features of the perfect breath design still are not entirely clear. Despite these limitations, there are some rationale for many of these newer feedback features.

  12. Reduction in adverse effects of mechanical ventilation in rabbits with acute respiratory failure by treatment with extracorporeal CO2 removal and a large fluid volume of diluted surfactant

    NARCIS (Netherlands)

    Plotz, FB; Mook, PH; Jansen, NJG; Oetomo, SB; Wildevuur, CRH

    1997-01-01

    The long-term outcome of infants with severe respiratory distress syndrome can be improved by optimizing surfactant therapy and minimizing the risk for pulmonary barovolutrauma and oxygen toxicity. The authors hypothesized that this may be achieved with low frequency ventilation and extracorporeal C

  13. NanoClusters Enhance Drug Delivery in Mechanical Ventilation

    Science.gov (United States)

    Pornputtapitak, Warangkana

    The overall goal of this thesis was to develop a dry powder delivery system for patients on mechanical ventilation. The studies were divided into two parts: the formulation development and the device design. The pulmonary system is an attractive route for drug delivery since the lungs have a large accessible surface area for treatment or drug absorption. For ventilated patients, inhaled drugs have to successfully navigate ventilator tubing and an endotracheal tube. Agglomerates of drug nanoparticles (also known as 'NanoClusters') are fine dry powder aerosols that were hypothesized to enable drug delivery through ventilator circuits. This Thesis systematically investigated formulations of NanoClusters and their aerosol performance in a conventional inhaler and a device designed for use during mechanical ventilation. These engineered powders of budesonide (NC-Bud) were delivered via a MonodoseRTM inhaler or a novel device through commercial endotracheal tubes, and analyzed by cascade impaction. NC-Bud had a higher efficiency of aerosol delivery compared to micronized stock budesonide. The delivery efficiency was independent of ventilator parameters such as inspiration patterns, inspiration volumes, and inspiration flow rates. A novel device designed to fit directly to the ventilator and endotracheal tubing connections and the MonodoseRTM inhaler showed the same efficiency of drug delivery. The new device combined with NanoCluster formulation technology, therefore, allowed convenient and efficient drug delivery through endotracheal tubes. Furthermore, itraconazole (ITZ), a triazole antifungal agent, was formulated as a NanoCluster powder via milling (top-down process) or precipitation (bottom-up process) without using any excipients. ITZ NanoClusters prepared by wet milling showed better aerosol performance compared to micronized stock ITZ and ITZ NanoClusters prepared by precipitation. ITZ NanoClusters prepared by precipitation methods also showed an amorphous state

  14. Advanced lung ventilation system (ALVS) with linear respiratory mechanics assumption for waveform optimization of dual-controlled ventilation.

    Science.gov (United States)

    Montecchia, F; Guerrisi, M; Canichella, A

    2007-03-01

    The present paper describes the functional features of an advanced lung ventilation system (ALVS) properly designed for the optimization of conventional dual-controlled ventilation (DCV), i.e. with pressure-controlled ventilation with ensured tidal or minute volume. Considering the particular clinical conditions of patients treated with controlled ventilation the analysis and synthesis of ALVS control have been performed assuming a linear respiratory mechanics. Moreover, new airways pressure waveforms with more physiological shape can be tested on simulators of respiratory system in order to evaluate their clinical application. This is obtained through the implementation of a compensation procedure making the desired airways pressure waveform independent on patient airways resistance and lung compliance variations along with a complete real-time monitoring of respiratory system parameters leading the ventilator setting. The experimental results obtained with a lung simulator agree with the theoretical ones and show that ALVS performance is useful for the research activity aiming at the improvement of both diagnostic evaluation and therapeutic outcome relative to mechanical ventilation treatments.

  15. Medida da freqüência respiratória e do volume corrente para prever a falha na extubação de recém-nascidos de muito baixo peso em ventilação mecânica Evaluation of respiratory rate and tidal volume to predict extubation failure in mechanically ventilated very low birth weight infants

    Directory of Open Access Journals (Sweden)

    Josy Davidson

    2008-03-01

    Full Text Available OBJETIVO: Verificar se a freqüência respiratória (FR, o volume corrente (VC e a relação FR/VC poderiam prever a falha na extubação em recém-nascidos de muito baixo peso submetidos à ventilação mecânica. MÉTODOS: Estudo prospectivo, observacional, de recém-nascidos com idade gestacional OBJECTIVE: To verify if respiratory rate (RR, tidal volume (TV and respiratory rate and tidal volume ratio (RR/TV could predict extubation failure in very low birth weight infants submitted to mechanical ventilation. METHODS: This prospective observational study enrolled newborn infants with gestational age <37 weeks and birth weight <1,500g, mechanically ventilated from birth during 48 hours to 30 days and thought to be ready for extubation. As soon as the physicians decided for extubation, the neonates received endotracheal continuous positive airway pressure (CPAP for 10 minutes while spontaneous RR, TV and RR/TV were measured using a fixed-orifice pneumotachograph positioned between the endotracheal tube and the ventilator circuit. Thereafter, the neonates were extubated to nasal CPAP. Extubation failure was defined as the need for reintubation within 48 hours. RESULTS: Of the 35 studied infants, 20 (57% were successfully extubated and 15 (43% required reintubation. RR and RR/TV before extubation had a trend to be higher in unsuccessfully extubated infants. TV was similar in both groups. Sensitivity and specificity of these parameters as predictors of extubation failure were 50 and 67% respectively for RR, 40 and 67% for TV and 40 and 73% for RR/TV. CONCLUSIONS: RR, TV and RR/TV showed low sensitivity and specificity to predict extubation failure in mechanically ventilated very low birth weight infants.

  16. Evaluation of Mechanical Ventilator Use with Liquid Oxygen Systems

    Science.gov (United States)

    2017-02-22

    AFRL-SA-WP-SR-2017-0006 Evaluation of Mechanical Ventilator Use with Liquid Oxygen Systems Thomas Blakeman, MSc, RRT; Dario...To) August 2014 – September 2016 4. TITLE AND SUBTITLE Evaluation of Mechanical Ventilator Use with Liquid Oxygen Systems 5a. CONTRACT NUMBER...Cleared, 88PA, Case # 2016-6491, 16 Dec 2016. 14. ABSTRACT Mechanical ventilators coupled with portable liquid oxygen (LOX) systems are critical

  17. Management and outcome of mechanically ventilated patients after cardiac arrest.

    Science.gov (United States)

    Sutherasan, Yuda; Peñuelas, Oscar; Muriel, Alfonso; Vargas, Maria; Frutos-Vivar, Fernando; Brunetti, Iole; Raymondos, Konstantinos; D'Antini, Davide; Nielsen, Niklas; Ferguson, Niall D; Böttiger, Bernd W; Thille, Arnaud W; Davies, Andrew R; Hurtado, Javier; Rios, Fernando; Apezteguía, Carlos; Violi, Damian A; Cakar, Nahit; González, Marco; Du, Bin; Kuiper, Michael A; Soares, Marco Antonio; Koh, Younsuck; Moreno, Rui P; Amin, Pravin; Tomicic, Vinko; Soto, Luis; Bülow, Hans-Henrik; Anzueto, Antonio; Esteban, Andrés; Pelosi, Paolo

    2015-05-08

    The aim of this study was to describe and compare the changes in ventilator management and complications over time, as well as variables associated with 28-day hospital mortality in patients receiving mechanical ventilation (MV) after cardiac arrest. We performed a secondary analysis of three prospective, observational multicenter studies conducted in 1998, 2004 and 2010 in 927 ICUs from 40 countries. We screened 18,302 patients receiving MV for more than 12 hours during a one-month-period. We included 812 patients receiving MV after cardiac arrest. We collected data on demographics, daily ventilator settings, complications during ventilation and outcomes. Multivariate logistic regression analysis was performed to calculate odds ratios, determining which variables within 24 hours of hospital admission were associated with 28-day hospital mortality and occurrence of acute respiratory distress syndrome (ARDS) and pneumonia acquired during ICU stay at 48 hours after admission. Among 812 patients, 100 were included from 1998, 239 from 2004 and 473 from 2010. Ventilatory management changed over time, with decreased tidal volumes (VT) (1998: mean 8.9 (standard deviation (SD) 2) ml/kg actual body weight (ABW), 2010: 6.7 (SD 2) ml/kg ABW; 2004: 9 (SD 2.3) ml/kg predicted body weight (PBW), 2010: 7.95 (SD 1.7) ml/kg PBW) and increased positive end-expiratory pressure (PEEP) (1998: mean 3.5 (SD 3), 2010: 6.5 (SD 3); P <0.001). Patients included from 2010 had more sepsis, cardiovascular dysfunction and neurological failure, but 28-day hospital mortality was similar over time (52% in 1998, 57% in 2004 and 52% in 2010). Variables independently associated with 28-day hospital mortality were: older age, PaO2 <60 mmHg, cardiovascular dysfunction and less use of sedative agents. Higher VT, and plateau pressure with lower PEEP were associated with occurrence of ARDS and pneumonia acquired during ICU stay. Protective mechanical ventilation with lower VT and higher PEEP is more

  18. Volume-targeted ventilation and arterial carbon dioxide in neonates.

    Science.gov (United States)

    Dawson, Catherine; Davies, Mark William

    2005-01-01

    To review the arterial carbon dioxide tensions (PaCO(2)) in newborn infants ventilated using synchronized intermittent mandatory ventilation (SIMV) in volume guarantee mode (using the Dräger Babylog 8000+) with a unit policy targeting tidal volumes of approximately 4 mL/kg. Data on ventilator settings and arterial PaCO(2) levels were collected on all arterial blood gases (ABG; n = 288) from 50 neonates ( 65 mmHg) were determined. The mean (SD) PaCO(2) during the first 48 h was 46.6 (9.0) mmHg. The mean (SD) PaCO(2) on the first blood gas of those infants commenced on volume guarantee from admission was 45.1 (12.5) mmHg. Severe hypo- or hypercapnoea occurred in 8% of infants at the time of their first blood gas measurement, and in levels at the first blood gas measurement and during the first 48 h of life; and avoid severe hypo- or hypercapnoea over 90% of the time.

  19. Comparison of Active and Passive Humidifiers on Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    H. Dilek Mersin Özcanoğlu

    2010-12-01

    Full Text Available Objective: To research the effectiveness on humidifying, respiratory mechanics, bacterial colonization and infection rates of continuous usage for 96 hours of active and passive humidifiers which are used for heating and moisturizing the inspired gases in patients under mechanical ventilation. Materials and Methods: Adult patients who are expected to support at least 4 days under mechanical ventilation, excluding patients with primary lung disease and sepsis, are included in the research. Patients are separated in two groups as a passive humidifier group (heat moisture exchange filter (n=16 and an active humidifier group (n=14. In passive humidifier group, humidifier is used continuously for 96 hours without change. In active humidifier group moisturizing is obtained by using sterile distilled water in heated humidifier. Patients whose demographic characteristics were recorded and first 24 hour APACHE II scores were calculated, were taking chest X-Ray’s daily. Respiratory mechanics measurements were recorded twice a day which were watched in Servo300A ventilators respiratory mechanics monitor, in patients under volume controlled ventilation. The amount of moisture and liquidity of the secretion in endotracheal tube were recorded and scored visually. The endotracheal aspiration samples at the beginning and at the end of 96th hour and respiratory circuits ventilator side sample taken at 96th hour were studied microbiologically. Cultures and colonial counts were studied at Cerrahpasa Medical Faculty Microbiology Laboratory. Results: There were no significant difference in two groups by demographic data, APACHE II scores and illness diagnoses. In passive humidifier group, respiratory mechanics showed no significant difference between the beginning and the 4th day (p>0.05. In active humidifier group when MAP, PEEPtot, EEF, Rins, Rexp values showed no significant difference between the beginning and the 4th day but PIP values showed significant

  20. Effects of manual hyperinflation in preterm newborns under mechanical ventilation

    Science.gov (United States)

    Viana, Camila Chaves; Nicolau, Carla Marques; Juliani, Regina Celia Turola Passos; de Carvalho, Werther Brunow; Krebs, Vera Lucia Jornada

    2016-01-01

    Objective To assess the effects of manual hyperinflation, performed with a manual resuscitator with and without the positive end-expiratory pressure valve, on the respiratory function of preterm newborns under mechanical ventilation. Methods Cross-sectional study of hemodynamically stable preterm newborns with gestational age of less than 32 weeks, under mechanical ventilation and dependent on it at 28 days of life. Manual hyperinflation was applied randomly, alternating the use or not of the positive end-expiratory pressure valve, followed by tracheal aspiration for ending the maneuver. For nominal data, the two-tailed Wilcoxon test was applied at the 5% significance level and 80% power. Results Twenty-eight preterm newborns, with an average birth weight of 1,005.71 ± 372.16g, an average gestational age of 28.90 ± 1.79 weeks, an average corrected age of 33.26 ± 1.78 weeks, and an average mechanical ventilation time of 29.5 (15 - 53) days, were studied. Increases in inspiratory and expiratory volumes occurred between time-points A5 (before the maneuver) and C1 (immediately after tracheal aspiration) in both the maneuver with the valve (p = 0.001 and p = 0.009) and without the valve (p = 0.026 and p = 0.001), respectively. There was also an increase in expiratory resistance between time-points A5 and C1 (p = 0.044). Conclusion Lung volumes increased when performing the maneuver with and without the valve, with a significant difference in the first minute after aspiration. There was a significant difference in expiratory resistance between the time-points A5 (before the maneuver) and C1 (immediately after tracheal aspiration) in the first minute after aspiration within each maneuver. PMID:27737427

  1. Lung Injury After One-Lung Ventilation: A Review of the Pathophysiologic Mechanisms Affecting the Ventilated and the Collapsed Lung.

    Science.gov (United States)

    Lohser, Jens; Slinger, Peter

    2015-08-01

    Lung injury is the leading cause of death after thoracic surgery. Initially recognized after pneumonectomy, it has since been described after any period of 1-lung ventilation (OLV), even in the absence of lung resection. Overhydration and high tidal volumes were thought to be responsible at various points; however, it is now recognized that the pathophysiology is more complex and multifactorial. All causative mechanisms known to trigger ventilator-induced lung injury have been described in the OLV setting. The ventilated lung is exposed to high strain secondary to large, nonphysiologic tidal volumes and loss of the normal functional residual capacity. In addition, the ventilated lung experiences oxidative stress, as well as capillary shear stress because of hyperperfusion. Surgical manipulation and/or resection of the collapsed lung may induce lung injury. Re-expansion of the collapsed lung at the conclusion of OLV invariably induces duration-dependent, ischemia-reperfusion injury. Inflammatory cytokines are released in response to localized injury and may promote local and contralateral lung injury. Protective ventilation and volatile anesthesia lessen the degree of injury; however, increases in biochemical and histologic markers of lung injury appear unavoidable. The endothelial glycocalyx may represent a common pathway for lung injury creation during OLV, because it is damaged by most of the recognized lung injurious mechanisms. Experimental therapies to stabilize the endothelial glycocalyx may afford the ability to reduce lung injury in the future. In the interim, protective ventilation with tidal volumes of 4 to 5 mL/kg predicted body weight, positive end-expiratory pressure of 5 to 10 cm H2O, and routine lung recruitment should be used during OLV in an attempt to minimize harmful lung stress and strain. Additional strategies to reduce lung injury include routine volatile anesthesia and efforts to minimize OLV duration and hyperoxia.

  2. 小潮气量机械通气对全麻患儿术中肺功能的影响%Influence of small tidal volume mechanical ventilation to lung function of children in general anesthesia

    Institute of Scientific and Technical Information of China (English)

    李体忠; 刘亚玲; 罗炜; 马源

    2012-01-01

    Objective To study the effect of low tidal volume mechanical ventilation on the lung protection of children in intraoperative anesthesia. Methods 48 cases of children with intestinal obstruction laparotomy were selected and randomly divided into A and B groups. The two groups were treated with low tidal volume and high tidal volume mechanical ventilation separately. Their peripheral blood were collected before intubation, after intubation 1 h and at the end of surgery, using enzyme-linked immunosorbent assay (ELISA) to test patients' plasma interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentration and to analyze arterial blood gas at the same time. Results The two groups in plasma IL-6 levels in tracheal intubation had no significant difference before. In group A there was no significant difference in IL-6 levels. Group B's plasma levels of IL-6 1 h after intubation and at the end of surgery was significantly higher (P <0.05) compared with before intubation. Two groups' plasma levels of TNF-α before intubation had no significant difference and group B's levels were significantly higher (P <0.05) than those 1 h after intubation and at the end of surgery compared with before intubation. Conclusion Tidal volume ventilation can cause increase of plasma IL-6 and TNF-α level in children, which may be one of the reasons to result in mechanical ventilation-induced lung injury. The low tidal volume ventilation used for children in the maintenance of anesthesia in ventilation can contribute to the protection of lung function.%目的 探讨小潮气量机械通气对全麻患儿术中肺功能的影响.方法 选取48例行肠梗阻剖腹探查术的患儿,随机分为A、B两组,术中分别采用小潮气量和大潮气量机械通气,于插管前、插管后1h和手术结束时分别采集外周血,用酶联免疫法检测患儿血浆中白介素-6(IL-6)和肿瘤坏死因子-α (TNF-α)的浓度,同时抽取动脉血行血气分析.结果 A组其他时点

  3. Lung volume, breathing pattern and ventilation inhomogeneity in preterm and term infants.

    Directory of Open Access Journals (Sweden)

    Philipp Latzin

    Full Text Available BACKGROUND: Morphological changes in preterm infants with bronchopulmonary dysplasia (BPD have functional consequences on lung volume, ventilation inhomogeneity and respiratory mechanics. Although some studies have shown lower lung volumes and increased ventilation inhomogeneity in BPD infants, conflicting results exist possibly due to differences in sedation and measurement techniques. METHODOLOGY/PRINCIPAL FINDINGS: We studied 127 infants with BPD, 58 preterm infants without BPD and 239 healthy term-born infants, at a matched post-conceptional age of 44 weeks during quiet natural sleep according to ATS/ERS standards. Lung function parameters measured were functional residual capacity (FRC and ventilation inhomogeneity by multiple breath washout as well as tidal breathing parameters. Preterm infants with BPD had only marginally lower FRC (21.4 mL/kg than preterm infants without BPD (23.4 mL/kg and term-born infants (22.6 mL/kg, though there was no trend with disease severity. They also showed higher respiratory rates and lower ratios of time to peak expiratory flow and expiratory time (t(PTEF/t(E than healthy preterm and term controls. These changes were related to disease severity. No differences were found for ventilation inhomogeneity. CONCLUSIONS: Our results suggest that preterm infants with BPD have a high capacity to maintain functional lung volume during natural sleep. The alterations in breathing pattern with disease severity may reflect presence of adaptive mechanisms to cope with the disease process.

  4. No-sedation during mechanical ventilation

    DEFF Research Database (Denmark)

    Laerkner, Eva; Stroem, Thomas; Toft, Palle

    2016-01-01

    care unit (ICU), patients were Richmond Agitation and Sedation Scale (RASS) scored, nursing workload was measured with the Nursing Care Recording System (NCR11) and nurse's self-assessment of workload was reported on a Numeric Rating Scale from 1 (low) to 10 (high). RESULTS: Patients from the no......BACKGROUND: Evidence is growing that less or no-sedation is possible and beneficial for patients during mechanical ventilation. AIM: To investigate if there was a difference in patient consciousness and nursing workload comparing a group of patients receiving no-sedation with a group of sedated......-sedation group had a median RASS score of -0·029 compared with -2 in the sedated group (P nurses self-reported workload was the same in both groups (P = 0·085). Because...

  5. Heliox Improves Carbon Dioxide Removal during Lung Protective Mechanical Ventilation

    NARCIS (Netherlands)

    Beurskens, Charlotte J; Brevoord, Daniel; Lagrand, Wim K; van den Bergh, Walter M; Vroom, Margreeth B; Preckel, Benedikt; Horn, Janneke; Juffermans, Nicole P

    2014-01-01

    Introduction. Helium is a noble gas with low density and increased carbon dioxide (CO2) diffusion capacity. This allows lower driving pressures in mechanical ventilation and increased CO2 diffusion. We hypothesized that heliox facilitates ventilation in patients during lung-protective mechanical ven

  6. Prolonged mechanical ventilation induces cell cycle arrest in newborn rat lung.

    Directory of Open Access Journals (Sweden)

    Andreas A Kroon

    Full Text Available RATIONALE: The molecular mechanism(s by which mechanical ventilation disrupts alveolar development, a hallmark of bronchopulmonary dysplasia, is unknown. OBJECTIVE: To determine the effect of 24 h of mechanical ventilation on lung cell cycle regulators, cell proliferation and alveolar formation in newborn rats. METHODS: Seven-day old rats were ventilated with room air for 8, 12 and 24 h using relatively moderate tidal volumes (8.5 mL.kg⁻¹. MEASUREMENT AND MAIN RESULTS: Ventilation for 24 h (h decreased the number of elastin-positive secondary crests and increased the mean linear intercept, indicating arrest of alveolar development. Proliferation (assessed by BrdU incorporation was halved after 12 h of ventilation and completely arrested after 24 h. Cyclin D1 and E1 mRNA and protein levels were decreased after 8-24 h of ventilation, while that of p27(Kip1 was significantly increased. Mechanical ventilation for 24 h also increased levels of p57(Kip2, decreased that of p16(INK4a, while the levels of p21(Waf/Cip1 and p15(INK4b were unchanged. Increased p27(Kip1 expression coincided with reduced phosphorylation of p27(Kip1 at Thr¹⁵⁷, Thr¹⁸⁷ and Thr¹⁹⁸ (p<0.05, thereby promoting its nuclear localization. Similar -but more rapid- changes in cell cycle regulators were noted when 7-day rats were ventilated with high tidal volume (40 mL.kg⁻¹ and when fetal lung epithelial cells were subjected to a continuous (17% elongation cyclic stretch. CONCLUSION: This is the first demonstration that prolonged (24 h of mechanical ventilation causes cell cycle arrest in newborn rat lungs; the arrest occurs in G₁ and is caused by increased expression and nuclear localization of Cdk inhibitor proteins (p27(Kip1, p57(Kip2 from the Kip family.

  7. Comparison of Airway Pressure Release Ventilation to Conventional Mechanical Ventilation in the Early Management of Smoke Inhalation Injury in Swine

    Science.gov (United States)

    2011-01-01

    acute respiratory distress syndrome developed ( PaO2 /FIO2 ratio ), plateau pressures were limited to ន cm H2O. Six uninjured pigs received...conventional mechanical ventilation for 48 hrs and served as time controls. Changes in PaO2 /FIO2 ratio, tidal volume, respiratory rate, mean airway pressure...plateau pressure, and hemody- namic variables were recorded. Survival was assessed using Kaplan- Meier analysis. PaO2 /FIO2 ratio was lower in airway

  8. A taxonomy for mechanical ventilation: 10 fundamental maxims.

    Science.gov (United States)

    Chatburn, Robert L; El-Khatib, Mohamad; Mireles-Cabodevila, Eduardo

    2014-11-01

    The American Association for Respiratory Care has declared a benchmark for competency in mechanical ventilation that includes the ability to "apply to practice all ventilation modes currently available on all invasive and noninvasive mechanical ventilators." This level of competency presupposes the ability to identify, classify, compare, and contrast all modes of ventilation. Unfortunately, current educational paradigms do not supply the tools to achieve such goals. To fill this gap, we expand and refine a previously described taxonomy for classifying modes of ventilation and explain how it can be understood in terms of 10 fundamental constructs of ventilator technology: (1) defining a breath, (2) defining an assisted breath, (3) specifying the means of assisting breaths based on control variables specified by the equation of motion, (4) classifying breaths in terms of how inspiration is started and stopped, (5) identifying ventilator-initiated versus patient-initiated start and stop events, (6) defining spontaneous and mandatory breaths, (7) defining breath sequences (8), combining control variables and breath sequences into ventilatory patterns, (9) describing targeting schemes, and (10) constructing a formal taxonomy for modes of ventilation composed of control variable, breath sequence, and targeting schemes. Having established the theoretical basis of the taxonomy, we demonstrate a step-by-step procedure to classify any mode on any mechanical ventilator.

  9. Pulse pressure variation and prediction of fluid responsiveness in patients ventilated with low tidal volumes

    Directory of Open Access Journals (Sweden)

    Clarice Daniele Alves de Oliveira-Costa

    2012-07-01

    Full Text Available OBJECTIVE: To determine the utility of pulse pressure variation (ΔRESP PP in predicting fluid responsiveness in patients ventilated with low tidal volumes (V T and to investigate whether a lower ΔRESP PP cut-off value should be used when patients are ventilated with low tidal volumes. METHOD: This cross-sectional observational study included 37 critically ill patients with acute circulatory failure who required fluid challenge. The patients were sedated and mechanically ventilated with a V T of 6-7 ml/kg ideal body weight, which was monitored with a pulmonary artery catheter and an arterial line. The mechanical ventilation and hemodynamic parameters, including ΔRESP PP, were measured before and after fluid challenge with 1,000 ml crystalloids or 500 ml colloids. Fluid responsiveness was defined as an increase in the cardiac index of at least 15%. ClinicalTrial.gov: NCT01569308. RESULTS: A total of 17 patients were classified as responders. Analysis of the area under the ROC curve (AUC showed that the optimal cut-off point for ΔRESP PP to predict fluid responsiveness was 10% (AUC = 0.74. Adjustment of the ΔRESP PP to account for driving pressure did not improve the accuracy (AUC = 0.76. A ΔRESP PP>10% was a better predictor of fluid responsiveness than central venous pressure (AUC = 0.57 or pulmonary wedge pressure (AUC = 051. Of the 37 patients, 25 were in septic shock. The AUC for ΔRESP PP>10% to predict responsiveness in patients with septic shock was 0.484 (sensitivity, 78%; specificity, 93%. CONCLUSION: The parameter D RESP PP has limited value in predicting fluid responsiveness in patients who are ventilated with low tidal volumes, but a ΔRESP PP>10% is a significant improvement over static parameters. A ΔRESP PP > 10% may be particularly useful for identifying responders in patients with septic shock.

  10. Titin and diaphragm dysfunction in mechanically ventilated rats.

    NARCIS (Netherlands)

    Hees, H.W.H. van; Schellekens, W.J.M.; Andrade Acuna, G.L.; Linkels, M.; Hafmans, T.G.M.; Ottenheijm, C.A.C.; Granzier, H.L.; Scheffer, G.J.; Hoeven, J.G. van der; Dekhuijzen, P.N.R.; Heunks, L.M.A.

    2012-01-01

    PURPOSE: Diaphragm weakness induced by mechanical ventilation may contribute to difficult weaning from the ventilator. For optimal force generation the muscle proteins myosin and titin are indispensable. The present study investigated if myosin and titin loss or dysfunction are involved in mechanica

  11. Amyotrophic Lateral Sclerosis Patients' Perspectives on Use of Mechanical Ventilation.

    Science.gov (United States)

    Young, Jenny M.; And Others

    1994-01-01

    Interviewed 13 amyotrophic lateral sclerosis patients. All believed that they alone should make decision regarding use of mechanical ventilation. Factors they considered important were quality of life, severity of disability, availability of ventilation by means of nasal mask, possible admission to long-term care facility, ability to discontinue…

  12. Mechanical ventilation drives inflammation in severe viral bronchiolitis.

    Directory of Open Access Journals (Sweden)

    Marije P Hennus

    Full Text Available INTRODUCTION: Respiratory insufficiency due to severe respiratory syncytial virus (RSV infection is the most frequent cause of paediatric intensive care unit admission in infants during the winter season. Previous studies have shown increased levels of inflammatory mediators in airways of mechanically ventilated children compared to spontaneous breathing children with viral bronchiolitis. In this prospective observational multi-center study we aimed to investigate whether this increase was related to disease severity or caused by mechanical ventilation. MATERIALS AND METHODS: Nasopharyngeal aspirates were collected <1 hour before intubation and 24 hours later in RSV bronchiolitis patients with respiratory failure (n = 18 and non-ventilated RSV bronchiolitis controls (n = 18. Concentrations of the following cytokines were measured: interleukin (IL-1α, IL-1β, IL-6, monocyte chemotactic protein (MCP-1 and macrophage inflammatory protein (MIP-1α. RESULTS: Baseline cytokine levels were comparable between ventilated and non-ventilated infants. After 24 hours of mechanical ventilation mean cytokine levels, except for MIP-1α, were elevated compared to non-ventilated infected controls: IL-1α (159 versus 4 pg/ml, p<0.01, IL-1β (1068 versus 99 pg/ml, p<0.01, IL-6 (2343 versus 958 pg/ml, p<0.05 and MCP-1 (174 versus 26 pg/ml, p<0.05. CONCLUSIONS: Using pre- and post-intubation observations, this study suggests that endotracheal intubation and subsequent mechanical ventilation cause a robust pulmonary inflammation in infants with RSV bronchiolitis.

  13. Delirium during Weaning from Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    Marcela Aparecida Leite

    2014-01-01

    Full Text Available Background. We compare the incidence of delirium before and after extubation and identify the risk factors and possible predictors for the occurrence of delirium in this group of patients. Methods. Patients weaned from mechanical ventilation (MV and extubated were included. The assessment of delirium was conducted using the confusion assessment method for the ICU and completed twice per day until discharge from the intensive care unit. Results. Sixty-four patients were included in the study, 53.1% of whom presented with delirium. The risk factors of delirium were age (P=0.01, SOFA score (P=0.03, APACHE score (P=0.01, and a neurological cause of admission (P=0.01. The majority of the patients began with delirium before or on the day of extubation. Hypoactive delirium was the most common form. Conclusion. Acute (traumatic or medical neurological injuries were important risk factors in the development of delirium. During the weaning process, delirium developed predominantly before or on the same day of extubation and was generally hypoactive (more difficult to detect. Therefore, while planning early prevention strategies, attention must be focused on neurological patients who are receiving MV and possibly even on patients who are still under sedation.

  14. Effect of high tidal volume ventilation and lipopolysaccharide on mitogen-activated protein kinase in rat lung tissue

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Mechanical ventilation, a crucial therapy to acute respiratory distress syndrome (ARDS), could exacerbate lung injury, and even result in ventilator-induced lung injury (VILI) if misused in some condition1. Over-activating inflammatory cells and expanding inflammatory responses, which are induced by infection, are fundamental reasons for ARDS. Among them, mitogen-activated protein kinase (MAPK) intracellular signal transduction pathways are key processes. This study aimed to investigate the time course of MAPK activation in rat lung tissue after high tidal volume (VT) ventilation and the role of lipopolysaccharide (LPS) in high-sensitivity, and to elucidate the effect of the pathway on VILI.

  15. Hyperpolarized 3He magnetic resonance imaging ventilation defects in asthma: relationship to airway mechanics.

    Science.gov (United States)

    Leary, Del; Svenningsen, Sarah; Guo, Fumin; Bhatawadekar, Swati; Parraga, Grace; Maksym, Geoffrey N

    2016-04-01

    In patients with asthma, magnetic resonance imaging (MRI) provides direct measurements of regional ventilation heterogeneity, the etiology of which is not well-understood, nor is the relationship of ventilation abnormalities with lung mechanics. In addition, respiratory resistance and reactance are often abnormal in asthmatics and the frequency dependence of respiratory resistance is thought to reflect ventilation heterogeneity. We acquiredMRIventilation defect maps, forced expiratory volume in one-second (FEV1), and airways resistance (Raw) measurements, and used a computational airway model to explore the relationship of ventilation defect percent (VDP) with simulated measurements of respiratory system resistance (Rrs) and reactance (Xrs).MRIventilation defect maps were experimentally acquired in 25 asthmatics before, during, and after methacholine challenge and these were nonrigidly coregistered to the airway tree model. Using the model coregistered to ventilation defect maps, we narrowed proximal (9th) and distal (14th) generation airways that were spatially related to theMRIventilation defects. The relationships forVDPwith Raw measured using plethysmography (r = 0.79), and model predictions of Rrs>14(r = 0.91,P 9(r = 0.88,P mechanics measurements were different (P mechanics and ventilation defects, impedance predictions were made using a computational airway tree model with simulated constriction of airways related to ventilation defects measured in mild-moderate asthmatics.

  16. Mechanical ventilation with heat recovery in cold climates

    DEFF Research Database (Denmark)

    Kragh, Jesper; Rose, Jørgen; Svendsen, Svend

    2005-01-01

    Building ventilation is necessary to achieve a healthy and comfortable indoor environment, but as energy prices continue to rise it is necessary to reduce the energy consumption. Using mechanical ventilation with heat recovery reduces the ventilation heat loss significantly, but in cold climates...... freezes to ice. The analysis of measurements from existing ventilation systems with heat recovery used in single-family houses in Denmark and a test of a standard heat recovery unit in the laboratory have clearly shown that this problem occurs when the outdoor temperature gets below approximately –5º......C. Due to the ice problem mechanical ventilation systems with heat recovery are often installed with an extra preheating system reducing the energy saving potential significantly. New designs of high efficient heat recovery units capable of continuously defrosting the ice without using extra energy...

  17. Mechanical ventilation and house-dust mites. Mekanisk ventilation og husstoevmider

    Energy Technology Data Exchange (ETDEWEB)

    Korsgaard, J. (Lungeklinikken, Aarhus Kommunehospital, Aarhus (DK))

    1991-01-01

    Nationally and internationally, it is recognised that the rational way to reduce inhabitant exposure to house-dust meters in a temperate climate is to reduce indoor absolute humidity to a level below 7.0 g/kg in the dry winter period. Consequently, it is medically recommended to install mechanical ventilation as environmental treatment of patients with chronic asthma caused by indoor exposure to house-dust mites. In this controlled investigation on the effect of mechanical ventilation on indoor climate conditions, it is documented that the establishment of a basic ventilation rate of 0.5 ach implies a significant reduction in the occurrence of house-dust mites in dwellings. Parallel with this effect, the rate of inside condensation on double-glazed windows was reduced, and the reported complaint rate of humid air, stuffy and dustry air and the indoor smelling sensation were reduced by a factor 2 to 7. No side effects relating to ventilation equipment were reported. It is conclued that the installation of mechanical ventilation in the treatment of mite allergy should be individualized with recommended air exchange rates adjusted to the actual size of dwelling and number of inhabitants. Furthermore care should be taken to avoid risk of condensation in the ventilation equipment. (author).

  18. Linking Ventilation Heterogeneity Quantified via Hyperpolarized 3He MRI to Dynamic Lung Mechanics and Airway Hyperresponsiveness.

    Science.gov (United States)

    Lui, Justin K; Parameswaran, Harikrishnan; Albert, Mitchell S; Lutchen, Kenneth R

    2015-01-01

    Advancements in hyperpolarized helium-3 MRI (HP 3He-MRI) have introduced the ability to render and quantify ventilation patterns throughout the anatomic regions of the lung. The goal of this study was to establish how ventilation heterogeneity relates to the dynamic changes in mechanical lung function and airway hyperresponsiveness in asthmatic subjects. In four healthy and nine mild-to-moderate asthmatic subjects, we measured dynamic lung resistance and lung elastance from 0.1 to 8 Hz via a broadband ventilation waveform technique. We quantified ventilation heterogeneity using a recently developed coefficient of variation method from HP 3He-MRI imaging. Dynamic lung mechanics and imaging were performed at baseline, post-challenge, and after a series of five deep inspirations. AHR was measured via the concentration of agonist that elicits a 20% decrease in the subject's forced expiratory volume in one second compared to baseline (PC20) dose. The ventilation coefficient of variation was correlated to low-frequency lung resistance (R = 0.647, P ventilation heterogeneity. Also, the degree of AHR appears to be dependent on the degree to which baseline airway constriction creates baseline ventilation heterogeneity. HP 3He-MRI imaging may be a powerful predictor of the degree of AHR and in tracking the efficacy of therapy.

  19. Assessment of respiratory output in mechanically ventilated patients.

    Science.gov (United States)

    Laghi, Franco

    2005-06-01

    Mechanically ventilated patients are subject to few pathophysiologic disturbances that have such intuitive importance as abnormal function of the respiratory output. Abnormal function of the respiratory output plays a fundamental role in all aspects of mechanical ventilation: in determining which patients require mechanical ventilation, in determining the interaction between a patient and the ventilator, and in determining when a patient can tolerate discontinuation of mechanical ventilation. Monitoring indexes such as the rate of rise in electrical activity of the diaphragm, Po.1, (dP/dt)max, and Pmus, has provided insight into the performance of the respiratory centers in critically ill patients, but these methods require considerable refinement. A large body of research on measurements of energy expenditure of the respiratory muscles, such as pressure-time product, and measurements of inspiratory effort, such as the tension-time index, is currently accumulating. Several challenges, however, lay ahead regarding these indices. First, there is the need to identify the correct level of pressure generation and respiratory muscle effort that should be attained in the day-to-day management of mechanically ventilated patients. The correct titration of ventilator setting should not cause iatrogenic muscle damage because the support is excessive or insufficient. One of the challenges in reaching this goal is that for the same patient, different underlying pathologic conditions (eg, sepsis or ventilator-associated muscle injury) may require different levels of support. Second, many of the measurements of pressure generation and effort have been confined to the research laboratory. Modifications of the technology to achieve accurate measurements in the intensive care unit-outside of the research laboratory--are needed. To facilitate individual titration of ventilator settings, the new technologies must provide easier access to quantification of drive, pressure output, and

  20. Development of energy-efficient comfortable ventilation systems with air quality guided volume flow control and continuous monitoring of the window opening status. Part 1. Use of the LuQaS triple sensor for air quality guided volume flow control of mechanical ventilation systems in domestic buildings. Research project; Entwicklung energieeffizienter Komfortlueftungsanlagen mit luftqualitaetsgefuehrter Volumenstromregelung und kontinuierlicher Erfassung des Fensteroeffnungszustandes. Teilbericht 1. Einsatz des LuQaS-Triple-Sensors zur luftqualitaetsgefuehrten Volumenstromregelung von mechanischen Lueftungsanlagen in Wohngebaeuden. Forschungsprojekt

    Energy Technology Data Exchange (ETDEWEB)

    Grossklos, Marc; Ebel, Witta; Knissel, Jens

    2011-05-15

    The report presents the preparatory work on the research project of the above title. The first chapter presents a status report on air quality monitoring inside rooms and evaluates the projects so far in which the LuQaS air quality sensor was used. The second chapter is a documentation of preliminary measurements using the LuQaS sensor in two passive residential buildings and several individual measurements for sensor calibration. It was found that in apartments with mechanical ventilation, the sensor reflects the user activities; further, the measured values indicate signal changes also in the off-air of the building, so that control via central sensors in the ventilation and off-air systems appears feasible. The third chapter discusses control strategies for air quality control. Apart from a discussion of control unit types, operating regimes, methods to determine rated values, and additional control functions, the effects of threshold value control with different threshold limit values and volume flow changes on the air quality of a model building was simulated. The results prove the expectation that the air quality inside a building will be influenced positively by air quality control. Theoretical investigations of the DrD method will be presented in another part-report of the project.

  1. Mechanical ventilation with heat recovery in cold climates

    DEFF Research Database (Denmark)

    Kragh, Jesper; Rose, Jørgen; Svendsen, Svend

    2005-01-01

    like the Northern Europe or in arctic climate like in Greenland or Alaska these ventilation systems will typically face problems with ice formation in the heat exchanger. When the warm humid room air comes in contact with the cold surfaces inside the exchanger (cooled by the outside air), the moisture......Building ventilation is necessary to achieve a healthy and comfortable indoor environment, but as energy prices continue to rise it is necessary to reduce the energy consumption. Using mechanical ventilation with heat recovery reduces the ventilation heat loss significantly, but in cold climates...... freezes to ice. The analysis of measurements from existing ventilation systems with heat recovery used in single-family houses in Denmark and a test of a standard heat recovery unit in the laboratory have clearly shown that this problem occurs when the outdoor temperature gets below approximately –5º...

  2. Assessment of factors that influence weaning from long-term mechanical ventilation after cardiac surgery

    Directory of Open Access Journals (Sweden)

    Emília Nozawa

    2003-03-01

    Full Text Available OBJECTIVE: To analyze parameters of respiratory system mechanics and oxygenation and cardiovascular alterations involved in weaning tracheostomized patients from long-term mechanical ventilation after cardiac surgery. METHODS: We studied 45 patients in their postoperative period of cardiac surgery, who required long-term mechanical ventilation for more than 10 days and had to undergo tracheostomy due to unsuccessful weaning from mechanical ventilation. The parameters of respiratory system mechanics, oxigenation and the following factors were analyzed: type of surgical procedure, presence of cardiac dysfunction, time of extracorporeal circulation, and presence of neurologic lesions. RESULTS: Of the 45 patients studied, successful weaning from mechanical ventilation was achieved in 22 patients, while the procedure was unsuccessful in 23 patients. No statistically significant difference was observed between the groups in regard to static pulmonary compliance (p=0.23, airway resistance (p=0.21, and the dead space/tidal volume ratio (p=0.54. No difference was also observed in regard to the variables PaO2/FiO2 ratio (p=0.86, rapid and superficial respiration index (p=0.48, and carbon dioxide arterial pressure (p=0.86. Cardiac dysfunction and time of extracorporeal circulation showed a significant difference. CONCLUSION: Data on respiratory system mechanics and oxygenation were not parameters for assessing the success or failure. Cardiac dysfunction and time of cardiopulmonary bypass, however, significantly interfered with the success in weaning patients from mechanical ventilation.

  3. Evaluation of self-perception of mechanical ventilation knowledge among Brazilian final-year medical students, residents and emergency physicians

    Science.gov (United States)

    Tallo, Fernando Sabia; de Campos Vieira Abib, Simone; de Andrade Negri, Alexandre Jorgi; Filho, Paulo Cesar; Lopes, Renato Delascio; Lopes, Antônio Carlos

    2017-01-01

    OBJECTIVE: To present self-assessments of knowledge about mechanical ventilation made by final-year medical students, residents, and physicians taking qualifying courses at the Brazilian Society of Internal Medicine who work in urgent and emergency settings. METHODS: A 34-item questionnaire comprising different areas of knowledge and training in mechanical ventilation was given to 806 medical students, residents, and participants in qualifying courses at 11 medical schools in Brazil. The questionnaire’s self-assessment items for knowledge were transformed into scores. RESULTS: The average score among all participants was 21% (0-100%). Of the total, 85% respondents felt they did not receive sufficient information about mechanical ventilation during medical training. Additionally, 77% of the group reported that they would not know when to start noninvasive ventilation in a patient, and 81%, 81%, and 89% would not know how to start volume control, pressure control and pressure support ventilation modes, respectively. Furthermore, 86.4% and 94% of the participants believed they would not identify the basic principles of mechanical ventilation in patients with obstructive pulmonary disease and acute respiratory distress syndrome, respectively, and would feel insecure beginning ventilation. Finally, 77% said they would fear for the safety of a patient requiring invasive mechanical ventilation under their care. CONCLUSION: Self-assessment of knowledge and self-perception of safety for managing mechanical ventilation were deficient among residents, students and emergency physicians from a sample in Brazil.

  4. Numerical investigation of pulmonary drug delivery under mechanical ventilation conditions

    Science.gov (United States)

    Banerjee, Arindam; van Rhein, Timothy

    2012-11-01

    The effects of mechanical ventilation waveform on fluid flow and particle deposition were studied in a computer model of the human airways. The frequency with which aerosolized drugs are delivered to mechanically ventilated patients demonstrates the importance of understanding the effects of ventilation parameters. This study focuses specifically on the effects of mechanical ventilation waveforms using a computer model of the airways of patient undergoing mechanical ventilation treatment from the endotracheal tube to generation G7. Waveforms were modeled as those commonly used by commercial mechanical ventilators. Turbulence was modeled with LES. User defined particle force models were used to model the drag force with the Cunningham correction factor, the Saffman lift force, and Brownian motion force. The endotracheal tube (ETT) was found to be an important geometric feature, causing a fluid jet towards the right main bronchus, increased turbulence, and a recirculation zone in the right main bronchus. In addition to the enhanced deposition seen at the carinas of the airway bifurcations, enhanced deposition was also seen in the right main bronchus due to impaction and turbulent dispersion resulting from the fluid structures created by the ETT. Authors acknowledge financial support through University of Missouri Research Board Award.

  5. Sustained inflation at birth did not alter lung injury from mechanical ventilation in surfactant-treated fetal lambs.

    Directory of Open Access Journals (Sweden)

    Noah H Hillman

    Full Text Available BACKGROUND: Sustained inflations (SI are used with the initiation of ventilation at birth to rapidly recruit functional residual capacity and may decrease lung injury and the need for mechanical ventilation in preterm infants. However, a 20 second SI in surfactant-deficient preterm lambs caused an acute phase injury response without decreasing lung injury from subsequent mechanical ventilation. HYPOTHESIS: A 20 second SI at birth will decrease lung injury from mechanical ventilation in surfactant-treated preterm fetal lambs. METHODS: The head and chest of fetal sheep at 126±1 day GA were exteriorized, with tracheostomy and removal of fetal lung fluid prior to treatment with surfactant (300 mg in 15 ml saline. Fetal lambs were randomized to one of four 15 minute interventions: 1 PEEP 8 cmH2O; 2 20 sec SI at 40 cmH2O, then PEEP 8 cmH2O; 3 mechanical ventilation with 7 ml/kg tidal volume; or 4 20 sec SI then mechanical ventilation at 7 ml/kg. Fetal lambs remained on placental support for the intervention and for 30 min after the intervention. RESULTS: SI recruited a mean volume of 6.8±0.8 mL/kg. SI did not alter respiratory physiology during mechanical ventilation. Heat shock protein (HSP 70, HSP60, and total protein in lung fluid similarly increased in both ventilation groups. Modest pro-inflammatory cytokine and acute phase responses, with or without SI, were similar with ventilation. SI alone did not increase markers of injury. CONCLUSION: In surfactant treated fetal lambs, a 20 sec SI did not alter ventilation physiology or markers of lung injury from mechanical ventilation.

  6. An experimental study on the impacts of inspiratory and expiratory muscles activities during mechanical ventilation in ARDS animal model

    Science.gov (United States)

    Zhang, Xianming; Du, Juan; Wu, Weiliang; Zhu, Yongcheng; Jiang, Ying; Chen, Rongchang

    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 were measured during mechanical ventilation, and lung injury was determined histologically. As a result, for the comparable ventilator setting, preserved inspiratory muscles activity groups resulted in higher end-expiratory lung volume (EELV) and oxygenation index. In addition, less lung damage scores and lower levels of system inflammatory cytokines were revealed after 8 h of ventilation. In comparison, preserved expiratory muscles activity groups resulted in lower EELV and oxygenation index. Moreover, higher lung injury scores and inflammatory cytokines levels were observed after 8 h of ventilation. Our findings suggest that the activity of inspiratory muscles has beneficial effects, whereas that of expiratory muscles exerts adverse effects during mechanical ventilation in ARDS animal model. Therefore, for mechanically ventilated patients with ARDS, the demands for deep sedation or paralysis might be replaced by the strategy of expiratory muscles paralysis through epidural anesthesia. PMID:28230150

  7. Experimental analysis of fuzzy controlled energy efficient demand controlled ventilation economizer cycle variable air volume air conditioning system

    Directory of Open Access Journals (Sweden)

    Rajagopalan Parameshwaran

    2008-01-01

    Full Text Available In the quest for energy conservative building design, there is now a great opportunity for a flexible and sophisticated air conditioning system capable of addressing better thermal comfort, indoor air quality, and energy efficiency, that are strongly desired. The variable refrigerant volume air conditioning system provides considerable energy savings, cost effectiveness and reduced space requirements. Applications of intelligent control like fuzzy logic controller, especially adapted to variable air volume air conditioning systems, have drawn more interest in recent years than classical control systems. An experimental analysis was performed to investigate the inherent operational characteristics of the combined variable refrigerant volume and variable air volume air conditioning systems under fixed ventilation, demand controlled ventilation, and combined demand controlled ventilation and economizer cycle techniques for two seasonal conditions. The test results of the variable refrigerant volume and variable air volume air conditioning system for each techniques are presented. The test results infer that the system controlled by fuzzy logic methodology and operated under the CO2 based mechanical ventilation scheme, effectively yields 37% and 56% per day of average energy-saving in summer and winter conditions, respectively. Based on the experimental results, the fuzzy based combined system can be considered to be an alternative energy efficient air conditioning scheme, having significant energy-saving potential compared to the conventional constant air volume air conditioning system.

  8. Frequency dependence of lung volume changes during superimposed high-frequency jet ventilation and high-frequency jet ventilation.

    Science.gov (United States)

    Sütterlin, R; Priori, R; Larsson, A; LoMauro, A; Frykholm, P; Aliverti, A

    2014-01-01

    Superimposed high-frequency jet ventilation (SHFJV) has proved to be safe and effective in clinical practice. However, it is unclear which frequency range optimizes ventilation and gas exchange. The aim of this study was to systematically compare high-frequency jet ventilation (HFJV) with HFJV by assessing chest wall volume variations (ΔEEV(CW)) and gas exchange in relation to variable high frequency. SHFJV or HFJV were used alternatively to ventilate the lungs of 10 anaesthetized pigs (21-25 kg). The low-frequency component was kept at 16 min(-1) in SHFJV. In both modes, high frequencies ranging from 100 to 1000 min(-1) were applied in random order and ventilation was maintained for 5 min in all modalities. Chest wall volume variations were obtained using opto-electronic plethysmography. Airway pressures and arterial blood gases were measured repeatedly. SHFJV increased ΔEEV(CW) compared with HFJV; the difference ranged from 43 to 68 ml. Tidal volume (V(T)) was always >240 ml during SHFJV whereas during HFJV ranged from 92 ml at the ventilation frequency of 100 min(-1) to negligible values at frequencies >300 min(-1). We observed similar patterns for Pa(O₂) and Pa(CO₂). SHFJV provided generally higher, frequency-independent oxygenation (Pa(O₂) at least 32.0 kPa) and CO₂ removal (Pa(CO₂) ∼5.5 kPa), whereas HFJV led to hypoxia and hypercarbia at higher rates (Pa(O₂) 10 kPa at f(HF)>300 min(-1)). In a porcine model, SHFJV was more effective in increasing end-expiratory volume than single-frequency HFJV, but both modes may provide adequate ventilation in the absence of airway obstruction and respiratory disease, except for HFJV at frequencies ≥300 min(-1).

  9. CT-measured regional specific volume change reflects regional ventilation in supine sheep.

    Science.gov (United States)

    Fuld, Matthew K; Easley, R Blaine; Saba, Osama I; Chon, Deokiee; Reinhardt, Joseph M; Hoffman, Eric A; Simon, Brett A

    2008-04-01

    Computer tomography (CT) imaging techniques permit the noninvasive measurement of regional lung function. Regional specific volume change (sVol), determined from the change in lung density over a tidal breath, should correlate with regional ventilation and regional lung expansion measured with other techniques. sVol was validated against xenon (Xe)-CT-specific ventilation (sV) in four anesthetized, intubated, mechanically ventilated sheep. Xe-CT used expiratory gated axial scanning during the washin and washout of 55% Xe. sVol was measured from the tidal changes in tissue density (H, houndsfield units) of lung regions using the relationship sVol = [1,000(Hi - He)]/[He(1,000 + Hi)], where He and Hi are expiratory and inspiratory regional density. Distinct anatomical markings were used to define corresponding lung regions of interest between inspiratory, expiratory, and Xe-CT images, with an average region of interest size of 1.6 +/- 0.7 ml. In addition, sVol was compared with regional volume changes measured directly from the positions of implanted metal markers in an additional animal. A linear relationship between sVol and sV was demonstrated over a wide range of regional sV found in the normal supine lung, with an overall correlation coefficient (R(2)) of 0.66. There was a tight correlation (R(2) = 0.97) between marker-measured volume changes and sVol. Regional sVol, which involves significantly reduced exposure to radiation and Xe gas compared with the Xe-CT method, represents a safe and efficient surrogate for measuring regional ventilation in experimental studies and patients.

  10. The Effects of Guided Imagery on Patients Being Weaned from Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    LeeAnna Spiva

    2015-01-01

    Full Text Available The study purpose was to assess the effects of guided imagery on sedation levels, sedative and analgesic volume consumption, and physiological responses of patients being weaned from mechanical ventilation. Forty-two patients were selected from two community acute care hospitals. One hospital served as the comparison group and provided routine care (no intervention while the other hospital provided the guided imagery intervention. The intervention included two sessions, each lasting 60 minutes, offered during morning weaning trials from mechanical ventilation. Measurements were recorded in groups at baseline and 30- and 60-minute intervals and included vital signs and Richmond Agitation-Sedation Scale (RASS score. Sedative and analgesic medication volume consumption were recorded 24 hours prior to and after the intervention. The guided imagery group had significantly improved RASS scores and reduced sedative and analgesic volume consumption. During the second session, oxygen saturation levels significantly improved compared to the comparison group. Guided imagery group had 4.88 less days requiring mechanical ventilation and 1.4 reduction in hospital length of stay compared to the comparison group. Guided imagery may be complementary and alternative medicine (CAM intervention to provide during mechanical ventilation weaning trials.

  11. Cardiac output estimation using pulmonary mechanics in mechanically ventilated patients

    Directory of Open Access Journals (Sweden)

    Hann Christopher E

    2010-11-01

    Full Text Available Abstract The application of positive end expiratory pressure (PEEP in mechanically ventilated (MV patients with acute respiratory distress syndrome (ARDS decreases cardiac output (CO. Accurate measurement of CO is highly invasive and is not ideal for all MV critically ill patients. However, the link between the PEEP used in MV, and CO provides an opportunity to assess CO via MV therapy and other existing measurements, creating a CO measure without further invasiveness. This paper examines combining models of diffusion resistance and lung mechanics, to help predict CO changes due to PEEP. The CO estimator uses an initial measurement of pulmonary shunt, and estimations of shunt changes due to PEEP to predict CO at different levels of PEEP. Inputs to the cardiac model are the PV loops from the ventilator, as well as the oxygen saturation values using known respiratory inspired oxygen content. The outputs are estimates of pulmonary shunt and CO changes due to changes in applied PEEP. Data from two published studies are used to assess and initially validate this model. The model shows the effect on oxygenation due to decreased CO and decreased shunt, resulting from increased PEEP. It concludes that there is a trade off on oxygenation parameters. More clinically importantly, the model also examines how the rate of CO drop with increased PEEP can be used as a method to determine optimal PEEP, which may be used to optimise MV therapy with respect to the gas exchange achieved, as well as accounting for the impact on the cardiovascular system and its management.

  12. A new system for continuous and remote monitoring of patients receiving home mechanical ventilation

    Science.gov (United States)

    Battista, L.

    2016-09-01

    Home mechanical ventilation is the treatment of patients with respiratory failure or insufficiency by means of a mechanical ventilator at a patient's home. In order to allow remote patient monitoring, several tele-monitoring systems have been introduced in the last few years. However, most of them usually do not allow real-time services, as they have their own proprietary communication protocol implemented and some ventilation parameters are not always measured. Moreover, they monitor only some breaths during the whole day, despite the fact that a patient's respiratory state may change continuously during the day. In order to reduce the above drawbacks, this work reports the development of a novel remote monitoring system for long-term, home-based ventilation therapy; the proposed system allows for continuous monitoring of the main physical quantities involved during home-care ventilation (e.g., differential pressure, volume, and air flow rate) and is developed in order to allow observations of different remote therapy units located in different places of a city, region, or country. The developed remote patient monitoring system is able to detect various clinical events (e.g., events of tube disconnection and sleep apnea events) and has been successfully tested by means of experimental tests carried out with pulmonary ventilators typically used to support sick patients.

  13. Hypercapnia attenuates ventilator-induced diaphragm atrophy and modulates dysfunction

    NARCIS (Netherlands)

    Schellekens, W.J.M.; Hees, H.W.H. van; Kox, M.; Linkels, M.; Acuna, G.L.; Dekhuijzen, P.N.R.; Scheffer, G.J.; Hoeven, J.G. van der; Heunks, L.M.A.

    2014-01-01

    INTRODUCTION: Diaphragm weakness induced by prolonged mechanical ventilation may contribute to difficult weaning from the ventilator. Hypercapnia is an accepted side effect of low tidal volume mechanical ventilation, but the effects of hypercapnia on respiratory muscle function are largely unknown.

  14. Trend of maximal inspiratory pressure in mechanically ventilated patients: predictors

    Directory of Open Access Journals (Sweden)

    Pedro Caruso

    2008-01-01

    Full Text Available INTRODUCTION: It is known that mechanical ventilation and many of its features may affect the evolution of inspiratory muscle strength during ventilation. However, this evolution has not been described, nor have its predictors been studied. In addition, a probable parallel between inspiratory and limb muscle strength evolution has not been investigated. OBJECTIVE: To describe the variation over time of maximal inspiratory pressure during mechanical ventilation and its predictors. We also studied the possible relationship between the evolution of maximal inspiratory pressure and limb muscle strength. METHODS: A prospective observational study was performed in consecutive patients submitted to mechanical ventilation for > 72 hours. The maximal inspiratory pressure trend was evaluated by the linear regression of the daily maximal inspiratory pressure and a logistic regression analysis was used to look for independent maximal inspiratory pressure trend predictors. Limb muscle strength was evaluated using the Medical Research Council score. RESULTS: One hundred and sixteen patients were studied, forty-four of whom (37.9% presented a decrease in maximal inspiratory pressure over time. The members of the group in which maximal inspiratory pressure decreased underwent deeper sedation, spent less time in pressure support ventilation and were extubated less frequently. The only independent predictor of the maximal inspiratory pressure trend was the level of sedation (OR=1.55, 95% CI 1.003 - 2.408; p = 0.049. There was no relationship between the maximal inspiratory pressure trend and limb muscle strength. CONCLUSIONS: Around forty percent of the mechanically ventilated patients had a decreased maximal inspiratory pressure during mechanical ventilation, which was independently associated with deeper levels of sedation. There was no relationship between the evolution of maximal inspiratory pressure and the muscular strength of the limb.

  15. Humidification during mechanical ventilation in the adult patient.

    Science.gov (United States)

    Al Ashry, Haitham S; Modrykamien, Ariel M

    2014-01-01

    Humidification of inhaled gases has been standard of care in mechanical ventilation for a long period of time. More than a century ago, a variety of reports described important airway damage by applying dry gases during artificial ventilation. Consequently, respiratory care providers have been utilizing external humidifiers to compensate for the lack of natural humidification mechanisms when the upper airway is bypassed. Particularly, active and passive humidification devices have rapidly evolved. Sophisticated systems composed of reservoirs, wires, heating devices, and other elements have become part of our usual armamentarium in the intensive care unit. Therefore, basic knowledge of the mechanisms of action of each of these devices, as well as their advantages and disadvantages, becomes a necessity for the respiratory care and intensive care practitioner. In this paper, we review current methods of airway humidification during invasive mechanical ventilation of adult patients. We describe a variety of devices and describe the eventual applications according to specific clinical conditions.

  16. Humidification during Mechanical Ventilation in the Adult Patient

    Directory of Open Access Journals (Sweden)

    Haitham S. Al Ashry

    2014-01-01

    Full Text Available Humidification of inhaled gases has been standard of care in mechanical ventilation for a long period of time. More than a century ago, a variety of reports described important airway damage by applying dry gases during artificial ventilation. Consequently, respiratory care providers have been utilizing external humidifiers to compensate for the lack of natural humidification mechanisms when the upper airway is bypassed. Particularly, active and passive humidification devices have rapidly evolved. Sophisticated systems composed of reservoirs, wires, heating devices, and other elements have become part of our usual armamentarium in the intensive care unit. Therefore, basic knowledge of the mechanisms of action of each of these devices, as well as their advantages and disadvantages, becomes a necessity for the respiratory care and intensive care practitioner. In this paper, we review current methods of airway humidification during invasive mechanical ventilation of adult patients. We describe a variety of devices and describe the eventual applications according to specific clinical conditions.

  17. Glomerular filtration is reduced by high tidal volume ventilation in an in vivo healthy rat model

    Directory of Open Access Journals (Sweden)

    A. Luque

    2009-11-01

    Full Text Available Mechanical ventilation has been associated with organ failure in patients with acute respiratory distress syndrome. The present study examines the effects of tidal volume (V T on renal function using two V T values (8 and 27 mL/kg in anesthetized, paralyzed and mechanically ventilated male Wistar rats. Animals were randomized into two groups of 6 rats each: V T8 (V T, 8 mL/kg; 61.50 ± 0.92 breaths/min; positive end-expiratory pressure, 3.0 cmH2O; peak airway pressure (PAW, 11.8 ± 2.0 cmH2O, and V T27 (V T, 27 mL/kg; 33.60 ± 1.56 breaths/min; positive end-expiratory pressure, none, and PAW, 22.7 ± 4.0 cmH2O. Throughout the experiment, mean PAW remained comparable between the two groups (6.33 ± 0.21 vs 6.50 ± 0.22 cmH2O. For rats in the V T27 group, inulin clearance (mL·min-1·body weight-1 decreased acutely after 60 min of mechanical ventilation and even more significantly after 90 min, compared with baseline values (0.60 ± 0.05 and 0.45 ± 0.05 vs 0.95 ± 0.07; P < 0.001, although there were no differences between groups in mean arterial pressure or gasometric variables. In the V T8 group, inulin clearance at 120 min of mechanical ventilation remained unchanged in relation to baseline values (0.72 ± 0.03 vs 0.80 ± 0.05. The V T8 and V T27 groups did not differ in terms of serum thiobarbituric acid reactive substances (3.97 ± 0.27 vs 4.02 ± 0.45 nmol/mL or endothelial nitric oxide synthase expression (94.25 ± 2.75 vs 96.25 ± 2.39%. Our results show that glomerular filtration is acutely affected by high tidal volume ventilation but do not provide information about the mechanism.

  18. Comparison between Variable and Conventional Volume-Controlled Ventilation on Cardiorespiratory Parameters in Experimental Emphysema.

    Science.gov (United States)

    Henriques, Isabela; Padilha, Gisele A; Huhle, Robert; Wierzchon, Caio; Miranda, Paulo J B; Ramos, Isalira P; Rocha, Nazareth; Cruz, Fernanda F; Santos, Raquel S; de Oliveira, Milena V; Souza, Sergio A; Goldenberg, Regina C; Luiz, Ronir R; Pelosi, Paolo; de Abreu, Marcelo G; Silva, Pedro L; Rocco, Patricia R M

    2016-01-01

    Emphysema is characterized by loss of lung tissue elasticity and destruction of structures supporting alveoli and capillaries. The impact of mechanical ventilation strategies on ventilator-induced lung injury (VILI) in emphysema is poorly defined. New ventilator strategies should be developed to minimize VILI in emphysema. The present study was divided into two protocols: (1) characterization of an elastase-induced emphysema model in rats and identification of the time point of greatest cardiorespiratory impairment, defined as a high specific lung elastance associated with large right ventricular end-diastolic area; and (2) comparison between variable (VV) and conventional volume-controlled ventilation (VCV) on lung mechanics and morphometry, biological markers, and cardiac function at that time point. In the first protocol, Wistar rats (n = 62) received saline (SAL) or porcine pancreatic elastase (ELA) intratracheally once weekly for 4 weeks, respectively. Evaluations were performed 1, 3, 5, or 8 weeks after the last intratracheal instillation of saline or elastase. After identifying the time point of greatest cardiorespiratory impairment, an additional 32 Wistar rats were randomized into the SAL and ELA groups and then ventilated with VV or VCV (n = 8/group) [tidal volume (VT) = 6 mL/kg, positive end-expiratory pressure (PEEP) = 3 cmH2O, fraction of inspired oxygen (FiO2) = 0.4] for 2 h. VV was applied on a breath-to-breath basis as a sequence of randomly generated VT values (mean VT = 6 mL/kg), with a 30% coefficient of variation. Non-ventilated (NV) SAL and ELA animals were used for molecular biology analysis. The time point of greatest cardiorespiratory impairment, was observed 5 weeks after the last elastase instillation. At this time point, interleukin (IL)-6, cytokine-induced neutrophil chemoattractant (CINC)-1, amphiregulin, angiopoietin (Ang)-2, and vascular endothelial growth factor (VEGF) mRNA levels were higher in ELA compared to SAL. In ELA animals

  19. Comparison between Variable and Conventional Volume-Controlled Ventilation on Cardiorespiratory Parameters in Experimental Emphysema

    Science.gov (United States)

    Henriques, Isabela; Padilha, Gisele A.; Huhle, Robert; Wierzchon, Caio; Miranda, Paulo J. B.; Ramos, Isalira P.; Rocha, Nazareth; Cruz, Fernanda F.; Santos, Raquel S.; de Oliveira, Milena V.; Souza, Sergio A.; Goldenberg, Regina C.; Luiz, Ronir R.; Pelosi, Paolo; de Abreu, Marcelo G.; Silva, Pedro L.; Rocco, Patricia R. M.

    2016-01-01

    Emphysema is characterized by loss of lung tissue elasticity and destruction of structures supporting alveoli and capillaries. The impact of mechanical ventilation strategies on ventilator-induced lung injury (VILI) in emphysema is poorly defined. New ventilator strategies should be developed to minimize VILI in emphysema. The present study was divided into two protocols: (1) characterization of an elastase-induced emphysema model in rats and identification of the time point of greatest cardiorespiratory impairment, defined as a high specific lung elastance associated with large right ventricular end-diastolic area; and (2) comparison between variable (VV) and conventional volume-controlled ventilation (VCV) on lung mechanics and morphometry, biological markers, and cardiac function at that time point. In the first protocol, Wistar rats (n = 62) received saline (SAL) or porcine pancreatic elastase (ELA) intratracheally once weekly for 4 weeks, respectively. Evaluations were performed 1, 3, 5, or 8 weeks after the last intratracheal instillation of saline or elastase. After identifying the time point of greatest cardiorespiratory impairment, an additional 32 Wistar rats were randomized into the SAL and ELA groups and then ventilated with VV or VCV (n = 8/group) [tidal volume (VT) = 6 mL/kg, positive end-expiratory pressure (PEEP) = 3 cmH2O, fraction of inspired oxygen (FiO2) = 0.4] for 2 h. VV was applied on a breath-to-breath basis as a sequence of randomly generated VT values (mean VT = 6 mL/kg), with a 30% coefficient of variation. Non-ventilated (NV) SAL and ELA animals were used for molecular biology analysis. The time point of greatest cardiorespiratory impairment, was observed 5 weeks after the last elastase instillation. At this time point, interleukin (IL)-6, cytokine-induced neutrophil chemoattractant (CINC)-1, amphiregulin, angiopoietin (Ang)-2, and vascular endothelial growth factor (VEGF) mRNA levels were higher in ELA compared to SAL. In ELA animals

  20. Respiratory dynamics and dead space to tidal volume ratio of volume-controlled versus pressure-controlled ventilation during prolonged gynecological laparoscopic surgery.

    Science.gov (United States)

    Lian, Ming; Zhao, Xiao; Wang, Hong; Chen, Lianhua; Li, Shitong

    2016-12-30

    Laparoscopic operations have become longer and more complex and applied to a broader patient population in the last decades. Prolonged gynecological laparoscopic surgeries require prolonged pneumoperitoneum and Trendelenburg position, which can influence respiratory dynamics and other measurements of pulmonary function. We investigated the differences between volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) and tried to determine the more efficient ventilation mode during prolonged pneumoperitoneum in gynecological laparoscopy. Twenty-six patients scheduled for laparoscopic radical hysterectomy combined with or without laparoscopic pelvic lymphadenectomy were randomly allocated to be ventilated by either VCV or PCV. Standard anesthesic management and laparoscopic procedures were performed. Measurements of respiratory and hemodynamic dynamics were obtained after induction of anesthesia, at 10, 30, 60, and 120 min after establishing pneumoperitoneum, and at 10 min after return to supine lithotomy position and removal of carbon dioxide. The logistic regression model was applied to predict the corresponding critical value of duration of pneumoperitoneum when the Ppeak was higher than 40 cmH2O. Prolonged pneumoperitoneum and Trendelenburg position produced significant and clinically relevant changes in dynamic compliance and respiratory mechanics in anesthetized patients under PCV and VCV ventilation. Patients under PCV ventilation had a similar increase of dead space/tidal volume ratio, but had a lower Ppeak increase compared with those under VCV ventilation. The critical value of duration of pneumoperitoneum was predicted to be 355 min under VCV ventilation, corresponding to the risk of Ppeak higher than 40 cmH2O. Both VCV and PCV can be safely applied to prolonged gynecological laparoscopic surgery. However, PCV may become the better choice of ventilation after ruling out of other reasons for Ppeak increasing.

  1. [Hypercapnic respiratory failure. Pathophysiology, indications for mechanical ventilation and management].

    Science.gov (United States)

    Kreppein, U; Litterst, P; Westhoff, M

    2016-04-01

    Acute hypercapnic respiratory failure is mostly seen in patients with chronic obstructive pulmonary disease (COPD) and obesity hypoventilation syndrome (OHS). Depending on the underlying cause it may be associated with hypoxemic respiratory failure and places high demands on mechanical ventilation. Presentation of the current knowledge on indications and management of mechanical ventilation in patients with hypercapnic respiratory failure. Review of the literature. Important by the selection of mechanical ventilation procedures is recognition of the predominant pathophysiological component. In hypercapnic respiratory failure with a pH pathophysiological situation in patients with OHS or overlap syndrome. If severe respiratory acidosis and hypercapnia cannot be managed by mechanical ventilation therapy alone extracorporeal venous CO2 removal may be necessary. Reports on this approach in awake patients are available. The use of NIV is the predominant treatment in patients with hypercapnic respiratory failure but close monitoring is necessary in order not to miss the indications for intubation and invasive ventilation. Methods of extracorporeal CO2 removal especially in awake patients need further evaluation.

  2. Invasive home mechanical ventilation, mainly focused on neuromuscular disorders

    Directory of Open Access Journals (Sweden)

    Börger, Sandra

    2010-01-01

    Full Text Available Introduction and background: Invasive home mechanical ventilation is used for patients with chronic respiratory insufficiency. This elaborate and technology-dependent ventilation is carried out via an artificial airway (tracheal cannula to the trachea. Exact numbers about the incidence of home mechanical ventilation are not available. Patients with neuromuscular diseases represent a large portion of it. Research questions: Specific research questions are formulated and answered concerning the dimensions of medicine/nursing, economics, social, ethical and legal aspects. Beyond the technical aspect of the invasive home, mechanical ventilation, medical questions also deal with the patient’s symptoms and clinical signs as well as the frequency of complications. Economic questions pertain to the composition of costs and the differences to other ways of homecare concerning costs and quality of care. Questions regarding social aspects consider the health-related quality of life of patients and caregivers. Additionally, the ethical aspects connected to the decision of home mechanical ventilation are viewed. Finally, legal aspects of financing invasive home mechanical ventilation are discussed. Methods: Based on a systematic literature search in 2008 in a total of 31 relevant databases current literature is viewed and selected by means of fixed criteria. Randomized controlled studies, systematic reviews and HTA reports (health technology assessment, clinical studies with patient numbers above ten, health-economic evaluations, primary studies with particular cost analyses and quality-of-life studies related to the research questions are included in the analysis. Results and discussion: Invasive mechanical ventilation may improve symptoms of hypoventilation, as the analysis of the literature shows. An increase in life expectancy is likely, but for ethical reasons it is not confirmed by premium-quality studies. Complications (e. g. pneumonia are rare

  3. Mechanical ventilation: lessons from the ARDSNet trial

    Directory of Open Access Journals (Sweden)

    Marco Ranieri V

    2000-08-01

    Full Text Available Abstract The acute respiratory distress syndrome (ARDS is an inflammatory disease of the lungs characterized clinically by bilateral pulmonary infiltrates, decreased pulmonary compliance and hypoxemia. Although supportive care for ARDS seems to have improved over the past few decades, few studies have shown that any treatment can decrease mortality for this deadly syndrome. In the 4 May 2000 issue of New England Journal of Medicine, the results of an NIH-sponsored trial were presented; they demonstrated that the use of a ventilatory strategy that minimizes ventilator-induced lung injury leads to a 22% decrease in mortality. The implications of this study with respect to clinical practice, further ARDS studies and clinical research in the critical care setting are discussed.

  4. Effect of One-lung Ventilation with Pressure Control Ventilation-volume Guarantee on Respiratory Mechanics in Elderly Patients Undergoing Radical Esophageal Cancer Surgery%压力控制通气-容量保证单肺通气模式对老年食管癌根治术患者呼吸力学的影响

    Institute of Scientific and Technical Information of China (English)

    原皓; 邹亮; 孙莉

    2014-01-01

    To explore the effect of one-lung ventilation (OLV ) with pressure control ventilation-volume guarantee(PCV-VG) on respiratory mechanics in elderly patients undergoing radical esophageal cancer sur-gery .[Methods] Totally 40 elderly patients(ASA Ⅰ ~ Ⅱ) undergoing radical esophageal cancer surgery were di-vided into two groups with 20 in each .All patients were given sevoflurane inhalation for maintenance anesthesia and intubated with double lumen endotracheal catheter .Two-lung volume controlled ventilation(VCV) with a tidal volume(VT) of 10ml/kg and frequency(f) of 12 breaths per minute were performed before chest opening .After chest was opened ,OLV was performed .Group A received VCV mode with a VT of 8ml/kg and f of 12 breaths per minute .Group B received PCV-VG mode with the same peak airway pressure (Ppeak) as that during two-lung VCV ,VT of 8ml/kg and f of 12 breaths per minute .The VT ,minute volume(MV) ,Ppeak ,mean airway pres-sure(Pmean) ,end-tidal pressure of carbon dioxide (PET CO2 ) and dynamic lung compliance (Cdyn) before OLA (T1 ) ,30min after OLA(T2 ) ,60min after OLA(T3 ) and 30min after two-lung ventilation(TLA) were observed . Lung effective dynamic compliance(Cdyn) was calculated .[Results]Compared with group A ,Ppeak and Pmean in group B were decreased ,but there was no significant difference in VT ,MV and PET CO2 ,and Cdyn was increased .[Conclusion] PCV-VG mode in OLA for elderly patients undergoing radical esophageal cancer surgery can decrease Ppeak ,ensure ventilatory capacity and improve Cdyn ,so it is good for lung protection in elderly patients .%【目的】探讨压力控制通气-容量保证(PCV-VG)单肺通气(OLV)模式对老年食管癌根治术患者呼吸力学的影响。【方法】将40例行食管癌根治术的老年患者(ASA Ⅰ~Ⅱ级)分为两组,每组20例。所有患者采取七氟烷吸入维持麻醉,插入双腔气管导管。手术进胸前先行双肺定容通气(VCV

  5. Adequacy of oxygenation parameters in elderly patients undergoing mechanical ventilation

    OpenAIRE

    Guedes, Luana Petruccio Cabral Monteiro; Delfino,Fabrício Costa; de Faria, Flavia Perassa; de Melo, Gislane Ferreira; Carvalho, Gustavo Azevedo

    2013-01-01

    ABSTRACT Objective: To compare ideal PaO2 with PaO2 found, ideal PaO2/FiO2 of room air with the one found, and ideal FiO2 with FiO2 found in mechanically ventilated elderly patients. Methods: Cross-sectional study that evaluated elderly mechanically ventilated patients for at least 72 hours and who underwent three subsequent blood gas analyses. Results: The sample consisted of 48 elderly with mean age of 74.77±9.36 years. There was a significant difference between the ideal PaO2 and the one f...

  6. Conventional mechanical ventilation of healthy lungs induced pro-inflammatory cytokine gene transcription.

    Science.gov (United States)

    Brégeon, Fabienne; Roch, Antoine; Delpierre, Stéphane; Ghigo, Eric; Autillo-Touati, Amapola; Kajikawa, Osamu; Martin, Thomas R; Pugin, Jérôme; Portugal, Henry; Auffray, Jean-Pierre; Jammes, Yves

    2002-08-30

    We investigated the potential inflammatory reaction induced by mechanical ventilation (MV) using 10 ml/kg tidal volume and no positive end-expiratory pressure (PEEP) in control (C, n = 8), spontaneously breathing (SB, n = 12) and mechanically ventilated (MV, n = 12) rabbits with normal lungs. After 6 h (MV and SB groups) or immediately (C group), lungs were removed for measurement of wet-to-dry (W/D) weight ratio and for bronchoalveolar lavage (BAL). Pulmonary mechanics were also studied. MV animals developed a modest but significant (P transcription (mRNAs), without significant elevation of the corresponding protein cytokines in the BAL supernatant, except for MCP-1 (P < 0.05). These data suggest that MV, even using moderate tidal volume, elicits a pro-inflammatory stimulus to the lungs.

  7. Brazilian recommendations of mechanical ventilation 2013. Part 2

    Science.gov (United States)

    Barbas, Carmen Sílvia Valente; Ísola, Alexandre Marini; Farias, Augusto Manoel de Carvalho; Cavalcanti, Alexandre Biasi; Gama, Ana Maria Casati; Duarte, Antonio Carlos Magalhães; Vianna, Arthur; Serpa Neto, Ary; Bravim, Bruno de Arruda; Pinheiro, Bruno do Valle; Mazza, Bruno Franco; de Carvalho, Carlos Roberto Ribeiro; Toufen Júnior, Carlos; David, Cid Marcos Nascimento; Taniguchi, Corine; Mazza, Débora Dutra da Silveira; Dragosavac, Desanka; Toledo, Diogo Oliveira; Costa, Eduardo Leite; Caser, Eliana Bernadete; Silva, Eliezer; Amorim, Fabio Ferreira; Saddy, Felipe; Galas, Filomena Regina Barbosa Gomes; Silva, Gisele Sampaio; de Matos, Gustavo Faissol Janot; Emmerich, João Claudio; Valiatti, Jorge Luis dos Santos; Teles, José Mario Meira; Victorino, Josué Almeida; Ferreira, Juliana Carvalho; Prodomo, Luciana Passuello do Vale; Hajjar, Ludhmila Abrahão; Martins, Luiz Claudio; Malbouisson, Luis Marcelo Sá; Vargas, Mara Ambrosina de Oliveira; Reis, Marco Antonio Soares; Amato, Marcelo Brito Passos; Holanda, Marcelo Alcântara; Park, Marcelo; Jacomelli, Marcia; Tavares, Marcos; Damasceno, Marta Cristina Paulette; Assunção, Murillo Santucci César; Damasceno, Moyzes Pinto Coelho Duarte; Youssef, Nazah Cherif Mohamed; Teixeira, Paulo José Zimmermann; Caruso, Pedro; Duarte, Péricles Almeida Delfino; Messeder, Octavio; Eid, Raquel Caserta; Rodrigues, Ricardo Goulart; de Jesus, Rodrigo Francisco; Kairalla, Ronaldo Adib; Justino, Sandra; Nemer, Sergio Nogueira; Romero, Simone Barbosa; Amado, Verônica Moreira

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document. PMID:25295817

  8. Brazilian recommendations of mechanical ventilation 2013. Part I

    Science.gov (United States)

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document. PMID:25210957

  9. Lung mechanics in the TIMP3 null mouse and its response to mechanical ventilation.

    Science.gov (United States)

    Martin, Erica L; Truscott, Emily A; Bailey, Timothy C; Leco, Kevin J; McCaig, Lynda A; Lewis, James F; Veldhuizen, Ruud A W

    2007-03-01

    Tissue inhibitor of metalloproteinase-3 (TIMP3) null mice develop emphysema-like airspace enlargement due to an enzymatic imbalance. This study investigates how these abnormalities alter lung mechanics and the response to 2 different mechanical ventilation strategies. Phenotypically, TIMP3 null mice had increased compliance, and decreased resistance, tissue damping, and tissue elastance over wild-type controls. Decreased compliance and increased resistance were observed following the injurious ventilation strategy; however, the TIMP3 null response to both ventilation strategies was similar to wild-type mice. In conclusion, TIMP3 null mice have significant alterations in lung mechanics; however, this does not affect their response to ventilation.

  10. Mechanical Ventilation during Extracorporeal Membrane Oxygenation in Patients with Acute Severe Respiratory Failure

    Directory of Open Access Journals (Sweden)

    Zhongheng Zhang

    2017-01-01

    Full Text Available Conventionally, a substantial number of patients with acute respiratory failure require mechanical ventilation (MV to avert catastrophe of hypoxemia and hypercapnia. However, mechanical ventilation per se can cause lung injury, accelerating the disease progression. Extracorporeal membrane oxygenation (ECMO provides an alternative to rescue patients with severe respiratory failure that conventional mechanical ventilation fails to maintain adequate gas exchange. The physiology behind ECMO and its interaction with MV were reviewed. Next, we discussed the timing of ECMO initiation based on the risks and benefits of ECMO. During the running of ECMO, the protective ventilation strategy can be employed without worrying about catastrophic hypoxemia and carbon dioxide retention. There is a large body of evidence showing that protective ventilation with low tidal volume, high positive end-expiratory pressure, and prone positioning can provide benefits on mortality outcome. More recently, there is an increasing popularity on the use of awake and spontaneous breathing for patients undergoing ECMO, which is thought to be beneficial in terms of rehabilitation.

  11. Mechanical Ventilation during Extracorporeal Membrane Oxygenation in Patients with Acute Severe Respiratory Failure

    Science.gov (United States)

    Gu, Wan-Jie; Chen, Kun; Ni, Hongying

    2017-01-01

    Conventionally, a substantial number of patients with acute respiratory failure require mechanical ventilation (MV) to avert catastrophe of hypoxemia and hypercapnia. However, mechanical ventilation per se can cause lung injury, accelerating the disease progression. Extracorporeal membrane oxygenation (ECMO) provides an alternative to rescue patients with severe respiratory failure that conventional mechanical ventilation fails to maintain adequate gas exchange. The physiology behind ECMO and its interaction with MV were reviewed. Next, we discussed the timing of ECMO initiation based on the risks and benefits of ECMO. During the running of ECMO, the protective ventilation strategy can be employed without worrying about catastrophic hypoxemia and carbon dioxide retention. There is a large body of evidence showing that protective ventilation with low tidal volume, high positive end-expiratory pressure, and prone positioning can provide benefits on mortality outcome. More recently, there is an increasing popularity on the use of awake and spontaneous breathing for patients undergoing ECMO, which is thought to be beneficial in terms of rehabilitation. PMID:28127231

  12. Chest compression with a higher level of pressure support ventilation: effects on secretion removal, hemodynamics, and respiratory mechanics in patients on mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Wagner da Silva Naue

    2014-01-01

    Full Text Available OBJECTIVE: To determine the efficacy of chest compression accompanied by a 10-cmH2O increase in baseline inspiratory pressure on pressure support ventilation, in comparison with that of aspiration alone, in removing secretions, normalizing hemodynamics, and improving respiratory mechanics in patients on mechanical ventilation. METHODS: This was a randomized crossover clinical trial involving patients on mechanical ventilation for more than 48 h in the ICU of the Porto Alegre Hospital de Clínicas, in the city of Porto Alegre, Brazil. Patients were randomized to receive aspiration alone (control group or compression accompanied by a 10-cmH2O increase in baseline inspiratory pressure on pressure support ventilation (intervention group. We measured hemodynamic parameters, respiratory mechanics parameters, and the amount of secretions collected. RESULTS: We included 34 patients. The mean age was 64.2 ± 14.6 years. In comparison with the control group, the intervention group showed a higher median amount of secretions collected (1.9 g vs. 2.3 g; p = 0.004, a greater increase in mean expiratory tidal volume (16 ± 69 mL vs. 56 ± 69 mL; p = 0.018, and a greater increase in mean dynamic compliance (0.1 ± 4.9 cmH2O vs. 2.8 ± 4.5 cmH2O; p = 0.005. CONCLUSIONS: In this sample, chest compression accompanied by an increase in pressure support significantly increased the amount of secretions removed, the expiratory tidal volume, and dynamic compliance. (ClinicalTrials.gov Identifier:NCT01155648 [http://www.clinicaltrials.gov/

  13. The Mechanical Impact of Aerodynamic Stall on Tunnel Ventilation Fans

    Directory of Open Access Journals (Sweden)

    A. G. Sheard

    2012-01-01

    Full Text Available This paper describes work aimed at establishing the ability of a tunnel ventilation fan to operate without risk of mechanical failure in the event of aerodynamic stall. The research establishes the aerodynamic characteristics of a typical tunnel ventilation fan when operated in both stable and stalled aerodynamic conditions, with and without an anti-stall stabilisation ring, with and without a “nonstalling” blade angle and at full, half, and one quarter design speed. It also measures the fan’s peak stress, thus facilitating an analysis of the implications of the experimental results for mechanical design methodology. The paper concludes by presenting three different strategies for tunnel ventilation fan selection in applications where the selected fan will most likely stall. The first strategy selects a fan with a low-blade angle that is nonstalling. The second strategy selects a fan with a high-pressure developing capability. The third strategy selects a fan with a fitted stabilisation ring. Tunnel ventilation system designers each have their favoured fan selection strategy. However, all three strategies can produce system designs within which a tunnel ventilation fan performs reliably in-service. The paper considers the advantages and disadvantages of each selection strategy and considered the strengths and weaknesses of each.

  14. ICU Occupancy and mechanical ventilator use in the United States

    Science.gov (United States)

    Wunsch, Hannah; Wagner, Jason; Herlim, Maximilian; Chong, David; Kramer, Andrew; Halpern, Scott D.

    2013-01-01

    Objectives Detailed data on occupancy and use of mechanical ventilators in United States intensive care units (ICU) over time and across unit types, are lacking. We sought to describe the hourly bed occupancy and use of ventilators in US ICUs to improve future planning of both the routine and disaster provision of intensive care. Design Retrospective cohort study. We calculated mean hourly bed occupancy in each ICU and hourly bed occupancy for patients on mechanical ventilators. We assessed trends in overall occupancy over the three years. We also assessed occupancy and mechanical ventilation rates across different types and sizes of ICUs. Setting 97 US ICUs participating in Project IMPACT from 2005–07. Patients 226,942 consecutive admissions to ICUs. Interventions None. Measurements and Main Results Over the three years studied, total ICU occupancy ranged from 57.4% to 82.1% and the number of beds filled with mechanically ventilated patients ranged from 20.7% to 38.9%. There was no change in occupancy across years and no increase in occupancy during influenza seasons. Mean hourly occupancy across ICUs was 68.2% SD ± 21.3, and was substantially higher in ICUs with fewer beds (mean 75.8% (± 16.5) for 5–14 beds versus 60.9% (± 22.1) for 20+ beds, P = 0.001), and in academic hospitals (78.7% (± 15.9) versus 65.3% (± 21.3) for community not-for profit hospitals, P beds available more than half the time. The mean percentage of ICU patients receiving mechanical ventilation in any given hour was 39.5% (± 15.2), and a mean of 29.0% (± 15.9) of ICU beds were filled with a patient on a ventilator. Conclusions Occupancy of US ICUs was stable over time, but there is uneven distribution across different types and sizes of units. Only three out of ten beds were filled at any time with mechanically ventilated patients, suggesting substantial surge capacity throughout the system to care for acutely critically ill patients. PMID:23963122

  15. Comparison of volume controlled ventilation and pressure controlled ventilation in patients undergoing robot-assisted pelvic surgeries: An open-label trial

    Science.gov (United States)

    Jaju, Rishabh; Jaju, Pooja Bihani; Dubey, Mamta; Mohammad, Sadik; Bhargava, AK

    2017-01-01

    Background and Aims: Although volume controlled ventilation (VCV) has been the traditional mode of ventilation in robotic surgery, recently pressure controlled ventilation (PCV) has been used more frequently. However, evidence on whether PCV is superior to VCV is still lacking. We intended to compare the effects of VCV and PCV on respiratory mechanics and haemodynamic in patients undergoing robotic surgeries in steep Trendelenburg position. Methods: This prospective, randomized trial was conducted on sixty patients between 20 and 70 years belonging to the American Society of Anesthesiologist Physical Status I–II. Patients were randomly assigned to VCV group (n = 30), where VCV mode was maintained through anaesthesia, or the PCV group (n = 30), where ventilation mode was changed to PCV after the establishment of 40° Trendelenburg position and pneumoperitoneum. Respiratory (peak and mean airway pressure [APpeak, APmean], dynamic lung compliance [Cdyn] and arterial blood gas analysis) and haemodynamics variables (heart rate, mean blood pressure [MBP] central venous pressure) were measured at baseline (T1), post-Trendelenburg position at 60 min (T2), 120 min (T3) and after resuming supine position (T4). Results: Demographic profile, haemodynamic variables, oxygen saturation and minute ventilation (MV) were comparable between two groups. Despite similar values of APmean, APpeak was significantly higher in VCV group at T2 and T3 as compared to PCV group (P < 0.001). Cdyn and PaCO2 were also better in PCV group than in VCV group (P < 0.001 and 0.045, respectively). Conclusion: PCV should be preferred in robotic pelvic surgeries as it offers lower airway pressures, greater Cdyn and a better-preserved ventilation-perfusion matching for the same levels of MV. PMID:28216699

  16. Comparison of volume controlled ventilation and pressure controlled ventilation in patients undergoing robot-assisted pelvic surgeries: An open-label trial

    Directory of Open Access Journals (Sweden)

    Rishabh Jaju

    2017-01-01

    Full Text Available Background and Aims: Although volume controlled ventilation (VCV has been the traditional mode of ventilation in robotic surgery, recently pressure controlled ventilation (PCV has been used more frequently. However, evidence on whether PCV is superior to VCV is still lacking. We intended to compare the effects of VCV and PCV on respiratory mechanics and haemodynamic in patients undergoing robotic surgeries in steep Trendelenburg position. Methods: This prospective, randomized trial was conducted on sixty patients between 20 and 70 years belonging to the American Society of Anesthesiologist Physical Status I–II. Patients were randomly assigned to VCV group (n = 30, where VCV mode was maintained through anaesthesia, or the PCV group (n = 30, where ventilation mode was changed to PCV after the establishment of 40° Trendelenburg position and pneumoperitoneum. Respiratory (peak and mean airway pressure [APpeak, APmean], dynamic lung compliance [Cdyn] and arterial blood gas analysis and haemodynamics variables (heart rate, mean blood pressure [MBP] central venous pressure were measured at baseline (T1, post-Trendelenburg position at 60 min (T2, 120 min (T3 and after resuming supine position (T4. Results: Demographic profile, haemodynamic variables, oxygen saturation and minute ventilation (MV were comparable between two groups. Despite similar values of APmean,APpeakwas significantly higher in VCV group at T2 and T3 as compared to PCV group (P < 0.001. Cdynand PaCO2were also better in PCV group than in VCV group (P < 0.001 and 0.045, respectively. Conclusion: PCV should be preferred in robotic pelvic surgeries as it offers lower airway pressures, greater Cdynand a better-preserved ventilation-perfusion matching for the same levels of MV.

  17. Carbon monoxide transfer in pig lungs during mechanical ventilation

    NARCIS (Netherlands)

    F.C.A.M. te Nijenhuis (Frances)

    1996-01-01

    textabstractThis thesis comprises studies of gas transfer in the lungs during mechanical ventilation, which have been obtained in healthy pigs. The objectives of this thesis were: I) to adapt the breath-holding teclmique, as used during spontaneous breathing for estimation of gas transfer, to condit

  18. Liberation From Mechanical Ventilation in Critically Ill Adults

    DEFF Research Database (Denmark)

    Ouellette, Daniel R; Patel, Sheena; Girard, Timothy D

    2017-01-01

    BACKGROUND: An update of evidence-based guidelines concerning liberation from mechanical ventilation is needed as new evidence has become available. The American College of Chest Physicians (CHEST) and the American Thoracic Society (ATS) have collaborated to provide recommendations to clinicians ...

  19. Monitoring carbon dioxide in mechanically ventilated patients during hyperbaric treatment

    DEFF Research Database (Denmark)

    Bjerregård, Asger; Jansen, Erik

    2012-01-01

    Measurement of the arterial carbon dioxide (P(a)CO(2)) is an established part of the monitoring of mechanically ventilated patients. Other ways to get information about carbon dioxide in the patient are measurement of end-tidal carbon dioxide (P(ET)CO(2)) and transcutaneous carbon dioxide (PTCCO2...

  20. Respiratory mechanics in ventilated preterm infants : early determinants and outcome

    NARCIS (Netherlands)

    Snepvangers, Dimphn Adriana Cornelia Maria

    2004-01-01

    The studies in this thesis show that in the current surfactant era, the majority of ventilated preterm infants are still suffering from respiratory morbidity and substantial respiratory function abnormalities throughout the early years of life. Since respiratory function testing during mechanical ve

  1. Liberation From Mechanical Ventilation in Critically Ill Adults

    DEFF Research Database (Denmark)

    Schmidt, Gregory A; Girard, Timothy D; Kress, John P

    2017-01-01

    BACKGROUND: This clinical practice guideline addresses six questions related to liberation from mechanical ventilation in critically ill adults. It is the result of a collaborative effort between the American Thoracic Society (ATS) and the American College of Chest Physicians (CHEST). METHODS...

  2. Patients' experiences of being mechanically ventilated in an ICU

    DEFF Research Database (Denmark)

    Baumgarten, Mette; Poulsen, Ingrid

    2015-01-01

    patients admitted to an ICU, while they were not ventilated. RESULTS: Fifteen abstracted findings appeared from the metasynthesis and led to the synthesised finding: 'Being dependent on health professionals, without being able to communicate, causes experiences with anxiety, fear and loneliness. How......, consisting of anxiety, fear and loneliness. IMPLICATIONS FOR PRACTICE: In future practice, it is expected that patients will be more awake during mechanical ventilation. It is therefore important that health professionals have the knowledge that their presence and their support of the relationship between...

  3. Abdominal Muscle Activity during Mechanical Ventilation Increases Lung Injury in Severe Acute Respiratory Distress Syndrome.

    Directory of Open Access Journals (Sweden)

    Xianming Zhang

    Full Text Available It has proved that muscle paralysis was more protective for injured lung in severe acute respiratory distress syndrome (ARDS, but the precise mechanism is not clear. The purpose of this study was to test the hypothesis that abdominal muscle activity during mechanically ventilation increases lung injury in severe ARDS.Eighteen male Beagles were studied under mechanical ventilation with anesthesia. Severe ARDS was induced by repetitive oleic acid infusion. After lung injury, Beagles were randomly assigned into spontaneous breathing group (BIPAPSB and abdominal muscle paralysis group (BIPAPAP. All groups were ventilated with BIPAP model for 8h, and the high pressure titrated to reached a tidal volume of 6ml/kg, the low pressure was set at 10 cmH2O, with I:E ratio 1:1, and respiratory rate adjusted to a PaCO2 of 35-60 mmHg. Six Beagles without ventilator support comprised the control group. Respiratory variables, end-expiratory volume (EELV and gas exchange were assessed during mechanical ventilation. The levels of Interleukin (IL-6, IL-8 in lung tissue and plasma were measured by qRT-PCR and ELISA respectively. Lung injury scores were determined at end of the experiment.For the comparable ventilator setting, as compared with BIPAPSB group, the BIPAPAP group presented higher EELV (427±47 vs. 366±38 ml and oxygenation index (293±36 vs. 226±31 mmHg, lower levels of IL-6(216.6±48.0 vs. 297.5±71.2 pg/ml and IL-8(246.8±78.2 vs. 357.5±69.3 pg/ml in plasma, and lower express levels of IL-6 mRNA (15.0±3.8 vs. 21.2±3.7 and IL-8 mRNA (18.9±6.8 vs. 29.5±7.9 in lung tissues. In addition, less lung histopathology injury were revealed in the BIPAPAP group (22.5±2.0 vs. 25.2±2.1.Abdominal muscle activity during mechanically ventilation is one of the injurious factors in severe ARDS, so abdominal muscle paralysis might be an effective strategy to minimize ventilator-induce lung injury.

  4. Perceived decisional responsibility for mechanical ventilation and weaning

    DEFF Research Database (Denmark)

    Haugdahl, Hege S; Storli, Sissel; Rose, Louise

    2014-01-01

    AIM: To explore variability in perceptions of nurse managers and physician directors regarding roles, responsibilities and clinical-decision making related to mechanical ventilator weaning in Norwegian intensive care units (ICUs). BACKGROUND: Effective teamwork is crucial for providing optimal...... decisions higher than physician directors: median of 7 (IQR 5-8) (nurses) versus 5 (3-6) (physicians), (p collaborated in assessment of patient response to ventilator changes and titrating...... ventilator settings: 92% of nurses and 87% of physicians, (p = 0·46), and recognizing weaning failure 84% of nurses and 84% of physicians, (p = 0·96). Physician directors perceived significantly less collaborative decision-making on weaning method (p = 0·01), weaning readiness (p = 0·04) and readiness...

  5. Experimental Assessment of Mechanical Night Ventilation on Inner Wall Surfaces

    DEFF Research Database (Denmark)

    Wenhui, Ji; Heiselberg, Per Kvols; Wang, Houhua;

    2016-01-01

    The cooling potential of night ventilation largely depends on the heat exchange at the internal room surfaces. During night time, increased heat transfer on a vertical wall is expected due to cool supply air that flows along the internal wall surface from the top of the wall. This paper presents ...... an experimental study of the cooling of wall surfaces in a test room by mechanical night-time ventilation. Significant improvement of indoor thermal environment is presented resulting from the enhanced internal convection heat transfer.......The cooling potential of night ventilation largely depends on the heat exchange at the internal room surfaces. During night time, increased heat transfer on a vertical wall is expected due to cool supply air that flows along the internal wall surface from the top of the wall. This paper presents...

  6. A Survey of Mechanical Ventilator Practices Across Burn Centers in North America

    Science.gov (United States)

    Rhie, Ryan Y.; Lundy, Jonathan B.; Cartotto, Robert; Henderson, Elizabeth; Pressman, Melissa A.; Joe, Victor C.; Aden, James K.; Driscoll, Ian R.; Faucher, Lee D.; McDermid, Robert C.; Mlcak, Ronald P.; Hickerson, William L.; Jeng, James C.

    2016-01-01

    Burn injury introduces unique clinical challenges that make it difficult to extrapolate mechanical ventilator (MV) practices designed for the management of general critical care patients to the burn population. We hypothesize that no consensus exists among North American burn centers with regard to optimal ventilator practices. The purpose of this study is to examine various MV practice patterns in the burn population and to identify potential opportunities for future research. A researcher designed, 24-item survey was sent electronically to 129 burn centers. The χ2, Fisher’s exact, and Cochran–Mantel–Haenszel tests were used to determine if there were significant differences in practice patterns. We analyzed 46 questionnaires for a 36% response rate. More than 95% of the burn centers reported greater than 100 annual admissions. Pressure support and volume assist control were the most common initial MV modes used with or without inhalation injury. In the setting of Berlin defined mild acute respiratory distress syndrome (ARDS), ARDSNet protocol and optimal positive end-expiratory pressure were the top ventilator choices, along with fluid restriction/diuresis as a nonventilator adjunct. For severe ARDS, airway pressure release ventilation and neuromuscular blockade were the most popular. The most frequently reported time frame for mechanical ventilation before tracheostomy was 2 weeks (25 of 45, 55%); however, all respondents reported in the affirmative that there are certain clinical situations where early tracheostomy is warranted. Wide variations in clinical practice exist among North American burn centers. No single ventilator mode or adjunct prevails in the management of burn patients regardless of pulmonary insult. Movement toward American Burn Association–supported, multicenter studies to determine best practices and guidelines for ventilator management in burn patients is prudent in light of these findings. PMID:26135527

  7. Expression Changes of Early Response Genes in Lung Due to High Volume Ventilation

    Institute of Scientific and Technical Information of China (English)

    WANG Yuelan; YAO Shanglong; XIONG Ping

    2005-01-01

    Summary: The expression changes of early response genes due to ventilation with high volume in adult rats in vivo were observed. Forty SD male rats were randomly divided into control and 30, 60, 90 and 120 min ventilation groups, respectively (n=8 in each group). The animals were ventilated with tidal volume of 42 ml/kg and a PEEP level of 0 cmH2O at a rate of 40 breaths per minute in room air with a ventilator was given to the small animals. The expression of Egr-1, C-jun and IL-1β mRNA and proteins was detected by RT-PCR and immunohistochemical technique, respectively. The pathological changes in lung tissues were examined by HE staining. The results indicated that the expression of Egr-1, C-jun and IL-1β mRNA was detectable at 30th min after overventilation, but there was no significant difference in comparison with that in control group until overventilation for 60 min. However, at 90 and 120 min there was a significent increase as compared with 30 min or control group (P<0.05). The expression of Egr-1, C-jun and IL-1β deteced by immunohistochemical assay also showed a similar tendency of the gradual increase. In the 120 min ventilation group, the expression intensity of Egr-1, C-jun and IL-1β proteins in lung cells was the strongest and the nuclear translocation was increased markedly in comparison with any other groups (P<0.05). HE staining suggested that the degree of lung injury was aggravated gradually with the ventialtion going on and had a similar tendency to the expression of these early response genes and proteins. The current data suggested that overventilation activated and upregulated the expression of early response genes and the expression of these genes may be taken as the early signal to predict the onset and degree of lung injury. These results may demonstrated partially that the expression of early response genes induced by the mechanical stretch is associated with biochamic lung injury.

  8. Indicators of fatigue and of prolonged weaning from mechanical ventilation in surgical patients.

    Science.gov (United States)

    O'Keefe, G E; Hawkins, K; Boynton, J; Burns, D

    2001-01-01

    Indicators of weaning success have been tested primarily in patients who have been ventilated for short periods of time, and they may not be as accurate in cases where support has been required for longer than a few days. In patients requiring longer periods of support it is difficult to estimate the likelihood of successful liberation. Therefore we evaluated established weaning indices for their accuracy in surgical patients who required > or = 72 hours of mechanical ventilation. Surgical patients who required mechanical ventilation for > or = 72 hours were prospectively followed (over 6 months). We obtained standard indices of ventilatory function daily once patients were ready to wean. These indices included the respiratory rate/tidal volume ratio (RSBI), the maximal inspiratory pressure, and the minute ventilation. The duration of weaning and explicitly defined episodes of fatigue were the outcomes of interest. Statistical analyses evaluated the multiple factors that might influence the duration of weaning. Ninety-five patients (66% trauma; 34% surgery) survived to begin weaning, and 93% were liberated. The median duration of mechanical ventilation prior to weaning was 4 days (range 3-16 days), and the median duration of weaning was 3 days (range 0-56 days). Fatigue occurred in 36 patients and was not reliably predicted by any of the weaning measurements. However, a RSBI of > 105 on the first day of weaning was associated with prolonged weaning. By multivariate analysis, an RSBI of > 105 on the first day of weaning predicted prolonged weaning (hazard ratio 1.9; p = 0.03). After 72 hours of mechanical ventilation, clinical fatigue and successful liberation are not reliably predicted by standard indices of respiratory muscle strength and reserve. However, an RSBI of >105 observed once the patient is ready to wean is associated with prolonged weaning.

  9. Plasma-derived human C1-esterase inhibitor does not prevent mechanical ventilation-induced pulmonary complement activation in a rat model of Streptococcus pneumoniae pneumonia.

    Science.gov (United States)

    de Beer, F M; Aslami, H; Hoeksma, J; van Mierlo, G; Wouters, D; Zeerleder, S; Roelofs, J J T H; Juffermans, N P; Schultz, M J; Lagrand, W K

    2014-11-01

    Mechanical ventilation has the potential to cause lung injury, and the role of complement activation herein is uncertain. We hypothesized that inhibition of the complement cascade by administration of plasma-derived human C1-esterase inhibitor (C1-INH) prevents ventilation-induced pulmonary complement activation, and as such attenuates lung inflammation and lung injury in a rat model of Streptococcus pneumoniae pneumonia. Forty hours after intratracheal challenge with S. pneumoniae causing pneumonia rats were subjected to ventilation with lower tidal volumes and positive end-expiratory pressure (PEEP) or high tidal volumes without PEEP, after an intravenous bolus of C1-INH (200 U/kg) or placebo (saline). After 4 h of ventilation blood, broncho-alveolar lavage fluid and lung tissue were collected. Non-ventilated rats with S. pneumoniae pneumonia served as controls. While ventilation with lower tidal volumes and PEEP slightly amplified pneumonia-induced complement activation in the lungs, ventilation with higher tidal volumes without PEEP augmented local complement activation more strongly. Systemic pre-treatment with C1-INH, however, failed to alter ventilation-induced complement activation with both ventilation strategies. In accordance, lung inflammation and lung injury were not affected by pre-treatment with C1-INH, neither in rats ventilated with lower tidal volumes and PEEP, nor rats ventilated with high tidal volumes without PEEP. Ventilation augments pulmonary complement activation in a rat model of S. pneumoniae pneumonia. Systemic administration of C1-INH, however, does not attenuate ventilation-induced complement activation, lung inflammation, and lung injury.

  10. Complementary home mechanical ventilation techniques. SEPAR Year 2014.

    Science.gov (United States)

    Chiner, Eusebi; Sancho-Chust, José N; Landete, Pedro; Senent, Cristina; Gómez-Merino, Elia

    2014-12-01

    This is a review of the different complementary techniques that are useful for optimizing home mechanical ventilation (HMV). Airway clearance is very important in patients with HMV and many patients, particularly those with reduced peak cough flow, require airway clearance (manual or assisted) or assisted cough techniques (manual or mechanical) and suctioning procedures, in addition to ventilation. In the case of invasive HMV, good tracheostomy cannula management is essential for success. HMV patients may have sleep disturbances that must be taken into account. Sleep studies including complete polysomnography or respiratory polygraphy are helpful for identifying patient-ventilator asynchrony. Other techniques, such as bronchoscopy or nutritional support, may be required in patients on HMV, particularly if percutaneous gastrostomy is required. Information on treatment efficacy can be obtained from HMV monitoring, using methods such as pulse oximetry, capnography or the internal programs of the ventilators themselves. Finally, the importance of the patient's subjective perception is reviewed, as this may potentially affect the success of the HMV. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  11. Microbial profiling of dental plaque from mechanically ventilated patients.

    Science.gov (United States)

    Sands, Kirsty M; Twigg, Joshua A; Lewis, Michael A O; Wise, Matt P; Marchesi, Julian R; Smith, Ann; Wilson, Melanie J; Williams, David W

    2016-02-01

    Micro-organisms isolated from the oral cavity may translocate to the lower airways during mechanical ventilation (MV) leading to ventilator-associated pneumonia (VAP). Changes within the dental plaque microbiome during MV have been documented previously, primarily using culture-based techniques. The aim of this study was to use community profiling by high throughput sequencing to comprehensively analyse suggested microbial changes within dental plaque during MV. Bacterial 16S rDNA gene sequences were obtained from 38 samples of dental plaque sampled from 13 mechanically ventilated patients and sequenced using the Illumina platform. Sequences were processed using Mothur, applying a 97% gene similarity cut-off for bacterial species level identifications. A significant 'microbial shift' occurred in the microbial community of dental plaque during MV for nine out of 13 patients. Following extubation, or removal of the endotracheal tube that facilitates ventilation, sampling revealed a decrease in the relative abundance of potential respiratory pathogens and a compositional change towards a more predominantly (in terms of abundance) oral microbiota including Prevotella spp., and streptococci. The results highlight the need to better understand microbial shifts in the oral microbiome in the development of strategies to reduce VAP, and may have implications for the development of other forms of pneumonia such as community-acquired infection.

  12. The rapid shallow breathing index as a predictor of successful mechanical ventilation weaning: clinical utility when calculated from ventilator data

    Science.gov (United States)

    de Souza, Leonardo Cordeiro; Lugon, Jocemir Ronaldo

    2015-01-01

    ABSTRACT OBJECTIVE: The use of the rapid shallow breathing index (RSBI) is recommended in ICUs, where it is used as a predictor of mechanical ventilation (MV) weaning success. The aim of this study was to compare the performance of the RSBI calculated by the traditional method (described in 1991) with that of the RSBI calculated directly from MV parameters. METHODS: This was a prospective observational study involving patients who had been on MV for more than 24 h and were candidates for weaning. The RSBI was obtained by the same examiner using the two different methods (employing a spirometer and the parameters from the ventilator display) at random. In comparing the values obtained with the two methods, we used the Mann-Whitney test, Pearson's linear correlation test, and Bland-Altman plots. The performance of the methods was compared by evaluation of the areas under the ROC curves. RESULTS: Of the 109 selected patients (60 males; mean age, 62 ± 20 years), 65 were successfully weaned, and 36 died. There were statistically significant differences between the two methods for respiratory rate, tidal volume, and RSBI (p < 0.001 for all). However, when the two methods were compared, the concordance and the intra-observer variation coefficient were 0.94 (0.92-0.96) and 11.16%, respectively. The area under the ROC curve was similar for both methods (0.81 ± 0.04 vs. 0.82 ± 0.04; p = 0.935), which is relevant in the context of this study. CONCLUSIONS: The satisfactory performance of the RSBI as a predictor of weaning success, regardless of the method employed, demonstrates the utility of the method using the mechanical ventilator. PMID:26785962

  13. Parameter estimation of an artificial respiratory system under mechanical ventilation following a noisy regime

    Directory of Open Access Journals (Sweden)

    Marcus Henrique Victor Júnior

    Full Text Available Abstract Introduction: This work concerns the assessment of a novel system for mechanical ventilation and a parameter estimation method in a bench test. The tested system was based on a commercial mechanical ventilator and a personal computer. A computational routine was developed do drive the mechanical ventilator and a parameter estimation method was utilized to estimate positive end-expiratory pressure, resistance and compliance of the artificial respiratory system. Methods The computational routine was responsible for establishing connections between devices and controlling them. Parameters such as tidal volume, respiratory rate and others can be set for standard and noisy ventilation regimes. Ventilation tests were performed directly varying parameters in the system. Readings from a calibrated measuring device were the basis for analysis. Adopting a first-order linear model, the parameters could be estimated and the outcomes statistically analysed. Results Data acquisition was effective in terms of sample frequency and low noise content. After filtering, cycle detection and estimation took place. Statistics of median, mean and standard deviation were calculated, showing consistent matching with adjusted values. Changes in positive end-expiratory pressure statistically imply changes in compliance, but not the opposite. Conclusion The developed system was satisfactory in terms of clinical parameters. Statistics exhibited consistent relations between adjusted and estimated values, besides precision of the measurements. The system is expected to be used in animals, with a view to better understand the benefits of noisy ventilation, by evaluating the estimated parameters and performing cross relations among blood gas, ultrasonography and electrical impedance tomography.

  14. [Lung-brain interaction in the mechanically ventilated patient].

    Science.gov (United States)

    López-Aguilar, J; Fernández-Gonzalo, M S; Turon, M; Quílez, M E; Gómez-Simón, V; Jódar, M M; Blanch, L

    2013-10-01

    Patients with acute lung injury or acute respiratory distress syndrome (ARDS) admitted to the ICU present neuropsychological alterations, which in most cases extend beyond the acute phase and have an important adverse effect upon quality of life. The aim of this review is to deepen in the analysis of the complex interaction between lung and brain in critically ill patients subjected to mechanical ventilation. This update first describes the neuropsychological alterations occurring both during the acute phase of ICU stay and at discharge, followed by an analysis of lung-brain interactions during mechanical ventilation, and finally explores the etiology and mechanisms leading to the neurological disorders observed in these patients. The management of critical patients requires an integral approach focused on minimizing the deleterious effects over the short, middle or long term. Copyright © 2012 Elsevier España, S.L. y SEMICYUC. All rights reserved.

  15. Ventilation distribution and chest wall mechanics in microgravity

    Science.gov (United States)

    Paiva, M.; Wantier, M.; Verbanck, S.; Engel, L. A.; Prisk, G. K.; Guy, H. J. B.; West, J. B.

    1997-01-01

    The effect of gravity on lung ventilation distribution and the mechanisms of the chest wall were investigated. The following tests were performed with the respiratory monitoring system of the Anthorack, flown onboard Spacelab D2 mission: single breath washout (SBW), multiple breath washout (MBW) and argon rebreathing (ARB). In order to study chest wall mechanisms in microgravity, a respiratory inductive plethysmograph was used. The SBW tests did not reach statistical significance, while the ARB tests showed that gravity independent inhomogeneity of specific ventilation is larger than gravity dependent inhomogeneity. In which concerns the chest wall mechanisms, the analysis on the four astronauts during the normal respirations of the relaxation maneuver showed a 40 percent increase on the abdominal contribution to respiration.

  16. High-frequency oscillatory ventilation is not superior to conventional mechanical ventilation in surfactant-treated rabbits with lung injury

    NARCIS (Netherlands)

    D.A.M.P.J. Gommers (Diederik); A. Hartog (Anneke); R. Schnabel; A. de Jaegere (Anne); B.F. Lachmann (Burkhard)

    1999-01-01

    textabstractThe aim of this study was to compare high-frequency oscillatory ventilation (HFOV) with conventional mechanical ventilation (CMV) with and without surfactant in the treatment of surfactant-deficient rabbits. A previously described saline lung lavage model of

  17. Pulmonary levels of high-mobility group box 1 during mechanical ventilation and ventilator-associated pneumonia

    NARCIS (Netherlands)

    van Zoelen, Marieke A D; Ishizaka, Akitoshi; Wolthuls, Esther K; Choi, Goda; van der Poll, Tom; Schultz, Marcus J

    2008-01-01

    High-mobility group box (HMGB) 1 is a recently discovered proinflammatory mediator that contributes to acute lung injury. We determined HMGB-1 levels in bronchoalveolar lavage fluid of patients during mechanical ventilation (MV) and ventilator-associated pneumonia (VAP). Bronchoalveolar lavage fluid

  18. Effective sample size estimation for a mechanical ventilation trial through Monte-Carlo simulation: Length of mechanical ventilation and Ventilator Free Days.

    Science.gov (United States)

    Morton, S E; Chiew, Y S; Pretty, C; Moltchanova, E; Scarrott, C; Redmond, D; Shaw, G M; Chase, J G

    2017-02-01

    Randomised control trials have sought to seek to improve mechanical ventilation treatment. However, few trials to date have shown clinical significance. It is hypothesised that aside from effective treatment, the outcome metrics and sample sizes of the trial also affect the significance, and thus impact trial design. In this study, a Monte-Carlo simulation method was developed and used to investigate several outcome metrics of ventilation treatment, including 1) length of mechanical ventilation (LoMV); 2) Ventilator Free Days (VFD); and 3) LoMV-28, a combination of the other metrics. As these metrics have highly skewed distributions, it also investigated the impact of imposing clinically relevant exclusion criteria on study power to enable better design for significance. Data from invasively ventilated patients from a single intensive care unit were used in this analysis to demonstrate the method. Use of LoMV as an outcome metric required 160 patients/arm to reach 80% power with a clinically expected intervention difference of 25% LoMV if clinically relevant exclusion criteria were applied to the cohort, but 400 patients/arm if they were not. However, only 130 patients/arm would be required for the same statistical significance at the same intervention difference if VFD was used. A Monte-Carlo simulation approach using local cohort data combined with objective patient selection criteria can yield better design of ventilation studies to desired power and significance, with fewer patients per arm than traditional trial design methods, which in turn reduces patient risk. Outcome metrics, such as VFD, should be used when a difference in mortality is also expected between the two cohorts. Finally, the non-parametric approach taken is readily generalisable to a range of trial types where outcome data is similarly skewed.

  19. Postoperative Pulmonary Dysfunction and Mechanical Ventilation in Cardiac Surgery

    Directory of Open Access Journals (Sweden)

    Rafael Badenes

    2015-01-01

    Full Text Available Postoperative pulmonary dysfunction (PPD is a frequent and significant complication after cardiac surgery. It contributes to morbidity and mortality and increases hospitalization stay and its associated costs. Its pathogenesis is not clear but it seems to be related to the development of a systemic inflammatory response with a subsequent pulmonary inflammation. Many factors have been described to contribute to this inflammatory response, including surgical procedure with sternotomy incision, effects of general anesthesia, topical cooling, and extracorporeal circulation (ECC and mechanical ventilation (VM. Protective ventilation strategies can reduce the incidence of atelectasis (which still remains one of the principal causes of PDD and pulmonary infections in surgical patients. In this way, the open lung approach (OLA, a protective ventilation strategy, has demonstrated attenuating the inflammatory response and improving gas exchange parameters and postoperative pulmonary functions with a better residual functional capacity (FRC when compared with a conventional ventilatory strategy. Additionally, maintaining low frequency ventilation during ECC was shown to decrease the incidence of PDD after cardiac surgery, preserving lung function.

  20. Patient Machine Interface for the Control of Mechanical Ventilation Devices

    Directory of Open Access Journals (Sweden)

    Rolando Grave de Peralta

    2013-11-01

    Full Text Available The potential of Brain Computer Interfaces (BCIs to translate brain activity into commands to control external devices during mechanical ventilation (MV remains largely unexplored. This is surprising since the amount of patients that might benefit from such assistance is considerably larger than the number of patients requiring BCI for motor control. Given the transient nature of MV (i.e., used mainly over night or during acute clinical conditions, precluding the use of invasive methods, and inspired by current research on BCIs, we argue that scalp recorded EEG (electroencephalography signals can provide a non-invasive direct communication pathway between the brain and the ventilator. In this paper we propose a Patient Ventilator Interface (PVI to control a ventilator during variable conscious states (i.e., wake, sleep, etc.. After a brief introduction on the neural control of breathing and the clinical conditions requiring the use of MV we discuss the conventional techniques used during MV. The schema of the PVI is presented followed by a description of the neural signals that can be used for the on-line control. To illustrate the full approach, we present data from a healthy subject, where the inspiration and expiration periods during voluntary breathing were discriminated with a 92% accuracy (10-fold cross-validation from the scalp EEG data. The paper ends with a discussion on the advantages and obstacles that can be forecasted in this novel application of the concept of BCI.

  1. Actual performance of mechanical ventilators in ICU: a multicentric quality control study

    Directory of Open Access Journals (Sweden)

    Govoni L

    2012-12-01

    Full Text Available Leonardo Govoni,1 Raffaele L Dellaca,1 Oscar Peñuelas,2,3 Giacomo Bellani,4,5 Antonio Artigas,3,6 Miquel Ferrer,3,7 Daniel Navajas,3,8,9 Antonio Pedotti,1 Ramon Farré3,81TBM-Lab, Dipartimento di Bioingegneria, Politecnico di Milano University, Milano, Italy; 2Hospital Universitario de Getafe – CIBERES, Madrid, Spain; 3CIBER de Enfermedades Respiratorias, Bunyola, Spain; 4Department of Experimental Medicine, University of Milan, Bicocca, Italy; 5Department of Perioperative Medicine and Intensive Care, San Gerardo Hospital, Monza (MI, Italy; 6Critical Care Center, Sabadell Hospital, Corporació Sanitaria Universitaria Parc Tauli, Universitat Autonoma de Barcelona, CIBERES, Spain; 7Department of Pneumology, Hospital Clinic, IDIBAPS, Barcelona, Spain; 8Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universidad de Barcelona-IDIBAPS, Barcelona, Spain; 9Institut de Bioenginyeria de Catalunya, Barcelona, SpainAbstract: Even if the performance of a given ventilator has been evaluated in the laboratory under very well controlled conditions, inappropriate maintenance and lack of long-term stability and accuracy of the ventilator sensors may lead to ventilation errors in actual clinical practice. The aim of this study was to evaluate the actual performances of ventilators during clinical routines. A resistance (7.69 cmH2O/L/s – elastance (100 mL/cmH2O test lung equipped with pressure, flow, and oxygen concentration sensors was connected to the Y-piece of all the mechanical ventilators available for patients in four intensive care units (ICUs; n = 66. Ventilators were set to volume-controlled ventilation with tidal volume = 600 mL, respiratory rate = 20 breaths/minute, positive end-expiratory pressure (PEEP = 8 cmH2O, and oxygen fraction = 0.5. The signals from the sensors were recorded to compute the ventilation parameters. The average ± standard deviation and range (min–max of the ventilatory parameters were the following: inspired

  2. Spontaneous blood pressure oscillations in mechanically ventilated patients with sepsis

    DEFF Research Database (Denmark)

    Berg, Ronan M G; Plovsing, Ronni R; Greve, Anders M

    2016-01-01

    OBJECTIVE: In the present hypothesis-generating study, we investigated whether spontaneous blood pressure oscillations are suppressed to lower frequencies, and whether abolished oscillations are associated with an adverse outcome in mechanically ventilated patients with sepsis. METHODS: We...... retrospectively subjected invasive steady-state blood pressure recordings from 65 mechanically ventilated patients with sepsis to spectral analysis. Modified spectral bands were visually identified by plotting spectral power against frequency. RESULTS: Modified middle-frequency and low-frequency (MF' and LF......') oscillations were absent in 9% and 22% of the patients, respectively. In patients in whom spontaneous blood pressure oscillations were preserved, the MF' oscillations occurred at 0.021 Hz (median, interquartile range 0.013-0.030), whereas the LF' oscillations occurred at 0.009 Hz (median, interquartile range 0...

  3. Industrial Education Ventilation Study. Volume 1: Final Report.

    Science.gov (United States)

    Stanley Associates, Edmonton (Alberta).

    A study assessed aspects of ventilation in industrial education facilities in selected junior and senior highs schools in Alberta (Canada). This report describes the purpose of the study and the four test methods used to acquire school specific information. Also discussed are (1) the results of the instructors' perception survey, the ventilation…

  4. The Significance of Sedation Control in Patients Receiving Mechanical Ventilation

    OpenAIRE

    2012-01-01

    Background Adequate assessment and control of sedation play crucial roles in the proper performance of mechanical ventilation. Methods A total of 30 patients with various pulmonary diseases were prospectively enrolled. The study population was randomized into two groups. The sedation assessment group (SAG) received active protocol-based control of sedation, and in the empiric control group (ECG), the sedation levels were empirically adjusted. Subsequently, daily interruption of sedation (DIS)...

  5. Effect of regional lung inflation on ventilation heterogeneity at different length scales during mechanical ventilation of normal sheep lungs.

    Science.gov (United States)

    Wellman, Tyler J; Winkler, Tilo; Costa, Eduardo L V; Musch, Guido; Harris, R Scott; Venegas, Jose G; Vidal Melo, Marcos F

    2012-09-01

    Heterogeneous, small-airway diameters and alveolar derecruitment in poorly aerated regions of normal lungs could produce ventilation heterogeneity at those anatomic levels. We modeled the washout kinetics of (13)NN with positron emission tomography to examine how specific ventilation (sV) heterogeneity at different length scales is influenced by lung aeration. Three groups of anesthetized, supine sheep were studied: high tidal volume (Vt; 18.4 ± 4.2 ml/kg) and zero end-expiratory pressure (ZEEP) (n = 6); low Vt (9.2 ± 1.0 ml/kg) and ZEEP (n = 6); and low Vt (8.2 ± 0.2 ml/kg) and positive end-expiratory pressure (PEEP; 19 ± 1 cmH(2)O) (n = 4). We quantified fractional gas content with transmission scans, and sV with emission scans of infused (13)NN-saline. Voxel (13)NN-washout curves were fit with one- or two-compartment models to estimate sV. Total heterogeneity, measured as SD[log(10)(sV)], was divided into length-scale ranges by measuring changes in variance of log(10)(sV), resulting from progressive filtering of sV images. High-Vt ZEEP showed higher sV heterogeneity at 36-mm (r = -0.72) length scales (P < 0.001). We conclude that sV heterogeneity at length scales <60 mm increases in poorly aerated regions of mechanically ventilated normal lungs, likely due to heterogeneous small-airway narrowing and alveolar derecruitment. PEEP reduces sV heterogeneity by maintaining lung expansion and airway patency at those small length scales.

  6. Home Mechanical Ventilation: A Canadian Thoracic Society Clinical Practice Guideline

    Directory of Open Access Journals (Sweden)

    Douglas A McKim

    2011-01-01

    Full Text Available Increasing numbers of patients are surviving episodes of prolonged mechanical ventilation or benefitting from the recent availability of user-friendly noninvasive ventilators. Although many publications pertaining to specific aspects of home mechanical ventilation (HMV exist, very few comprehensive guidelines that bring together all of the current literature on patients at risk for or using mechanical ventilatory support are available. The Canadian Thoracic Society HMV Guideline Committee has reviewed the available English literature on topics related to HMV in adults, and completed a detailed guideline that will help standardize and improve the assessment and management of individuals requiring noninvasive or invasive HMV. The guideline provides a disease-specific review of illnesses including amyotrophic lateral sclerosis, spinal cord injury, muscular dystrophies, myotonic dystrophy, kyphoscoliosis, post-polio syndrome, central hypoventilation syndrome, obesity hypoventilation syndrome, and chronic obstructive pulmonary disease as well as important common themes such as airway clearance and the process of transition to home. The guidelines have been extensively reviewed by international experts, allied health professionals and target audiences. They will be updated on a regular basis to incorporate any new information.

  7. Hypervirulent Klebsiella pneumoniae induced ventilator-associated pneumonia in mechanically ventilated patients in China.

    Science.gov (United States)

    Yan, Q; Zhou, M; Zou, M; Liu, W-e

    2016-03-01

    The purpose of this study was to investigate the clinical characteristics of hypervirulent K. pneumoniae (hvKP) induced ventilator-associated pneumonia (VAP) and the microbiological characteristics and epidemiology of the hvKP strains. A retrospective study of 49 mechanically ventilated patients with K. pneumoniae induced VAP was conducted at a university hospital in China from January 2014 to December 2014. Clinical characteristics and K. pneumoniae antimicrobial susceptibility and biofilm formation were analyzed. Genes of capsular serotypes K1, K2, K5, K20, K54 and K57 and virulence factors plasmid rmpA(p-rmpA), iroB, iucA, mrkD, entB, iutA, ybtS, kfu and allS were also evaluated. Multilocus sequence typing (MLST) and random amplified polymorphic DNA (RAPD) analyses were used to study the clonal relationship of the K. pneumoniae strains. Strains possessed p-rmpA and iroB and iucA were defined as hvKP. Of 49 patients, 14 patients (28.6 %) were infected by hvKP. Antimicrobial resistant rate was significantly higher in cKP than that in hvKP. One ST29 K54 extended-spectrum-beta-lactamase (ESBL) producing hvKP strain was detected. The prevalence of K1 and K2 in hvKP was 42.9 % and 21.4 %, respectively. The incidences of K1, K2, K20, p-rmpA, iroB, iucA, iutA, Kfu and alls were significantly higher in hvKP than those in cKP. ST23 was dominant among hvKP strains, and all the ST23 strains had identical RAPD pattern. hvKP has become a common pathogen of VAP in mechanically ventilated patients in China. Clinicians should increase awareness of hvKP induced VAP and enhance epidemiologic surveillance.

  8. [Acute respiratory insufficiency due to COPD: invasive mechanical ventilation or not?].

    Science.gov (United States)

    Kant, K Merijn; Djamin, Remco S; Belderbos, Huub N A; van den Berg, Bart

    2014-01-01

    The decision to move to a form of mechanical ventilation in patients with acute respiratory failure due to an acute exacerbation of COPD is influenced by expectations about survival and quality of life after discharge from the ICU. Physicians tend to be too pessimistic about the survival outcome of an ICU stay with invasive mechanical ventilation. The forced expiratory volume in 1 second (FEV1) is not an adequate prognostic parameter. In order to prevent undertreatment of patients with respiratory failure due to an exacerbation of COPD, knowledge of prognostic parameters and quality of life in these patients is very important. End of life care should be integrated into the standard care of COPD patients.

  9. [Design of a lung simulator for teaching lung mechanics in mechanical ventilation].

    Science.gov (United States)

    Heili-Frades, Sarah; Peces-Barba, Germán; Rodríguez-Nieto, María Jesús

    2007-12-01

    Over the last 10 years, noninvasive ventilation has become a treatment option for respiratory insufficiency in pulmonology services. The technique is currently included in pulmonology teaching programs. Physicians and nurses should understand the devices they use and the interaction between the patient and the ventilator in terms of respiratory mechanics, adaptation, and synchronization. We present a readily assembled lung simulator for teaching purposes that is reproducible and interactive. Based on a bag-in-box system, this model allows the concepts of respiratory mechanics in mechanical ventilation to be taught simply and graphically in that it reproduces the patterns of restriction, obstruction, and the presence of leaks. It is possible to demonstrate how each ventilation parameter acts and the mechanical response elicited. It can also readily simulate asynchrony and demonstrate how this problem can be corrected.

  10. Assessing the influence of mechanical ventilation on blood gases and blood pressure in rattlesnakes

    DEFF Research Database (Denmark)

    Bertelsen, Mads F.; Buchanan, Rasmus; Jensen, Heidi M.

    2015-01-01

    , randomized trial. ANIMALS: Twenty one fasted adult South American rattlesnakes (Crotalus durissus terrificus). METHODS: Snakes were anesthetized with propofol (15 mg kg(-1) ) intravenously, endotracheally intubated and assigned to one of four ventilation regimens: Spontaneous ventilation, or mechanical...

  11. Effects of respiratory rate and tidal volume on gas exchange in total liquid ventilation.

    Science.gov (United States)

    Bull, Joseph L; Tredici, Stefano; Fujioka, Hideki; Komori, Eisaku; Grotberg, James B; Hirschl, Ronald B

    2009-01-01

    Using a rabbit model of total liquid ventilation (TLV), and in a corresponding theoretical model, we compared nine tidal volume-respiratory rate combinations to identify a ventilator strategy to maximize gas exchange, while avoiding choked flow, during TLV. Nine different ventilation strategies were tested in each animal (n = 12): low [LR = 2.5 breath/min (bpm)], medium (MR = 5 bpm), or high (HR = 7.5 bpm) respiratory rates were combined with a low (LV = 10 ml/kg), medium (MV = 15 ml/kg), or high (HV = 20 ml/kg) tidal volumes. Blood gases and partial pressures, perfluorocarbon gas content, and airway pressures were measured for each combination. Choked flow occurred in all high respiratory rate-high volume animals, 71% of high respiratory rate-medium volume (HRMV) animals, and 50% of medium respiratory rate-high volume (MRHV) animals but in no other combinations. Medium respiratory rate-medium volume (MRMV) resulted in the highest gas exchange of the combinations that did not induce choke. The HRMV and MRHV animals that did not choke had similar or higher gas exchange than MRMV. The theory predicted this behavior, along with spatial and temporal variations in alveolar gas partial pressures. Of the combinations that did not induce choked flow, MRMV provided the highest gas exchange. Alveolar gas transport is diffusion dominated and rapid during gas ventilation but is convection dominated and slow during TLV. Consequently, the usual alveolar gas equation is not applicable for TLV.

  12. The role of endocrine mechanisms in ventilator-associated lung injury in critically ill patients.

    Science.gov (United States)

    Penesova, A; Galusova, A; Vigas, M; Vlcek, M; Imrich, R; Majek, M

    2012-07-01

    The critically ill subjects are represented by a heterogeneous group of patients suffering from a life-threatening event of different origin, e.g. trauma, cardiopulmonary failure, surgery or sepsis. The majority of these patients are dependent on the artificial lung ventilation, which means a life-saving chance for them. However, the artificial lung ventilation may trigger ventilation-associated lung injury (VALI). The mechanical ventilation at higher volumes (volutrauma) and pressure (barotrauma) can cause histological changes in the lungs including impairments in the gap and adherens junctions and desmosomes. The injured lung epithelium may lead to an impairment of the surfactant production and function, and this may not only contribute to the pathophysiology of VALI but also to acute respiratory distress syndrome. Other components of VALI are atelectrauma and toxic effects of the oxygen. Collectively, all these effects may result in a lung inflammation associated with a subsequent profibrotic changes, endothelial dysfunction, and activation of the local and systemic endocrine responses such as the renin-angiotensin system (RAS). The present review is aimed to describe some of the pathophysiologic aspects of VALI providing a basis for novel therapeutic strategies in the critically ill patients.

  13. Pulmonary deposition of a nebulised aerosol during mechanical ventilation.

    Science.gov (United States)

    Thomas, S H; O'Doherty, M J; Fidler, H M; Page, C J; Treacher, D F; Nunan, T O

    1993-01-01

    BACKGROUND: There is increasing use of therapeutic aerosols in patients undergoing mechanical ventilation. Few studies have measured aerosol delivery to the lungs under these conditions with adequate experimental methods. Hence this study was performed to measure pulmonary aerosol deposition and to determine the reproducibility of the method of measurement during mechanical ventilation. METHODS: Nine male patients were studied during mechanical ventilation after open heart surgery and two experiments were performed in each to determine the reproducibility of the method. A solution of technetium-99m labelled human serum albumin (99mTc HSA (50 micrograms); activity in experiment 1, 74 MBq; in experiment 2, 185 MBq) in 3 ml saline was administered with a Siemens Servo 945 nebuliser system (high setting) and a System 22 Acorn nebuliser unit. Pulmonary deposition was quantified by means of a gamma camera and corrections derived from lung phantom studies. RESULTS: Pulmonary aerosol deposition was completed in 22 (SD 4) minutes. Total pulmonary deposition (% nebuliser dose (SD)) was 2.2 (0.8)% with 1.5% and 0.7% depositing in the right and left lungs respectively; 0.9% of the nebuliser activity was detected in the endotracheal tube or trachea and 51% was retained within the nebuliser unit. Considerable variability between subjects was found for total deposition (coefficient of variation (CV) 46%), but within subject reproducibility was good (CV 15%). CONCLUSIONS: Administration of aerosol in this way is inefficient and further research is needed to find more effective alternatives in patients who require mechanical respiratory support. This method of measurement seems suitable for the assessment of new methods of aerosol delivery in these patients. Images PMID:8493630

  14. Communication of mechanically ventilated patients in intensive care units

    Science.gov (United States)

    Martinho, Carina Isabel Ferreira; Rodrigues, Inês Tello Rato Milheiras

    2016-01-01

    Objective The aim of this study was to translate and culturally and linguistically adapt the Ease of Communication Scale and to assess the level of communication difficulties for patients undergoing mechanical ventilation with orotracheal intubation, relating these difficulties to clinical and sociodemographic variables. Methods This study had three stages: (1) cultural and linguistic adaptation of the Ease of Communication Scale; (2) preliminary assessment of its psychometric properties; and (3) observational, descriptive-correlational and cross-sectional study, conducted from March to August 2015, based on the Ease of Communication Scale - after extubation answers and clinical and sociodemographic variables of 31 adult patients who were extubated, clinically stable and admitted to five Portuguese intensive care units. Results Expert analysis showed high agreement on content (100%) and relevance (75%). The pretest scores showed a high acceptability regarding the completion of the instrument and its usefulness. The Ease of Communication Scale showed excellent internal consistency (0.951 Cronbach's alpha). The factor analysis explained approximately 81% of the total variance with two scale components. On average, the patients considered the communication experiences during intubation to be "quite hard" (2.99). No significant correlation was observed between the communication difficulties reported and the studied sociodemographic and clinical variables, except for the clinical variable "number of hours after extubation" (p < 0.05). Conclusion This study translated and adapted the first assessment instrument of communication difficulties for mechanically ventilated patients in intensive care units into European Portuguese. The preliminary scale validation suggested high reliability. Patients undergoing mechanical ventilation reported that communication during intubation was "quite hard", and these communication difficulties apparently existed regardless of the

  15. Instantaneous responses to high-frequency chest wall oscillation in patients with acute pneumonic respiratory failure receiving mechanical ventilation

    Science.gov (United States)

    Chuang, Ming-Lung; Chou, Yi-Ling; Lee, Chai-Yuan; Huang, Shih-Feng

    2017-01-01

    Abstract Background: Endotracheal intubation and prolonged immobilization of patients receiving mechanical ventilation may reduce expectoration function. High-frequency chest wall oscillation (HFCWO) may ameliorate airway secretion movement; however, the instantaneous changes in patients’ cardiopulmonary responses are unknown. Moreover, HFCWO may influence ventilator settings by the vigorous oscillation. The aim of this study was to investigate these issues. Methods: Seventy-three patients (52 men) aged 71.5 ± 13.4 years who were intubated with mechanical ventilation for pneumonic respiratory failure were recruited and randomly classified into 2 groups (HFCWO group, n = 36; and control group who received conventional chest physical therapy (CCPT, n = 37). HFCWO was applied with a fixed protocol, whereas CCPT was conducted using standard protocols. Both groups received sputum suction after the procedure. Changes in ventilator settings and the subjects’ responses were measured at preset intervals and compared within groups and between groups. Results: Oscillation did not affect the ventilator settings (all P > 0.05). The mean airway pressure, breathing frequency, and rapid shallow breathing index increased, and the tidal volume and SpO2 decreased (all P < 0.05). After sputum suction, the peak airway pressure (Ppeak) and minute ventilation decreased (all P < 0.05). The HFCWO group had a lower tidal volume and SpO2 at the end of oscillation, and lower Ppeak and tidal volume after sputum suction than the CCPT group. Conclusions: HFCWO affects breathing pattern and SpO2 but not ventilator settings, whereas CCPT maintains a steadier condition. After sputum suction, HFCWO slightly improved Ppeak compared to CCPT, suggesting that the study extends the indications of HFCWO for these patients in intensive care unit. (ClinicalTrials.gov number NCT02758106, retrospectively registered.) PMID:28248854

  16. Inhibition of Janus kinase signaling during controlled mechanical ventilation prevents ventilation-induced diaphragm dysfunction.

    Science.gov (United States)

    Smith, Ira J; Godinez, Guillermo L; Singh, Baljit K; McCaughey, Kelly M; Alcantara, Raniel R; Gururaja, Tarikere; Ho, Melissa S; Nguyen, Henry N; Friera, Annabelle M; White, Kathy A; McLaughlin, John R; Hansen, Derek; Romero, Jason M; Baltgalvis, Kristen A; Claypool, Mark D; Li, Wei; Lang, Wayne; Yam, George C; Gelman, Marina S; Ding, Rongxian; Yung, Stephanie L; Creger, Daniel P; Chen, Yan; Singh, Rajinder; Smuder, Ashley J; Wiggs, Michael P; Kwon, Oh-Sung; Sollanek, Kurt J; Powers, Scott K; Masuda, Esteban S; Taylor, Vanessa C; Payan, Donald G; Kinoshita, Taisei; Kinsella, Todd M

    2014-07-01

    Controlled mechanical ventilation (CMV) is associated with the development of diaphragm atrophy and contractile dysfunction, and respiratory muscle weakness is thought to contribute significantly to delayed weaning of patients. Therefore, therapeutic strategies for preventing these processes may have clinical benefit. The aim of the current study was to investigate the role of the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in CMV-mediated diaphragm wasting and weakness in rats. CMV-induced diaphragm atrophy and contractile dysfunction coincided with marked increases in STAT3 phosphorylation on both tyrosine 705 (Tyr705) and serine 727 (Ser727). STAT3 activation was accompanied by its translocation into mitochondria within diaphragm muscle and mitochondrial dysfunction. Inhibition of JAK signaling during CMV prevented phosphorylation of both target sites on STAT3, eliminated the accumulation of phosphorylated STAT3 within the mitochondria, and reversed the pathologic alterations in mitochondrial function, reduced oxidative stress in the diaphragm, and maintained normal diaphragm contractility. In addition, JAK inhibition during CMV blunted the activation of key proteolytic pathways in the diaphragm, as well as diaphragm atrophy. These findings implicate JAK/STAT3 signaling in the development of diaphragm muscle atrophy and dysfunction during CMV and suggest that the delayed extubation times associated with CMV can be prevented by inhibition of Janus kinase signaling.-Smith, I. J., Godinez, G. L., Singh, B. K., McCaughey, K. M., Alcantara, R. R., Gururaja, T., Ho, M. S., Nguyen, H. N., Friera, A. M., White, K. A., McLaughlin, J. R., Hansen, D., Romero, J. M., Baltgalvis, K. A., Claypool, M. D., Li, W., Lang, W., Yam, G. C., Gelman, M. S., Ding, R., Yung, S. L., Creger, D. P., Chen, Y., Singh, R., Smuder, A. J., Wiggs, M. P., Kwon, O.-S., Sollanek, K. J., Powers, S. K., Masuda, E. S., Taylor, V. C., Payan, D. G

  17. Ventilator Circuits, Humidification and Ventilator-Associated Pneumonia

    Directory of Open Access Journals (Sweden)

    Dean Hess

    1996-01-01

    Full Text Available Technical issues in the care of mechanically ventilated patients include those related to the ventilator circuit, humidification and ventilator-associated pneumonia. Principal issues related to ventilator circuits include leaks and compression volume. Circuit compression volume affects delivered tidal volume as well as measurements of auto-positive end-expiratory pressure and mixed expired PCO2. Resistance through the ventilator circuit contributes to patient-ventilator dyssynchrony during assisted modes of mechanical ventilation. Adequate humidification of inspired gas is necessary to prevent heat and moisture loss. Common methods of humidification of inspired gas during mechanical ventilation include use of active heated humidifiers and passive artificial noses. Artificial noses are less effective than active humidifiers and are best suited to short term use. With active humidifiers, the circuit can be heated to avoid condensate formation. However, care must be exercised when heated circuits are used to avoid delivery of a low relative humidity and subsequent drying of secretions in the artificial airway. Although pneumonia is a complication of mechanical ventilation, these pneumonias are usually the result of aspiration of pharyngeal secretions and are seldom related to the ventilator circuit. Ventilator circuits do not need to be changed more frequently than weekly for infection control purposes, and the incidence of ventilator-associated pneumonia may be greater with more frequent circuit changes.

  18. Mechanical ventilation weaning protocol improves medical adherence and results.

    Science.gov (United States)

    Borges, Luís Guilherme Alegretti; Savi, Augusto; Teixeira, Cassiano; de Oliveira, Roselaine Pinheiro; De Camillis, Marcio Luiz Ferreira; Wickert, Ricardo; Brodt, Sérgio Fernando Monteiro; Tonietto, Túlio Frederico; Cremonese, Ricardo; da Silva, Leonardo Silveira; Gehm, Fernanda; Oliveira, Eubrando Silvestre; Barth, Jose Herve Diel; Macari, Juçara Gasparetto; de Barros, Cíntia Dias; Vieira, Sílvia Regina Rios

    2017-10-01

    Implementation of a weaning protocol is related to better patient prognosis. However, new approaches may take several years to become the standard of care in daily practice. We conducted a prospective cohort study to investigate the effectiveness of a multifaceted strategy to implement a protocol to wean patients from mechanical ventilation (MV) and to evaluate the weaning success rate as well as practitioner adherence to the protocol. We investigated all consecutive MV-dependent subjects admitted to a medical-surgical intensive care unit (ICU) for >24h over 7years. The multifaceted strategy consisted of continuing education of attending physicians and ICU staff and regular feedback regarding patient outcomes. The study was conducted in three phases: protocol development, protocol and multifaceted strategy implementation, and protocol monitoring. Data regarding weaning outcomes and physician adherence to the weaning protocol were collected during all phases. We enrolled 2469 subjects over 7years, with 1,943 subjects (78.7%) experiencing weaning success. Physician adherence to the protocol increased during the years of protocol and multifaceted strategy implementation (from 38% to 86%, p<0.01) and decreased in the protocol monitoring phase (from 73.9% to 50.0%, p<0.01). However, during the study years, the weaning success of all subjects increased (from 73.1% to 85.4%, p<0.001). When the weaning protocol was evaluated step-by-step, we found high adherence for noninvasive ventilation use (95%) and weaning predictor measurement (91%) and lower adherence for control of fluid balance (57%) and daily interruption of sedation (24%). Weaning success was higher in patients who had undergone the weaning protocol compared to those who had undergone weaning based in clinical practice (85.6% vs. 67.7%, p<0.001). A multifaceted strategy consisting of continuing education and regular feedback can increase physician adherence to a weaning protocol for mechanical ventilation

  19. Cisapride decreases gastric content aspiration in mechanically ventilated patients

    Science.gov (United States)

    Pneumatikos, John; Koulouras, Basil; Frangides, Christ; Goe, Dian; Nakos, George

    1999-01-01

    Objective: To determine the effect of the prokinetic agent cisapride in the prevention of aspiration of gastric contents. Design: A prospective randomized two-period crossover study. Setting: Fourteen-bed polyvalent intensive care unit in a University Hospital. Patients: Eighteen intubated, mechanically ventilated patients who were seated in a semirecumbent position were studied. Method: Tc-99 m sulfur colloid (80 megabecquerels) was administered via nasogastric tube on 2 consecutive days. Patients randomly received cisapride (10 mg, via nasogastric tube) one day and a placebo the other. Bronchial secretions were obtained before and for 5 consecutive h after Tc-99 m administration. The radioactivity was measured in a standard amount (1ml) of bronchial fluid using a gamma counter and expressed as counts per min (cpm) after correction for decay. Results: Sixteen out of 18 (88%) patients had increased radioactivity in bronchial secretions. The radioactivity increased over time both with and without cisapride, although it was lower in patients receiving cisapride than in those receiving a placebo. The cumulative bronchial secretion radioactivity obtained when patients received cisapride was significantly lower than when patients received a placebo: 7540 ± 5330 and 21965 ± 16080 cpm, respectively (P <0.05). Conclusion: Our results suggest that aspiration of gastric contents exists even in patients who are kept in a semirecumbent position. Moreover, cisapride decreases the amount of gastric contents aspiration in intubated and mechanically ventilated patients and may play a role in the prevention of ventilator associated pneumonia. Cisapride, even with the patient in the semirecumbent position, did not completely prevent gastric content aspiration. PMID:11056722

  20. Carbon dioxide elimination and oxygen consumption in mechanically ventilated children.

    Science.gov (United States)

    Smallwood, Craig D; Walsh, Brian K; Bechard, Lori J; Mehta, Nilesh M

    2015-05-01

    Accurate measurement of carbon dioxide elimination (V̇CO2 ) and oxygen consumption (V̇O2 ) at the bedside may help titrate nutritional and respiratory support in mechanically ventilated patients. Continuous V̇CO2 monitoring is now available with many ventilators. However, because normative data are sparsely available in the literature, we aimed to describe the range of V̇CO2 and V̇O2 values observed in mechanically ventilated children. We also aimed to examine the characteristics of V̇CO2 values that are associated with standard steady state (5-min period when V̇CO2 and V̇O2 variability are 8 y, the mean V̇CO2 values were 7.6, 5.8, and 3.5 mL/kg/min. Normalized V̇CO2 and V̇O2 values were inversely related to subject height and age. The relationships between normalized gas exchange values and height were demonstrated by the models: V̇CO2 = 115 × (height in cm)(-0.71) (R = 0.61, P < .001) and V̇O2 = 130 × (height in cm)(-0.72) (R = 0.61, P < .001). Steady-state V̇CO2 predicted standard steady state (sensitivity of 0.84, specificity of 1.0, P < .01). V̇CO2 and V̇O2 measurements correlated with subject height and age. Smaller and younger subjects produced larger amounts of CO2 and consumed more O2 per unit of body weight. The use of a 5-min period when V̇CO2 varied by < 5% predicted standard steady state. Our observations may facilitate greater utility of V̇CO2 at the bedside in the pediatric ICU and thereby extend the benefits of metabolic monitoring to a larger group of patients. Copyright © 2015 by Daedalus Enterprises.

  1. Quality of life of ALS and LIS patients with and without invasive mechanical ventilation.

    Science.gov (United States)

    Rousseau, Marie-Christine; Pietra, Stéphane; Blaya, José; Catala, Anne

    2011-10-01

    There are very few studies where quality of life (QOL) is assessed in patients with complete physical and functional disability and dependence to invasive mechanical ventilation (IV). We compared QOL of amyotrophic lateral sclerosis (ALS) and locked-in-syndrome (LIS) patients with invasive mechanical ventilation to ALS and LIS patients without mechanical invasive ventilation. Thirty-four patients, 27 with ALS and seven with LIS (vascular or tumoral aetiology) were included in the study. Twelve had invasive ventilation, 22 had non-invasive ventilation, and in the non-invasive ventilation group, five of them had ventilation via mask. The following scales were used for patients: ALS Functional Rating Scale (ALSFRS), McGILL, Short-Form 36 (SF36), Beck Depression Inventory-II, the Toronto Alexithymia Scale and the anxiety inventory of Spielberger. Mean ALSFRS scores were significantly lower in the invasive ventilation group (IV) than in the non-invasive ventilation group. McGILL and SF36 were not significantly different between the IV group and the non-invasive ventilation group; there were no significant differences between the two groups for others scales either. Comparison between IV group and LIS without invasive mechanical ventilation revealed no significant difference for SF36 and McGILL QOL scores. QOL was not significantly different between the IV and not invasively ventilated patients, but ALSFRS was significantly lower in the IV group, and comparison of QOL scores between non-ventilated LIS patients who had the same score of dependence that invasively ventilated patients did not show any difference. Invasive mechanical ventilation for patients who accept tracheotomy allows life prolongation and their QOL is not affected; medical teams should be aware of that.

  2. Volume and Pressure Delivery During Pediatric High-Frequency Oscillatory Ventilation.

    Science.gov (United States)

    Wong, Ronald; Deakers, Timothy; Hotz, Justin; Khemani, Robinder G; Ross, Patrick A; Newth, Christopher J

    2017-04-01

    Identify variables independently associated with delivered tidal volume (VT) and measured mean airway pressure during high-frequency oscillatory ventilation across the range of pediatric endotracheal tube sizes. In vitro study. Research laboratory. An in vitro bench model of the intubated pediatric respiratory system during high-frequency oscillatory ventilation was used to obtain delivered VT and mean airway pressure (in the distal lung) for various endotracheal tube sizes. Measurements were taken at different combinations of ventilator set mean airway pressure (Paw), amplitude (ΔP), frequency, and test lung compliance. Multiple regression analysis was used to construct multivariable models predicting delivered VT and mean airway pressure. Variables independently associated with higher delivered VT for all endotracheal tube sizes include higher ΔP (p frequency (p frequency and ΔP magnifies the delivered VT when ΔP is high and frequency is low (p frequency increases (p frequency in delivered VT and the effect of ΔP and frequency on delivered mean airway pressure. These results demonstrate the need to measure or estimate VT and delivered pressures during high-frequency oscillatory ventilation and may be useful in determining optimal strategies for lung protective ventilation during high-frequency oscillatory ventilation.

  3. Prolonged mechanical ventilation induces cell cycle arrest in newborn rat lung

    NARCIS (Netherlands)

    Kroon, A.A.; Wang, J.; Kavanagh, B.; Huang, Z.; Kuliszewski, M.; van Goudoever, J.B.; Post, M.

    2011-01-01

    The molecular mechanism(s) by which mechanical ventilation disrupts alveolar development, a hallmark of bronchopulmonary dysplasia, is unknown. To determine the effect of 24 h of mechanical ventilation on lung cell cycle regulators, cell proliferation and alveolar formation in newborn rats.

  4. Prolonged mechanical ventilation induces cell cycle arrest in newborn rat lung

    NARCIS (Netherlands)

    A.A. Kroon (Abraham); J. Wang (Jinxia); B. Kavanagh (Brian); Z. Huang (Zhen); M. Kuliszewski (Maciej); J.B. van Goudoever (Hans); M.R. Post (Martin)

    2011-01-01

    textabstractRationale: The molecular mechanism(s) by which mechanical ventilation disrupts alveolar development, a hallmark of bronchopulmonary dysplasia, is unknown. Objective: To determine the effect of 24 h of mechanical ventilation on lung cell cycle regulators, cell proliferation and alveolar f

  5. Effects of surfactant depletion on regional pulmonary metabolic activity during mechanical ventilation.

    Science.gov (United States)

    de Prost, Nicolas; Costa, Eduardo L; Wellman, Tyler; Musch, Guido; Winkler, Tilo; Tucci, Mauro R; Harris, R Scott; Venegas, Jose G; Vidal Melo, Marcos F

    2011-11-01

    Inflammation during mechanical ventilation is thought to depend on regional mechanical stress. This can be produced by concentration of stresses and cyclic recruitment in low-aeration dependent lung. Positron emission tomography (PET) with (18)F-fluorodeoxyglucose ((18)F-FDG) allows for noninvasive assessment of regional metabolic activity, an index of neutrophilic inflammation. We tested the hypothesis that, during mechanical ventilation, surfactant-depleted low-aeration lung regions present increased regional (18)F-FDG uptake suggestive of in vivo increased regional metabolic activity and inflammation. Sheep underwent unilateral saline lung lavage and were ventilated supine for 4 h (positive end-expiratory pressure = 10 cmH(2)O, tidal volume adjusted to plateau pressure = 30 cmH(2)O). We used PET scans of injected (13)N-nitrogen to compute regional perfusion and ventilation and injected (18)F-FDG to calculate (18)F-FDG uptake rate. Regional aeration was quantified with transmission scans. Whole lung (18)F-FDG uptake was approximately two times higher in lavaged than in nonlavaged lungs (2.9 ± 0.6 vs. 1.5 ± 0.3 10(-3)/min; P < 0.05). The increased (18)F-FDG uptake was topographically heterogeneous and highest in dependent low-aeration regions (gas fraction 10-50%, P < 0.001), even after correction for lung density and wet-to-dry lung ratios. (18)F-FDG uptake in low-aeration regions of lavaged lungs was higher than that in low-aeration regions of nonlavaged lungs (P < 0.05). This occurred despite lower perfusion and ventilation to dependent regions in lavaged than nonlavaged lungs (P < 0.001). In contrast, (18)F-FDG uptake in normally aerated regions was low and similar between lungs. Surfactant depletion produces increased and heterogeneously distributed pulmonary (18)F-FDG uptake after 4 h of supine mechanical ventilation. Metabolic activity is highest in poorly aerated dependent regions, suggesting local increased inflammation.

  6. Social and practical representations in pneumonia associated to ventilation mechanics

    Directory of Open Access Journals (Sweden)

    Giovane Mendieta I

    2009-05-01

    Full Text Available Objective: To identify the practice and social representations of the respiratory therapists, on the strategies of prevention of pneumonia associated to mechanical ventilation, of the unit intensive care of the Kennedy Hospital. Methodology:Qualitative inquiry, descriptive and explanatory character, the population, respiratorys therapist of the unit’s intensives cares, with a sample of captive type for convenience, conformed by seventeen respiratorys therapists who were applied a semistructured interview, applying the content analysis technique for their study. Results: Practices and social representations, are given around the patient, and therefore avoid prolonged mechanical ventilation, the suction procedure should be carried out by means of aseptic technique, on the other and, the strict execution of handling protocols of airway; as long as it should be norm for the whole personnel, hand washing. Conclusions:it is observed the strategies of prevention are influenced by the theoretical references, however, these actors don’t know the full prevention strategies, likewise the represented practices are related with the prevention through asepsis transmission of pathogens, and has an effect on the construction of social representations and therefore the knowledge of new practices will change the structure of representation.

  7. Critical Pertussis in a Young Infant Requiring Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    Heda Melinda Nataprawira

    2013-01-01

    Full Text Available Pertussis may likely be misdiagnosed in its initial or catarrhal phase as a common respiratory infection. The earlier diagnosis of pertussis really depends on the capability of the medical professional especially in the first line public health services. The lack of awareness in diagnosis of severe pertussis as one of the causes of severe respiratory problems may likely misdiagnose pertussis as respiratory failure or even septic shock. In fact, pertussis may manifest as a critical pertussis which can be fatal due to the respiratory failure that require pediatric intensive care unit using mechanical ventilation. We reported a confirmed pertussis case of a 7-weeks-old female infant referred to our tertiary hospital with gasping leading to respiratory failure and septic shock requiring mechanical ventilation, aggressive fluid therapy, and antibiotics. Pertussis was diagnosed late during the course of illness when the patient was hospitalized. Improvement was noted after administering macrolide which gave a good response. Bordetella pertussis isolation from Bordet-Gengou media culture yielded positive result.

  8. A control system for mechanical ventilation of passive and active subjects.

    Science.gov (United States)

    Tehrani, Fleur T

    2013-06-01

    Synchronization of spontaneous breathing with breaths supplied by the ventilator is essential for providing optimal ventilation to patients on mechanical ventilation. Some ventilation techniques such as Adaptive Support Ventilation (ASV), Proportional Assist Ventilation (PAV), and Neurally Adjusted Ventilatory Assist (NAVA) are designed to address this problem. In PAV, the pressure support is proportional to the patient's ongoing effort during inspiration. However, there is no guarantee that the patient receives adequate ventilation. The system described in this article is designed to automatically control the support level in PAV to guarantee delivery of patient's required ventilation. This system can also be used to control the PAV support level based on the patient's work of breathing. This technique further incorporates some of the features of ASV to deliver mandatory breaths for passive subjects. The system has been tested by using computer simulations and the controller has been implemented by using a prototype.

  9. Changes in respiratory and circulatory functions during sequential invasive-noninvasive mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    商鸣宇; 王辰; 代华平; 杨媛华; 姜超美

    2003-01-01

    Objective To investigate the changes in respiratory and circulatory functions in chronic obstructive pulmonary disease (COPD) patients during sequential invasive-noninvasive mechanical ventilation therapy, and evaluate the effects of this new technique.Methods Twelve COPD patients with type Ⅱ respiratory failure due to severe pulmonary infection were ventilated through an endotracheal tube. When the pulmonary infection control window (PIC-Window) occurred, the patients were extubated and were ventilated with a facial mask using pressure support ventilation combined with positive end-expiratory pressure. The parameters of hemodynamics, oxygen dynamics, and esophageal pressure were measured at the PIC-Window during invasive mechanical ventilation, one hour after oxygen therapy via a naso-tube, and three hours after non-invasive mechanical ventilation. Results The variation in esophageal pressure was 20.0±6 cmH2O during naso-tube oxygen therapy, and this variation was higher than that during non-invasive mechanical ventilation (10±6 cmH2O, P0.05).Conclusions The respiratory and circulatory functions of COPD patients remained stable during sequential invasive-noninvasive mechanical ventilation therapy using PIC-Window as a switch point for early extubation. The COPD patients can tolerated the transition from invasive mechanical ventilation to noninvasive mechanical ventilation.

  10. Indoor Environmental Quality in Mechanically Ventilated, Energy-Efficient Buildings vs. Conventional Buildings.

    Science.gov (United States)

    Wallner, Peter; Munoz, Ute; Tappler, Peter; Wanka, Anna; Kundi, Michael; Shelton, Janie F; Hutter, Hans-Peter

    2015-11-06

    Energy-efficient buildings need mechanical ventilation. However, there are concerns that inadequate mechanical ventilation may lead to impaired indoor air quality. Using a semi-experimental field study, we investigated if exposure of occupants of two types of buildings (mechanical vs. natural ventilation) differs with regard to indoor air pollutants and climate factors. We investigated living and bedrooms in 123 buildings (62 highly energy-efficient and 61 conventional buildings) built in the years 2010 to 2012 in Austria (mainly Vienna and Lower Austria). Measurements of indoor parameters (climate, chemical pollutants and biological contaminants) were conducted twice. In total, more than 3000 measurements were performed. Almost all indoor air quality and room climate parameters showed significantly better results in mechanically ventilated homes compared to those relying on ventilation from open windows and/or doors. This study does not support the hypothesis that occupants in mechanically ventilated low energy houses are exposed to lower indoor air quality.

  11. Indoor Environmental Quality in Mechanically Ventilated, Energy-Efficient Buildings vs. Conventional Buildings

    Directory of Open Access Journals (Sweden)

    Peter Wallner

    2015-11-01

    Full Text Available Energy-efficient buildings need mechanical ventilation. However, there are concerns that inadequate mechanical ventilation may lead to impaired indoor air quality. Using a semi-experimental field study, we investigated if exposure of occupants of two types of buildings (mechanical vs. natural ventilation differs with regard to indoor air pollutants and climate factors. We investigated living and bedrooms in 123 buildings (62 highly energy-efficient and 61 conventional buildings built in the years 2010 to 2012 in Austria (mainly Vienna and Lower Austria. Measurements of indoor parameters (climate, chemical pollutants and biological contaminants were conducted twice. In total, more than 3000 measurements were performed. Almost all indoor air quality and room climate parameters showed significantly better results in mechanically ventilated homes compared to those relying on ventilation from open windows and/or doors. This study does not support the hypothesis that occupants in mechanically ventilated low energy houses are exposed to lower indoor air quality.

  12. 小潮气量和传统潮气量机械通气治疗小儿重症肺炎的疗效对比分析%Comparison of the effects of low and conventional tidal volume mechanical ventilation on the treatment of children with severe pneumonia

    Institute of Scientific and Technical Information of China (English)

    李细林; 顿浩; 孙凯; 江华

    2016-01-01

    Objective: To analyse the effects of low and conventional tidal volume mechanical ventilation on the treatment of children with severe pneumonia.Methods: 100 cases of children with severe pneumonia from June 2013 to June 2015 in our hospital were randomly divided into control group and observation group, each of 50 cases. hTe control group children with traditional tidal volume, tidal volume of 10~12 mL/kg; the observation group children using low tidal volume, tidal volume of 6~8 mL/kg, clinical parameters of two groups during treatmentwere analyzed.Results: hTe mechanical ventilation of the observation group was signiifcantly more than that of the control group (t=11.0770, P=0.0000), the mortality rate of observation group was signiifcantly higher than that of the control group (χ2=5.4825,P=0.0192). In the course of treatment, children mean airway pressure (Paw), fraction of inspiration O2 (FiO2), positive end expiratory pressure (PEEP), peak inflating pressure (PIP) and other clinical indexes of two groups had no significant difference (P>0.05), recurrent respiratory tract infections survival rate between the two groups had no significant difference (χ2=0.0624,P=0.8028). Conclusion: For children with severe pneumonia mechanical ventilation, the effect of traditional tidal volume shows better than low tidal volume.%目的:对比分析小潮气量和传统潮气量机械通气治疗小儿重症肺炎的疗效。方法:对2013年6月至2015年6月在我院进行接治的100例小儿重症肺炎进行研究,将患儿随机分为对照组和观察组,各50例,对照组的患儿采用传统潮气量,潮气量为10~12 mL/kg;观察组的患儿采用小潮气量,潮气量为6~8 mL/kg,对治疗过程中两组患儿临床参数的变化进行对比分析。结果:观察组患儿的机械通气时间明显多于对照组(t=11.0770,P=0.0000),观察组患儿的病死率明显高于对照组(χ2=5.4825,P=0.0192),治疗过程中,两组患儿的

  13. Exercise oscillatory ventilation:Mechanisms and prognostic significance

    Institute of Scientific and Technical Information of China (English)

    Bishnu P Dhakal; Gregory D Lewis

    2016-01-01

    Alteration in breathing patterns characterized by cyclic variation of ventilation during rest and during exercise has been recognized in patients with advanced heart failure(HF) for nearly two centuries. Periodic breathing(PB) during exercise is known as exercise oscillatory ventilation(EOV) and is characterized by the periods of hyperpnea and hypopnea without interposed apnea. EOV is a non-invasive parameter detected during submaximal cardiopulmonary exercise testing. Presence of EOV during exercise in HF patients indicates significant impairment in resting and exercise hemodynamic parameters. EOV is also an independent risk factor for poor prognosis in HF patients both with reduced and preserved ejection fraction irrespective of other gas exchange variables. Circulatory delay, increased chemosensitivity, pulmonary congestion and increased ergoreflex signaling have been proposed as the mechanisms underlying the generation of EOV in HF patients. There is no proven treatment of EOV but its reversal has been noted with phosphodiesterase inhibitors, exercise training and acetazolamide in relatively small studies. In this review, we discuss the mechanistic basis of PB during exercise and the clinical implications of recognizing PB patterns in patients with HF.

  14. Recruitment manoeuvres for adults with acute respiratory distress syndrome receiving mechanical ventilation.

    Science.gov (United States)

    Hodgson, Carol; Goligher, Ewan C; Young, Meredith E; Keating, Jennifer L; Holland, Anne E; Romero, Lorena; Bradley, Scott J; Tuxen, David

    2016-11-17

    Recruitment manoeuvres involve transient elevations in airway pressure applied during mechanical ventilation to open ('recruit') collapsed lung units and increase the number of alveoli participating in tidal ventilation. Recruitment manoeuvres are often used to treat patients in intensive care who have acute respiratory distress syndrome (ARDS), but the effect of this treatment on clinical outcomes has not been well established. This systematic review is an update of a Cochrane review originally published in 2009. Our primary objective was to determine the effects of recruitment manoeuvres on mortality in adults with acute respiratory distress syndrome.Our secondary objective was to determine, in the same population, the effects of recruitment manoeuvres on oxygenation and adverse events (e.g. rate of barotrauma). For this updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (OVID), Embase (OVID), the Cumulative Index to Nursing and Allied Health Literature (CINAHL, EBSCO), Latin American and Caribbean Health Sciences (LILACS) and the International Standard Randomized Controlled Trial Number (ISRCTN) registry from inception to August 2016. We included randomized controlled trials (RCTs) of adults who were mechanically ventilated that compared recruitment manoeuvres versus standard care for patients given a diagnosis of ARDS. Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information. Ten trials met the inclusion criteria for this review (n = 1658 participants). We found five trials to be at low risk of bias and five to be at moderate risk of bias. Six of the trials included recruitment manoeuvres as part of an open lung ventilation strategy that was different from control ventilation in aspects other than the recruitment manoeuvre (such as mode of ventilation, higher positive end-expiratory pressure (PEEP) titration and lower tidal volume or plateau

  15. Comparison of pneumotachography and anemometery for flow measurement during mechanical ventilation with volatile anesthetics.

    Science.gov (United States)

    Mondoñedo, Jarred R; Herrmann, Jacob; McNeil, John S; Kaczka, David W

    2016-11-14

    Volatile anesthetics alter the physical properties of inhaled gases, such as density and viscosity. We hypothesized that the use of these agents during mechanical ventilation would yield systematic biases in estimates of flow ([Formula: see text]) and tidal volume (V T) for two commonly used flowmeters: the pneumotachograph (PNT), which measures a differential pressure across a calibrated resistive element, and the hot-wire anemometer (HWA), which operates based on convective heat transfer from a current-carrying wire to a flowing gas. We measured [Formula: see text] during ventilation of a spring-loaded mechanical test lung, using both the PNT and HWA placed in series at the airway opening. Delivered V T was estimated from the numerically-integrated [Formula: see text]. Measurements were acquired under baseline conditions with room air, and during ventilation with increasing concentrations of isoflurane, sevoflurane, and desflurane. We also evaluated a simple compensation technique for HWA flow, which accounted for changes in gas mixture density. We found that discrepancies in estimated V T between the PNT and HWA occurred during ventilation with isoflurane (6.3 ± 3.0%), sevoflurane (10.0 ± 7.3%), and desflurane (25.8 ± 17.2%) compared to baseline conditions. The magnitude of these discrepancies increased with anesthetic concentration. A simple compensation factor based on density reduced observed differences between the flowmeters, regardless of the anesthetic or concentration. These data indicate that the choice and concentration of anesthetic agents are primary factors for differences in estimated V T between the PNT and HWA. Such discrepancies may be compensated by accounting for alterations in gas density.

  16. Development of mechanical ventilation system with low energy consumption for renovation of buildings

    DEFF Research Database (Denmark)

    Terkildsen, Søren

    the performance of mechanical ventilation systems. The power consumption of mechanical ventilation depends on the flow rate, fan efficiency and pressure loss in the system. This thesis examines the options and develops a concept and components for the design of low-pressure mechanical ventilation. The hypothesis....... Paper I introduces the concept and its performance is evaluated through simulations of a system designed for a test-case building. All the components were designed to minimize pressure losses and therefore the fan power needed to operate the system. The total pressure loss was 30-75 Pa depending......, including ventilation, therefore now represent a larger part of the total energy consumption. Mechanical ventilation has been the most widely used principle of ventilation over the last 50 years, but the conventional system design needs revising to meet future energy requirements. The increase in the use...

  17. Effects of a 1:1 inspiratory to expiratory ratio on respiratory mechanics and oxygenation during one-lung ventilation in the lateral decubitus position.

    Science.gov (United States)

    Kim, S H; Choi, Y S; Lee, J G; Park, I H; Oh, Y J

    2012-11-01

    Prolonged inspiratory to expiratory (I:E) ratio ventilation may have both positive and negative effects on respiratory mechanics and oxygenation during one-lung ventilation (OLV), but definitive information is currently lacking. We therefore compared the effects of volume-controlled ventilation with I:E ratios of 1:1 and 1:2 on respiratory mechanics and oxygenation during OLV. Fifty-six patients undergoing thoracoscopic lobectomy were randomly assigned volume-controlled ventilation with an I:E ratio of 1:1 (group 1:1, n=28) or 1:2 (group 1:2, n=28) during OLV. Arterial and central venous blood gas analyses and respiratory variables were recorded 15 minutes into two-lung ventilation, at 30 and 60 minutes during OLV, and 15 minutes after two-lung ventilation was re-initiated. Peak and plateau airway pressures in cmH2O [standard deviation] during OLV were significantly lower in group 1:1 than in group 1:2 (P ventilation with an I:E ratio of 1:1 reduced peak and plateau airway pressures improved dynamic compliance and efficiency of alveolar ventilation, but it did not improve arterial oxygenation in a substantial manner. Furthermore, the associated increase in mean airway pressure might have reduced cardiac output, resulting in a lower central venous oxygen saturation.

  18. Assessing the influence of mechanical ventilation on blood gases and blood pressure in rattlesnakes

    DEFF Research Database (Denmark)

    Bertelsen, Mads F.; Buchanan, Rasmus; Jensen, Heidi M.

    2015-01-01

    OBJECTIVE: To characterize the impact of mechanical positive pressure ventilation on heart rate (HR), arterial blood pressure, blood gases, lactate, glucose, sodium, potassium and calcium concentrations in rattlesnakes during anesthesia and the subsequent recovery period. STUDY DESIGN: Prospective...... ventilation at a tidal volume of 30 mL kg(-1) at 1 breath every 90 seconds, 5 breaths minute(-1) , or 15 breaths minute(-1) . Arterial blood was collected from indwelling catheters at 30, 40, and 60 minutes and 2, 6, and 24 hours following induction of anesthesia and analyzed for pH, PaO2 , PaCO2...... , and selected variables. Mean arterial blood pressure (MAP) and HR were recorded at 30, 40, 60 minutes and 24 hours. RESULTS: Spontaneous ventilation and 1 breath every 90 seconds resulted in a mild hypercapnia (PaCO2 22.4 ± 4.3 mmHg [3.0 ± 0.6 kPa] and 24.5 ± 1.6 mmHg [3.3 ± 0.2 kPa], respectively), 5 breaths...

  19. Driving pressure during assisted mechanical ventilation: Is it controlled by patient brain?

    Science.gov (United States)

    Georgopoulos, Dimitris; Xirouchaki, Nectaria; Tzanakis, Nikolaos; Younes, Magdy

    2016-07-01

    Tidal volume (VT) is the controlled variable during passive mechanical ventilation (CMV) in order to avoid ventilator-induced-lung-injury. However, recent data indicate that the driving pressure [ΔP; VT to respiratory system compliance (Crs) ratio] is the parameter that best stratifies the risk of death. In order to study which variable (VT or ΔP) is controlled by critically ill patients, 108 previously studied patients were assigned to receive PAV+ (a mode that estimates Crs and permits the patients to select their own breathing pattern) after CMV, were re-analyzed. When patients were switched from CMV to PAV+ they controlled ΔP without constraining VT to narrow limits. VT was increased when the resumption of spontaneous breathing was associated with an increase in Crs. When ΔP was high during CMV, the patients (n=12) decreased it in 58 out of 67 measurements. We conclude that critically ill patients control the driving pressure by sizing the tidal volume to individual respiratory system compliance using appropriate feedback mechanisms aimed at limiting the degree of lung stress.

  20. Mechanical ventilation with heat recovery in arctic climate

    DEFF Research Database (Denmark)

    Kragh, Jesper; Svendsen, Svend

    2005-01-01

    Mechanical ventilations systems with highly effective heat recovery units in arctic climate have problems with condensing water from the extracted humid indoor air. If the condensing water freezes to ice in the heat recovery unit, the airflow rate will quickly diminish due to the increasing...... pressure drop. Preheating the inlet air (outdoor air) to a temperature just above 0ºC is typically used to solve the problem. To minimize the energy cost, a more efficient solution to the problem is therefore desirable. In this project a new design of a heat recovery unit has been developed to the low......-energy house in Sisimiut, which is capable of continuously defrosting itself. The disadvantage of the unit is that it is quite big compared with other units. In this paper the new heat recovery unit is described and laboratory measurements are presented showing that the unit is capable of continuously...

  1. Quantitative investigation of alveolar structures with OCT using total liquid ventilation during mechanical ventilation

    Science.gov (United States)

    Schnabel, Christian; Gaertner, Maria; Meissner, Sven; Koch, Edmund

    2012-02-01

    To develop new treatment possibilities for patients with severe lung diseases it is crucial to understand the lung function on an alveolar level. Optical coherence tomography (OCT) in combination with intravital microscopy (IVM) are used for imaging subpleural alveoli in animal models to gain information about dynamic and morphological changes of lung tissue during mechanical ventilation. The image content suitable for further analysis is influenced by image artifacts caused by scattering, refraction, reflection, and absorbance. Because the refractive index varies with each air-tissue interface in lung tissue, these effects decrease OCT image quality exceedingly. The quality of OCT images can be increased when the refractive index inside the alveoli is matched to the one of tissue via liquid-filling. Thereby, scattering loss can be decreased and higher penetration depth and tissue contrast can be achieved. To use the advantages of liquid-filling for in vivo imaging of small rodent lungs, a suitable breathing fluid (perfluorodecalin) and a special liquid respirator are necessary. Here we show the effect of liquid-filling on OCT and IVM image quality of subpleural alveoli in a mouse model.

  2. Effects of mechanical ventilation with lower tidal volume and positive end-expiratory pressure on pulmonary function during laparoscopic surgery in patients with chronic obstructive pulmonary disease%低潮气量联合呼气末正压通气对慢性阻塞性肺疾病患者腹腔镜手术时肺功能的影响

    Institute of Scientific and Technical Information of China (English)

    陈志远; 吴健华; 王玉珍; 李岩; 许小婷

    2013-01-01

    Objective To investigate the effects of mechanicl ventilation with lower tidal volume and positive end-expiratory pressure (PEEP) on pulmonary function during laparoscopic surgery in patients with chronic obstructive pulmonary disease (COPD).Methods Forty patients with COPD,aged 60-82 yr,with body mass index of 16-29 kg/m2,undergoing elective laparoscopic surgery,were randomly divided into 2 groups (n =20 each) using a random number table:conventional ventilation group (group Ⅰ) and mechanical ventilation with lower tidal volume and PEEP group (group Ⅱ).Anesthesia was induced with midazolam,sufentanil,cisatracurium and propofol and maintained with iv infusion of propofol,cisawacurium and remifentanil.The patients were endotracheally ventilated and mechanically ventilated.In group Ⅰ,fresh gas flow was set at 2 L/min,VT at 10 ml/kg,and I∶E at 1∶2 during ventilation.In group Ⅱ,fresh gas flow was set at 2 L/min,VT at 6 ml/kg,I∶E at 1∶2 and PEEP at 6 cm H2O during ventilation.PErCO2 was maintained at 35-45 mm Hg in both groups.Airway peak pressure (Pp~),airway plateau pressure (Pplat),airway resistance (Raw) and dynamic lung compliance (Cdyn) were measured at 5 min after intubation (T1),45 min of pneumoperitoneum (T2),and 15 min after the end of pneumoperitoneum (T3).Arterial blood samples were obtained at T1,T2 and T3 for blood gas analysis.Alveolar-arterial oxygen gradiant (A-aDO2),oxygenation index (PaO2/FiO2),respiratory index (RI) and physiologic dead space fraction (VD/VT) were calculated.The extubation time and development of complications were recorded within 48 h after operation.Results Compared with group Ⅰ,Ppeak and Plat at T2 and Raw at T1,2 were significantly decreased,Cdyn at T2 and PaO2/FiO2 at T1-3 were significantly increased,RI,VD/VT and A-aDO2 were significantly decreased at T1-3,and the incidence of hyoxemia,atelectasis and rales was decreased within 48 h after operation in group Ⅱ (P < 0.05).There was no significant difference

  3. Evaluation of the user interface simplicity in the modern generation of mechanical ventilators.

    Science.gov (United States)

    Uzawa, Yoshihiro; Yamada, Yoshitsugu; Suzukawa, Masayuki

    2008-03-01

    We designed this study to evaluate the simplicity of the user interface in modern-generation mechanical ventilators. We hypothesized that different designs in the user interface could result in different rates of operational failures. A laboratory in a tertiary teaching hospital. Crossover design. Twenty-one medical resident physicians who did not possess operating experience with any of the selected ventilators. Four modern mechanical ventilators were selected: Dräger Evita XL, Maquet Servo-i, Newport e500, and Puritan Bennett 840. Each subject was requested to perform 8 tasks on each ventilator. Two objective variables (the number of successfully completed tasks without operational failures and the operational time) and the overall subjective rating of the ease of use, measured with a 100-mm visual analog scale were recorded. The total percentage of operational failures made for all subjects, for all tasks, was 23%. There were significant differences in the rates of operational failures and operational time among the 4 ventilators. Subjects made more operational failures in setting up the ventilators and in making ventilator-setting changes than in reacting to alarms. The subjective feeling of the ease of use was also significantly different among the ventilators. The design of the user interface is relevant to the occurrence of operational failures. Our data indicate that ventilator designers could optimize the user-interface design to reduce the operational failures; therefore, basic user interface should be standardized among the clinically used mechanical ventilators.

  4. Technology for noninvasive mechanical ventilation: looking into the black box

    Directory of Open Access Journals (Sweden)

    Ramon Farré

    2016-03-01

    Full Text Available Current devices for providing noninvasive respiratory support contain sensors and built-in intelligence for automatically modifying ventilation according to the patient's needs. These devices, including automatic continuous positive airway pressure devices and noninvasive ventilators, are technologically complex and offer a considerable number of different modes of ventilation and setting options, the details of which are sometimes difficult to capture by the user. Therefore, better predicting and interpreting the actual performance of these ventilation devices in clinical application requires understanding their functioning principles and assessing their performance under well controlled bench test conditions with simulated patients. This concise review presents an updated perspective of the theoretical basis of intelligent continuous positive airway pressure and noninvasive ventilation devices, and of the tools available for assessing how these devices respond under specific ventilation phenotypes in patients requiring breathing support.

  5. Respiratory mechanics during high-frequency oscillatory ventilation: a physical model and preterm infant study.

    Science.gov (United States)

    Singh, Rachana; Courtney, Sherry E; Weisner, Michael D; Habib, Robert H

    2012-04-01

    Accurate mechanics measurements during high-frequency oscillatory ventilation (HFOV) facilitate optimizing ventilator support settings. Yet, these are influenced substantially by endotracheal tube (ETT) contributions, which may dominate when leaks around uncuffed ETT are present. We hypothesized that 1) the effective removal of ETT leaks may be confirmed via direct comparison of measured vs. model-predicted mean intratracheal pressure [mPtr (meas) vs. mPtr (pred)], and 2) reproducible respiratory system resistance (Rrs) and compliance (Crs) may be derived from no-leak oscillatory Ptr and proximal flow. With the use of ETT test-lung models, proximal airway opening (Pao) and distal (Ptr) pressures and flows were measured during slow-cuff inflations until leaks are removed. These were repeated for combinations of HFOV settings [frequency, mean airway pressure (Paw), oscillation amplitudes (ΔP), and inspiratory time (%t(I))] and varying test-lung Crs. Results showed that leaks around the ETT will 1) systematically reduce the effective distending pressures and lung-delivered oscillatory volumes, and 2) derived mechanical properties are increasingly nonphysiologic as leaks worsen. Mean pressures were systematically reduced along the ventilator circuit and ETT (Paw > Pao > Ptr), even for no-leak conditions. ETT size-specific regression models were then derived for predicting mPtr based on mean Pao (mPao), ΔP, %t(I), and frequency. Next, in 10 of 11 studied preterm infants (0.77 ± 0.24 kg), no-to-minimal leak was confirmed based on excellent agreement between mPtr (meas) and mPtr (pred), and consequently, their oscillatory respiratory mechanics were evaluated. Infant resistance at the proximal ETT (R(ETT); resistance airway opening = R(ETT) + Rrs; P mechanical properties that can objectively guide ventilatory management of HFOV-treated preterm infants.

  6. Infants with severe respiratory syncytial virus needed less ventilator time with nasal continuous airways pressure then invasive mechanical ventilation

    NARCIS (Netherlands)

    Borckink, Ilse; Essouri, Sandrine; Laurent, Marie; Albers, Marcel J. I. J.; Burgerhof, Johannes G. M.; Tissieres, Pierre; Kneyber, Martin C. J.

    2014-01-01

    AIM: Nasal continuous positive airway pressure (NCPAP) has been proposed as an early first-line support for infants with severe respiratory syncytial virus (RSV) infection. We hypothesised that infants <6 months with severe RSV would require shorter ventilator support on NCPAP than invasive mechanic

  7. Stroke volume variation does not predict fluid responsiveness in patients with septic shock on pressure support ventilation

    DEFF Research Database (Denmark)

    Perner, A; Faber, T

    2006-01-01

    Stroke volume variation (SVV)--as measured by the pulse contour cardiac output (PiCCO) system--predicts the cardiac output response to a fluid challenge in patients on controlled ventilation. Whether this applies to patients on pressure support ventilation is unknown....

  8. Model-based advice for mechanical ventilation: From research (INVENT) to product (Beacon Caresystem).

    Science.gov (United States)

    Rees, Stephen E; Karbing, Dan S

    2015-01-01

    This paper describes the structure and functionality of a physiological model-based system for providing advice on the settings of mechanical ventilation. Use of the system is presented with examples of patients on support and control modes of mechanical ventilation.

  9. High-Frequency Percussive Ventilation: Pneumotachograph Validation and Tidal Volume Analysis

    Science.gov (United States)

    2010-06-01

    Meredith Pride for their invaluable research efforts. Table 3. Mean Difference in High-Frequency VT* Relative to Test- Lung VT† Difference in High...respiratory gas on pneumotachographic measurement of ventilation in newborn infants. Biomed Tech 1994;39(4):85-92. 15. Jackson AC, Vinegar A. A technique...for measuring frequency re- sponse of pressure, volume, and flow transducers. J Appl Physiol 1979;47(2):462-467. 16. Finucane KE, Egan BA, Dawson SV

  10. The comparison of manual and LabVIEW-based fuzzy control on mechanical ventilation.

    Science.gov (United States)

    Guler, Hasan; Ata, Fikret

    2014-09-01

    The aim of this article is to develop a knowledge-based therapy for management of rats with respiratory distress. A mechanical ventilator was designed to achieve this aim. The designed ventilator is called an intelligent mechanical ventilator since fuzzy logic was used to control the pneumatic equipment according to the rat's status. LabVIEW software was used to control all equipments in the ventilator prototype and to monitor respiratory variables in the experiment. The designed ventilator can be controlled both manually and by fuzzy logic. Eight female Wistar-Albino rats were used to test the designed ventilator and to show the effectiveness of fuzzy control over manual control on pressure control ventilation mode. The anesthetized rats were first ventilated for 20 min manually. After that time, they were ventilated for 20 min by fuzzy logic. Student's t-test for p < 0.05 was applied to the measured minimum, maximum and mean peak inspiration pressures to analyze the obtained results. The results show that there is no statistical difference in the rat's lung parameters before and after the experiments. It can be said that the designed ventilator and developed knowledge-based therapy support artificial respiration of living things successfully.

  11. Performance of low pressure mechanical ventilation concept with diffuse ceiling inlet for renovation of school classrooms

    DEFF Research Database (Denmark)

    Terkildsen, Søren; Svendsen, Svend

    In a great portion of Danish primary schools the mechanical ventilation systems is outdated or simply rely on opening of windows to ventilate the classrooms. This leads to high energy consumption for fans and/or ventilation heat losses and poor indoor environment, as the ventilation systems cannot...... provide a sufficient ventilation rate. A recent study with 750 Danish classrooms show that 56 % had CO2-concentrations over a 1000 ppm, which is the recommended limit by the Danish working environment authority and this adversely affects the performance and well being of the pupils. This paper describes...... a mechanical ventilation concept to lower energy consumption and improve the indoor environment, developed for refurbishment of school classrooms. The performance of the concept is investigated through computer simulations and measurements of energy consumption and indoor environment. The measurements are made...

  12. Analysis of multiple linear regression algorithms used for respiratory mechanics monitoring during artificial ventilation.

    Science.gov (United States)

    Polak, Adam G

    2011-02-01

    Many patients undergo long-term artificial ventilation and their respiratory system mechanics should be monitored to detect changes in the patient's state and to optimize ventilator settings. In this work the most popular algorithms for tracking variations of respiratory resistance (R(rs)) and elastance (E(rs)) over a ventilatory cycle were analysed in terms of systematic and random errors. Additionally, a new approach was proposed and compared to the previous ones. It takes into account an exact description of flow integration by volume-dependent lung compliance. The results of analyses showed advantages of this new approach and enabled to form several suggestions. Algorithms including R(rs) and E(rs) dependencies on airflow and lung volume can be effectively applied only at low levels of noise present in measurement data, otherwise the use of the simplest model with constant parameters is preferable. Additionally, one should avoid including the resistance dependence on airflow alone, since this considerably destroys the retrieved trace of R(rs). Finally, the estimated cyclic trajectories of R(rs) and E(rs) are more sensitive to noise present in pressure than in the flow signal, and the elastance traces are estimated more accurately than the resistance ones.

  13. TLR2 deficiency aggravates lung injury caused by mechanical ventilation

    NARCIS (Netherlands)

    Kuipers, Maria Theresa; Jongsma, Geartsje; Hegeman, Maria A; Tuip-de Boer, Anita M; Wolthuis, Esther K; Choi, Goda; Bresser, Paul; van der Poll, Tom; Schultz, Marcus J; Wieland, Catharina W

    2014-01-01

    Innate immunity pathways are found to play an important role in ventilator-induced lung injury. We analyzed pulmonary expression of Toll-like receptor 2 (TLR2) in humans and mice and determined the role of TLR2 in the pathogenesis of ventilator-induced lung injury in mice. Toll-like receptor 2 gene

  14. Experimental evaluation of air distribution in mechanically ventilated residential rooms

    DEFF Research Database (Denmark)

    Tomasi, R.; Krajčík, M.; Simone, A.

    2013-01-01

    The effect of low ventilation rates (1 or 0.5 air change per hour) on thermal comfort and ventilation effectiveness was experimentally studied in a simulated residential room equipped with radiant floor heating/cooling and mixing ventilation systems. The tests were performed for various positions...... removal effectiveness (CRE) and local air change index was measured in order to characterize ventilation effectiveness in the occupied zone. Acceptable thermal comfort was found in most experiments; however, air temperature differences higher than 3 °C occurred when floor cooling was combined...... with unconditioned outdoor air supply, i.e. at the supply air temperatures higher than the room air temperature. Moreover, low floor temperatures were needed to maintain the desired reference temperature in the stratified thermal environment. Mainly in cooling conditions the ventilation effectiveness depended...

  15. Non lineal respiratory systems mechanics simulation of acute respiratory distress syndrome during mechanical ventilation.

    Science.gov (United States)

    Madorno, Matias; Rodriguez, Pablo O

    2010-01-01

    Model and simulation of biological systems help to better understand these systems. In ICUs patients often reach a complex situation where supportive maneuvers require special expertise. Among them, mechanical ventilation in patients suffering from acuter respiratory distress syndrome (ARDS) is specially challenging. This work presents a model which can be simulated and use to help in training of physicians and respiratory therapists to analyze the respiratory mechanics in this kind of patients. We validated the model in 2 ARDS patients.

  16. A polynomial model of patient-specific breathing effort during controlled mechanical ventilation.

    Science.gov (United States)

    Redmond, Daniel P; Docherty, Paul D; Yeong Shiong Chiew; Chase, J Geoffrey

    2015-08-01

    Patient breathing efforts occurring during controlled ventilation causes perturbations in pressure data, which cause erroneous parameter estimation in conventional models of respiratory mechanics. A polynomial model of patient effort can be used to capture breath-specific effort and underlying lung condition. An iterative multiple linear regression is used to identify the model in clinical volume controlled data. The polynomial model has lower fitting error and more stable estimates of respiratory elastance and resistance in the presence of patient effort than the conventional single compartment model. However, the polynomial model can converge to poor parameter estimation when patient efforts occur very early in the breath, or for long duration. The model of patient effort can provide clinical benefits by providing accurate respiratory mechanics estimation and monitoring of breath-to-breath patient effort, which can be used by clinicians to guide treatment.

  17. Non-Invasive Mechanic Ventilation Using in Flail Chest, Caused By Blunt Chest Trauma

    Directory of Open Access Journals (Sweden)

    Serdar Onat

    2008-01-01

    Full Text Available A 75-year-old woman admitted our faculty emergency room with shortness of breath, and chest pain after traffic accident’s second hour. She was diagnosed as bilateral multipl rib fractures, left clavicula fracture, and left flail chest by phsical and radiological examinations. She was transfered to Chest Surgery Depatment’s intensive care unit. The patient was undergone non-invasive mask mechanic ventilation support, because of the decreasing of blood oxygen saturation and increasing of arteriel blood partial carbondioxide pressure. The treatment of non-invasive mechanic ventilation was succesfull for ventilation support. With this report, we would like to attentioned that non-invasive mechanic ventilation for blunt chest trauma patients could be used succesfully and could be used instead of endotracheal invasive mechanic ventilation.

  18. Sequential non-invasive mechanical ventilation following short-term invasive mechanical ventilation in COPD induced hypercapnic respiratory failure

    Institute of Scientific and Technical Information of China (English)

    王辰; 商鸣宇; 黄克武; 童朝晖; 孔维民; 姜超美; 代华平; 张洪玉; 翁心植

    2003-01-01

    Objective To estimate the feasibility and the efficacy of early extubation and sequential non-invasive mechanical ventilation (MV) in chronic obstructive pulmonary disease (COPD) with exacerbated hypercapnic respiratory failure.Methods Twenty-two intubated COPD patients with severe hypercapnic respiratory failure due to pulmonary infection (pneumonia or purulent bronchitis) were involved in the study. At the time of pulmonary infection control window (PIC window) appeared, when pulmonary infection had been significantly controlled (resolution of fever and decrease in purulent sputum, radiographic infiltrations, and leukocytosis) after the antibiotic and the comprehensive therapy, the early extubation was conducted and followed by non-invasive MV via facial mask immediately in 11 cases (study group). Other 11 COPD cases with similar clinical characteristics who continuously received invasive MV after PIC window were recruited as control group.Results All patients had similar clinical characteristics and gas exchange before treatment, as well as the initiating time and all indices at the time of the PIC window. For study group and control group, the duration of invasive MV was (7.1±2.9) vs (23.0±14.0) days, respectively, P<0.01. The total duration of ventilatory support was (13±7) vs (23±14) days, respectively, P<0.05. The incidence of ventilator associated pneumonia (VAP) were 0/11 vs 6/11, respectively, P<0.01. The duration of intensive care unit (ICU) stay was (13±7) vs (26±14) days, respectively, P<0.05. Conclusions In COPD patients requiring intubation and MV for pulmonary infection and hypercapnic respiratory failure, early extubation followed by non-invasive MV initiated at the point of PIC window significantly decreases the invasive and total durations of ventilatory support, the risk of VAP, and the duration of ICU stay.

  19. Effects of serum of the rats ventilated with high tidal volume on endothelial cell permeability and therapeutic effects of ulinastatin

    Institute of Scientific and Technical Information of China (English)

    HUO Guo-dong; CAI Shao-xi; CHEN Bo; CHEN Ying-hua

    2006-01-01

    Background With the widespread use of ventilators in treating critically ill patients, the morbidity of ventilator-induced lung injury (VILI) is increasing accordingly. VILI is characterized by a considerable increase in microvascular leakiness and activation of inflammatory processes. In this study we investigated the effects of inflammatory mediators in VILI rat serum on endothelial cytoskeleton and monolayer cellular permeability, as well as the therapeutic effect of ulinastatin, to explore the pathogenesis and the relationship between biotrauma and lung oedema induced by VILI.Methods Thirty healthy male Sprague-Dawley rats were randomly divided into three groups: group A (normal tidal volume ventilation), group B (high tidal volume ventilation) and group C (high tidal volume ventilation plus ulinastatin). The serum of each rat after ventilation was added to endothelial cell line ECV-304 medium for two hours to observe the effects of serum and/or ulinastatin on endothelial fibrous actin and permeability. Results Compared to rats ventilated with normal tidal volume, serum of rats ventilated with high tidal volume caused a striking reorganization of actin cytoskeleton with a weakening of fluorescent intensity at the peripheral filament bands and formation of the long and thick stress fibres in the centre resulting in endothelial contraction and higher permeability. Prior treatment with ulinastatin lessened the above changes significantly. The changes of permeability coefficient of endothelial permeability after group A, B or C rats serum stimulation were (6.95 ±1.66)%, (27.50±7.77)% and (17.71±4.66)% respectively with statistically significant differences (P<0.05)among the three groups.Conclusions The proinflammatory mediators in the serum of the rats given high tidal volume ventilation increases endothelial permeability by reorganizing actin cytoskeleton, and pretreatment with ulinastatin lessens the permeability by inhibiting of proinflammatory mediators.

  20. Effects of manual chest compression and descompression maneuver on lung volumes, capnography and pulse oximetry in patients receiving mechanical ventilation Efeitos da manobra de compressão e descompressão torácica nos volumes pulmonares, capnografia e oximetria de pulso em pacientes submetidos à ventilação mecânica

    Directory of Open Access Journals (Sweden)

    Fabiana Della Via

    2012-10-01

    Full Text Available OBJECTIVES: The aims of this study were to evaluate whether there are changes in lung volumes, capnography, pulse oximetry and hemodynamic parameters associated with manual chest compression-decompression maneuver (MCCD in patients undergoing mechanical ventilation (MV. Method: A prospective study of 65 patients undergoing to MV after 24 hours. All patients received bronchial hygiene maneuvers and after 30 minutes they were submitted to ten repetitions of the MCCD during 10 consecutive respiratory cycles in the right hemithorax and than in the left hemithorax. The data were collected before the application of the maneuver and after 1, 5, 10, 15, 20, 25, 30, 35 and 40 minutes following application of the maneuver. RESULTS: There were statistical significant (pOBJETIVOS: Avaliar a presença de alterações nos volumes pulmonares, oximetria de pulso, capnografia e alterações hemodinâmicas associadas à intervenção da manobra de compressão e descompressão torácica (MCDT nos pacientes submetidos à ventilação mecânica (VM. Método: Tratou-se de um estudo prospectivo em que foram incluídos 65 pacientes em VM há mais de 24 horas. O protocolo consistiu na aplicação de manobras de higiene brônquica e, após 30 minutos, os pacientes eram submetidos a dez repetições da MCDT em dez respirações consecutivas no hemitórax direito e, posteriormente, no hemitórax esquerdo, coletando os dados antes e após a aplicação da manobra nos tempos 1, 5, 10, 15, 20, 25, 30, 35 e 40 minutos. RESULTADOS: Constatou-se aumento significante (p<0,001 do volume corrente inspiratório (pré: 458,2±132,1 ml; pós 1 minuto: 557,3±139,1; pós 40 minutos: 574,4±151, volume minuto corrente (pré: 7,0±2,7 L/min; pós 1 minuto: 8,7±3,3; pós 40 minutos: 8,8±3,8 e oximetria de pulso (pré: 97,4±2,2%; pós 1 minuto: 97,9±1,8; pós 40 minutos: 98,2±1,6; p<0,05. Ocorreu redução no CO2 expirado (pré: 35,1±9,0 mmHg; pós 1 minuto: 31,5±8,2; pós 40

  1. CONTROLLING MECHANICAL VENTILATION IN ARDS WITH FUZZY LOGIC

    Science.gov (United States)

    Nguyen, Binh; Bernstein, David B.; Bates, Jason H.T.

    2014-01-01

    Purpose The current ventilatory care goal for acute respiratory distress syndrome (ARDS), and the only evidence-based approach for managing ARDS, is to ventilate with a tidal volume (VT) of 6 ml/kg predicted body weight (PBW). However, it is not uncommon for some caregivers to feel inclined to deviate from this strategy for one reason or another. To accommodate this inclination in a rationalized manner, we previously developed an algorithm that allows for VT to depart from 6 ml/kg PBW based on physiological criteria. The goal of the present study was to test the feasibility of this algorithm in a small retrospective study. Materials and Methods Current values of peak airway pressure (PAP), positive end-expiratory pressure (PEEP) and arterial oxygen saturation (SaO2) are used in a fuzzy logic algorithm to decide how much VT should differ from 6 ml/kg PBW and how much PEEP should change from its current setting. We retrospectively tested the predictions of the algorithm against 26 cases of decision making in 17 patients with ARDS. Results Differences between algorithm and physician VT decisions were within 2.5 ml/kg PBW except in 1 of 26 cases, and differences between PEEP decisions were within 2.5 cm H2O except in 3 of 26 cases. The algorithm was consistently more conservative than physicians in changing VT, but was slightly less conservative when changing PEEP. Conclusions Within the limits imposed by a small retrospective study, we conclude that our fuzzy logic algorithm makes sensible decisions while at the same time keeping practice close to the current ventilatory care goal. PMID:24721387

  2. Anticipation of distress after discontinuation of mechanical ventilation in the ICU at the end of life

    NARCIS (Netherlands)

    E.J.O. Kompanje (Erwin); B. van der Hoven (Ben); J. Bakker (Jan)

    2008-01-01

    textabstractBackground: A considerable number of patients admitted to the intensive care unit (ICU) die following withdrawal of mechanical ventilation. After discontinuation of ventilation without proper preparation, excessive respiratory secretion is common, resulting in a 'death rattle'. Post-extu

  3. Incidence of Ventilator-Associated Pneumonia in Critically Ill Children Undergoing Mechanical Ventilation in Pediatric Intensive Care Unit

    Directory of Open Access Journals (Sweden)

    Ali Amanati

    2017-07-01

    Full Text Available Background: Among hospital-acquired infections (HAIs in children, ventilator-associated pneumonia (VAP is the most common after blood stream infection (BSI. VAP can prolong length of ventilation and hospitalization, increase mortality rate, and directly change a patient’s outcome in Pediatric Intensive Care Units (PICU. Objectives: The research on VAP in children is limited, especially in Iran; therefore, the identification of VAP incidence and mortality rate will be important for both clinical and epidemiological implications. Materials and Methods: Mechanically ventilated pediatric patients were assessed for development of VAP during hospital course on the basis of clinical, laboratory and imaging criteria. We matched VAP group with control group for assessment of VAP related mortality in the critically ill ventilated children. Results: VAP developed in 22.9% of critically ill children undergoing mechanical ventilation. Early VAP and late VAP were found in 19.3% and 8.4% of VAP cases, respectively. Among the known VAP risk factors that were investigated, immunodeficiency was significantly greater in the VAP group (p = 0.014. No significant differences were found between the two groups regarding use of corticosteroids, antibiotics, PH (potential of hydrogen modifying agents (such as ranitidine or pantoprazole, presence of nasogastric tube and total or partial parenteral nutrition administration. A substantial number of patients in the VAP group had more than four risk factors for development of VAP, compared to those without VAP (p = 0.087. Mortality rate was not statistically different between the VAP and control groups (p = 0.477. Conclusion: VAP is still one of the major causes of mortality in PICUs. It is found that altered immune status is a significant risk factor for acquiring VAP. Also, occurrence of VAP was high in the first week after admission in PICU.

  4. Performance potential of mechanical ventilation systems with minimized pressure loss

    DEFF Research Database (Denmark)

    Terkildsen, Søren; Svendsen, Svend

    2013-01-01

    ventilation systems with minimal pressure loss and minimal energy use. This can provide comfort ventilation and avoid overheating through increased ventilation and night cooling. Based on this concept, a test system was designed for a fictive office building and its performance was documented using building...... simulations that quantify fan power consumption, heating demand and indoor environmental conditions. The system was designed with minimal pressure loss in the duct system and heat exchanger. Also, it uses state-of-the-art components such as electrostatic precipitators, diffuse ceiling inlets and demand......-control ventilation with static pressure set-point reset. All the equipment has been designed to minimize pressure losses and thereby the fan power needed to operate the system. The total pressure loss is 30-75 Pa depending on the operating conditions. The annual average specific fan power is 330 J/m3 of airflow rate...

  5. 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

  6. Evaluation of an Incremental Ventilation Energy Model for Estimating Impacts of Air Sealing and Mechanical Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Logue, Jennifer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Turner, Willliam JN [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-07-01

    Changing the rate of airflow through a home affects the annual thermal conditioning energy. Large-scale changes to airflow rates of the housing stock can significantly alter the energy consumption of the residential energy sector. However, the complexity of existing residential energy models hampers the ability to estimate the impact of policy changes on a state or nationwide level. The Incremental Ventilation Energy (IVE) model developed in this study was designed to combine the output of simple airflow models and a limited set of home characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modelers to use existing databases of home characteristics to determine the impact of policy on ventilation at a population scale. In this report, we describe the IVE model and demonstrate that its estimates of energy change are comparable to the estimates of a wellvalidated, complex residential energy model when applied to homes with limited parameterization. Homes with extensive parameterization would be more accurately characterized by complex residential energy models. The demonstration included a range of home types, climates, and ventilation systems that cover a large fraction of the residential housing sector.

  7. Development of an Outdoor Temperature-Based Control Algorithm for Residential Mechanical Ventilation Control

    Energy Technology Data Exchange (ETDEWEB)

    Less, Brennan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Tang, Yihuan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-06-01

    Smart ventilation systems use controls to ventilate more during those periods that provide either an energy or IAQ advantage (or both) and less during periods that provide a dis advantage. Using detailed building simulations, this study addresses one of the simplest and lowest cost types of smart controllers —outdoor temperature- based control. If the outdoor temperature falls below a certain cut- off, the fan is simply turned off. T he main principle of smart ventilation used in this study is to shift ventilation from time periods with large indoor -outdoor temperature differences, to periods where these differences are smaller, and their energy impacts are expected to be less. Energy and IAQ performance are assessed relative to a base case of a continuously operated ventilation fan sized to comply with ASHRAE 62.2-2013 whole house ventilation requirements. In order to satisfy 62.2-2013, annual pollutant exposure must be equivalent between the temperature controlled and continuous fan cases. This requires ventilation to be greater than 62.2 requirements when the ventilation system operates. This is achieved by increasing the mechanical ventilation system air flow rates.

  8. 呼吸末阻断试验评估感染性休克机械通气患者血容量的临床价值研究%Clinical value of end-expiratory blocking test in assessment of blood volume of septic shock patients undergoing mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    谢晓红; 吴远怡; 符惠雅; 麦叶; 李瑞; 周忠义; 李娜

    2016-01-01

    目的:研究呼气末阻断试验(EEO )在感染性休克机械通气患者容量反应性中的预测效果,以提高容量反应性评估方法、指导患者血容量复苏。方法选取2013年9月-2015年9月医院重症医学科收治的160例感染性休克机械通气患者临床资料进行分析,采用随机对照方法将患者分为对照组和试验组,每组各80例,对照组为对容量负荷试验无反应性,试验组为对容量负荷试验有反应性,患者入院后对其进行EEO ,分析其在感染性休克机械通气患者容量反应性中的预测效果。结果两组患者不同基线下EEO和被动抬腿试验对心率、收缩压、平均血压、舒张压差异无统计学意义;试验组基线1脉压和心脏指数下EEO水平显著高于对照组( P<0.05);试验组基线2脉压和心脏指数水平下PLR显著高于对照组(P<0.05)。结论感染性休克机械通气患者采用EEO、心脏指数以及脉压等指标均能评估患者容量反应性,而EEO评估容量反应性更加可靠。%OBJECTIVE To study the effect of end-expiratory blocking test on prediction of volume responsiveness of the septic shock patients undergoing mechanical ventilation so as to improve the assessment of volume respon-siveness and provide guidance for recovery of blood volume .METHODS The clinical data were collected from 160 septic shock patients who underwent the mechanical ventilation in the critical care medicine department from Sep 2013 to Sep 2015 ,then the enrolled patients were randomly divided into the control group and the experimental group ,with 80 cases in each .The control group was not responsive to the capacity load test ,while the experimen-tal group was responsive to the capacity load test ,the end-expiratory blocking test was carried out for the patients after the admission to the hospital ,and the effect of the end-expiratory blocking test on prediction of volume re-sponsiveness of the

  9. Combined effects of ventilation mode and positive end-expiratory pressure on mechanics, gas exchange and the epithelium in mice with acute lung injury.

    Science.gov (United States)

    Thammanomai, Apiradee; Hamakawa, Hiroshi; Bartolák-Suki, Erzsébet; Suki, Béla

    2013-01-01

    The accepted protocol to ventilate patients with acute lung injury is to use low tidal volume (V(T)) in combination with recruitment maneuvers or positive end-expiratory pressure (PEEP). However, an important aspect of mechanical ventilation has not been considered: the combined effects of PEEP and ventilation modes on the integrity of the epithelium. Additionally, it is implicitly assumed that the best PEEP-V(T) combination also protects the epithelium. We aimed to investigate the effects of ventilation mode and PEEP on respiratory mechanics, peak airway pressures and gas exchange as well as on lung surfactant and epithelial cell integrity in mice with acute lung injury. HCl-injured mice were ventilated at PEEPs of 3 and 6 cmH(2)O with conventional ventilation (CV), CV with intermittent large breaths (CV(LB)) to promote recruitment, and a new mode, variable ventilation, optimized for mice (VV(N)). Mechanics and gas exchange were measured during ventilation and surfactant protein (SP)-B, proSP-B and E-cadherin levels were determined from lavage and lung homogenate. PEEP had a significant effect on mechanics, gas exchange and the epithelium. The higher PEEP reduced lung collapse and improved mechanics and gas exchange but it also down regulated surfactant release and production and increased epithelial cell injury. While CV(LB) was better than CV, VV(N) outperformed CV(LB) in recruitment, reduced epithelial injury and, via a dynamic mechanotransduction, it also triggered increased release and production of surfactant. For long-term outcome, selection of optimal PEEP and ventilation mode may be based on balancing lung physiology with epithelial injury.

  10. Core competency in mechanical ventilation: development of educational objectives using the Delphi technique.

    Science.gov (United States)

    Goligher, Ewan C; Ferguson, Niall D; Kenny, Lisa P

    2012-10-01

    We sought to identify and standardize the core clinical knowledge and skills required to care for patients receiving mechanical ventilation. Prospective survey reaching consensus by the Delphi technique. North American survey conducted anonymously by electronic e-mail. International experts in mechanical ventilation, frontline resident educators, medical education experts, and community intensivists were recruited to participate Fourteen panelists participated (ten content experts, three resident educators, one medical education expert, zero community intensivists). Individual panelists generated a total of 200 educational objectives, of which 109 were duplicates. Of the remaining 91 items, 56 met predefined consensus criteria for inclusion in the final set of educational objectives. The educational objectives spanned a broad range of categories, including respiratory physiology, noninvasive ventilation, lung protective ventilation, weaning, and withholding and withdrawing mechanical ventilation. Agreement among panelists on the items included was high (median proportion supporting item inclusion was 88%, range 70%-100%). There is a consensus that general resident core competency in mechanical ventilation requires a broad range of knowledge application and skill. These educational objectives may help identify and standardize the educational outcomes related to mechanical ventilation that residents should achieve.

  11. Transpulmonary pressure monitoring during mechanical ventilation: a bench-to-bedside review.

    Science.gov (United States)

    Mietto, Cristina; Malbrain, Manu L N G; Chiumello, Davide

    2015-01-01

    Different ventilation strategies have been suggested in the past in patients with acute respiratory distress syndrome (ARDS). Airway pressure monitoring alone is inadequate to assure optimal ventilatory support in ARDS patients. The assessment of transpulmonary pressure (PTP) can help clinicians to tailor mechanical ventilation to the individual patient needs. Transpulmonary pressure monitoring, defined as airway pressure (Paw) minus intrathoracic pressure (ITP), provides essential information about chest wall mechanics and its effects on the respiratory system and lung mechanics. The positioning of an esophageal catheter is required to measure the esophageal pressure (Peso), which is clinically used as a surrogate for ITP or pleural pressure (Ppl), and calculates the transpulmonary pressure. The benefits of such a ventilation approach are avoiding excessive lung stress and individualizing the positive end-expiratory pressure (PEEP) setting. The aim is to prevent over-distention of alveoli and the cyclic recruitment/derecruitment or shear stress of lung parenchyma, mechanisms associated with ventilator-induced lung injury (VILI). Knowledge of the real lung distending pressure, i.e. the transpulmonary pressure, has shown to be useful in both controlled and assisted mechanical ventilation. In the latter ventilator modes, Peso measurement allows one to assess a patient's respiratory effort, patient-ventilator asynchrony, intrinsic PEEP and the calculation of work of breathing. Conditions that have an impact on Peso, such as abdominal hypertension, will also be discussed briefly.

  12. Changes of dipalmitoyl phosphatidyl choline after mechanical ventilation in patients with acute cerebral injury

    Institute of Scientific and Technical Information of China (English)

    HUANG Wei-dong; ZHOU Dao-yang; YANG Yun-mei; XU Zhe-rong; SHEN Mei-ya; SU Wei

    2006-01-01

    Objective: To detect the levels of dipalmitoyl phosphatidyl choline (DPPC) in the sputum of the patients with acute cerebral injury without primary pulmonary injury after mechanical ventilation treatment.Methods: DPPC levels in sputum of 35 patients with acute cerebral injury but without pulmonary injury were detected with high performance liquid chromatography at the beginning of ventilation and 16-20 days, 21-40 days,and 41-60 days after ventilation, respectively.Results: There was no significant difference of the DPPC levels between 16-20 days after ventilation (3.36 ±0.49) and at the beginning of ventilation ( 3.37 ± 0.58 )(P>0.05). The mean levels of DPPC decreased significantly at 21-40 days (2.87 mg/ml ±0.26 mg/ml, P <0.05) and 41-60 days (1.93 mg/ml ±0.21 mg/ml, P <0.01) after ventilation compared with that at the beginning of ventilation. At the same period, the peak inspiratory pressure and the mean pressure of airway increas ed significantly, whereas the static compliance and the partial pressure of oxygen in artery decreased significantly. Among the 25 patients who received ventilation for more than 20days, 8 (32%) had slightly-decreased partial pressure of oxygen in artery compared with that at the beginning of ventilation.Conclusions: Mechanical ventilation can decrease the DPPC levels, decrease the lung compliance and increase the airway pressure, even impair the oxygenation function in patients with acute cerebral injury. Abnormal DPPC is one of the major causes of ventilator-associated lung injury.

  13. Modulating ventilation - low cost VAV for office buildings. [Variable Air Volume]; Modulerende ventilation - low cost VAV til kontor-bygninger. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Hoej Christensen, A.; Olsen, Hans; Drivsholm, C.

    2012-02-15

    The report describes a concept for renovating older existing Constant Air Volume (CAV) ventilation systems to modulating low-cost Variable Air Volume (VAV) systems. The concept is based on the total ventilated area being divided into appropriate indoor climate zones, which can cover from one to several offices with similar climate needs. For this initial climate assessment two relatively ''simple'' tools were developed that can estimate the temperature level in one room from the ventilation airflow, heat loads, etc.: - BSimFast (24-hour mean temperature calculation according to SBI-196, 2000); - BSimLight (Temperature simulation based on Danvak Textbook of Heat and Climate Technology). The concept of 'one room' can also be extended to 'one zone' with appropriate assumptions. However, only one mean room temperature is calculated. The different climate zones were equipped with Halton HFB control unit at the air supply and exhaust side. The project the following feedback options were used: - HFB unit's damper opening degree (0 to 90 degrees); - HFB unit's current flow; - HFB unit's exhaust temperature; and feedback from: - Frequency transformer (fan speed); - The central static duct pressure at the ventilation unit. In the project a control algorithm is developed that ensures a robust control of the entire ventilation system without adverse cyclic variations, based among other things on the exhaust temperature for each climate zone, and with the requirement that at least one throttle valve is always at least 80% open. It turned out that information on the current partial air volumes was necessary in addition to the individual throttle settings. Otherwise, a cyclic variations could not be controlled..Thus, it was the exhaust temperature from individual climate zones that defined the respective volumes of air. The concept was implemented on a complete CAV system and on part of a large CAV system, respectively. (LN)

  14. Effects of high-frequency oscillatory ventilation and conventional mechanical ventilation on oxygen metabolism and tissue perfusion in sheep models of acute respiratory distress syndrome

    Institute of Scientific and Technical Information of China (English)

    Liu Songqiao; Huang Yingzi; Wang Maohua; Chen Qiuhua; Liu Ling; Xie Jianfeng; Tan Li

    2014-01-01

    Background High-frequency oscillatory ventilation (HFOV) allows for small tidal volumes at mean airway pressures (mPaw) above that of conventional mechanical ventilation (CMV),but the effect of HFOV on hemodynamics,oxygen metabolism,and tissue perfusion in acute respiratory distress syndrome (ARDS) remains unclear.We investigated the effects of HFOV and CMV in sheep models with ARDS.Methods After inducing ARDS by repeated lavage,twelve adult sheep were randomly divided into a HFOV or CMV group.After stabilization,standard lung recruitments (40 cmH2O × 40 seconds) were performed.The optimal mPaw or positive end-expiratory pressure was obtained by lung recruitment and decremental positive end-expiratory pressure titration.The animals were then ventilated for 4 hours.The hemodynamics,tissue perfusion (superior mesenteric artery blood flow,pHi,and Pg-aCO2),oxygen metabolism and respiratory mechanics were examined at baseline before saline lavage,in the ARDS model,after model stabilization,and during hourly mechanical ventilation for up to 4 hours.A two-way repeated measures analysis of variance was applied to evaluate differences between the groups.Results The titrated mPaw was higher and the tidal volumes lower in the HFOV group than the positive end-expiratory pressure in the CMV group.There was no significant difference in hemodynamic parameters between the HFOV and CMV groups.There was no difference in the mean alveolar pressure between the two groups.After lung recruitment,both groups showed an improvement in the oxygenation,oxygen delivery,and DO2.Lactate levels increased in both groups after inducing the ARDS model.Compared with the CMV group,the superior mesenteric artery blood flow and pHi were significantly higher in the HFOV group,but the Pg-aCO2 decreased in the HFOV group.Conclusion Compared with CMV,HFOV with optimal mPaw has no significant side effect on hemodynamics or oxygen metabolism,and increases gastric tissue blood perfusion.

  15. Composition and distribution of particulate matter (PM10) in a mechanically ventilated University building

    Science.gov (United States)

    Ali, Mohamed Yasreen Mohamed; Hanafiah, Marlia Mohd; Latif, Mohd Talib

    2016-11-01

    This study analyses the composition and distribution of particulate matter (PM10) in the Biology department building, in UKM. PM10 were collected using SENSIDYNE Gillian GilAir-5 Personal Air Sampling System, a low-volume sampler, whereas the concentration of heavy metals was determined using Inductively coupled plasma-mass spectrometry (ICP-MS). The concentration of PM10 recorded in the mechanically ventilated building ranges from 89 µgm-3 to 910 µgm-3. The composition of the selected heavy metals in PM10 were dominated by zinc, followed by copper, lead and cadmium. It was found that the present of indoor-related particulate matter were originated from the poorly maintained ventilation system, the activity of occupants and typical office equipments such as printers and photocopy machines. The haze event occured during sampling periods was also affected the PM10 concentration in the building. This results can serve as a starting point to assess the potential human health damage using the life cycle impact assessment, expressed in term of disability adjusted life year (DALY).

  16. Gas exchange measurement during pediatric mechanical ventilation--agreement between gas sampling at the airway and the ventilator exhaust.

    Science.gov (United States)

    Smallwood, Craig D; Mehta, Nilesh M

    2013-12-01

    A variety of indirect calorimetry (IC) devices are used for gas exchange measurement and calculation of resting energy expenditure (REE) in the pediatric intensive care unit. The aim of this investigation was to compare oxygen consumption (VO2), carbon dioxide elimination (VCO2), REE and respiratory quotient (RQ) in mechanically ventilated children, obtained by 2 devices using distinct gas sampling methods. Mechanically ventilated children were targeted for IC and gas exchange measurements were recorded for a 30 min period, simultaneously using the E-COVX(®) (gas sampling at the airway) and the Vmax(®) (gas sampling at the humidifier and ventilator exhaust). Steady state gas exchange measurements by the 2 devices were tested for agreement using Spearman correlation and Bland-Altman analysis. Steady state data from both devices were available in 19 tests and were included in the analysis. The correlations coefficients for measurements by the 2 devices were r = 0.903(P < 0.001), 0.955(P < 0.001), 0.944(P < 0.001) and 0.484(P < 0.05) for VO2, VCO2, REE and RQ, respectively. The mean percentage bias (limits of agreement) for VO2, VCO2, REE and RQ values between the two methods (Vmax-E-COVX) was 0.2 (-41.8-42.3), -0.8 (-21.8-20.1), -2.2 (-33.9-29.6) and 1.9 (-21-24.9) respectively. Despite strong correlations and small mean biases for VO2, VCO2 and REE obtained by the Vmax(®) and E-COVX(®), the limits of agreement were beyond the clinically acceptable range. These devices should not be used interchangeably for gas exchange measurements in mechanically ventilated children. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  17. Relationship between airway narrowing, patchy ventilation and lung mechanics in asthmatics.

    Science.gov (United States)

    Tgavalekos, N T; Musch, G; Harris, R S; Vidal Melo, M F; Winkler, T; Schroeder, T; Callahan, R; Lutchen, K R; Venegas, J G

    2007-06-01

    Bronchoconstriction in asthma results in patchy ventilation forming ventilation defects (VDefs). Patchy ventilation is clinically important because it affects obstructive symptoms and impairs both gas exchange and the distribution of inhaled medications. The current study combined functional imaging, oscillatory mechanics and theoretical modelling to test whether the degrees of constriction of airways feeding those units outside VDefs were related to the extent of VDefs in bronchoconstricted asthmatic subjects. Positron emission tomography was used to quantify the regional distribution of ventilation and oscillatory mechanics were measured in asthmatic subjects before and after bronchoconstriction. For each subject, ventilation data was mapped into an anatomically based lung model that was used to evaluate whether airway constriction patterns, consistent with the imaging data, were capable of matching the measured changes in airflow obstruction. The degree and heterogeneity of constriction of the airways feeding alveolar units outside VDefs was similar among the subjects studied despite large inter-subject variability in airflow obstruction and the extent of the ventilation defects. Analysis of the data amongst the subjects showed an inverse relationship between the reduction in mean airway conductance, measured in the breathing frequency range during bronchoconstriction, and the fraction of lung involved in ventilation defects. The current data supports the concept that patchy ventilation is an expression of the integrated system and not just the sum of independent responses of individual airways.

  18. Respiratory mechanics measured by forced oscillations during mechanical ventilation through a tracheal tube.

    Science.gov (United States)

    Scholz, Alexander-Wigbert; Weiler, Norbert; David, Matthias; Markstaller, Klaus

    2011-05-01

    The forced oscillation technique (FOT) allows the measurement of respiratory mechanics in the intensive care setting. The aim of this study was to compare the FOT with a reference method during mechanical ventilation through a tracheal tube. The respiratory impedance spectra were measured by FOT in nine anaesthetized pigs, and resistance and compliance were estimated on the basis of a linear resistance-compliance inertance model. In comparison, resistance and compliance were quantified by the multiple linear regression analysis (LSF) of conventional ventilator waveforms to the equation of motion. The resistance of the sample was found to range from 6 to 21 cmH(2)O s l(-1) and the compliance from 12 to 32 ml cmH(2)O(-1). A Bland-Altman analysis of the resistance resulted in a sufficient agreement (bias -0.4 cmH(2)O s l(-1); standard deviation of differences 1.4 cmH(2)O s l(-1); correlation coefficient 0.93) and test-retest reliability (coefficient of variation of repeated measurements: FOT 2.1%; LSF 1.9%). The compliance, however, was poor in agreement (bias -8 ml cmH(2)O(-1), standard deviation of differences 7 ml cmH(2)O(-1), correlation coefficient 0.74) and repeatability (coefficient of variation: FOT 23%; LSF 1.7%). In conclusion, FOT provides an alternative for monitoring resistance, but not compliance, in tracheally intubated and ventilated subjects.

  19. Mechanical ventilation and sepsis impair protein metabolism in the diaphragm of neonatal pigs

    Science.gov (United States)

    Mechanical ventilation (MV) impairs diaphragmatic function and diminishes the ability to wean from ventilatory support in adult humans. In normal neonatal pigs, animals that are highly anabolic, endotoxin (LPS) infusion induces sepsis, reduces peripheral skeletal muscle protein synthesis rates, but ...

  20. Mechanical ventilation-induced intrathoracic pressure distribution and heart-lung interactions

    NARCIS (Netherlands)

    Lansdorp, Benno; Hofhuizen, C.; van Lavieren, M.A.; van Swieten, H.; Lemson, J.; van Putten, Michel Johannes Antonius Maria; van der Hoeven, J.G.; Pickkers, P.

    2014-01-01

    OBJECTIVE: Mechanical ventilation causes cyclic changes in the heart's preload and afterload, thereby influencing the circulation. However, our understanding of the exact physiology of this cardiopulmonary interaction is limited. We aimed to thoroughly determine airway pressure distribution, how

  1. Mechanical ventilation-induced intrathoracic pressure distribution and heart-lung interactions*

    NARCIS (Netherlands)

    Lansdorp, B.; Hofhuizen, C.M.; Lavieren, M. van; Swieten, H.A. van; Lemson, J.; Putten, M.J.A.M. van; Hoeven, J.G. van der; Pickkers, P.

    2014-01-01

    OBJECTIVE: Mechanical ventilation causes cyclic changes in the heart's preload and afterload, thereby influencing the circulation. However, our understanding of the exact physiology of this cardiopulmonary interaction is limited. We aimed to thoroughly determine airway pressure distribution, how thi

  2. MEASUREMENT OF AMMONIA EMISSIONS FROM MECHANICALLY VENTILATED POULTRY HOUSES USING MULTIPATH TUNABLE DIODE LASER SPECTROSCOPY

    Science.gov (United States)

    Ammonia emissions from mechanically ventilated poultry operations are an important environmental concern. Open Path Tunable Diode Laser Absorption Spectroscopy has emerged as a robust real-time method for gas phase measurement of ammonia concentrations in agricultural settings. ...

  3. Online estimation of respiratory mechanics in non-invasive pressure support ventilation: a bench model study.

    Science.gov (United States)

    Mulqueeny, Qestra; Tassaux, Didier; Vignaux, Laurence; Jolliet, Philippe; Schindhelm, Klaus; Redmond, Stephen; Lovell, Nigel H

    2010-01-01

    An online algorithm for determining respiratory mechanics in patients using non-invasive ventilation (NIV) in pressure support mode was developed and embedded in a ventilator system. Based on multiple linear regression (MLR) of respiratory data, the algorithm was tested on a patient bench model under conditions with and without leak and simulating a variety of mechanics. Bland-Altman analysis indicates reliable measures of compliance across the clinical range of interest (± 11-18% limits of agreement). Resistance measures showed large quantitative errors (30-50%), however, it was still possible to qualitatively distinguish between normal and obstructive resistances. This outcome provides clinically significant information for ventilator titration and patient management.

  4. The Study of Pulmonary Complication of Neonatal Mechanical Ventilation in NICU

    Directory of Open Access Journals (Sweden)

    M.K. Sabzeie

    2016-01-01

    Full Text Available Introduction & Objective: The main indication of mechanical ventilation is in the treatment of neonates with respiratory failure. With the increased use of mechanical ventilation, its complications have increased too. The aim of this study was to evaluate the prevalence of complications and short-term improvement in infants undergoing mechanical ventilation in the neonatal intensive care unit (NICU. Materials & Methods: In this prospective-analytic study, all infants requiring mechanical ventilation and admitted in the neonatal intensive care unit of Fatemiyeh and Be’sat hospitals, have been evaluated for one year (2012. Their data included: neonatal age, sex, gestational age, birth weight, weight at admission, diagnosis, length of hospitalization, disease outcome (improvement-died, need for mechanical ventilation, complications and culture results (blood, endotracheal tube, urine, CSF insert in check list. The data were analysed by SPSS and c2 statistical test. Results: In this study, a total of 114 infants hospitalized in intensive care unit and needed mechanical ventilation was studied of whom 72 were male and 42 were female. The mean of gestational age in the admitted neonates was 32.9 ± 0.85 weeks. The majority of neonates (80.70% were undergoing mechanical ventilation with respiratory distress syndrome (RDS. 67% of neonates were suffering from complications of mechanical ventilation. The prevalent complication was seen in the neonates was narrowing or obstruction of the endotracheal tube (52.63%. 47.37% of infants died and respiratory distress syndrome was the common cause of death in these neonates (46.29%. In our study, there was significant relationship between resuscitation at birth (P=0.002, time required for mechanical ventilation (P=0.0000 and Apgar score (P=0.0000 and complications of mechanical ventilation. Conclusions: The results show that the high prevalence of pulmonary complications is associated with mechanical

  5. Assessment of Sedation and Analgesia in Mechanically Ventilated Patients in Intensive Care Unit

    OpenAIRE

    2008-01-01

    Post traumatic stress resulting from an intensive care unit(ICU) stay may be prevented by adequate level of sedation and analgesia. Aims of the study were reviewing the current practices of sedation and analgesia in our ICU setup and to assess level of sedation and analgesia to know the requirement of sedative and analgesics in mechani-cally ventilated ICU patients. This prospective observational study was conducted on 50 consecutive mechanically ventilated patients in ICU over a period of 6 ...

  6. Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Eric [Building Science Corporation, Westford, MA (United States)

    2014-01-01

    Optimizing whole house mechanical ventilation as part of the Building Ameerica program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this report is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

  7. The effects of positive end-expiratory pressure in alveolar recruitment during mechanical ventilation in pigs

    OpenAIRE

    Madke,Gabriel Ribeiro; Pilla,Eduardo Sperb; Sanchez,Pablo Geraldo; Foernges, Rafael; Grün, Gustavo; Vendrami,Giovani; Fontena,Eduardo; Andrade, Cristiano Feijó; Cardoso, Paulo Francisco Guerreiro

    2008-01-01

    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 P...

  8. Avaliação de parâmetros cardiovasculares, ventilatórios e hemogasométricos de coelhos anestesiados com isofluorano ou sevofluorano e submetidos à ventilação espontânea ou controlada a volume

    OpenAIRE

    Carneiro, R. L.; Nunes,N.; Lopes,P.C.F.; Moro, J.V. [UNESP; Uscategui, R. R. [UNESP; Belmonte, E.a. [UNESP; V.F. Barbosa; Gering, A. P.; Moraes,V.J.; Martins Filho,E.F.; Gomes Júnior, D.c.; Costa Neto, J.M.

    2013-01-01

    The volume-controlled mechanical ventilation and spontaneous ventilation, through haemogasometric, cardiovascular and spirometry variables were evaluated. Twenty-eight rabbits were distributed into two groups: GIVC (isoflurane and volume-controlled ventilation), GIVE (isoflurane and spontaneous ventilation), GSVC (sevoflurane and volume-controlled ventilation) and GSVE (sevoflurane and spontaneous ventilation). Induction was performed by mask with isoflurane (GIVE and GIVC) or sevoflurane (GS...

  9. Invasive mechanical ventilation as a risk factor for acute kidney injury in the critically ill: A systematic review and meta-analysis

    NARCIS (Netherlands)

    J.P. van den Akker (Johannes); M. Egal (Mohamud); J. Groeneveld (Johan)

    2013-01-01

    textabstractIntroduction: Mechanical ventilation (MV) is commonly regarded as a risk factor for acute kidney injury (AKI) in the critically ill. We investigated the strength of this association and whether settings of tidal volume (Vt) and positive end-expiratory pressure (PEEP) affect the risk for

  10. Dynamic and quasi-static lung mechanics system for gas-assisted and liquid-assisted ventilation.

    Science.gov (United States)

    Alvarez, Francisco J; Gastiasoro, Elena; Rey-Santano, M Carmen; Gomez-Solaetxe, Miguel A; Publicover, Nelson G; Larrabe, Juan L

    2009-07-01

    Our aim was to develop a computerized system for real-time monitoring of lung mechanics measurements during both gas and liquid ventilation. System accuracy was demonstrated by calculating regression and percent error of the following parameters compared to standard device: airway pressure difference (Delta P(aw)), respiratory frequency (f(R) ), tidal volume (V(T)), minute ventilation (V'(E)), inspiratory and expiratory maximum flows (V'(ins,max), V'(exp,max)), dynamic lung compliance (C(L,dyn) ), resistance of the respiratory system calculated by method of Mead-Whittenberger (R(rs,MW)) and by equivalence to electrical circuits (R(rs,ele)), work of breathing (W(OB)), and overdistension. Outcome measures were evaluated as function of gas exchange, cardiovascular parameters, and lung mechanics including mean airway pressure (mP(aw)). Delata P(aw), V(T), V'(ins,max), V'(exp,max), and V'(E) measurements had correlation coefficients r = 1.00, and %error or = 0.98 and %error ventilated groups had increased mP(aw) and W(OB), with decreased V(T), V'(E), C(L,dyn), R(rs,MW), and R(rs,ele) compared to controls. After 1-h ventilation, both injured group had decreased V(T), V'(E) , and C(L,dyn), with increased mP(aw), R(rs,MW), R(rs,ele), and W(OB) . In lung-injured animals, liquid ventilation restored gas exchange, and cardiovascular and lung functions. Our lung mechanics system was able to closely monitor pulmonary function, including during transitions between gas and liquid phases.

  11. Infiltration Effects on Residential Pollutant Concentrations for Continuous and Intermittent Mechanical Ventilation Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max; Logue, Jennifer; Singer, Brett

    2010-06-01

    The prevailing residential ventilation standard in North America, American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62.2, specifies volumetric airflow requirements as a function of the overall size of the home and the number of bedrooms, assumes a fixed, minimal amount of infiltration, and requires mechanical ventilation to achieve the remainder. The standard allows for infiltration credits and intermittent ventilation patterns that can be shown to provide comparable performance. Whole-house ventilation methods have a substantial effect on time-varying indoor pollutant concentrations. If alternatives specified by Standard 62.2, such as intermittent ventilation, are used, short-term pollutant concentrations could exceed acute health standards even if chronic health standards are met.The authors present a methodology for comparing ASHRAE- and non-ASHRAE-specified ventilation scenarios on relative indoor pollutant concentrations. We use numerical modeling to compare the maximum time-averaged concentrations for acute exposure relevant (1-hour, 8-hour, 24-hour ) and chronic exposure relevant (1-year) time periods for four different ventilation scenarios in six climates with a range of normalized leakage values. The results suggest that long-term concentrations are the most important metric for assessing the effectiveness of whole-house ventilation systems in meeting exposure standards and that, if chronic health exposure standards are met, acute standards will also be met.

  12. Experimental Assessment of Mechanical Night Ventilation on Inner Wall Surfaces

    DEFF Research Database (Denmark)

    Wenhui, Ji; Heiselberg, Per Kvols; Wang, Houhua

    2016-01-01

    The cooling potential of night ventilation largely depends on the heat exchange at the internal room surfaces. During night time, increased heat transfer on a vertical wall is expected due to cool supply air that flows along the internal wall surface from the top of the wall. This paper presents ...

  13. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Science.gov (United States)

    2010-10-01

    ...-ferrous material. (3) The impeller and housing made of austenitic stainless steel. (4) The impeller and housing made of ferrous material with at least 13mm (0.512 in.) tip clearance. (j) No ventilation fan may have any combination of fixed or rotating components made of an aluminum or magnesium alloy and ferrous...

  14. State of the evidence: mechanical ventilation with PEEP in patients with cardiogenic shock.

    Science.gov (United States)

    Wiesen, Jonathan; Ornstein, Moshe; Tonelli, Adriano R; Menon, Venu; Ashton, Rendell W

    2013-12-01

    The need to provide invasive mechanical ventilatory support to patients with myocardial infarction and acute left heart failure is common. Despite the large number of patients requiring mechanical ventilation in this setting, there are remarkably few data addressing the ideal mode of respiratory support in such patients. Although there is near universal acceptance regarding the use of non-invasive positive pressure ventilation in patients with acute pulmonary oedema, there is more concern with invasive positive pressure ventilation owing to its more significant haemodynamic impact. Positive end-expiratory pressure (PEEP) is almost universally applied in mechanically ventilated patients due to benefits in gas exchange, recruitment of alveolar units, counterbalance of hydrostatic forces leading to pulmonary oedema and maintenance of airway patency. The limited available clinical data suggest that a moderate level of PEEP is safe to use in severe left ventricular (LV) dysfunction and cardiogenic shock, and may provide haemodynamic benefits as well in LV failure which exhibits afterload-sensitive physiology.

  15. Nursing of Mechanical Ventilation Patients with Withdrawal of Ventilator%机械通气患者撤离呼吸机的护理

    Institute of Scientific and Technical Information of China (English)

    陈静静; 程宝霞; 王鑫; 刘兰芬

    2011-01-01

    Objective To explore the nursing measures during the withdrawal of ventilator in patients with mechanical ventilation. Methods The nursing plan during the withdrawal of ventilator in patients with mechanical ventilation was summarized based on the clinical nursing science and combined with clinical practice. Results Safety and suitable nursing care is key to elevate the success rate of the withdrawal of ventilator in patients with mechanical ventilation up to 95%. Conclusion Strengthening the clinical nursing during the withdrawal of ventilator in patients with mechanical ventilation can contribute to the recovery of respiratory function for improving life quality of patients.%目的 探讨机械通气患者撤离呼吸机过程中的护理措施.方法 以临床护理学为基础,结合临床工作实践经验,总结机械通气患者撤离呼吸机过程的护理措施.结果 通过正确及安全的护理措施,机械通气患者撤离呼吸机的成功率提高至95%.结论 加强机械通气患者撤离呼吸机过程的护理,可帮助患者恢复正常自主呼吸功能,从而提高患者生活质量.

  16. Is pulmonary resistance constant, within the range of tidal volume ventilation, in patients with ARDS?

    Science.gov (United States)

    Mols, G; Kessler, V; Benzing, A; Lichtwarck-Aschoff, M; Geiger, K; Guttmann, J

    2001-02-01

    When managing patients with acute respiratory distress syndrome (ARDS), respiratory system compliance is usually considered first and changes in resistance, although recognized, are neglected. Resistance can change considerably between minimum and maximum lung volume, but is generally assumed to be constant in the tidal volume range (V(T)). We measured resistance during tidal ventilation in 16 patients with ARDS or acute lung injury by the slice method and multiple linear regression analysis. Resistance was constant within V(T) in only six of 16 patients. In the remaining patients, resistance decreased, increased or showed complex changes. We conclude that resistance within V(T) varies considerably from patient to patient and that constant resistance within V(T) is not always likely.

  17. Total liquid ventilation provides superior respiratory support to conventional mechanical ventilation in a large animal model of severe respiratory failure.

    Science.gov (United States)

    Pohlmann, Joshua R; Brant, David O; Daul, Morgan A; Reoma, Junewai L; Kim, Anne C; Osterholzer, Kathryn R; Johnson, Kent J; Bartlett, Robert H; Cook, Keith E; Hirschl, Ronald B

    2011-01-01

    Total liquid ventilation (TLV) has the potential to provide respiratory support superior to conventional mechanical ventilation (CMV) in the acute respiratory distress syndrome (ARDS). However, laboratory studies are limited to trials in small animals for no longer than 4 hours. The objective of this study was to compare TLV and CMV in a large animal model of ARDS for 24 hours. Ten sheep weighing 53 ± 4 (SD) kg were anesthetized and ventilated with 100% oxygen. Oleic acid was injected into the pulmonary circulation until PaO2:FiO2 ≤ 60 mm Hg, followed by transition to a protective CMV protocol (n = 5) or TLV (n = 5) for 24 hours. Pathophysiology was recorded, and the lungs were harvested for histological analysis. Animals treated with CMV became progressively hypoxic and hypercarbic despite maximum ventilatory support. Sheep treated with TLV maintained normal blood gases with statistically greater PO2 (p < 10(-9)) and lower PCO2 (p < 10(-3)) than the CMV group. Survival at 24 hours in the TLV and CMV groups were 100% and 40%, respectively (p < 0.05). Thus, TLV provided gas exchange superior to CMV in this laboratory model of severe ARDS.

  18. Human versus Computer Controlled Selection of Ventilator Settings: An Evaluation of Adaptive Support Ventilation and Mid-Frequency Ventilation

    Directory of Open Access Journals (Sweden)

    Eduardo Mireles-Cabodevila

    2012-01-01

    Full Text Available Background. There are modes of mechanical ventilation that can select ventilator settings with computer controlled algorithms (targeting schemes. Two examples are adaptive support ventilation (ASV and mid-frequency ventilation (MFV. We studied how different clinician-chosen ventilator settings are from these computer algorithms under different scenarios. Methods. A survey of critical care clinicians provided reference ventilator settings for a 70 kg paralyzed patient in five clinical/physiological scenarios. The survey-derived values for minute ventilation and minute alveolar ventilation were used as goals for ASV and MFV, respectively. A lung simulator programmed with each scenario’s respiratory system characteristics was ventilated using the clinician, ASV, and MFV settings. Results. Tidal volumes ranged from 6.1 to 8.3 mL/kg for the clinician, 6.7 to 11.9 mL/kg for ASV, and 3.5 to 9.9 mL/kg for MFV. Inspiratory pressures were lower for ASV and MFV. Clinician-selected tidal volumes were similar to the ASV settings for all scenarios except for asthma, in which the tidal volumes were larger for ASV and MFV. MFV delivered the same alveolar minute ventilation with higher end expiratory and lower end inspiratory volumes. Conclusions. There are differences and similarities among initial ventilator settings selected by humans and computers for various clinical scenarios. The ventilation outcomes are the result of the lung physiological characteristics and their interaction with the targeting scheme.

  19. Model-based PEEP optimisation in mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Chiew Yeong Shiong

    2011-12-01

    Full Text Available Abstract Background Acute Respiratory Distress Syndrome (ARDS patients require mechanical ventilation (MV for breathing support. Patient-specific PEEP is encouraged for treating different patients but there is no well established method in optimal PEEP selection. Methods A study of 10 patients diagnosed with ALI/ARDS whom underwent recruitment manoeuvre is carried out. Airway pressure and flow data are used to identify patient-specific constant lung elastance (Elung and time-variant dynamic lung elastance (Edrs at each PEEP level (increments of 5cmH2O, for a single compartment linear lung model using integral-based methods. Optimal PEEP is estimated using Elung versus PEEP, Edrs-Pressure curve and Edrs Area at minimum elastance (maximum compliance and the inflection of the curves (diminishing return. Results are compared to clinically selected PEEP values. The trials and use of the data were approved by the New Zealand South Island Regional Ethics Committee. Results Median absolute percentage fitting error to the data when estimating time-variant Edrs is 0.9% (IQR = 0.5-2.4 and 5.6% [IQR: 1.8-11.3] when estimating constant Elung. Both Elung and Edrs decrease with PEEP to a minimum, before rising, and indicating potential over-inflation. Median Edrs over all patients across all PEEP values was 32.2 cmH2O/l [IQR: 26.1-46.6], reflecting the heterogeneity of ALI/ARDS patients, and their response to PEEP, that complicates standard approaches to PEEP selection. All Edrs-Pressure curves have a clear inflection point before minimum Edrs, making PEEP selection straightforward. Model-based selected PEEP using the proposed metrics were higher than clinically selected values in 7/10 cases. Conclusion Continuous monitoring of the patient-specific Elung and Edrs and minimally invasive PEEP titration provide a unique, patient-specific and physiologically relevant metric to optimize PEEP selection with minimal disruption of MV therapy.

  20. Non-invasive versus invasive mechanical ventilation for respiratory failure in severe acute respiratory syndrome

    Institute of Scientific and Technical Information of China (English)

    Loretta YC Yam; Alfred YF Chan; Thomas MT Cheung; Eva LH Tsui; Jane CK Chan; Vivian CW Wong

    2005-01-01

    Background Severe acute respiratory syndrome is frequently complicated by respiratory failure requiring ventilatory support. We aimed to compare the efficacy of non-invasive ventilation against invasive mechanical ventilation treating respiratory failure in this disease. Methods Retrospective analysis was conducted on all respiratory failure patients identified from the Hong Kong Hospital Authority Severe Acute Respiratory Syndrome Database. Intubation rate, mortality and secondary outcome of a hospital utilizing non-invasive ventilation under standard infection control conditions (NIV Hospital) were compared against 13 hospitals using solely invasive ventilation (IMV Hospitals). Multiple logistic regression analyses with adjustments for confounding variables were performed to test for association between outcomes and hospital groups. Results Both hospital groups had comparable demographics and clinical profiles, but NIV Hospital (42 patients) had higher lactate dehydrogenase ratio and worse radiographic score on admission and ribavirin-corticosteroid commencement. Compared to IMV Hospitals (451 patients), NIV Hospital had lower adjusted odds ratios for intubation (0.36, 95% CI 0.164-0.791, P=0.011) and death (0.235, 95% CI 0.077-0.716, P=0.011), and improved earlier after pulsed steroid rescue. There were no instances of transmission of severe acute respiratory syndrome among health care workers due to the use of non-invasive ventilation.Conclusion Compared to invasive mechanical ventilation, non-invasive ventilation as initial ventilatory support for acute respiratory failure in the presence of severe acute respiratory syndrome appeared to be associated with reduced intubation need and mortality.

  1. Non-conventional mechanical ventilation in severe ARDS, illustrated by a complicated case

    NARCIS (Netherlands)

    Tulleken, JE; van der Werf, TS; Ligtenberg, JJM; Zijlstra, JG

    1998-01-01

    When conventional respiratory strategies fail to maintain adequate oxygenation treatment of severe ARDS is largely empirical. Modern techniques such as inverse ratio ventilation, permissive hypercapnia, NO inhalation and lowering tidal volumes/pressures are advocated. We report on a patient with sev

  2. Incidence and risk factors of upper gastrointestinal bleeding in mechanically ventilated children.

    Science.gov (United States)

    Deerojanawong, Jitladda; Peongsujarit, Danayawan; Vivatvakin, Boosba; Prapphal, Nuanchan

    2009-01-01

    To identify the incidence and factors related to upper gastrointestinal (UGI) bleeding in children requiring mechanical ventilation for longer than 48 hrs. Prospective analytic study. Ten-bed-pediatric intensive care unit of a tertiary care University Hospital. A total of 110 patients requiring mechanical ventilation for longer than 48 hrs from January 1, 2005 to December 31, 2005. UGI bleeding was defined by evidence of blood in nasogastric aspirates, hematemesis, or melena within 5 days of pediatric intensive care unit admission. We prospectively collected data on patient demographics, admission diagnosis, operative status, and pediatric risk of mortality score. UGI bleeding and the potential risk factors including organ failure, coagulopathy, maximum ventilator setting, enteral feeding, stress ulcer prophylaxis as well as sedation were daily monitored. Of the 110 patients who required mechanical ventilation for >48 hrs, the incidence of UGI bleeding was 51.8%, in which 3.6% of the cases presented with clinically significant bleeding (shock, requiring blood transfusion and/or surgery). Significant risk factors were thrombocytopenia, prolonged partial thromboplastin time, organ failure, high pressure ventilator setting >/=25 cm H2O, and pediatric risk of mortality score >/= 10 using univariate analysis. However, the independent factors of UGI bleeding in the multivariate analysis were organ failure (relative risk = 2.85, 95% confidence interval 1.18-6.92) and high pressure ventilator setting >/=25 cm H2O (relative risk = 3.73, 95% confidence interval 1.59-8.72). The incidence of UGI bleeding is high in children requiring mechanical ventilation. Organ failure and high pressure ventilator setting are significant risk factors for UGI bleeding.

  3. Anticipation of distress after discontinuation of mechanical ventilation in the ICU at the end of life

    OpenAIRE

    Kompanje, Erwin; van der Hoven, Ben; Bakker, Jan

    2008-01-01

    textabstractBackground: A considerable number of patients admitted to the intensive care unit (ICU) die following withdrawal of mechanical ventilation. After discontinuation of ventilation without proper preparation, excessive respiratory secretion is common, resulting in a 'death rattle'. Post-extubation stridor can give rise to the relatives' perception that the patient is choking and suffering. Existing protocols lack adequate anticipatory preparation to respond to all distressing symptoms...

  4. Very Low Birth Weight Infant Necessitating Nissen Fundoplication for Weaning off the Mechanical Ventilator

    Directory of Open Access Journals (Sweden)

    İpek Güney Varal

    2014-05-01

    Full Text Available Gastro-esophageal reflux (GER is one of the common problems of neonatal intensive care units. Although this condition does not always need to be treated, it occasionally causes clinically serious consequences. Initial management is medical; however, in some cases surgery might be required. A premature neonate with birth weight of 1370 grams was managed in our ICU. The patient was mechanical ventilator dependent due to GER. The patient needed Nissen fundoplication for successfully weaning off the ventilator.

  5. Altered diaphragmatic contractile properties after high airway pressure controlled mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Acute respiratory failure is the most frequent indication for the application of mechanical ventilation. 1 As commonly used in clinical settings, lung protective strategies and recruitment manoeuvres are applications of higher than normal airway pressure to open the collapsed alveoli and prevent lung atelectasis caused by minimal vital ventilation. Under those conditions, we pay more attention to the lung injury and circulatory failure, and less attention to the diaphragmatic structure and function.

  6. Effect of Minimally Invasive Surfactant Therapy on Lung Volume and Ventilation in Preterm Infants.

    Science.gov (United States)

    van der Burg, Pauline S; de Jongh, Frans H; Miedema, Martijn; Frerichs, Inez; van Kaam, Anton H

    2016-03-01

    To assess the changes in (regional) lung volume and gas exchange during minimally invasive surfactant therapy (MIST) in preterm infants with respiratory distress syndrome. In this prospective observational study, infants requiring a fraction of inspired oxygen (FiO2) ≥ 0.30 during nasal continuous positive airway pressure of 6 cmH2O were eligible for MIST. Surfactant (160-240 mg/kg) was administered in supine position in 1-3 minutes via an umbilical catheter placed 2 cm below the vocal cords. Changes in end-expiratory lung volume (EELV), tidal volume, and its distribution were recorded continuously with electrical impedance tomography before and up to 60 minutes after MIST. Changes in transcutaneous oxygen saturation (SpO2) and partial carbon dioxide pressure, FiO2, respiratory rate, and minute ventilation were recorded. A total of 16 preterm infants were included. One patient did not finish study protocol because of severe apnea 10 minutes after MIST. In the remaining infants (gestational age 29.8 ± 2.8 weeks, body weight 1545 ± 481 g) EELV showed a rapid and sustained increase, starting in the dependent lung regions, followed by the nondependent regions approximately 5 minutes later. Oxygenation, expressed as the SpO2/FiO2 ratio, increased from 233 (IQR 206-257) to 418 (IQR 356-446) after 60 minutes (P transcutaneous partial carbon dioxide pressure was comparable with pre-MIST values. Ventilation distribution remained unchanged. MIST results in a rapid and homogeneous increase in EELV, which is associated with an improvement in oxygenation. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Cough augmentation techniques for extubation or weaning critically ill patients from mechanical ventilation.

    Science.gov (United States)

    Rose, Louise; Adhikari, Neill Kj; Leasa, David; Fergusson, Dean A; McKim, Douglas

    2017-01-11

    There are various reasons why weaning and extubation failure occur, but ineffective cough and secretion retention can play a significant role. Cough augmentation techniques, such as lung volume recruitment or manually- and mechanically-assisted cough, are used to prevent and manage respiratory complications associated with chronic conditions, particularly neuromuscular disease, and may improve short- and long-term outcomes for people with acute respiratory failure. However, the role of cough augmentation to facilitate extubation and prevent post-extubation respiratory failure is unclear. Our primary objective was to determine extubation success using cough augmentation techniques compared to no cough augmentation for critically-ill adults and children with acute respiratory failure admitted to a high-intensity care setting capable of managing mechanically-ventilated people (such as an intensive care unit, specialized weaning centre, respiratory intermediate care unit, or high-dependency unit).Secondary objectives were to determine the effect of cough augmentation techniques on reintubation, weaning success, mechanical ventilation and weaning duration, length of stay (high-intensity care setting and hospital), pneumonia, tracheostomy placement and tracheostomy decannulation, and mortality (high-intensity care setting, hospital, and after hospital discharge). We evaluated harms associated with use of cough augmentation techniques when applied via an artificial airway (or non-invasive mask once extubated/decannulated), including haemodynamic compromise, arrhythmias, pneumothorax, haemoptysis, and mucus plugging requiring airway change and the type of person (such as those with neuromuscular disorders or weakness and spinal cord injury) for whom these techniques may be efficacious. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; Issue 4, 2016), MEDLINE (OvidSP) (1946 to April 2016), Embase (OvidSP) (1980 to April 2016), CINAHL (EBSCOhost) (1982

  8. Activation of the Wnt/β-catenin signaling pathway by mechanical ventilation is associated with ventilator-induced pulmonary fibrosis in healthy lungs.

    Directory of Open Access Journals (Sweden)

    Jesús Villar

    Full Text Available BACKGROUND: Mechanical ventilation (MV with high tidal volumes (V(T can cause or aggravate lung damage, so-called ventilator induced lung injury (VILI. The relationship between specific mechanical events in the lung and the cellular responses that result in VILI remains incomplete. Since activation of Wnt/β-catenin signaling has been suggested to be central to mechanisms of lung healing and fibrosis, we hypothesized that the Wnt/β-catenin signaling plays a role during VILI. METHODOLOGY/PRINCIPAL FINDINGS: Prospective, randomized, controlled animal study using adult, healthy, male Sprague-Dawley rats. Animals (n = 6/group were randomized to spontaneous breathing or two strategies of MV for 4 hours: low tidal volume (V(T (6 mL/kg or high V(T (20 mL/kg. Histological evaluation of lung tissue, measurements of WNT5A, total β-catenin, non-phospho (Ser33/37/Thr41 β-catenin, matrix metalloproteinase-7 (MMP-7, cyclin D1, vascular endothelial growth factor (VEGF, and axis inhibition protein 2 (AXIN2 protein levels by Western blot, and WNT5A, non-phospho (Ser33/37/Thr41 β-catenin, MMP-7, and AXIN2 immunohistochemical localization in the lungs were analyzed. High-V(T MV caused lung inflammation and perivascular edema with cellular infiltrates and collagen deposition. Protein levels of WNT5A, non-phospho (Ser33/37/Thr41 β-catenin, MMP-7, cyclin D1, VEGF, and AXIN2 in the lungs were increased in all ventilated animals although high-V(T MV was associated with significantly higher levels of WNT5A, non-phospho (Ser33/37/Thr41 β-catenin, MMP-7, cyclin D1, VEGF, and AXIN2 levels. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that the Wnt/β-catenin signaling pathway is modulated very early by MV in lungs without preexistent lung disease, suggesting that activation of this pathway could play an important role in both VILI and lung repair. Modulation of this pathway might represent a therapeutic option for prevention and/or management of VILI.

  9. [Diuretic resistance and mechanical ventilation in decompensated cor pulmonale: successful treatment by slow continuous ultrafiltration].

    Science.gov (United States)

    Ries, W; Schenzer, A; Lüken, J; Ries, C; Machraoui, A

    2012-08-01

    We report on a 53-year-old male patient who presented with severe dyspnea at rest and massive volume overload because of decompensated cor pulmonale. Furthermore he suffered from stage 3 chronic kidney disease. As there was diuretics resistance and carbon dioxide narcosis, he had to be intubated and ventilated. The massive volume overload could be successfully treated with slow continuous ultrafiltration (SCUF) with removal of a volume of 27.5 l within 3 days. The SCUF therapy is an effective and gentle method to treat even an excessive volume overload based on diuretics resistance.

  10. Very early passive cycling exercise in mechanically ventilated critically ill patients: physiological and safety aspects--a case series.

    Directory of Open Access Journals (Sweden)

    Ruy Camargo Pires-Neto

    Full Text Available INTRODUCTION: Early mobilization can be performed in critically ill patients and improves outcomes. A daily cycling exercise started from day 5 after ICU admission is feasible and can enhance functional capacity after hospital discharge. In the present study we verified the physiological changes and safety of an earlier cycling intervention (< 72 hrs of mechanical ventilation in critical ill patients. METHODS: Nineteen hemodynamically stable and deeply sedated patients within the first 72 hrs of mechanical ventilation were enrolled in a single 20 minute passive leg cycling exercise using an electric cycle ergometer. A minute-by-minute evaluation of hemodynamic, respiratory and metabolic variables was undertaken before, during and after the exercise. Analyzed variables included the following: cardiac output, systemic vascular resistance, central venous blood oxygen saturation, respiratory rate and tidal volume, oxygen consumption, carbon dioxide production and blood lactate levels. RESULTS: We enrolled 19 patients (42% male, age 55 ± 17 years, SOFA = 6 ± 3, SAPS3 score = 58 ± 13, PaO2/FIO2 = 223 ± 75. The median time of mechanical ventilation was 1 day (02, and 68% (n=13 of our patients required norepinephrine (maximum concentration = 0.47 µg.kg(-1.min(-1. There were no clinically relevant changes in any of the analyzed variables during the exercise, and two minor adverse events unrelated to hemodynamic instability were observed. CONCLUSIONS: In our study, this very early passive cycling exercise in sedated, critically ill, mechanically ventilated patients was considered safe and was not associated with significant alterations in hemodynamic, respiratory or metabolic variables even in those requiring vasoactive agents.

  11. The use of 2% chlorhexidine gel and toothbrushing for oral hygiene of patients receiving mechanical ventilation: effects on ventilator-associated pneumonia

    Science.gov (United States)

    Meinberg, Maria Cristina de Avila; Cheade, Maria de Fátima Meinberg; Miranda, Amanda Lucia Dias; Fachini, Marcela Mascaro; Lobo, Suzana Margareth

    2012-01-01

    Objective To evaluate the effects of oral chlorhexidine hygiene with toothbrushing on the rate of ventilator-associated pneumonia in a mixed population of critically ill patients under prolonged mechanical ventilation. Methods Prospective, randomized, and placebo-controlled pilot study. Patients who were receiving mechanical ventilation, had been admitted less than 24 hours prior, and were anticipated to require mechanical ventilation for more than 72 hours were included in the study. The patients were randomly divided into one of the following groups: chlorhexidine hygiene with toothbrushing or a placebo group (gel with the same color and consistency and toothbrushing). Results The planned interim analysis was conducted using 52 patients, and the study was terminated prematurely. In total, 28 patients were included in the chlorhexidine / toothbrushing group, and 24 patients were included in the placebo group. Ventilator-associated pneumonia occurred in 45.8% of the placebo group and in 64.3% of the chlorhexidine hygiene with toothbrushing group (RR=1.4; 95% CI=0.83-2.34; p=0.29). Conclusion Because the study was terminated due to futility, it was not possible to evaluate the impact of oral hygiene using 2% chlorhexidine and toothbrushing on the incidence of ventilator-associated pneumonia in this heterogeneous population of critical patients receiving long-term mechanical ventilation, and no beneficial effect was observed for this intervention. PMID:23917935

  12. The influence of mechanical ventilation on physiological parameters in ball pythons (Python regius).

    Science.gov (United States)

    Jakobsen, Sashia L; Williams, Catherine J A; Wang, Tobias; Bertelsen, Mads F

    2017-05-01

    Mechanical ventilation is widely recommended for reptiles during anesthesia, and while it is well-known that their low ectothermic metabolism requires much lower ventilation than in mammals, very little is known about the influence of ventilation protocol on the recovery from anesthesia. Here, 15 ball pythons (Python regius) were induced and maintained with isoflurane for 60min at one of three ventilation protocols (30, 125, or 250mlmin(-1)kg(-1) body mass) while an arterial catheter was inserted, and ventilation was then continued on 100% oxygen at the specified rate until voluntary extubation. Mean arterial blood pressure and heart rate (HR) were measured, and arterial blood samples collected at 60, 80, 180min and 12 and 24h after intubation. In all three groups, there was evidence of a metabolic acidosis, and snakes maintained at 30mlmin(-1)kg(-1) experienced an additional respiratory acidosis, while the two other ventilation protocols resulted in normal or low arterial PCO2. In general, normal acid-base status was restored within 12h in all three protocols. HR increased by 143±64% during anesthesia with high mechanical ventilation (250mlmin(-1)kg(-1)) in comparison with recovered values. Recovery times after mechanical ventilation at 30, 125, or 250mlmin(-1)kg(-1) were 289±70, 126±16, and 68±7min, respectively. Mild overventilation may result in a faster recovery, and the associated lowering of arterial PCO2 normalised arterial pH in the face of metabolic acidosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Effect of noninvasive positive pressure ventilation on weaning success in patients receiving invasive mechanical ventilation: a meta-analysis

    Institute of Scientific and Technical Information of China (English)

    ZHU Fen; LIU Zi-long; LONG Xuan; WU Xiao-dan; ZHOU Jing; BAI Chun-xue; LI Shan-qun

    2013-01-01

    Background Noninvasive positive pressure ventilation (NIPPV) has been proposed to shorten the duration of mechanical ventilation in intubated patients,especially those who fail initial weaning from invasive mechanical ventilation (IMV).However,there are also some discrepancies in terms of weaning success or failure,incidence of re-intubation,complications observed during study and patient outcomes.The primary objective of this update was to specifically investigate the role of NIPPV on facilitating weaning and avoiding re-intubation in patients intubated for different etiologies of acute respiratory failure,by comparing with conventional invasive weaning approach.Methods We searched randomized controlled trials (RCTs) comparing noninvasive weaning of early extubation and immediate application of NIPPV with invasive weaning in intubated patients from PubMed,Embase,Cochrane Central Register of Controlled Trials,Web of Knowledge and Springerlink databases.Records from conference proceedings and reference lists of relevant studies were also identified.Results A total of 11 RCTs with 623 patients were available for the present analysis.Compared with IMV,NIPPV significantly increased weaning success rates (odds ratio (OR):2.50,95% confidence interval (C/):1.46-4.30,P=0.0009),decreased mortality (OR:0.39,95% CI:0.20-0.75,P=0.005),and reduced the incidence of ventilator associated pneumonia (VAP) (OR:0.17,95% CI:0.08-0.37,P <0.00001) and complications (OR:0.22,95% CI:0.07-0.72,P=0.01).However,effect of NIPPV on re-intubation did not reach statistical difference (OR:0.61,95% CI:0.33-1.11,P=0.11).Conclusions Early extubation and immediate application of NIPPV is superior to conventional invasive weaning approach in increasing weaning success rates,decreasing the risk of mortality and reducing the incidence of VAP and complications,in patients who need weaning from IMV.However,it should be applied with caution,as there is insufficient beneficial evidence to

  14. The use of dexmedetomidine combined with propofol in mechanically ventilated patients

    Directory of Open Access Journals (Sweden)

    Zi-long HU

    2015-07-01

    Full Text Available Objective To estimate and compare the efficacy and safety of midazolam, propofol and dexmedetomidine combined with propofol in sedation for mechanically ventilated patients. Methods Seventy-six patients with mechanical ventilation time >24h in ICU of Navy General Hospital of PLA from Mar. 2012 to Sep. 2014 were randomly divided into midazolam group (n=23, propofol group (n=27 and dexmedetomidine combined with propofol group (n=26, and they were given corresponding drugs for sedation. The proportions in each group which reached the target score of Richmond agitation-sedation scale (RASS and the nonverbal pain assessment scale (Critical-Care Pain Observation Tool, CPOT were accounted and recorded, and the positive rate of delirium was assessed with the confusion assessment method in the intensive care unit (CAM-ICU. The mechanical ventilation time and the effectiveness of sedation among the 3 groups were compared, the frequency of adverse cardiovascular events was recorded, and the frequency of controlled ventilation, daily mean arterial pressure as well as the heart rate range were analyzed. Results The proportion of reaching the target score of RASS was higher in dexmedetomidine combined with propofol group (86.54% than that in midazolam group (69.32%, P0.05. The proportion of reaching the target score of CPOT was higher in dexmedetomidine combined with propofol group (63.1% than in midazolam group (51.2% and propofol group (49.5%, P0.05. The positive rate of delirium and the proportion of controlled ventilation were lower, and the time of mechanical ventilation is shorter in dexmedetomidine combined with propofol group than in the other two groups (P0.05. Conclusion The efficacy and safety of dexmedetomidine combined with propofol is higher than the individual use of midazolam or propofol in producing sedation for mechanically ventilated patients. DOI: 10.11855/j.issn.0577-7402.2015.06.12

  15. Acute respiratory failure and mechanical ventilation in pregnant patient: A narrative review of literature

    Directory of Open Access Journals (Sweden)

    Pradeep Kumar Bhatia

    2016-01-01

    Full Text Available Physiological changes of pregnancy imposes higher risk of acute respiratory failure (ARF with even a slight insult and remains an important cause of maternal and fetal morbidity and mortality. Although pregnant women have different respiratory physiology and different causes of ARF, guidelines specific to ventilatory settings, goals of oxygenation and weaning process could not be framed due to lack of large-scale randomized controlled trials. During the 2009 H1N1 pandemic, pregnant women had higher morbidity and mortality compared to nonpregnant women. During this period, alternative strategies of ventilation such as high-frequency oscillatory ventilation, inhalational of nitric oxide, prone positioning, and extra corporeal membrane oxygenation were increasingly used as a desperate measure to rescue pregnant patients with severe hypoxemia who were not improving with conventional mechanical ventilation. This article highlights the causes of ARF and recent advances in invasive, noninvasive and alternative strategies of ventilation used during pregnancy.

  16. Outcome of mechanically ventilated patients initially denied admission to an intensive care unit and subsequently admitted.

    Science.gov (United States)

    Naser, Wasim; Schwartz, Naama; Finkelstein, Richard; Bisharat, Naiel

    2016-11-01

    The outcome of mechanically ventilated patients initially denied admission to an intensive care unit (ICU) and subsequently admitted is unclear. We compared outcomes of patients denied ICU admission and subsequently admitted, to those of patients admitted to the ICU and to patients refused ICU admission. The medical records of all the patients who were subjected to mechanical ventilation for at least 24h over a 4year period (2010-2014) were reviewed. Of 707 patients (757 admissions), 124 (18%) were initially denied ICU admission and subsequently admitted. Multivariate stepwise logistic regression analysis showed significant association with death of: age, length of stay, nursing home residency, duration of mechanical ventilation, previous admission with mechanical ventilation, cause for mechanical ventilation, rate of failed extubations, associated morbidity (previous cerebrovascular accident, dementia, chronic renal failure), and occurrence of nosocomial bacteremia. The odds for death among patients denied ICU admission and subsequently transferred to the ICU compared to patients admitted directly to the ICU was 3.6 (95% CI: 1.9-6.7) (Padmission compared to those who were initially denied and subsequently admitted were not statistically significant (OR=1.7, 95% CI: 0.8-3.8). In conclusion, patients denied ICU admission and subsequently admitted face a considerable risk of morbidity and mortality. Their odds of death are nearly three times those admitted directly to the ICU. Late admission to the ICU does not appear to provide benefit compared to patients who remain in general medicine wards.

  17. Assessment of Indoor Air Quality Benefits and Energy Costs of Mechanical Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Logue, J.M.; Price, P.N.; Sherman, M.H.; Singer, B.C.

    2011-07-01

    Intake of chemical air pollutants in residences represents an important and substantial health hazard. Sealing homes to reduce air infiltration can save space conditioning energy, but can also increase indoor pollutant concentrations. Mechanical ventilation ensures a minimum amount of outdoor airflow that helps reduce concentrations of indoor emitted pollutants while requiring some energy for fan(s) and thermal conditioning of the added airflow. This work demonstrates a physics based, data driven modeling framework for comparing the costs and benefits of whole-house mechanical ventilation and applied the framework to new California homes. The results indicate that, on a population basis, the health benefits from reduced exposure to indoor pollutants in New California homes are worth the energy costs of adding mechanical ventilation as specified by ASHRAE Standard 62.2.This study determines the health burden for a subset of pollutants in indoor air and the costs and benefits of ASHRAE's mechanical ventilation standard (62.2) for new California homes. Results indicate that, on a population basis, the health benefits of new home mechanical ventilation justify the energy costs.

  18. The Influence of Fluid Overload on the Length of Mechanical Ventilation in Pediatric Congenital Heart Surgery.

    Science.gov (United States)

    Sampaio, Tatiana Z A L; O'Hearn, Katie; Reddy, Deepti; Menon, Kusum

    2015-12-01

    Fluid overload and prolonged mechanical ventilation lead to worse outcomes in critically ill children. However, the association between these variables in children following congenital heart surgery is unknown. The objectives of this study were to describe the association between fluid overload and duration of mechanical ventilation, oxygen requirement and radiologic findings of pulmonary and chest wall edema. This study is a retrospective chart review of patients who underwent congenital heart surgery between June 2010 and December 2013. Univariate and multivariate associations between maximum cumulative fluid balance and length of mechanical ventilation and OI were tested using the Spearman correlation test and multiple linear regression models, respectively. There were 85 eligible patients. Maximum cumulative fluid balance was associated with duration of mechanical ventilation (adjusted analysis beta coefficient = 0.53, CI 0.38-0.66, P Fluid overload is associated with prolonged duration of mechanical ventilation and PICU length of stay after congenital heart surgery. Fluid overload was also associated with physiological markers of respiratory restriction. A randomized controlled trial of a restrictive versus liberal fluid replacement strategy is necessary in this patient population, but in the meantime, accumulating observational evidence suggests that cautious use of fluid in the postoperative care may be warranted.

  19. Pulmonary Drug Delivery System for inhalation therapy in mechanically ventilated patients.

    Science.gov (United States)

    Dhand, Rajiv; Sohal, Harjyot

    2008-01-01

    The Pulmonary Drug Delivery System (PDDS) Clinical represents a newer generation of electronic nebulizers that employ a vibrating mesh or aperture plate to generate an aerosol. The PDDS Clinical is designed for aerosol therapy in patients receiving mechanical ventilation. The components of the device include a control module that is connected to the nebulizer/reservoir unit by a cable. The nebulizer contains Aerogen's OnQ aerosol generator. A pressure sensor monitors the pressure in the inspiratory limb of the ventilator circuit and provides feedback to the control module. Based on the feedback from the pressure sensor, aerosol generation occurs only during a specific part of the respiratory cycle. In bench models, the PDDS Clinical has high efficiency for aerosol delivery both on and off the ventilator, with a lower respiratory tract delivery of 50-70% of the nominal dose. Currently, the PDDS Clinical is being evaluated for the treatment of ventilator-associated pneumonia with aerosolized amikacin, an aminoglycoside antibiotic. Preliminary studies in patients with ventilator-associated pneumonia found that the administration of amikacin via PDDS reduced the need for concomitant intravenous antibiotics; however, more definitive clinical studies are needed. The PDDS Clinical delivers a high percentage of the nominal dose to the lower respiratory tract, and is well suited for inhalation therapy in mechanically ventilated patients.

  20. 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.

  1. Haemodynamic stability and pulmonary shunt during spontaneous breathing and mechanical ventilation in porcine lung collapse.

    Science.gov (United States)

    Vimláti, L; Larsson, A; Hedenstierna, G; Lichtwarck-Aschoff, M

    2012-07-01

    We investigated the haemodynamic stability of a novel porcine model of lung collapse induced by negative pressure application (NPA). A secondary aim was to study whether pulmonary shunt correlates with cardiac output (CO). In 12 anaesthetized and relaxed supine piglets, lung collapse was induced by NPA (-50 kPa). Six animals resumed spontaneous breathing (SB) after 15 min; the other six animals were kept on mechanical ventilation (MV) at respiratory rate and tidal volume (V(T) ) that corresponded to SB. All animals were followed for 135 min with blood gas analysis and detailed haemodynamic monitoring. Haemodynamics and gas exchange were stable in both groups during the experiment with arterial oxygen tension (PaO(2) )/inspired fraction of oxygen (FiO(2) ) and pulmonary artery occlusion pressure being higher, venous admixture (Q(va) /Q(t) ) and pulmonary perfusion pressure being lower in the SB group. CO was similar in both groups, showing slight decrease over time in the SB group. During MV, Q(va) /Q(t) increased with CO (slope: 4.3 %min/l; P slope: 0.55 %min/l; P = 0.16). This porcine lung collapse model is reasonably stable in terms of haemodynamics for at least 2 h irrespective of the mode of ventilation. SB achieves higher PaO(2) /FiO(2) and lower Q(va) /Q(t) compared with MV. During SB, Q(va) /Q(t) seems to be less, if at all, affected by CO compared with MV. © 2012 The Authors. Acta Anaesthesiologica Scandinavica © 2012 The Acta Anaesthesiologica Scandinavica Foundation.

  2. Efficacy of Hi-Lo Evac Endotracheal Tube in Prevention of Ventilator-Associated Pneumonia in Mechanically Ventilated Poisoned Patients

    Science.gov (United States)

    Mashayekhian, Mohammad; Rahimi, Mitra; Aghabiklooei, Abbas

    2016-01-01

    Background. Ventilator-associated pneumonia (VAP) is the most common health care-associated infection. To prevent this complication, aspiration of subglottic secretions using Hi-Lo Evac endotracheal tube (Evac ETT) is a recommended intervention. However, there are some reports on Evac ETT dysfunction. We aimed to compare the incidence of VAP (per ventilated patients) in severely ill poisoned patients who were intubated using Evac ETT versus conventional endotracheal tubes (C-ETT) in our toxicology ICU. Materials and Methods. In this clinical randomized trial, 91 eligible patients with an expected duration of mechanical ventilation of more than 48 hours were recruited and randomly assigned into two groups: (1) subglottic secretion drainage (SSD) group who were intubated by Evac ETT (n = 43) and (2) control group who were intubated by C-ETT (n = 48). Results. Of the 91 eligible patients, 56 (61.5%) were male. VAP was detected in 24 of 43 (55.8%) patients in the case group and 23 of 48 (47.9%) patients in the control group (P = 0.45). The most frequently isolated microorganisms were S. aureus (54.10%) and Acinetobacter spp. (19.68%). The incidence of VAP and ICU length of stay were not significantly different between the two groups, but duration of intubation was statistically different and was longer in the SSD group. Mortality rate was less in SSD group but without a significant difference (P = 0.68). Conclusion. The SSD procedure was performed intermittently with one-hour intervals using 10 mL syringe. Subglottic secretion drainage does not significantly reduce the incidence of VAP in patients receiving MV. This strategy appears to be ineffective in preventing VAP among ICU patients. PMID:27651976

  3. Respiratory severity score on day of life 30 is predictive of mortality and the length of mechanical ventilation in premature infants with protracted ventilation.

    Science.gov (United States)

    Malkar, Manish B; Gardner, William P; Mandy, George T; Stenger, Michael R; Nelin, Leif D; Shepherd, Edward G; Welty, Stephen E

    2015-04-01

    We tested the hypothesis that Respiratory Severity Score (RSS) on day of life 30 is predictive of mortality and length of mechanical ventilation in premature infants on prolonged mechanical ventilation. A retrospective chart review was performed using the Nationwide Children's Hospital medical record and Vermont-Oxford Network databases. The primary outcome variable was survival to hospital discharge and the secondary outcome was length of mechanical ventilation after day of life 30. We identified 199 neonates admitted to Nationwide Children's Hospital between 2004 and 2007 with birth weight less than 1,500 g that received prolonged mechanical ventilation in the first 30 days of their life. A total of 184 infants were included in the analysis, excluding 14 patients with congenital anomalies and one infant with incomplete data. RSS on day of life 30 was significantly greater in the group of infants that died compared to those that survived (P = 0.003, 95% CI = [0.08, 0.40]). Further analysis demonstrated that the maximum difference in mortality was obtained with a threshold RSS of 6. Of the 109 patients who had RSS less than 6 on day of life 30, mortality rate was 4.6% (5/109) while those greater than or equal to 6 had a mortality rate of 21.3% (16/75). Both Kaplan-Meier survival curves comparing mortality and length of mechanical ventilation in infants with RSS < 6 versus those with RSS ≥ 6 demonstrated strong associations between RSS on day of life 30 and survival (P = 0.002) and length of ventilation after day of life 30 (P < 0.001). RSS ≥ 6 on day of life 30 is associated with higher mortality and longer period of mechanical ventilation in premature infants requiring mechanical ventilation through 30 days of life. © 2014 Wiley Periodicals, Inc.

  4. Effect of different tidal volume on respiratory mechanics and blood gas in lung cancer patients during one lung ventilation%单肺通气时不同潮气量对肺癌根治术患者呼吸力学及血气的影响

    Institute of Scientific and Technical Information of China (English)

    林飞; 潘灵辉; 钱卫; 杜学柯; 裴圣林; 陈肖东

    2012-01-01

    Objective To study the effect of different tidal volume on respiratory mechanics and blood gas in lung cancer patients with single lung ventilation. Methods 45 lung cancer patients were selected to execute radical operation, and put into double lumen endobronchial intubation after induction of anesthesia. The patients were randomly divided into three groups in the case of minute ventilation quantity invariable during intraoperative of one-lung ventilation; group A(VT = 10 mL/kg,f = 12/min), group B(VT = 8 mL/kg,f = 15/min) and group C(VT = 6 mL/kg,f = 20/min). Intraoperative continuous monitoring PETCO2、 Ppeak 、 Raw and extracting the arterial bloods for blood gas analysis before OLV, 30 min after OLV, 1 min before the end of OLV (Tl, T2, T3 ). Results Compared with Tl, Ppeak and Raw at T2, T3 significantly increased during the OLV(P < 0.05). Among three groups, Ppeak and Raw decreased gradually with the VT reduction during OLV, Ppeak and Raw were least in group C, and Ppeak and Raw in group A were significantly higher than those in group B, C (P < 0.05). PeiCO2 at T3 significantly increased than those at Tl, T2(P < 0.05), and PeiCO2 in group C was significantly higher than those in group A, B during the OLV (P < 0.05). Compared with T1, PaO2 were decreased, while PaC02 showed ascendant trend after OLV. PaO2 was significantly lower than that in group A and B (P < 0.01), and PaCO2 in group C significantly increased than that in group A and B (P < 0.05). Conclusion Using the ventilation way of group B(VT= 8 mL/ kg, f = 15/min ) is more appropriate in radical operation for lung cancer with one-lung ventilation.%观察在肺癌根治术中单肺通气(OLV)时不同潮气量(VT)对呼吸力学和血气值的影响.方法:选择45例择期行肺癌根治术的患者,行双腔支气管插管麻醉,术中OLV期间在保持分钟通气量不变的情况下,随机分为3组(每组15例):A组(VT=10 mL/kg,f=12次/min)、B组(VT=8 mL/kg,f=15次/min)、C组(VT=6m

  5. Noninvasive mechanical ventilation with high pressure strategy remains a “double edged sword”?

    Directory of Open Access Journals (Sweden)

    Esquinas AM

    2013-05-01

    Full Text Available Antonio M Esquinas,1 Gherardo Siscaro,2 Enrico M Clini21Intensive Care Unit, Hospital Morales Meseguer, Murcia, 2Department of Medical and Surgical Sciences, University of Modena, Pavullo-Modena, ItalyWe read with great interest the original work by Murphy et al analyzing the effects of two treatment strategies for delivery of noninvasive mechanical ventilation in hypercapnic patients with chronic obstructive pulmonary disease.1 High pressure and high intensity noninvasive mechanical ventilation were compared in a short-term crossover trial to assess whether high intensity noninvasive mechanical ventilation (inspiratory pressure > 25 cm H2O associated with a high backup ventilator rate may improve adherence, physiological, and subjective outcomes when compared with delivery of high pressure noninvasive mechanical ventilation (without elevated backup respiratory rate. The authors concluded that both strategies are equivalent in all the recorded outcomes, showing thus that driving pressure, but not backup respiratory rate, is essential to gain physiological and clinical benefits in this population when in a chronic stable condition.View original paper by Murphy and colleagues.

  6. The Effect of Equal Ratio Ventilation on Oxygenation, Respiratory Mechanics, and Cerebral Perfusion Pressure During Laparoscopy in the Trendelenburg Position.

    Science.gov (United States)

    Jo, Youn Yi; Kim, Ji Young; Chang, Young Jin; Lee, Sehwan; Kwak, Hyun Jeong

    2016-06-01

    The aim of this study was to investigate the effects of equal ratio ventilation (ERV) on oxygenation, respiratory mechanics, and the cerebral perfusion pressure during pneumoperitoneum in the Trendelenburg position. Thirty patients undergoing laparoscopic low anterior resection (25 to 65 y) were enrolled. Mechanical ventilator was set to volume-controlled mode at an inspiratory to expiratory (I:E) ratio of 1:2 with a tidal volume of 8 mL/kg of ideal body weight with a 5 cm H2O positive end-expiratory pressure. Twenty minutes after pneumoperitoneum in the Trendelenburg position, the I:E ratio was changed to 1:1 for 20 minutes and then restored to 1:2. No significant changes in arterial oxygen tension and respiratory compliance after adopting ERV. Mean arterial pressure and cerebral perfusion pressure decreased significantly over time after adopting the Trendelenburg position during pneumoperitoneum (P=0.014 and 0.005, respectively). In conclusion, there was no improvement in oxygenation or respiratory mechanics with ERV.

  7. Volume-Targeted Versus Pressure-Targeted Noninvasive Ventilation in Patients With Chest-Wall Deformity : A Pilot Study

    NARCIS (Netherlands)

    Struik, Fransien M.; Duiverman, Marieke L.; Meijer, Petra M.; Nieuwenhuis, Jellie A.; Kerstjens, Huib A. M.; Wijkstra, Peter J.

    2011-01-01

    BACKGROUND: Long-term noninvasive ventilation (NIV) is an effective treatment for patients with chronic respiratory failure due to chest-wall deformity, but it is unknown if the time required for the patient to adjust to long-term NIV depends on whether the NIV is volume-targeted or

  8. Recent advances in mechanical ventilation in patients with acute respiratory distress syndrome

    Directory of Open Access Journals (Sweden)

    Nuttapol Rittayamai

    2015-03-01

    Full Text Available Acute respiratory distress syndrome (ARDS is characterised by different degrees of severity and different stages. Understanding these differences can help to better adapt the ventilatory settings to protect the lung from ventilator-induced lung injury by reducing hyperinflation or keeping the lung open when it is possible. The same therapies may be useful and beneficial in certain forms of ARDS, and risky or harmful at other stages: this includes high positive end-expiratory pressure, allowance of spontaneous breathing activity or use of noninvasive ventilation. The severity of the disease is the primary indicator to individualise treatment. Monitoring tools such as oesophageal pressure or lung volume measurements may also help to set the ventilator. At an earlier stage, an adequate lung protective strategy may also help to prevent the development of ARDS.

  9. Nebulized heparin is associated with fewer days of mechanical ventilation in critically ill patients: a randomized controlled trial

    National Research Council Canada - National Science Library

    Dixon, Barry; Schultz, Marcus J; Smith, Roger; Fink, James B; Santamaria, John D; Campbell, Duncan J

    2010-01-01

    .... Heparin may reduce pulmonary inflammation and fibrin deposition. We therefore assessed whether nebulized heparin improved lung function in patients expected to require prolonged mechanical ventilation...

  10. [Analysis on risk factors of endotracheal cuff under inflation in mechanically ventilated patients].

    Science.gov (United States)

    Fu, You; Xi, Xiuming

    2014-12-01

    To investigate the prevalent condition of endotracheal cuff pressure and risk factors for under inflation. A prospective cohort study was conducted. Patients admitted to the Department of Critical Care Medicine of Fuxing Hospital Affiliated to Capital Medical University, who were intubated with a high-volume low-pressure endotracheal tube, and had undergone mechanical ventilation for at least 48 hours, were enrolled. The endotracheal cuff pressure was determined every 8 hours by a manual manometer connected to the distal edge of the valve cuff at 07 : 00, 15 : 00, and 23 : 00. Measurement of the endotracheal cuff pressure was continued until the extubation of endotracheal or tracheostomy tube, or death of the patient. According to the incidence of under inflation of endotracheal cuff, patients were divided into the incidence of under inflation lower than 25% group (lower low cuff pressure group) and higher than 25% group (higher low cuff pressure group). The possible influencing factors were evaluated in the two groups, including body mass index (BMI), size of endotracheal tube, duration of intubation, use of sedative or analgesic, number of leaving from intensive care unit (ICU), the number of turning over the patients, and aspiration of sputum. Logistic regression analysis was used to determine risk factors for under-inflation of the endotracheal cuff. During the study period, 53 patients were enrolled. There were 812 measurements, and 46.3% of them was abnormal, and 204 times (25.1%) of under inflation of endotracheal cuff were found. There were 24 patients (45.3%) in whom the incidence of under inflation rate was higher than 25%. The average of under inflation was 7 (4, 10) times. Compared with the group with lower rate of low cuff pressure, a longer time for intubation was found in group with higher rate of low cuff pressure [hours: 162 (113, 225) vs. 118 (97, 168), Z=-2.034, P=0.042]. There were no differences between the two groups in other factors

  11. Music preferences of mechanically ventilated patients participating in a randomized controlled trial.

    Science.gov (United States)

    Heiderscheit, Annie; Breckenridge, Stephanie J; Chlan, Linda L; Savik, Kay

    2014-01-01

    Mechanical ventilation (MV) is a life-saving measure and supportive modality utilized to treat patients experiencing respiratory failure. Patients experience pain, discomfort, and anxiety as a result of being mechanically ventilated. Music listening is a non-pharmacological intervention used to manage these psychophysiological symptoms associated with mechanical ventilation. The purpose of this secondary analysis was to examine music preferences of 107 MV patients enrolled in a randomized clinical trial that implemented a patient-directed music listening protocol to help manage the psychophysiological symptom of anxiety. Music data presented includes the music genres and instrumentation patients identified as their preferred music. Genres preferred include: classical, jazz, rock, country, and oldies. Instrumentation preferred include: piano, voice, guitar, music with nature sounds, and orchestral music. Analysis of three patients' preferred music received throughout the course of the study is illustrated to demonstrate the complexity of assessing MV patients and the need for an ongoing assessment process.

  12. Localized persistent pulmonary interstitial emphysema in a preterm infant in the absence of mechanical ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Berk, David R. [Stanford University School of Medicine, Division of Pediatric Radiology, CA (United States); Lucile Packard Children' s Hospital, Stanford, CA (United States); Varich, Laura J. [Stanford University School of Medicine, Division of Pediatric Radiology, CA (United States); Stanford University School of Medicine, Department of Radiology, CA (United States); Lucile Packard Children' s Hospital, Stanford, CA (United States)

    2005-12-01

    Localized persistent pulmonary interstitial emphysema has rarely been reported in preterm infants in the absence of utilization of mechanical ventilation or continuous positive airway pressure. The relative rarity of this condition might preclude rendering of the correct diagnosis, making patients susceptible to unnecessary surgery and increased morbidity and mortality associated with such intervention. We present a preterm infant who developed respiratory distress and radiographic findings of pulmonary interstitial emphysema on the first day after birth, prior to receiving continuous positive airway pressure or mechanical ventilation. It is important for radiologists to consider localized persistent pulmonary interstitial emphysema in the differential diagnosis of cystic lung lesions in preterm infants, even in the absence of mechanical ventilation. In cases where there is uncertainty, CT imaging can be useful in making the correct diagnosis. (orig.)

  13. Univariate Risk Factors for Prolonged Mechanical Ventilation in Patients Undergoing Prosthetic Heart Valves Replacement Surgery

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Data from 736 patients undergoing prosthetic heart valve replacement surgery and concomitant surgery (combined surgery) from January 1998 to January 2004 at Union Hospital were retrospectively reviewed. Univariate logistic regression analyses were conducted to identify risk factors for prolonged mechanical ventilation. The results showed that prolonged cardiopulmonary bypass duration, prolonged aortic cross clamp time and low ejection fraction less than 50 percent (50 %)were found to be independent predictors for prolonged mechanical ventilation. Meanwhile age,weight, and preoperative hospital stay (days) were not found to be associated with prolonged mechanical ventilation. It was concluded that, for age and weight, this might be due to the lower number of old age patients (70 years and above) included in our study and genetic body structure of majority Chinese population that favor them to be in normal weight, respectively.

  14. Cytomegalovirus and herpes simplex virus effect on the prognosis of mechanically ventilated patients suspected to have ventilator-associated pneumonia.

    Science.gov (United States)

    Coisel, Yannael; Bousbia, Sabri; Forel, Jean-Marie; Hraiech, Sami; Lascola, Bernard; Roch, Antoine; Zandotti, Christine; Million, Matthieu; Jaber, Samir; Raoult, Didier; Papazian, Laurent

    2012-01-01

    Cytomegalovirus (CMV) and herpes simplex virus (HSV) are common viruses that can affect critically ill patients who are not immunocompromised. The aim of this study was to determine whether the identification of CMV and/or HSV in mechanically ventilated critically ill patients suspected of having pneumonia was associated with an increased mortality. Prospective epidemiological study. Medical intensive care unit of a tertiary medical center. Ninety-three patients with suspected pneumonia. Patients with suspected pneumonia had bronchoalveolar lavage and blood samples taken to confirm the diagnosis. Antigenemia was used to detect CMV in the blood. Bronchoalveolar lavage samples were submitted to testing using quantitative real-time Polymerase Chain Reaction. We identified 22 patients with a CMV infection, 26 patients with an HSV infection and 45 patients without CMV or HSV infection (control group). Mortality at day 60 was higher in patients with a CMV infection than in patients from the control group (55% vs. 20%, P<0.01). Mortality at day 60 was not significantly increased in the group with HSV infection. Duration of ICU stay and ICU mortality were significantly higher in patients with CMV infections when compared to patients from the control group, whereas ventilator free days were significantly lower in patients with CMV infections when compared to patients from the control group. In critically ill patients, a CMV infection is associated with an increased mortality. Further interventional studies are needed to evaluate whether treatment could improve the prognosis.

  15. Effect of methacholine on peripheral lung mechanics and ventilation heterogeneity in asthma.

    Science.gov (United States)

    Downie, Sue R; Salome, Cheryl M; Verbanck, Sylvia; Thompson, Bruce R; Berend, Norbert; King, Gregory G

    2013-03-15

    The forced oscillation technique (FOT) and multiple-breath nitrogen washout (MBNW) are noninvasive tests that are potentially sensitive to peripheral airways, with MBNW indexes being especially sensitive to heterogeneous changes in ventilation. The objective was to study methacholine-induced changes in the lung periphery of asthmatic patients and determine how changes in FOT variables of respiratory system reactance (Xrs) and resistance (Rrs) and frequency dependence of resistance (Rrs5-Rrs19) can be linked to changes in ventilation heterogeneity. The contributions of air trapping and airway closure, as extreme forms of heterogeneity, were also investigated. Xrs5, Rrs5, Rrs19, Rrs5-Rrs19, and inspiratory capacity (IC) were calculated from the FOT. Ventilation heterogeneity in acinar and conducting airways, and trapped gas (percent volume of trapped gas at functional residual capacity/vital capacity), were calculated from the MBNW. Measurements were repeated following methacholine. Methacholine-induced airway closure (percent change in forced vital capacity) and hyperinflation (change in IC) were also recorded. In 40 mild to moderate asthmatic patients, increase in Xrs5 after methacholine was predicted by increases in ventilation heterogeneity in acinar airways and forced vital capacity (r(2) = 0.37, P ventilation heterogeneity in conducting airway increase or IC decrease. Increases in Rrs5 and Rrs5-Rrs19 after methacholine were not correlated with increases in ventilation heterogeneity, trapped gas, hyperinflation, or airway closure. Increased reactance in asthmatic patients after methacholine was indicative of heterogeneous changes in the lung periphery and airway closure. By contrast, increases in resistance and frequency dependence of resistance were not related to ventilation heterogeneity or airway closure and were more indicative of changes in central airway caliber than of heterogeneity.

  16. Enhancing rehabilitation of mechanically ventilated patients in the intensive care unit: a quality improvement project.

    Science.gov (United States)

    McWilliams, David; Weblin, Jonathan; Atkins, Gemma; Bion, Julian; Williams, Jenny; Elliott, Catherine; Whitehouse, Tony; Snelson, Catherine

    2015-02-01

    Prolonged periods of mechanical ventilation are associated with significant physical and psychosocial adverse effects. Despite increasing evidence supporting early rehabilitation strategies, uptake and delivery of such interventions in Europe have been variable. The objective of this study was to evaluate the impact of an early and enhanced rehabilitation program for mechanically ventilated patients in a large tertiary referral, mixed-population intensive care unit (ICU). A new supportive rehabilitation team was created within the ICU in April 2012, with a focus on promoting early and enhanced rehabilitation for patients at high risk for prolonged ICU and hospital stays. Baseline data on all patients invasively ventilated for at least 5 days in the previous 12 months (n = 290) were compared with all patients ventilated for at least 5 days in the 12 months after the introduction of the rehabilitation team (n = 292). The main outcome measures were mobility level at ICU discharge (assessed via the Manchester Mobility Score), mean ICU, and post-ICU length of stay (LOS), ventilator days, and in-hospital mortality. The introduction of the ICU rehabilitation team was associated with a significant increase in mobility at ICU discharge, and this was associated with a significant reduction in ICU LOS (16.9 vs 14.4 days, P = .007), ventilator days (11.7 vs 9.3 days, P rehabilitation within this European ICU improved levels of mobility at critical care discharge, and this was associated with reduced ICU and hospital LOS and reduced days of mechanical ventilation. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Multicenter Evaluation of a Novel Surveillance Paradigm for Complications of Mechanical Ventilation

    Science.gov (United States)

    Klompas, Michael; Khan, Yosef; Kleinman, Kenneth; Evans, R. Scott; Lloyd, James F.; Stevenson, Kurt; Samore, Matthew; Platt, Richard

    2011-01-01

    Background Ventilator-associated pneumonia (VAP) surveillance is time consuming, subjective, inaccurate, and inconsistently predicts outcomes. Shifting surveillance from pneumonia in particular to complications in general might circumvent the VAP definition's subjectivity and inaccuracy, facilitate electronic assessment, make interfacility comparisons more meaningful, and encourage broader prevention strategies. We therefore evaluated a novel surveillance paradigm for ventilator-associated complications (VAC) defined by sustained increases in patients' ventilator settings after a period of stable or decreasing support. Methods We assessed 600 mechanically ventilated medical and surgical patients from three hospitals. Each hospital contributed 100 randomly selected patients ventilated 2–7 days and 100 patients ventilated >7 days. All patients were independently assessed for VAP and for VAC. We compared incidence-density, duration of mechanical ventilation, intensive care and hospital lengths of stay, hospital mortality, and time required for surveillance for VAP and for VAC. A subset of patients with VAP and VAC were independently reviewed by a physician to determine possible etiology. Results Of 597 evaluable patients, 9.3% had VAP (8.8 per 1,000 ventilator days) and 23% had VAC (21.2 per 1,000 ventilator days). Compared to matched controls, both VAP and VAC prolonged days to extubation (5.8, 95% CI 4.2–8.0 and 6.0, 95% CI 5.1–7.1 respectively), days to intensive care discharge (5.7, 95% CI 4.2–7.7 and 5.0, 95% CI 4.1–5.9), and days to hospital discharge (4.7, 95% CI 2.6–7.5 and 3.0, 95% CI 2.1–4.0). VAC was associated with increased mortality (OR 2.0, 95% CI 1.3–3.2) but VAP was not (OR 1.1, 95% CI 0.5–2.4). VAC assessment was faster (mean 1.8 versus 39 minutes per patient). Both VAP and VAC events were predominantly attributable to pneumonia, pulmonary edema, ARDS, and atelectasis. Conclusions Screening ventilator settings for VAC captures a

  18. Manual ventilation and open suction procedures contribute to negative pressures in a mechanical lung model

    Science.gov (United States)

    Nakstad, Espen Rostrup; Opdahl, Helge; Heyerdahl, Fridtjof; Borchsenius, Fredrik; Skjønsberg, Ole Henning

    2017-01-01

    Introduction Removal of pulmonary secretions in mechanically ventilated patients usually requires suction with closed catheter systems or flexible bronchoscopes. Manual ventilation is occasionally performed during such procedures if clinicians suspect inadequate ventilation. Suctioning can also be performed with the ventilator entirely disconnected from the endotracheal tube (ETT). The aim of this study was to investigate if these two procedures generate negative airway pressures, which may contribute to atelectasis. Methods The effects of device insertion and suctioning in ETTs were examined in a mechanical lung model with a pressure transducer inserted distal to ETTs of 9 mm, 8 mm and 7 mm internal diameter (ID). A 16 Fr bronchoscope and 12, 14 and 16 Fr suction catheters were used at two different vacuum levels during manual ventilation and with the ETTs disconnected. Results During manual ventilation with ETTs of 9 mm, 8 mm and 7 mm ID, and bronchoscopic suctioning at moderate suction level, peak pressure (PPEAK) dropped from 23, 22 and 24.5 cm H2O to 16, 16 and 15 cm H2O, respectively. Maximum suction reduced PPEAK to 20, 17 and 11 cm H2O, respectively, and the end-expiratory pressure fell from 5, 5.5 and 4.5 cm H2O to –2, –6 and –17 cm H2O. Suctioning through disconnected ETTs (open suction procedure) gave negative model airway pressures throughout the duration of the procedures. Conclusions Manual ventilation and open suction procedures induce negative end-expiratory pressure during endotracheal suctioning, which may have clinical implications in patients who need high PEEP (positive end-expiratory pressure). PMID:28725445

  19. Role of noninvasive ventilation in weaning from mechanical ventilation in patients of chronic obstructive pulmonary disease: An Indian experience

    Directory of Open Access Journals (Sweden)

    Prasad Shiva

    2009-01-01

    Full Text Available Background: Endotracheal intubation and mechanical ventilation (MV are often needed in patients of chronic obstructive pulmonary disease (COPD with acute hypercapnic respiratory failure. The rate of weaning failure is high and prolonged MV increases intubation associated complications. Objective: To evaluate the role of Noninvasive ventilation (NIV in weaning patients of chronic obstructive pulmonary disease (COPD from MV, after T piece trial failure. Design: A prospective, randomized, controlled study was conducted in a tertiary care centre. 30 patients of acute exacerbation of COPD with acute on chronic hypercapnic respiratory failure, who were mechanically ventilated, were included in the study A T-piece weaning trial was attempted once the patients achieved satisfactory clinical and biochemical parameters. After T-piece failure, defined as pH < 7.35, PaCO 2 > 50 mmHg, PaO 2 < 50 mmHg, HR> 100/min, RR> 35, patients were randomized to receive either NIV or PSV. Results: Demography, severity of disease and clinical profiles were similar in both groups. No significant difference between the two groups in duration of MV (6.20 ± 5.20 days vs. 7.47 ± 6.38 days, P > 0.05, duration of weaning (35.17 ± 16.98 and 47.05 ± 20.98 hours, P > 0.05 or duration of ICU stay (8.47 ± 4.79 and 10.80 ± 5.28 days, P > 0.05 in Gp I and Gp II, respectively. Five patients developed VAP in the PSV group, where as only one patient had pneumonia in the NIV group. Lesser number of deaths in the NIV group at discharge from ICU (3 vs. 5 patients, respectively and at 30 days (5 vs. 9 patients, respectively, it did not achieve statistical significance (P > 0.05. Conclusion: NIV is as useful as PSV in weaning and can be better in weaning failure especially in COPD for earlier weaning, decrease ICU stay, complications and mortality.

  20. Cerebral Arterial Air Embolism Associated with Mechanical Ventilation and Deep Tracheal Aspiration

    Directory of Open Access Journals (Sweden)

    S. Gursoy

    2012-01-01

    Full Text Available Arterial air embolism associated with pulmonary barotrauma has been considered a rare but a well-known complication of mechanical ventilation. A 65-year-old man, who had subarachnoid hemorrhage with Glasgow coma scale of 8, was admitted to intensive care unit and ventilated with the help of mechanical ventilator. Due to the excessive secretions, deep tracheal aspirations were made frequently. GCS decreased from 8–10 to 4-5, and the patient was reevaluated with cranial CT scan. In CT scan, air embolism was detected in the cerebral arteries. The patient deteriorated and spontaneous respiratory activity lost just after the CT investigation. Thirty minutes later cardiac arrest appeared. Despite the resuscitation, the patient died. We suggest that pneumonia and frequent tracheal aspirations are predisposing factors for cerebral vascular air embolism.

  1. Neonatal total liquid ventilation: is low-frequency forced oscillation technique suitable for respiratory mechanics assessment?

    Science.gov (United States)

    Bossé, Dominick; Beaulieu, Alexandre; Avoine, Olivier; Micheau, Philippe; Praud, Jean-Paul; Walti, Hervé

    2010-08-01

    This study aimed to implement low-frequency forced oscillation technique (LFFOT) in neonatal total liquid ventilation (TLV) and to provide the first insight into respiratory impedance under this new modality of ventilation. Thirteen newborn lambs, weighing 2.5 + or - 0.4 kg (mean + or - SD), were premedicated, intubated, anesthetized, and then placed under TLV using a specially design liquid ventilator and a perfluorocarbon. The respiratory mechanics measurements protocol was started immediately after TLV initiation. Three blocks of measurements were first performed: one during initial respiratory system adaptation to TLV, followed by two other series during steady-state conditions. Lambs were then divided into two groups before undergoing another three blocks of measurements: the first group received a 10-min intravenous infusion of salbutamol (1.5 microg x kg(-1) x min(-1)) after continuous infusion of methacholine (9 microg x kg(-1) x min(-1)), while the second group of lambs was chest strapped. Respiratory impedance was measured using serial single-frequency tests at frequencies ranging between 0.05 and 2 Hz and then fitted with a constant-phase model. Harmonic test signals of 0.2 Hz were also launched every 10 min throughout the measurement protocol. Airway resistance and inertance were starkly increased in TLV compared with gas ventilation, with a resonant frequency ventilation. We show that LFFOT is an effective tool to track respiratory mechanics under TLV.

  2. Modifiable risk factors for mechanical ventilator-associated pneumonia in intensive care

    Directory of Open Access Journals (Sweden)

    Raquel de Mendonça Nepomuceno

    2014-06-01

    Full Text Available Backgound and Objectives: Ventilator-associated pneumonia is a pulmonary infection that occurs 48 to 72 hours after endotracheal intubation and institution of mechanical ventilation, being considered one of the most feared adverse effects of intensive care therapy. Its incidence affects 10-30% of patients as an important cause of morbidity and mortality, of which mortality rate can exceed 25%. Modifiable risk factors are seen as crucial in decision-making for its treatment and prevention. Thus, the modifiable risk factors for pneumonia associated with invasive mechanical ventilation in patients admitted to the intensive care unit were described. Methods: This is a literature review carried out at Lilacs, SciELO, MEDLINE and Bdenf databases, to collect and summarize publications and subsequently, critically evaluate the risk factors for ventilator-associated pneumonia. Results: The inappropriate or indiscriminate use of antibiotics, lack of knowledge about the microbiota of the ICU and non compliance of the team regarding preventive measures predominated. Conclusion: Professionals must be made aware of the identified risk factors in order to carry out direct actions with short-term impact in the prevention and effective control of ventilator-associated pneumonia.

  3. Inspiratory muscle training is ineffective in mechanically ventilated critically ill patients

    Directory of Open Access Journals (Sweden)

    Caruso Pedro

    2005-01-01

    Full Text Available PURPOSE: Invasive mechanical ventilation is associated with complications, and its abbreviation is desirable. The imbalance between increased workload, decreased inspiratory muscle strength and endurance is an important determinant of ventilator dependence. Low endurance may be present due to respiratory muscle atrophy, critical illness, or steroid use. Specific inspiratory muscle training may increase or preserve endurance. The objective of the study was to test the hypothesis that inspiratory muscle training from the beginning of mechanical ventilation would abbreviate the weaning duration and decrease reintubation rate. As a secondary objective, we described the evolution of inspiratory muscle strength with and without inspiratory muscle training. METHODS: Prospective, randomized clinical trial in an adult clinical-surgical intensive care unit. Twelve patients trained the inspiratory muscles twice a day, and 13 patients did not (control. Training was performed adjusting the sensitivity of the ventilator based on the maximal inspiratory pressure. Patients underwent daily surveillance of the maximal inspiratory pressure. RESULTS: The weaning duration (31 ± 22 hr, control and 23 ± 11 hr, training group; P = .24 and reintubation rate (5 control and 3 training group; P = .39 were not statistically different. The maximal inspiratory pressure of the control group showed a trend toward a modest increase. In contrast, the training group showed a small decrease (P = .34. CONCLUSIONS: In acute critically ill patients, inspiratory muscle training from the beginning of mechanical ventilation neither abbreviated the weaning duration, nor decreased the reintubation rate. Inspiratory muscle strength tended to stay constant, along the mechanical ventilation, with or without this specific inspiratory muscle training.

  4. Intra-Abdominal Hypertension and Gastrointestinal Symptoms in Mechanically Ventilated Patients

    Directory of Open Access Journals (Sweden)

    Annika Reintam Blaser

    2011-01-01

    Full Text Available Background. We aimed to describe the incidence of intra-abdominal hypertension (IAH and gastrointestinal (GI symptoms and related outcome in mechanically ventilated (MV patients. Methods. Intra-abdominal pressure (IAP and gastric residual volumes were measured at least twice daily. IAH was defined as a mean daily value of IAP≥12 mmHg. Results. 398 patients were monitored for all together 2987 days. GI symptom(s occurred in 80.2% patients. 152 (38.2% patients developed IAH. Majority (93.4% of patients with IAH had GI symptoms. The more severe IAH was associated with the higher number of concomitant GI symptoms (P<.001. 142 (35.7% patients developed both IAH and at least one GI symptom at any time in ICU, and in 77 patients they occurred simultaneously on the same day. This subgroup had the highest ICU mortality (21.8%. In contrast, the small group of patients presenting only IAH, but not GI symptoms (10 patients, had no lethal outcome. Three patients (4.4% died without showing either IAH or GI symptoms. Conclusions. GI symptoms and IAH often, but not always, occur together. The patients having IAH solely without developing GI symptoms have rather good outcome.

  5. Fluid mechanics of ventilation system generated by buoyancy and momentum sources and experiments research

    Institute of Scientific and Technical Information of China (English)

    WANG Xin; HUANG Chen; FU Yu-ying; CAO Wei-wu

    2010-01-01

    This paper presents fluid mechanics of ventilation system formed by the momentum source and the buoyancy source,which investigates inter-action between the plume and the non-isothermal air jet since buoyancy source is produced by the plume and momentum source is generated by the air jet,respectively.The interaction is discussed by a mathematical model,an idealized situation of the plume rising from a point heat source of buoyancy alone-in particular the initial momentum flux at the source is zero.Furthermore,the paper discusses the effects of the parameters such as strength of source,air-flow volume and air-flow velocity used in the mathematical-physical model.Considering the effect of the plume generated by the indoor heat source,one expression of trajectory of the non-isothermal air jet produced by jet diffuser is deduced.And field-experiment has also been carried out to illustrate the effect on flowing-action of the air jet and validate the theoretical work.It can be concluded that the heat sources do have effect on the flowing-action of the air jet,and the effect mainly depends on the interaction produced by the plume and the air jet.The results show that the thermal buoyant effect of plumes on the air jet should be taken into account if the indoor heat sources are large enough.Numerical simulation is conducted and coincides with the experimental results as well.

  6. Promoting effective communication for patients receiving mechanical ventilation.

    Science.gov (United States)

    Grossbach, Irene; Stranberg, Sarah; Chlan, Linda

    2011-06-01

    Communicating effectively with ventilator-dependent patients is essential so that various basic physiological and psychological needs can be conveyed and decisions, wishes, and desires about the plan of care and end-of-life decision making can be expressed. Numerous methods can be used to communicate, including gestures, head nods, mouthing of words, writing, use of letter/picture boards and common words or phrases tailored to meet individualized patients' needs. High-tech alternative communication devices are available for more complex cases. Various options for patients with a tracheostomy tube include partial or total cuff deflation and use of a speaking valve. It is important for nurses to assess communication needs; identify appropriate alternative communication strategies; create a customized care plan with the patient, the patient's family, and other team members; ensure that the care plan is visible and accessible to all staff interacting with the patient; and continue to collaborate with colleagues from all disciplines to promote effective communication with nonvocal patients.

  7. Role of JNK signal transduction pathway in IL-8 and TNF-α secretion from alveolar macrophages induced by mechanical ventilation with large-tidal volume in rabbits%JNK信号转导通路在大潮气量机械通气诱发兔肺泡巨噬细胞分泌IL-8和TNF-α中的作用

    Institute of Scientific and Technical Information of China (English)

    童瑾; Juliy M.Perelman; Victor P.Kolosov

    2010-01-01

    Objective To investigate the role of c-Jun N-terminal kinase (JNK) signal transduction pathway in IL-8 and TNF-α secretion from alveolar macrophages induced by mechanical ventilation with large-tidal volume in rabbits. Methods Thirty male New Zealand white rabbits weighing 210-260 g were randomly divided into 330-40 bpm, PEEP 0), and SB203580 group (group S). The animals were anesthetized with iv pentobarbital sodium 40 mg/kg, traeheostomized and mechanically ventilated. Group C received no mechanical ventilation. The animals were mechanically ventilated for 3 days in group V. The animals were mechanically ventilated for 3 days and SB203580 (a specific JNK inhibitor) 6 mg/kg was injected via the ear vein every day during ventilation (the ventilation parameters were the same as those in group V). The animals were then sacrificed by exsanguination. The concentrations of IL-8 and TNF-α in bronchoalveolar lavage fluid (BALF) were determined by ELISA and the alveolar macrophages were collected. After the macrophages were cultured for 2 h in vitro, the expression of IL-8 mRNA and TNF-α mRNA was determined by RT-PCR. Results Compared with group C, the levels of IL-8 , TNF-α,IL-8 mRNA and TNF-α mRNA were significantly increased in group V (P<0.05). Compared with group V, the levels of TNF-α and TNF-α mRNA were significantly decreased ( P < 0.01 ), but no significant change was found in the levels of IL-8 and IL-8 mRNA in group S ( P > 0.05). Conclusion JNK signal transduction pathway plays an important role in TNF-α secretion from alveolar macrophages induced by mechanical ventilation with large-tidal volume in rabbits, but is not involved the secretion of TNF-α.%目的 评价c-Jun氨基末端激酶(JNK)在大潮气量机械通气诱发兔肺泡巨噬细胞分泌IL-8和TNF-α中的作用.方法 清洁级雄性新西兰白兔30只,体重210~260 g,随机分为3组(n=10):正常对照组(C组)不予任何刺激;机械通气组(V组)大潮气量机械通气3 d

  8. Monitoring of total positive end-expiratory pressure during mechanical ventilation by artificial neural networks.

    Science.gov (United States)

    Perchiazzi, Gaetano; Rylander, Christian; Pellegrini, Mariangela; Larsson, Anders; Hedenstierna, Göran

    2016-04-11

    Ventilation treatment of acute lung injury (ALI) requires the application of positive airway pressure at the end of expiration (PEEPapp) to avoid lung collapse. However, the total pressure exerted on the alveolar walls (PEEPtot) is the sum of PEEPapp and intrinsic PEEP (PEEPi), a hidden component. To measure PEEPtot, ventilation must be discontinued with an end-expiratory hold maneuver (EEHM). We hypothesized that artificial neural networks (ANN) could estimate the PEEPtot from flow and pressure tracings during ongoing mechanical ventilation. Ten pigs were mechanically ventilated, and the time constant of their respiratory system (τRS) was measured. We shortened their expiratory time (TE) according to multiples of τRS, obtaining different respiratory patterns (Rpat). Pressure (PAW) and flow (V'AW) at the airway opening during ongoing mechanical ventilation were simultaneously recorded, with and without the addition of external resistance. The last breath of each Rpat included an EEHM, which was used to compute the reference PEEPtot. The entire protocol was repeated after the induction of ALI with i.v. injection of oleic acid, and 382 tracings were obtained. The ANN had to extract the PEEPtot, from the tracings without an EEHM. ANN agreement with reference PEEPtot was assessed with the Bland-Altman method. Bland Altman analysis of estimation error by ANN showed -0.40 ± 2.84 (expressed as bias ± precision) and ±5.58 as limits of agreement (data expressed as cmH2O). The ANNs estimated the PEEPtot well at different levels of PEEPapp under dynamic conditions, opening up new possibilities in monitoring PEEPi in critically ill patients who require ventilator treatment.

  9. [Effect of propofol-based combined anesthesia on the development of adaptive mechanisms to the prolonged one-lung artificial ventilation].

    Science.gov (United States)

    Kurilova, O A; Vyzhigina, M A; Sandrikov, V A; Mizikov, V M; Kulagina, T Iu; Zhukova, S G; Parshin, V D

    2010-01-01

    The paper deals with the assessment of the adequacy and safety of multicomponent anesthesia based on propofol at lung surgery requiring one-lung ventilation (OLV) in patients with chronic respiratory diseases and with the evaluation of the effect of propofol on the development of adaptive mechanisms in various ventilation modalities in thoracic surgery. The pressor, resistive, and volume characteristics of pulmonary blood flow, systemic and intracardiac hemodynamics under artificial ventilation (AV) and OLV of a duration of up to 1.5 hours by a combination of pulmonal and transpulmonal thermodilution on a PiCCO plus device with a VOLEF attachment were compared. Multicomponent balanced anesthesia based on continuous graduated propofol infusion provides adequate protection of patients during thoracic operations, including those with concomitant respiratory abnormality.

  10. Mechanical ventilation alone, and in the presence sepsis, induces peripheral skeletal muscle catabolism in neonatal pigs

    Science.gov (United States)

    Reduced rates of skeletal muscle accretion are a prominent feature of the metabolic response to sepsis in infants and children. Septic neonates often require medical support with mechanical ventilation (MV). The combined effects of MV and sepsis in muscle have not been examined in neonates, in whom ...

  11. Mechanical ventilation induces myokine expression and catabolism in peripheral skeletal muscle in pigs

    Science.gov (United States)

    Endotoxin (LPS)-induced sepsis increases circulating cytokines which have been associated with skeletal muscle catabolism. During critical illness, it has been postulated that muscle wasting associated with mechanical ventilation (MV) occurs due to inactivity. We hypothesize that MV and sepsis promo...

  12. Mechanical ventilation and sepsis induce skeletal muscle catabolism in neonatal pigs

    Science.gov (United States)

    Reduced rates of skeletal muscle accretion are a prominent feature of the metabolic response to sepsis in infants and children. Septic neonates often require medical support with mechanical ventilation (MV). The combined effects of MV and sepsis in muscle have not been examined in neonates, in whom ...

  13. A protocol of no sedation for critically ill patients receiving mechanical ventilation

    DEFF Research Database (Denmark)

    Strøm, Thomas; Martinussen, Torben; Toft, Palle

    2010-01-01

    BACKGROUND: Standard treatment of critically ill patients undergoing mechanical ventilation is continuous sedation. Daily interruption of sedation has a beneficial effect, and in the general intesive care unit of Odense University Hospital, Denmark, standard practice is a protocol of no sedation....

  14. Using passive flux samplers to determine the ammonia emission from mechanically ventilated animal houses

    NARCIS (Netherlands)

    Mosquera Losada, J.; Ogink, N.W.M.; Scholtens, R.

    2003-01-01

    Ammonia emissions from animal houses are an important environmental issue in the Netherlands. The current technique in the Netherlands to measure ammonia emissions in mechanically ventilated animal houses is the chemiluminescence method (using a NOx monitor after conversion of NH3 to NO). During cam

  15. Unaffected contractility of diaphragm muscle fibers in humans on mechanical ventilation

    NARCIS (Netherlands)

    Hooijman, P.E.; Paul, M.A.; Stienen, G.J.; Beishuizen, A.; Hees, H.W.H. van; Singhal, S.; Bashir, M.; Budak, M.T.; Morgen, J.; Barsotti, R.J.; Levine, S.; Ottenheijm, C.A.C.

    2014-01-01

    Several studies have indicated that diaphragm dysfunction develops in patients on mechanical ventilation (MV). Here, we tested the hypothesis that the contractility of sarcomeres, i.e., the smallest contractile unit in muscle, is affected in humans on MV. To this end, we compared diaphragm muscle fi

  16. Mechanical ventilation enhances lung inflammation and caspase activity in a model of mouse pneumovirus infection

    NARCIS (Netherlands)

    R.A. Bem; J.B.M. van Woensel; A.P. Bos; A. Koski; A.W. Farnand; J.B. Domachowske; H.F. Rosenberg; T.R. Martin; G. Matute-Bello

    2009-01-01

    Severe infection with respiratory syncytial virus (RSV) in children can progress to respiratory distress and acute lung injury (ALI). Accumulating evidence suggests that mechanical ventilation (MV) is an important cofactor in the development of ALI by modulating the host immune responses to bacteria

  17. Initiation of home mechanical ventilation at home : A randomised controlled trial of efficacy, feasibility and costs

    NARCIS (Netherlands)

    Hazenberg, A; Kerstjens, H A M; Prins, S C L; Vermeulen, K M; Wijkstra, P J

    Introduction: Home mechanical ventilation (HMV) in the Netherlands is normally initiated in hospital, but this is expensive and often a burden for the patient. In this randomised controlled study we investigated whether initiation of HMV at home in patients with chronic respiratory failure is

  18. Initiation of home mechanical ventilation at home: A randomised controlled trial of efficacy, feasibility and costs

    NARCIS (Netherlands)

    Hazenberg, A.; Kerstjens, H.A.M.; Prins, S.C.L.; Vermeulen, K.M.; Wijkstra, P.J.

    2014-01-01

    Introduction Home mechanical ventilation (HMV) in the Netherlands is normally initiated in hospital, but this is expensive and often a burden for the patient. In this randomised controlled study we investigated whether initiation of HMV at home in patients with chronic respiratory failure is

  19. Initiation of home mechanical ventilation at home : A randomised controlled trial of efficacy, feasibility and costs

    NARCIS (Netherlands)

    Hazenberg, A; Kerstjens, H A M; Prins, S C L; Vermeulen, K M; Wijkstra, P J

    2014-01-01

    Introduction: Home mechanical ventilation (HMV) in the Netherlands is normally initiated in hospital, but this is expensive and often a burden for the patient. In this randomised controlled study we investigated whether initiation of HMV at home in patients with chronic respiratory failure is non-in

  20. Hypercapnic acidosis attenuates the pulmonary innate immune response in ventilated healthy mice.

    NARCIS (Netherlands)

    Halbertsma, F.J.; Vaneker, M.; Pickkers, P.; Snijdelaar, D.G.; Egmond, J. van; Scheffer, G.J.; Hoeven, J.G. van der

    2008-01-01

    BACKGROUND: Mechanical ventilation with small tidal volumes reduces the development of ventilator-induced lung injury and mortality, but may increase PaCO2. It is not clear whether the beneficial effect of a lung-protective strategy results from reduced ventilation pressures/tidal volumes or is medi

  1. Reflections on Pediatric High-Frequency Oscillatory Ventilation From a Physiologic Perspective

    NARCIS (Netherlands)

    Kneyber, Martin C. J.; van Heerde, Marc; Markhorst, Dick G.

    2012-01-01

    Mechanical ventilation using low tidal volumes has become universally accepted to prevent ventilator-induced lung injury. High-frequency oscillatory ventilation (HFOV) allows pulmonary gas exchange using very small tidal volume (1-2 mL/kg) with concomitant decreased risk of atelectrauma. However, it

  2. Non-invasive mechanic ventilation in treating acute respiratory failure

    Directory of Open Access Journals (Sweden)

    Federico Lari

    2009-12-01

    Full Text Available Non invasive ventilation (NIV in acute respiratory failure (ARF improve clinical parameters, arterial blood gases, decrease mortality and endo tracheal intubation (ETI rate also outside the intensive care units (ICUs. Objective of this study is to verify applicability of NIV in a general non respiratory medical ward. We enrolled 68 consecutive patients (Pts with Hypoxemic or Hyper capnic ARF: acute cardiogenic pulmonary edema (ACPE, exacerbation of chronic obstructive pulmonary disease (COPD, Pneu - monia, acute lung injury / acute respiratory distress syndrome (ALI/ARDS. NIV treatment was CPAP or PSV + PEEP. 12 Pts (18,5% met primary endpoint (NIV failure: 11 Pts (17% needed ETI (5ALI/ARDS p < 0,0001, 6COPD 16,6%, 1 Patient (1,5% died (Pneumonia. No Pts with ACPE failed (p = 0,0027. Secondary endpoints: significant improvement in Respiratory Rate (RR, Kelly Score, pH, PaCO2, PaO2 vs baseline. Median duration of treatment: 16:06 hours: COPD 18:54, ACPE 4:15. Mean length of hospitalisation: 8.66 days. No patients discontinued NIV, no side effects. Results are consistent with literature. Hypoxemic ARF related to ALI/ARDS and pneumonia show worst outcome: it is not advisable to manage these conditions with NIV outside the ICU. NIV for ARF due to COPD and ACPE is feasible, safe and effective in a general medical ward if selection of Pts, staff’s training and monitoring are appropriate. This should encourage the diffusion of NIV in this specific setting. According to strong evidences in literature, NIV should be considered a first line and standard treatment in these clinical conditions irrespective of the setting.

  3. Cytomegalovirus and herpes simplex virus effect on the prognosis of mechanically ventilated patients suspected to have ventilator-associated pneumonia.

    Directory of Open Access Journals (Sweden)

    Yannael Coisel

    Full Text Available OBJECTIVE: Cytomegalovirus (CMV and herpes simplex virus (HSV are common viruses that can affect critically ill patients who are not immunocompromised. The aim of this study was to determine whether the identification of CMV and/or HSV in mechanically ventilated critically ill patients suspected of having pneumonia was associated with an increased mortality. DESIGN: Prospective epidemiological study. SETTING: Medical intensive care unit of a tertiary medical center. PATIENTS: Ninety-three patients with suspected pneumonia. INTERVENTIONS: Patients with suspected pneumonia had bronchoalveolar lavage and blood samples taken to confirm the diagnosis. Antigenemia was used to detect CMV in the blood. Bronchoalveolar lavage samples were submitted to testing using quantitative real-time Polymerase Chain Reaction. MEASUREMENTS AND MAIN RESULTS: We identified 22 patients with a CMV infection, 26 patients with an HSV infection and 45 patients without CMV or HSV infection (control group. Mortality at day 60 was higher in patients with a CMV infection than in patients from the control group (55% vs. 20%, P<0.01. Mortality at day 60 was not significantly increased in the group with HSV infection. Duration of ICU stay and ICU mortality were significantly higher in patients with CMV infections when compared to patients from the control group, whereas ventilator free days were significantly lower in patients with CMV infections when compared to patients from the control group. CONCLUSIONS: In critically ill patients, a CMV infection is associated with an increased mortality. Further interventional studies are needed to evaluate whether treatment could improve the prognosis.

  4. Automated logging of inspiratory and expiratory non-synchronized breathing (ALIEN) for mechanical ventilation.

    Science.gov (United States)

    Chiew, Yeong Shiong; Pretty, Christopher G; Beatson, Alex; Glassenbury, Daniel; Major, Vincent; Corbett, Simon; Redmond, Daniel; Szlavecz, Akos; Shaw, Geoffrey M; Chase, J Geoffrey

    2015-01-01

    Asynchronous Events (AEs) during mechanical ventilation (MV) result in increased work of breathing and potential poor patient outcomes. Thus, it is important to automate AE detection. In this study, an AE detection method, Automated Logging of Inspiratory and Expiratory Non-synchronized breathing (ALIEN) was developed and compared between standard manual detection in 11 MV patients. A total of 5701 breaths were analyzed (median [IQR]: 500 [469-573] per patient). The Asynchrony Index (AI) was 51% [28-78]%. The AE detection yielded sensitivity of 90.3% and specificity of 88.3%. Automated AE detection methods can potentially provide clinicians with real-time information on patient-ventilator interaction.

  5. Evaluation of the predictors for duration of mechanical ventilation in respiratory intensive care unit

    Directory of Open Access Journals (Sweden)

    Hira H

    2006-01-01

    Full Text Available Background: Mechanical ventilation (MV is a life saving modality. Till no method is evolved to predict the duration of this treatment. This study is undertaken to evaluate the clinical and laboratory parameters at initiation and 48 hour of the patient being treated by mechanical ventilation; and correlate these parameters with the duration of MV required. Methods: It was prospective observational study conducted in the respiratory intensive care unit (RICU of a tertiary referral and teaching hospital. Thirty consecutive patients suffering from various medical diseases requiring MV were the participants. Clinical, laboratory, ventilatory parameters and six severity scores viz.; GCS, APACHE-II, SAPS, OSF, ALI/ARDS and Sepsis/Septic shock criteria of each patient, both at initiation and at 48 hour of MV were recorded. Correlation between various severity scores at initiation and at 48 hour of initiation with duration of mechanical ventilation was computed. Results: Based on the duration of mechanical ventilation required, the patients were divided in two groups. Those requiring mechanical ventilation < 7 days and> 7 days were designated Group I and Group II respectively. Three out of 6 severity scores (GCS, APACHE-II, SAPS recorded at 48 hour of MV showed statistically significant difference between the both groups with p value of 0.010, 0.009 and 0.006 respectively. Further stepwise logistic regression analysis showed that SAPS score at 48 hour of initiation was the best predictor of duration of MV. It was found that a cut off value of 15 for SAPS score at 48 hour might predict the duration of MV i.e. < 7days or> 7 days. Based on linear regression analysis a simple equation was formulated by putting the SAPS value at 48 hour, the value of Y was computed. If MV required was less than 7 days, the value of Y was more than - 0.172 and if need of mechanical ventilation was more than 7 days, Y was less than -0.1720. Conclusions: For patients requiring

  6. Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

    Energy Technology Data Exchange (ETDEWEB)

    Martin, E.

    2014-01-01

    The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

  7. Noninvasive mechanical ventilation in chronic obstructive pulmonary disease and in acute cardiogenic pulmonary edema.

    Science.gov (United States)

    Rialp Cervera, G; del Castillo Blanco, A; Pérez Aizcorreta, O; Parra Morais, L

    2014-03-01

    Noninvasive ventilation (NIV) with conventional therapy improves the outcome of patients with acute respiratory failure due to hypercapnic decompensation of chronic obstructive pulmonary disease (COPD) or acute cardiogenic pulmonary edema (ACPE). This review summarizes the main effects of NIV in these pathologies. In COPD, NIV improves gas exchange and symptoms, reducing the need for endotracheal intubation, hospital mortality and hospital stay compared with conventional oxygen therapy. NIV may also avoid reintubation and may decrease the length of invasive mechanical ventilation. In ACPE, NIV accelerates the remission of symptoms and the normalization of blood gas parameters, reduces the need for endotracheal intubation, and is associated with a trend towards lesser mortality, without increasing the incidence of myocardial infarction. The ventilation modality used in ACPE does not affect the patient prognosis.

  8. Trends in conventional mechanical ventilation and pulmonary graphics in the newborn

    Institute of Scientific and Technical Information of China (English)

    Kris C.Sekar

    2010-01-01

    @@ The optimal treatment for respiratory distress syndrome (RDS) in extremely low birth weight newborn infants now consists of surfactant therapy,ventilator support and aggressive nutritional support.1,2Introduction of surfactant therapy has significantly reduced both the mortality and morbidity in premature infants. However, despite all the preventive efforts the prematurity rate has increased in the United States. As a result of this trend the majority of the infants requiring mechanical ventilation in the current neonatal intensive care units are less than 1000 g. This has created new challenges in managing these infants respiratory distress to reduce mortality, morbidity and improve neurological outcome. Advances in optimal resuscitation, maintenance of thermal environment, early surfactant therapy, gentle ventilation, aggressive nutritional support, early treatment of patent ductus arteriosus, control of infection etc. have been adopted to reduce mortality and morbidity. However,despite all these advancements in neonatal care the incidence of bronchopulmonary dysplasia (BPD) has not decreased.3'4

  9. Dynamic Characteristics of Mechanical Ventilation System of Double Lungs with Bi-Level Positive Airway Pressure Model

    Directory of Open Access Journals (Sweden)

    Dongkai Shen

    2016-01-01

    Full Text Available In recent studies on the dynamic characteristics of ventilation system, it was considered that human had only one lung, and the coupling effect of double lungs on the air flow can not be illustrated, which has been in regard to be vital to life support of patients. In this article, to illustrate coupling effect of double lungs on flow dynamics of mechanical ventilation system, a mathematical model of a mechanical ventilation system, which consists of double lungs and a bi-level positive airway pressure (BIPAP controlled ventilator, was proposed. To verify the mathematical model, a prototype of BIPAP system with a double-lung simulators and a BIPAP ventilator was set up for experimental study. Lastly, the study on the influences of key parameters of BIPAP system on dynamic characteristics was carried out. The study can be referred to in the development of research on BIPAP ventilation treatment and real respiratory diagnostics.

  10. Comparison of efficacy of pressure-controlled ventilation and volume-controlled ventilation in children undergoing laparoscopic surgery%腹腔镜手术患儿压力控制通气和容量控制通气效果的比较

    Institute of Scientific and Technical Information of China (English)

    冯继峰; 郑剑秋; 周蜀克

    2014-01-01

    Objective To compare the efficacy of pressure-controlled ventilation and volume-controlled ventilation in children undergoing laparoscopic surgery.Methods Thirty ASA Ⅰ or Ⅱ children of both sexes,aged 12-36 months,weighing 9-15 kg,scheduled for laparoscopic surgery,were randomly divided into two groups (n =15 each):pressure-controlled ventilation group (group P) and volume-controlled ventilation group (group Ⅴ).After anesthesia was induced with propofol 2-4 mg/kg,vecuronium 0.1 mg/kg and fentanyl 2 μg/kg,the children received endotracheal intubation and mechanical ventilation.The maximum inspiratory pressure was adjusted to make the tidal volume (VT) achieve 12 ml/kg in group P and the VT was set at 12 ml/kg in group V.The end-tidal pressure of carbon dioxide (PET CO2) was controlled at 35-45 mm Hg.The mean arterial blood pressure (MAP),heart rate (HR),arterial carbpn dioxide tension (PaCO2),PETCO2,minute ventilation and peak airway pressure were recorded immediately after intubation (T0),immediately before skin incision (T1),after 30 minutes of pneumoperitoneum (T2) and 15 minutes after the end of pneumoperitoneum (T3).Arterial blood samples were taken at the same time points mentioned above for blood gas analysis.Dynamic lung compliance and the ratio of the physiological dead space to the tidal volume were calculated.Results Compared with group Ⅴ,PaCO2 and PET CO2 were significantly decreased and dynamic lung compliance was significantly increased at T1-2,and minute ventilation and peak airway pressure were significantly decreased at T0-3 in group P (P < 0.01).There was no significant difference in MAP,HR and the ratio of the physiological dead space to the tidal volume between the two groups (P > 0.05).Conclusion Compared with volume-controlled ventilation,pressure-controlled ventilation can better improve the ventilatory efficacy,is more beneficial to gas exchange and reduces the influence of pneumoperitoneum on respiratory function in children

  11. The influence of ventilation variables on the volume rate of airflow delivered to the face of long drivages

    Energy Technology Data Exchange (ETDEWEB)

    Onder, M.; Sarac, S.; Cevik, E. [Osmangazi University, Eskisehir (Turkey). Dept. of Mining Engineering

    2006-09-15

    Auxiliary ventilation is performed by carrying intake or return air in ducts. The complete elimination of air leakage from or into the ducting system is impossible due to duct quality and numerous joints in ducting system. The auxiliary ventilation systems for long drivages often require the use of multiple fans. There are many methods proposed for the analysis air flow problems in leaky ducts. In this study, a method known as 'series-parallel combination of the duct and leakage path' has been introduced and a computer program has been developed based on this method. In order to design the conditions of an auxiliary ventilated drivage, in situ measurement have been made in the Omerler underground coal mine (Turkey) and the related data necessary for this study was collected. The presently developed program was tested using these data, and it was found that the measured and calculated values are quite close. The effective operational parameters governing auxiliary ventilation have been investigated and the effects of these variables on the volume rate of air flow reaching long drivage face have been examined by using linear regression analysis. Finally, it was concluded that the increase of duct diameter has prime importance in achieving the adequate air flow to the face and that for the auxiliary fans considered in this study the selection of fan does not greatly affect the volume rate reaching the face in a long duct line.

  12. A Prognostic Model for One-year Mortality in Patients Requiring Prolonged Mechanical Ventilation

    Science.gov (United States)

    Carson, Shannon S.; Garrett, Joanne; Hanson, Laura C.; Lanier, Joyce; Govert, Joe; Brake, Mary C.; Landucci, Dante L.; Cox, Christopher E.; Carey, Timothy S.

    2009-01-01

    Objective A measure that identifies patients who are at high risk of mortality after prolonged ventilation will help physicians communicate prognosis to patients or surrogate decision-makers. Our objective was to develop and validate a prognostic model for 1-year mortality in patients ventilated for 21 days or more. Design Prospective cohort study. Setting University-based tertiary care hospital Patients 300 consecutive medical, surgical, and trauma patients requiring mechanical ventilation for at least 21 days were prospectively enrolled. Measurements and Main Results Predictive variables were measured on day 21 of ventilation for the first 200 patients and entered into logistic regression models with 1-year and 3-month mortality as outcomes. Final models were validated using data from 100 subsequent patients. One-year mortality was 51% in the development set and 58% in the validation set. Independent predictors of mortality included requirement for vasopressors, hemodialysis, platelet count ≤150 ×109/L, and age ≥50. Areas under the ROC curve for the development model and validation model were 0.82 (se 0.03) and 0.82 (se 0.05) respectively. The model had sensitivity of 0.42 (se 0.12) and specificity of 0.99 (se 0.01) for identifying patients who had ≥90% risk of death at 1 year. Observed mortality was highly consistent with both 3- and 12-month predicted mortality. These four predictive variables can be used in a simple prognostic score that clearly identifies low risk patients (no risk factors, 15% mortality) and high risk patients (3 or 4 risk factors, 97% mortality). Conclusions Simple clinical variables measured on day 21 of mechanical ventilation can identify patients at highest and lowest risk of death from prolonged ventilation. PMID:18552692

  13. Short-term effects of neuromuscular blockade on global and regional lung mechanics, oxygenation and ventilation in pediatric acute hypoxemic respiratory failure

    OpenAIRE

    Wilsterman, Marlon E. F.; de Jager, Pauline; Blokpoel, Robert; Frerichs, Inez; Dijkstra, Sandra K.; Albers, Marcel J. I. J.; Burgerhof, Johannes G.M.; Markhorst, Dick G; Kneyber, Martin C. J.

    2016-01-01

    Background Neuromuscular blockade (NMB) has been shown to improve outcome in acute respiratory distress syndrome (ARDS) in adults, challenging maintaining spontaneous breathing when there is severe lung injury. We tested in a prospective physiological study the hypothesis that continuous administration of NMB agents in mechanically ventilated children with severe acute hypoxemic respiratory failure (AHRF) improves the oxygenation index without a redistribution of tidal volume V T toward non-d...

  14. Energy Impacts of Envelope Tightening and Mechanical Ventilation for the U.S. Residential Sector

    Energy Technology Data Exchange (ETDEWEB)

    Logue, J. M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, M. H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, I. S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, B. C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-01-01

    Effective residential envelope air sealing reduces infiltration and associated energy costs for thermal conditioning, yet often creates a need for mechanical ventilation to protect indoor air quality. This study estimated the potential energy savings of implementing airtightness improvements or absolute standards along with mechanical ventilation throughout the U.S. housing stock. We used a physics-based modeling framework to simulate the impact of envelope tightening, providing mechanical ventilation as needed. There are 113 million homes in the US. We calculated the change in energy demand for each home in a nationally representative sample of 50,000 virtual homes developed from the 2009 Residential Energy Consumption Survey. Ventilation was provided as required by 2010 and proposed 2013 versions of ASHRAE Standard 62.2. Ensuring that all current homes comply with 62.2-2010 would increase residential site energy demand by 0.07 quads (0.07 exajoules (EJ)) annually. Improving airtightness of all homes at current average retrofit performance levels would decrease demand by 0.7 quads (0.74 EJ) annually and upgrading all homes to be as airtight as the top 10% of similar homes would double the savings, leading to roughly $22 billion in annual savings in energy bills. We also analyzed the potential benefits of bringing the entire stock to airtightness specifications of IECC 2012, Canada's R2000, and Passive House standards.

  15. "Not being able to talk was horrid": A descriptive, correlational study of communication during mechanical ventilation.

    Science.gov (United States)

    Guttormson, Jill L; Bremer, Karin Lindstrom; Jones, Rachel M

    2015-06-01

    The purpose of this study was to describe the patient experience of communication during mechanical ventilation. This descriptive study is a secondary analysis of data collected to study the relationship between sedation and the MV patients' recall of the ICU. Interviews, conducted after extubation, included the Intensive Care Experience Questionnaire. Data were analysed with Spearman correlation coefficients (rs) and content analysis. Participants were recruited from a medical-surgical intensive care unit in the Midwest United States. Participants (n = 31) with a mean age of 65 ± 11.9 were on the ventilator a median of 5 days. Inability to communicate needs was associated with helplessness (rs = .43). While perceived lack of information received was associated with not feeling in control (rs = 41) and helplessness (rs = 41). Ineffective communication impacted negatively on satisfaction with care. Participants expressed frustration with failed communication and a lack of information received. They believed receipt of information helped them cope and desired a better system of communication during mechanical ventilation. Communication effectiveness impacts patients' sense of safety and well-being during mechanical ventilation. Greater emphasis needs to be placed on the development and integration of communication strategies into critical care nursing practice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. From mechanical ventilation to intensive care medicine: a challenge for Bosnia and Herzegovina.

    Science.gov (United States)

    Thiéry, Guillaume; Kovacević, Pedja; Straus, Slavenka; Vidovic, Jadranka; Iglica, Amer; Festic, Emir; Gajic, Ognjen

    2009-10-01

    Intensive care medicine is a relatively new specialty, which was created in the 1950's, after invent of mechanical ventilation, which allowed caring for critically ill patients who otherwise would have died. First created for treating mechanically ventilated patients, ICUs extended their scope and care to all patients with life threatening conditions. Over the years, intensive care medicine developed further and became a truly multidisciplinary speciality, encompassing patients from various fields of medicine and involving specialists from a range of base specialties, with additional (subspecialty) training in intensive care medicine. In Bosnia and Herzegovina, the founding of the society of intensive care medicine in 2006, the introduction of non invasive ventilation in 2007, and opening of a multidisciplinary ICUs in Banja Luka and Sarajevo heralded a new age of intensive care medicine. The number of admissions, high severity scores and needs for mechanical ventilation during the first several months in the medical ICU in Banja Luka confirmed the need of these kinds of units in the country. In spite of still suboptimal personnel training, creation of ICUs in Bosnia and Herzegovina may serve as example for other developing countries in the region. However, in order to achieve modern ICU standards and follow European trends toward harmonisation of medicine, Bosnia and Herzegovina needs to take up this challenge by recognizing intensive care medicine as a distinctive specialty, by implementing a specific training program and by setting up multidisciplinary ICUs in acute care hospitals.

  17. The pressure drop across the endotracheal tube in mechanically ventilated pediatric patients.

    Science.gov (United States)

    Spaeth, Johannes; Steinmann, Daniel; Kaltofen, Heike; Guttmann, Josef; Schumann, Stefan

    2015-04-01

    During mechanical ventilation, the airway pressure (Paw) is usually monitored. However, Paw comprises the endotracheal tube (ETT)-related pressure drop (∆PETT ) and thus does not reflect the pressure in the patients' lungs. Therefore, monitoring of mechanical ventilation should be based on the tracheal pressure (Ptrach ). We systematically investigated potential factors influencing ∆PETT in pediatric ETTs. In this study, the flow-dependent pressure drop across pediatric ETTs from four manufacturers [2.0-4.5 mm inner diameter (ID)] was estimated in a physical model of the upper airways. Additionally, ∆PETT was examined with the ETTs shortened to 75% of their original length and at different curvatures. In nine healthy mechanically ventilated children (aged between 9 days and 29 months), Ptrach was compared to Paw . ∆PETT was nonlinearly flow dependent. Low IDs corresponded to high ∆PETT . Differences between ETTs from different manufacturers were identified. Shortening of the ETTs' length by 25% reduced ∆PETT on average by 14% of the value at original length. Ventilation frequency and tube curvature did not influence ∆PETT to a relevant extent. In the pediatric patients, the root mean square deviation between Paw and Ptrach was 2.3 cm H2O. Paw and Ptrach differ considerably (by ∆PETT ) during mechanical ventilation of pediatric patients. The ETTs' ID, tube length, and manufacturer type are significant factors for ∆PETT and should be taken into account when Paw is valuated. For this purpose, Ptrach can be continuously calculated with good precision by means of the Rohrer approximation. © 2014 John Wiley & Sons Ltd.

  18. Mechanical ventilation in Coffin-Lowry syndrome: a case report

    Science.gov (United States)

    de Moura, Edmilson Bastos; de Moura, Érica Leal Teixeira; Amorim, Fábio Ferreira; Oliveira, Vânia Maria

    2016-01-01

    We describe a 27-year-old patient with Coffin-Lowry syndrome with severe community pneumonia, septic shock and respiratory failure. We summarize both the mechanical ventilatory assistance and the hospitalization period in the intensive care unit. PMID:28099645

  19. The role of ventilation mode using a laryngeal mask airway during gynecological laparoscopy on lung mechanics, hemodynamic response and blood gas analysis.

    Science.gov (United States)

    Jarahzadeh, Mohammad Hossein; Halvaei, Iman; Rahimi-Bashar, Farshid; Behdad, Shekoufeh; Abbasizadeh Nasrabady, Rouhollah; Yasaei, Elahe

    2016-12-01

    There are two methods for ventilation in gynecological laparoscopy: volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV). To compare the lung mechanics, hemodynamic response and arterial blood gas analysis and gas exchange of two modes of VCV and PCV using laryngeal mask airway (LMA) at different time intervals. Sixty infertile women referred for diagnostic laparoscopy, based on ventilation mode, were randomly divided into two groups of VCV (tidal volume: 10 ml/kg) and PCV. In the PCV group, ventilation was initiated with a peak airway pressure (tidal volume: 10 ml/kg, upper limit: 35 cm H2O). In both groups, the arterial blood samples were taken in several time intervals (5, 10 and 15 min after LMA insertion) for blood gas evaluation. Also the lung mechanics parameters were continuously monitored and were recorded at different time intervals. There were no significant differences for patient's age, weight, height and BMI in two groups. The peak and plateau airway pressure were significantly higher in VCV group compared to PCV group 5 and 10 min after insertion of LMA. PaO2 was significantly higher after 10 and 15 min in VCV group compared to PCV group (p=0.005 and p=0.03, respectively). PaCO2 showed significant increase after 5 min in PCV group, but the differences were not significant after 10 and 15 min in two groups. The end tidal CO2 showed significant increase after 10 and 15 min in VCV compared to PCV group. Both VCV and PCV seem to be suitable for gynecological laparoscopy. However, airway pressures are significantly lower in PCV compared to VCV.

  20. Correlation between timing of tracheostomy and duration of mechanical ventilation in patients with potentially normal lungs admitted to intensive care unit

    Directory of Open Access Journals (Sweden)

    Mehrdad Masoudifar

    2012-01-01

    Conclusion: Our study with mentioned sample size could not show any relationship between timing of tracheostomy and duration of mechanical ventilation in patients under mechanical ventilation with good pulmonary function in ICU.

  1. Microbial composition and antibiotic resistance of biofilms recovered from endotracheal tubes of mechanically ventilated patients.

    Science.gov (United States)

    Vandecandelaere, Ilse; Coenye, Tom

    2015-01-01

    In critically ill patients, breathing is impaired and mechanical ventilation, using an endotracheal tube (ET) connected to a ventilator, is necessary. Although mechanical ventilation is a life-saving procedure, it is not without risk. Because of several reasons, a biofilm often forms at the distal end of the ET and this biofilm is a persistent source of bacteria which can infect the lungs, causing ventilator-associated pneumonia (VAP). There is a link between the microbial flora of ET biofilms and the microorganisms involved in the onset of VAP. Culture dependent and independent techniques were already used to identify the microbial flora of ET biofilms and also, the antibiotic resistance of microorganisms obtained from ET biofilms was determined. The ESKAPE pathogens play a dominant role in the onset of VAP and these organisms were frequently identified in ET biofilms. Also, antibiotic resistant microorganisms were frequently present in ET biofilms. Members of the normal oral flora were also identified in ET biofilms but it is thought that these organisms initiate ET biofilm formation and are not directly involved in the development of VAP.

  2. Novel method for conscious airway resistance and ventilation estimation in neonatal rodents using plethysmography and a mechanical lung.

    Science.gov (United States)

    Zhang, Boyang; McDonald, Fiona B; Cummings, Kevin J; Frappell, Peter B; Wilson, Richard J A

    2014-09-15

    In unrestrained whole body plethysmography, tidal volume is commonly determined using the barometric method, which assumes that temperature and humidity changes (the 'barometric component') are solely responsible for breathing-related chamber pressure fluctuations. However, in small animals chamber pressure is also influenced by a 'mechanical component' dependent on airway resistance and airflow. We devised a novel 'mechanical lung' capable of simulating neonatal mouse breathing in the absence of temperature or humidity changes. Using this device, we confirm that the chamber pressure fluctuations produced by breathing of neonatal mice are dominated by the mechanical component, precluding direct quantitative assessment of tidal volume. Recognizing the importance of airway resistance to the chamber pressure signal and the ability of our device to simulate neonatal breathing at different frequencies and tidal volumes, we invented a novel in vivo, non-invasive method for conscious airway resistance and ventilation estimation (CARVE) in neonatal rodents. This technique will allow evaluation of developmental, pathological and pharmaceutical effects on airway resistance.

  3. Mechanical Behaviour of Materials Volume II Fracture Mechanics and Damage

    CERN Document Server

    François, Dominique; Zaoui, André

    2013-01-01

    Designing new structural materials, extending lifetimes and guarding against fracture in service are among the preoccupations of engineers, and to deal with these they need to have command of the mechanics of material behaviour. This ought to reflect in the training of students. In this respect, the first volume of this work deals with elastic, elastoplastic, elastoviscoplastic and viscoelastic behaviours; this second volume continues with fracture mechanics and damage, and with contact mechanics, friction and wear. As in Volume I, the treatment links the active mechanisms on the microscopic scale and the laws of macroscopic behaviour. Chapter I is an introduction to the various damage phenomena. Chapter II gives the essential of fracture mechanics. Chapter III is devoted to brittle fracture, chapter IV to ductile fracture and chapter V to the brittle-ductile transition. Chapter VI is a survey of fatigue damage. Chapter VII is devoted to hydogen embrittlement and to environment assisted cracking, chapter VIII...

  4. Dependence of lung injury on inflation rate during low-volume ventilation in normal open-chest rabbits.

    Science.gov (United States)

    D'Angelo, Edgardo; Pecchiari, Matteo; Saetta, Marina; Balestro, Elisabetta; Milic-Emili, Joseph

    2004-07-01

    Lung mechanics and morphometry were assessed in two groups of nine normal open-chest rabbits mechanically ventilated (MV) for 3-4 h at zero end-expiratory pressure (ZEEP) with physiological tidal volumes (Vt; 11 ml/kg) and high (group A) or low (group B) inflation flow (44 and 6.1 ml x kg(-1) x s(-1), respectively). Relative to initial MV on positive end-expiratory pressure (PEEP; 2.3 cmH(2)O), MV on ZEEP increased quasi-static elastance and airway and viscoelastic resistance more in group A (+251, +393, and +225%, respectively) than in group B (+180, +247, and +183%, respectively), with no change in viscoelastic time constant. After restoration of PEEP, quasi-static elastance and viscoelastic resistance returned to control, whereas airway resistance, still relative to initial values, remained elevated more in group A (+86%) than in group B (+33%). In contrast, prolonged high-flow MV on PEEP had no effect on lung mechanics of seven open-chest rabbits (group C). Gas exchange on PEEP was equally preserved in all groups, and the lung wet-to-dry ratios were normal. Relative to group C, both groups A and B had an increased percentage of abnormal alveolar-bronchiolar attachments and number of polymorphonuclear leukocytes in alveolar septa, the latter being significantly larger in group A than in group B. Thus prolonged MV on ZEEP with cyclic opening-closing of peripheral airways causes alveolar-bronchiolar uncoupling and parenchymal inflammation with concurrent, persistent increase in airway resistance, which are worsened by high-inflation flow.

  5. Correlation between central venous pressure and peripheral venous pressure with passive leg raise in patients on mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Dharmendra Kumar

    2015-01-01

    Full Text Available Background: Central venous pressure (CVP assesses the volume status of patients. However, this technique is not without complications. We, therefore, measured peripheral venous pressure (PVP to see whether it can replace CVP. Aims: To evaluate the correlation and agreement between CVP and PVP after passive leg raise (PLR in critically ill patients on mechanical ventilation. Setting and Design: Prospective observational study in Intensive Care Unit. Methods: Fifty critically ill patients on mechanical ventilation were included in the study. CVP and PVP measurements were taken using a water column manometer. Measurements were taken in the supine position and subsequently after a PLR of 45°. Statistical Analysis: Pearson′s correlation and Bland-Altman′s analysis. Results: This study showed a fair correlation between CVP and PVP after a PLR of 45° (correlation coefficient, r = 0.479; P = 0.0004 when the CVP was 10 cmH 2 O. Bland-Altman analysis showed 95% limits of agreement to be −2.912-9.472. Conclusion: PVP can replace CVP for guiding fluid therapy in critically ill patients.

  6. Development of Localized Pulmonary Interstitial Emphysema in a Late Preterm Infant without Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    Pritish Bawa

    2014-01-01

    Full Text Available Pulmonary interstitial emphysema (PIE is not an uncommon finding in premature infants with respiratory distress who need respiratory support by mechanical ventilation. PIE has been reported in a few cases of neonates in whom either no treatment other than room air was given or they were given continuous positive end-expiratory pressure (CPAP support. We present a case of a premature neonate who presented with respiratory distress, in whom PIE and spontaneous pneumothorax (PTX developed while on CPAP therapy only. The patient was treated conservatively with subsequent resolution of the radiological findings and clinical improvement. No surgical intervention was required. It is important to know that PIE may develop independently of mechanical ventilation. We would like to add this case to the literature and describe the pertinent plain film and computed tomography (CT findings of this entity, the possible mechanism of development, and the differential diagnosis. A review of the literature is also provided.

  7. Development of Localized Pulmonary Interstitial Emphysema in a Late Preterm Infant without Mechanical Ventilation

    Science.gov (United States)

    Soontarapornchai, Kultida; Perenyi, Agnes; Amodio, John

    2014-01-01

    Pulmonary interstitial emphysema (PIE) is not an uncommon finding in premature infants with respiratory distress who need respiratory support by mechanical ventilation. PIE has been reported in a few cases of neonates in whom either no treatment other than room air was given or they were given continuous positive end-expiratory pressure (CPAP) support. We present a case of a premature neonate who presented with respiratory distress, in whom PIE and spontaneous pneumothorax (PTX) developed while on CPAP therapy only. The patient was treated conservatively with subsequent resolution of the radiological findings and clinical improvement. No surgical intervention was required. It is important to know that PIE may develop independently of mechanical ventilation. We would like to add this case to the literature and describe the pertinent plain film and computed tomography (CT) findings of this entity, the possible mechanism of development, and the differential diagnosis. A review of the literature is also provided. PMID:24744939

  8. Positive outcome of average volume-assured pressure support mode of a Respironics V60 Ventilator in acute exacerbation of chronic obstructive pulmonary disease: a case report

    Directory of Open Access Journals (Sweden)

    Okuda Miyuki

    2012-09-01

    Full Text Available Abstract Introduction We were able to treat a patient with acute exacerbation of chronic obstructive pulmonary disease who also suffered from sleep-disordered breathing by using the average volume-assured pressure support mode of a Respironics V60 Ventilator (Philips Respironics: United States. This allows a target tidal volume to be set based on automatic changes in inspiratory positive airway pressure. This removed the need to change the noninvasive positive pressure ventilation settings during the day and during sleep. The Respironics V60 Ventilator, in the average volume-assured pressure support mode, was attached to our patient and improved and stabilized his sleep-related hypoventilation by automatically adjusting force to within an acceptable range. Case presentation Our patient was a 74-year-old Japanese man who was hospitalized for treatment due to worsening of dyspnea and hypoxemia. He was diagnosed with acute exacerbation of chronic obstructive pulmonary disease and full-time biphasic positive airway pressure support ventilation was initiated. Our patient was temporarily provided with portable noninvasive positive pressure ventilation at night-time following an improvement in his condition, but his chronic obstructive pulmonary disease again worsened due to the recurrence of a respiratory infection. During the initial exacerbation, his tidal volume was significantly lower during sleep (378.9 ± 72.9mL than while awake (446.5 ± 63.3mL. A ventilator that allows ventilation to be maintained by automatically adjusting the inspiratory force to within an acceptable range was attached in average volume-assured pressure support mode, improving his sleep-related hypoventilation, which is often associated with the use of the Respironics V60 Ventilator. Polysomnography performed while our patient was on noninvasive positive pressure ventilation revealed obstructive sleep apnea syndrome (apnea-hypopnea index = 14, suggesting that his chronic

  9. Dead space reduction by Kolobow's endotracheal tube does not justify the waiving of volume monitoring in small, ventilated lungs.

    Science.gov (United States)

    Proquitté, Hans; Wendel, Rena; Roehr, Charles C; Wauer, Roland R; Schmalisch, Gerd

    2014-12-01

    In ventilated preterm infants the flow sensor contributes significantly to the total apparatus dead space, which may impair gas exchange. The aim of the study was to quantify to which extent a dead space reduced Kolobow tube (KB) without flow sensor improves the gas exchange compared with a conventional ventilator circuit with flow sensor [Babylog 8000 (BL)]. In a cross-over trial in 14 tracheotomized, surfactant-depleted (saline lavage) and mechanically ventilated newborn piglets (age space of BL and KB including the endotracheal tube were 3.0 and 1.34 mL. Despite a 50 % apparatus dead space reduction with KB compared to BL statistically significant improvements were only observed for body weights monitoring.

  10. Monitoring of intratidal lung mechanics: a Graphical User Interface for a model-based decision support system for PEEP-titration in mechanical ventilation.

    Science.gov (United States)

    Buehler, S; Lozano-Zahonero, S; Schumann, S; Guttmann, J

    2014-12-01

    In mechanical ventilation, a careful setting of the ventilation parameters in accordance with the current individual state of the lung is crucial to minimize ventilator induced lung injury. Positive end-expiratory pressure (PEEP) has to be set to prevent collapse of the alveoli, however at the same time overdistension should be avoided. Classic approaches of analyzing static respiratory system mechanics fail in particular if lung injury already prevails. A new approach of analyzing dynamic respiratory system mechanics to set PEEP uses the intratidal, volume-dependent compliance which is believed to stay relatively constant during one breath only if neither atelectasis nor overdistension occurs. To test the success of this dynamic approach systematically at bedside or in an animal study, automation of the computing steps is necessary. A decision support system for optimizing PEEP in form of a Graphical User Interface (GUI) was targeted. Respiratory system mechanics were analyzed using the gliding SLICE method. The resulting shapes of the intratidal compliance-volume curve were classified into one of six categories, each associated with a PEEP-suggestion. The GUI should include a graphical representation of the results as well as a quality check to judge the reliability of the suggestion. The implementation of a user-friendly GUI was successfully realized. The agreement between modelled and measured pressure data [expressed as root-mean-square (RMS)] tested during the implementation phase with real respiratory data from two patient studies was below 0.2 mbar for data taken in volume controlled mode and below 0.4 mbar for data taken in pressure controlled mode except for two cases with RMS < 0.6 mbar. Visual inspections showed, that good and medium quality data could be reliably identified. The new GUI allows visualization of intratidal compliance-volume curves on a breath-by-breath basis. The automatic categorisation of curve shape into one of six shape

  11. Fluctuation in measurements of pulmonary nodule under tidal volume ventilation on four-dimensional computed tomography: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Tateishi, Ukihide [National Cancer Center Hospital, Division of Diagnostic Radiology, Chuo-ku, Tokyo (Japan); Tsukagoshi, Shinsuke; Inokawa, Hiroyasu; Okumura, Miwa [Toshiba Medical Systems Corporation, CT Systems Development, Otawara (Japan); Moriyama, Noriyuki [National Cancer Center, Division of Cancer Screening, Research Center for Cancer Prevention and Screening, Tokyo (Japan)

    2008-10-15

    The present study aimed to assess the feasibility of four-dimensional (4D) chest computed tomography (CT) under tidal volume ventilation and the impact of respiratory motion on quantitative analysis of CT measurements. Forty-four pulmonary nodules in patients with metastatic disease were evaluated. CT examinations were performed using a 256 multidetector-row CT (MDCT) unit. Volume data were obtained from the lower lung fields (128 mm) above the diaphragm during dynamic CT acquisition. The CT parameters used were 120 kV, 100 or 150 mA, 0.5 s{sup -1}, and 0.5 mm collimation. Image data were reconstructed every 0.1 s during one respiratory cycle by a 180 reconstruction algorithm for four independent fractions of the respiratory cycle. Pulmonary nodules were measured along their longest and shortest axes using electronic calipers. Automated volumetry was assessed using commercially available software. The diameters of long and short axes in each frame were 9.0-9.6 mm and 7.1-7.5 mm, respectively. There was fluctuation of the long axis diameters in the third fraction. The mean volume in each fraction ranged from 365 to 394 mm{sup 3}. Statistically significant fluctuation was also found in the third fraction. 4D-CT under tidal volume ventilation is feasible to determine diameter or volume of the pulmonary nodule. (orig.)

  12. Mechanical ventilation in pediatric intensive care units during the season for acute lower respiratory infection: a multicenter study.

    Science.gov (United States)

    Farias, Julio A; Fernández, Analía; Monteverde, Ezequiel; Flores, Juan C; Baltodano, Arístides; Menchaca, Amanda; Poterala, Rossana; Pánico, Flavia; Johnson, María; von Dessauer, Bettina; Donoso, Alejandro; Zavala, Inés; Zavala, Cesar; Troster, Eduardo; Peña, Yolanda; Flamenco, Carlos; Almeida, Helena; Nilda, Vidal; Esteban, Andrés

    2012-03-01

    To describe the characteristics and outcomes of mechanical ventilation in pediatric intensive care units during the season of acute lower respiratory infections. Prospective cohort of infants and children receiving mechanical ventilation for at least 12 hrs. Sixty medical-surgical pediatric intensive care units. All consecutive patients admitted to participating pediatric intensive care units during a 28-day period. Of 2,156 patients admitted to pediatric intensive care units, 1185 (55%) received mechanical ventilation for a median of 5 days (interquartile range 2-8). Median age was 7 months (interquartile range 2-25). Main indications for mechanical ventilation were acute respiratory failure in 78% of the patients, altered mental status in 15%, and acute on chronic pulmonary disease in 6%. Median length of stay in the pediatric intensive care units was 10 days (interquartile range 6-18). Overall mortality rate in pediatric intensive care units was 13% (95% confidence interval: 11-15) for the entire population, and 39% (95% confidence interval: 23 - 58) in patients with acute respiratory distress syndrome. Of 1150 attempts at liberation from mechanical ventilation, 62% (95% confidence interval: 60-65) used the spontaneous breathing trial, and 37% (95% confidence interval: 35-40) used gradual reduction of ventilatory support. Noninvasive mechanical ventilation was used initially in 173 patients (15%, 95% confidence interval: 13-17). In the season of acute lower respiratory infections, one of every two children admitted to pediatric intensive care units requires mechanical ventilation. Acute respiratory failure was the most common reason for mechanical ventilation. The spontaneous breathing trial was the most commonly used method for liberation from mechanical ventilation.

  13. Comparison of INSURE method with conventional mechanical ventilation after surfactant administration in preterm infants with respiratory distress syndrome: therapeutic challenge.

    Directory of Open Access Journals (Sweden)

    Fatemeh Sadat Nayeri

    2014-08-01

    Full Text Available Administration of endotracheal surfactant is potentially the main treatment for neonates suffering from RDS (Respiratory Distress Syndrome, which is followed by mechanical ventilation. Late and severe complications may develop as a consequence of using mechanical ventilation. In this study, conventional methods for treatment of RDS are compared with surfactant administration, use of mechanical ventilation for a brief period and NCPAP (Nasal Continuous Positive Airway Pressure, (INSURE method ((Intubation, Surfactant administration and extubation. A randomized clinical trial study was performed, including all newborn infants with diagnosed RDS and a gestational age of 35 weeks or less, who were admitted in NICU of Valiasr hospital. The patients were then divided randomly into two CMV (Conventional Mechanical Ventilation and INSURE groups. Surfactant administration and consequent long-term mechanical ventilation were done in the first group (CMV group. In the second group (INSURE group, surfactant was administered followed by a short-term period of mechanical ventilation. The infants were then extubated, and NCPAP was embedded. The comparison included crucial duration of mechanical ventilation and oxygen therapy, IVH (Intraventricular Hemorrhage, PDA (Patent Ductus Arteriosus, air-leak syndromes, BPD (Broncho-Pulmonary Dysplasia and mortality rate. The need for mechanical ventilation in 5th day of admission was 43% decreased (P=0.005 in INSURE group in comparison to CMV group. A decline (P=0.01 in the incidence of IVH and PDA was also achieved. Pneumothorax, chronic pulmonary disease and mortality rates, were not significantly different among two groups. (P=0.25, P=0.14, P=0.25, respectively. This study indicated that INSURE method in the treatment of RDS decreases the need for mechanical ventilation and oxygen-therapy in preterm neonates. Moreover, relevant complications as IVH and PDA were observed to be reduced. Thus, it seems rationale to

  14. Can Tracheostomy Improve Outcome and Lower Resource Utilization for Patients with Prolonged Mechanical Ventilation?

    Institute of Scientific and Technical Information of China (English)

    Ciou-Rong Yuan; Tzuo-Yun Lan; Gau-Jun Tang

    2015-01-01

    Background:It is not clear whether the benefits oftracheostomy remain the same in the population.This study aimed to better examine the effect of tracheostomy on clinical outcome among prolonged ventilator patients.Methods:Data were from the medical claims data in Taiwan.A total of 3880 patients with ventilator use for more than 14 days between 2005 and 2009 were identified.Among them,645 patients with tracheostomy conducted within 30 days of ventilator use were compared to 2715 patients without tracheostomy on death during hospitalization and study period,and successful weaning and medical utilization during hospitalization.Cox proportional hazards and linear regression models were used to examine the associations between tracheostomy and the main outcomes.Results:The tracheostomy rate was 30%,and 55% of tracheostomies were performed within 30 days of mechanical ventilation.After adjustments,patients with tracheostomy were at a lower risk of death during hospitalization (hazard ratio [HR] =0.51;95% confidence interval [CI] =0.43-0.61) and 5-year observation (HR =0.73;95% CI =0.66-0.81),and a lower probability of successful weaning (HR =0.88;95% CI =0.79-0.99).Higher medical use was also observed in patients with tracheostomy.Conclusions:The beneficial effect for tracheostomy observed in our data was the reduction of death.However,patients with tracheostomy were less likely to wean and more likely to consume medical resources.

  15. AUTOPILOT-BT: a system for knowledge and model based mechanical ventilation.

    Science.gov (United States)

    Lozano, S; Möller, K; Brendle, A; Gottlieb, D; Schumann, S; Stahl, C A; Guttmann, J

    2008-01-01

    A closed-loop system (AUTOPILOT-BT) for the control of mechanical ventilation was designed to: 1) autonomously achieve goals specified by the clinician, 2) optimize the ventilator settings with respect to the underlying disease and 3) automatically adapt to the individual properties and specific disease status of the patient. The current realization focuses on arterial oxygen saturation (SpO(2)), end-tidal CO(2) pressure (P(et)CO(2)), and positive end-expiratory pressure (PEEP) maximizing respiratory system compliance (C(rs)). The "AUTOPILOT-BT" incorporates two different knowledge sources: a fuzzy logic control reflecting expert knowledge and a mathematical model based system that provides individualized patient specific information. A first evaluation test with respect to desired end-tidal-CO(2)-level was accomplished using an experimental setup to simulate three different metabolic CO(2) production rates by means of a physical lung simulator. The outcome of ventilator settings made by the "AUTOPILOT-BT" system was compared to those produced by clinicians. The model based control system proved to be superior to the clinicians as well as to a pure fuzzy logic based control with respect to precision and required settling time into the optimal ventilation state.

  16. Performance of a demand controlled mechanical extract ventilation system for dwellings

    Directory of Open Access Journals (Sweden)

    I. Pollet

    2013-10-01

    Full Text Available The main aim of ventilation is to guarantee a good indoor air quality, related to the energy consumed for heating and fan(s. Active or passive heat recovery systems seem to focus on the reduction of heating consumption at the expense of fan electricity consumption and maintenance. In this study, demandcontrolled mechanical extract ventilation systems of Renson (DCV1 and DCV2, based on natural supply in the habitable rooms and mechanical extraction in the wet rooms (or even the bedrooms, was analysed for one year by means of multi-zone Contam simulations on a reference detached house and compared with standard MEV and mechanical extract ventilation systems with heat recovery (MVHR. To this end, IAQ, total energy consumption, CO2 emissions and total cost of the systems are determined. The results show that DCV systems with increased supply air flow rates or direct mechanical extract from bedrooms can significantly improve IAQ, while reducing total energy consumption compared to MEV. Applying DCV reduces primary heating energy consumption and yearly fan electricity consumption at most by 65% to 50% compared to MEV. Total operational energy costs and CO2 emissions of DCV are similar when compared to MVHR. Total costs of DCV systems over 15 years are smaller when compared to MVHR due to lower investment and maintenance costs.

  17. Mechanical ventilation in acute respiratory distress syndrome: The open lung revisited.

    Science.gov (United States)

    Amado-Rodríguez, L; Del Busto, C; García-Prieto, E; Albaiceta, G M

    2017-02-23

    Acute respiratory distress syndrome (ARDS) is still related to high mortality and morbidity rates. Most patients with ARDS will require ventilatory support. This treatment has a direct impact upon patient outcome and is associated to major side effects. In this regard, ventilator-associated lung injury (VALI) is the main concern when this technique is used. The ultimate mechanisms of VALI and its management are under constant evolution. The present review describes the classical mechanisms of VALI and how they have evolved with recent findings from physiopathological and clinical studies, with the aim of analyzing the clinical implications derived from them. Lastly, a series of knowledge-based recommendations are proposed that can be helpful for the ventilator assisted management of ARDS at the patient bedside. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  18. Assessment of positive end-expiratory pressure induced lung volume change by ultrasound in mechanically ventilated patients%床旁超声对机械通气患者呼气末正压诱导肺容积改变的评估价值

    Institute of Scientific and Technical Information of China (English)

    沈鹏; 罗汝斌; 高玉芝; 王吉文; 张茂

    2014-01-01

    Objective To investigate the value of lung ultrasound for assessing positive endexpiratory pressure (PEEP)-induced lung volume change in mechanically ventilated patients with acute lung injury(ALI) or acute respiratory distress syndrome (ARDS).Methods Eighteen patients with ALI or ARDS were prospectively studied.P-V curves and lung ultrasound were performed at PEEP 12,8,4 and 0 cmH2O(1 cmH2O =0.098 kPa).PEEP-induced lung volume change was measured using the P-V curve method and lung ultrasound.Results Four lung ultrasound entities were defined:consolidation,multiple irregularly spaced B lines,multiple abutting B lines and normal aeration.For each of the 12 lung regions examined,PEEP-induced ultrasound changes were measured and an lung ultrasound score (LUS)was calculated.A highly significant correlation was found between PEEP-induced lung volume change measured by P-V curves and LUS change (r =0.82,P < 0.01).A statistically significant correlation was found between LUS change and PEEP-induced increase in PaO2 (r =0.66,P < 0.01).Conclusion PEEP-induced lung volume change can be adequately estimated with bedside lung ultrasound.Since lung ultrasound cannot assess PEEP-induced lung hyperinflation,it should not be the sole method for PEEP titration.%目的 探讨床旁超声在机械通气患者呼气末正压(PEEP)诱导肺容积改变的评估价值.方法 选取2011年6月至2012年12月浙江大学医学院附属第二医院急诊监护室(EICU)内符合急性肺损伤(ALI)或ARDS并接受机械通气的患者,采用Taema XTEND系列呼吸机专利的压力容积曲线测定程序自动测定PEEP为12、8、4、0 cmH2O(1 cmH2O =0.098 kPa)时的压力容积曲线,得到不同PEEP水平下的呼气末肺容积(EELV)并计算呼气末肺容积变化(△EELV),根据△EELV变化确定合适PEEP,在呼吸机测定压力容积曲线的同时使用床旁超声评估肺容积变化,计算肺部超声评分(LUS)及肺部超声评分变化(△LUS),相关计量数据进

  19. Indoor air quality and occupant satisfaction in five mechanically and four naturally ventilated open-plan office buildings

    DEFF Research Database (Denmark)

    Hummelgarrd, John; Juhl, Peter; Sæbjörnsson, Kristian

    2005-01-01

    The indoor air quality and occupant satisfaction was studied in five mechanically ventilated and four naturally ventilated open-plan office buildings in Copenhagen, using a simplified assessment procedure. Temperature and the concentration of CO2 were monitored in 2-10 locations per office...... to evaluate the variation throughout the offices. A representative measurement point was subsequently selected and measurements of the same parameters were made during one week. All offices were monitored during the same week and occupant responses to the indoor environment were collected via the Internet...... on the same day within that week. The study indicated that occupants in naturally ventilated offices have a lower prevalence of symptoms than those in mechanically ventilated offices. Although the room air temperature varied more and the concentration of CO2 was higher in the naturally ventilated offices...

  20. Physical restraint in mechanically ventilated ICU patients: a survey of French practice.

    Science.gov (United States)

    De Jonghe, Bernard; Constantin, Jean-Michel; Chanques, Gerald; Capdevila, Xavier; Lefrant, Jean-Yves; Outin, Hervé; Mantz, Jean

    2013-01-01

    To characterize the perceived utilization of physical restraint (PR) in mechanically ventilated intensive care unit (ICU) patients and to identify clinical and structural factors influencing PR use. A questionnaire was personally handed to one intensivist in 130 ICUs in France then collected on-site 2 weeks later. The questionnaire was returned by 121 ICUs (response rate, 93 %), 66 % of which were medical-surgical ICUs. Median patient-to-nurse ratio was 2.8 (2.5-3.0). In 82 % of ICUs, PR is used at least once during mechanical ventilation in more than 50 % of patients. In 65 % of ICUs, PR, when used, is applied for more than 50 % of mechanical ventilation duration. Physical restraint is often used during awakening from sedation and when agitation occurs and is less commonly used in patients receiving deep sedation or neuromuscular blockers or having severe tetraparesis. In 29 % of ICUs, PR is used in more than 50 % of awake, calm and co-operative patients. PR is started without written medical order in more than 50 % of patients in 68 % of ICUs, and removed without written medical order in more than 50 % of patients in 77 % of ICUs. Only 21 % of ICUs have a written local procedure for PR use. This survey in a country with a relatively high patient-to-nurse ratio shows that PR is frequently used in patients receiving mechanical ventilation, with wide variations according to patient condition. The common absence of medical orders for starting or removing PR indicates that these decisions are mostly made by the nurses.

  1. Rehabilitation Considerations for Children Dependent on Long-Term Mechanical Ventilation

    OpenAIRE

    Dumas, Helene M.

    2012-01-01

    The purposes of this paper are as follows (1) to describe the prevalence, etiology, and care settings for children dependent on long-term mechanical ventilation (MV); (2) to provide a brief introduction to MV and weaning; (3) to explore health care utilization and cost of care; and, primarily, (4) to discuss the rehabilitation needs of children dependent on long-term MV including activities of daily living, mobility, communication, psychosocial needs, and recreation and leisure. Children with...

  2. Outcome of Hematopoietic Stem Cell Recipients Who Were Mechanically Ventilated and Admitted to Intensive Care Units

    Directory of Open Access Journals (Sweden)

    Tsung-Ming Yang

    2007-01-01

    Conclusion: The ICU mortality rate of mechanically ventilated HSCT recipients was high. Factors associated with ICU mortality were older age, high APACHE II score, presence of shock, and higher respiratory or heart rate at the time of ICU admission. SLB might provide specific diagnosis in HSCT recipients with unexplained pulmonary infiltrates and aid modification of treatment. [J Formos Med Assoc 2007;106(4:295-301

  3. Increase the level of environmental safety for mechanical ventilation of light-oil storage tanks

    OpenAIRE

    Гарбуз, Сергей Викторович

    2015-01-01

    This paper evaluated the environmental risk of degassing light oil-storage tank, by quantifying emissions of hydrocarbon vapors in the air. To determine the basic parameters of the degassing tank that is carried out by mechanical ventilation, it has been created test bench geometrically similar to RVS-5000. Based on theoretical and experimental data, it is calculated the concentration of harmful substances (hydrocarbons) in the air for degassing method using in Ukraine, at all stages.Based on...

  4. Effects of hand massage and acupressure therapy for mechanically ventilated patients

    Directory of Open Access Journals (Sweden)

    Şebnem Çınar Yücel

    2015-10-01

    Results: According to the research findings, it wasn’t found significant as clinical which is the statistically significant difference in the physiological indicators of anxiety, perceived anxiety and dyspnoea except from oxygen saturation. Conclusion: In conclusion, our results suggest that hand massage and acupressure therapy might effectively relieve perceived dyspnoea and anxiety and reduce physiological indicators of anxiety in patients having mechanical ventilation support. The study provides a research-based intervention model for clinicians caring for MVP.

  5. Air compressor battery duration with mechanical ventilation in a field anesthesia machine.

    Science.gov (United States)

    Szpisjak, Dale F; Giberman, Anthony A

    2015-05-01

    Compressed air to power field anesthesia machine ventilators may be supplied by air compressor with battery backup. This study determined the battery duration when the compPAC ventilator's air compressor was powered by NiCd battery to ventilate the Vent Aid Training Test Lung modeling high (HC = 0.100 L/cm H2O) and low (LC = 0.020 L/cm H2O) pulmonary compliance. Target tidal volumes (VT) were 500, 750, and 1,000 mL. Respiratory rate = 10 bpm, inspiratory-to-expiratory time ratio = 1:2, and fresh gas flow = 1 L/min air. N = 5 in each group. Control limits were determined from the first 150 minutes of battery power for each run and lower control limit = mean VT - 3SD. Battery depletion occurred when VT was below the lower control limit. Battery duration ranged from 185.8 (±3.2) minutes in the LC-1000 group to 233.3 (±3.6) minutes in the HC-750 group. Battery duration of the LC-1000 group was less than all others (p = 0.027). The differences among the non-LC-1000 groups were not clinically significant. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  6. Continuous care and patients' basic needs during weaning from mechanical ventilation: A qualitative study.

    Science.gov (United States)

    Khalafi, Ali; Elahi, Nasrin; Ahmadi, Fazlollah

    2016-12-01

    Mechanical ventilation is associated with a number of risks and complications. Thus, rapid and safe weaning from mechanical ventilation is of great importance. Weaning is a complex and challenging process, requiring continuous care and knowledge of the patient. The aim of the present study was to describe the continuous care process during weaning as well as to analyse the facilitators and obstacles to the weaning process from start to finish from the perspective of intensive care unit (ICU) staff, particularly nurses. Twenty-two ICU staff members, including nurses and physicians, and three patients hospitalised in the ICU were enrolled in this qualitative study. Semi-structured interviews were used for data collection and the transcripts were analysed using qualitative content analysis. 'Continuous care' was found to be the patients' basic need during weaning from mechanical ventilation. Uninterrupted, stable, comprehensive and dynamic care and monitoring with immediate response to all physiological and psychological changes were features of continuous care. The three main themes identified by this study were time spent with the patient, comprehensive supervision and maintenance of the quality of care during shifts. Continuous and constant care should be provided during the weaning process. Such care will help to provide health care staff with a deeper understanding of the patient and his or her continuous changes, leading to a timely and favourable response during weaning. To achieve this goal, skill, communication and organisational changes are essential. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. [Intrathoracic drainage of a compressive pulmonary bulla in a patient receiving mechanical ventilation].

    Science.gov (United States)

    Sleth, J C; Aldebert, S; Safont, L; Knoerr, M F

    1998-01-01

    A lung suppuration may result in a lung bulla with its own course. We report such a case following a Pseudomonas aeruginosa pneumonia of the upper right lobe, after aspiration of gastric contents, in a 21-year-old tracheotomized patient in chronic post-traumatic coma. Mechanical ventilation (IPPV) was indicated because of respiratory insufficiency. The pneumonia was followed by an abscess and later a lung bulla, increasing in size under the effect of mechanical ventilation with progressive mediastinal compression. Surgery was contraindicated because of poor physical status. An acute episode of cardiac tamponade was controlled with an emergency transthoracic drain insertion into the bulla. The course was favourable after a drainage for 23 days and a persisting small cavity in the lung apex. All weaning attempts being unsuccessful, the patient was discharged under home mechanical ventilation. A CT-scan control 6 months later showed a normal lung parenchyma. The various alternative techniques to surgery for treatment of a lung bulla are discussed.

  8. Chest radiological patterns predict the duration of mechanical ventilation in children with RSV infection

    Energy Technology Data Exchange (ETDEWEB)

    Prodhan, Parthak [University of Arkansas for Medical Sciences, Division of Pediatric Critical Care and Cardiology, College of Medicine, Little Rock, AR (United States); Westra, Sjirk J. [Massachusetts General Hospital, Division of Pediatric Radiology, Boston, MA (United States); Lin, James [Mattel Children' s Hospital at UCLA, Division of Pediatric Critical Care, Los Angeles, CA (United States); Karni-Sharoor, Sarit [Shaarei Tzedek Medical Center, Pediatric Critical Care Unit, Jerusalem (Israel); Regan, Susan [Massachusetts General Hospital, Department of Medicine, Boston, MA (United States); Noviski, Natan [Massachusetts General Hospital, Pediatric Critical Care Medicine, Boston, MA (United States)

    2009-02-15

    RSV-infected children demonstrate various radiographic features, some of which are associated with worse clinical outcomes. To investigate whether specific chest radiological patterns in RSV-infected children with acute respiratory failure (ARF) in the peri-intubation period are associated with prolonged duration of mechanical ventilation. We included RSV-infected children <1 year of age admitted with ARF from 1996 through 2002 to the pediatric intensive care unit at Massachusetts General Hospital. Their chest radiographs were evaluated at three time-points: preintubation (day -1) and days 1 and 2 after intubation. Univariate and multiple logistic regressions models were utilized to investigate our objective. The study included 46 children. Using day 1 chest radiograph findings to predict duration of mechanical ventilation of >8 days, a backward stepwise regression arrived at a model that included age and right and left lung atelectasis. Using day 2 chest radiograph results, the best model included age and left lung atelectasis. A model combining the two days' findings yielded an area under the ROC curve of 0.92 with a satisfactory fit (P = 0.95). Chest radiological patterns around the time of intubation can identify children with RSV-associated ARF who would require prolonged mechanical ventilation. (orig.)

  9. Simultaneous tracheal and oesophageal pH monitoring during mechanical ventilation.

    Science.gov (United States)

    Hue, V; Leclerc, F; Gottrand, F; Martinot, A; Crunelle, V; Riou, Y; Deschildre, A; Fourier, C; Turck, D

    1996-01-01

    OBJECTIVE: To simultaneously record tracheal and oesophageal pH in mechanically ventilated children to determine: (1) the feasibility and safety of the method; (2) the incidence of gastro-oesophageal reflux (GOR) and pulmonary contamination; and (3) their associated risk factors. DESIGN: Prospective study. SETTING: Paediatric intensive care unit in a university hospital. PATIENTS: Twenty mechanically ventilated children (mean age 6.7 years) who met the following inclusion criteria: endotracheal tube with an internal diameter of 4 mm or more (cuffed or uncuffed), mechanical ventilation for an acute disease, no treatment with antiacids, prokinetics, or H2-receptor blockers, and no nasogastric or orogastric tube. METHODS: The tracheal antimony pH probe was positioned 1 cm below the distal end of the endotracheal tube. The oesophageal antimony pH probe was positioned at the lower third of the oesophagus. pH was recorded on a double channel recorder and analysed with EsopHogram 5.01 software and by examination of the trace. The following definitions were used: GOR index, percentage of time pH 4.8%; tracheal reflux, fall in tracheal pH Tracheal reflux (pH aspiration. Episodes of tracheal reflux were associated with a GOR index > 10% (p tracheal and oesophageal pH monitoring was feasible in the setting of this study. Tracheal reflux can occur without pathological GOR, and GOR may occur without tracheal reflux. Further prospective studies in larger groups of patients are now justified. PMID:8813870

  10. Analysis of thermal comfort and indoor air quality in a mechanically ventilated theatre

    Energy Technology Data Exchange (ETDEWEB)

    Kavgic, M.; Mumovic, D.; Young, A. [The Bartlett School of Graduate Studies, University College London, Gower Street, London, WC1E 6BT, England (United Kingdom); Stevanovic, Z. [Institute of Nuclear Sciences - Vinca, P.O. Box 522, 11001 Belgrade (RS)

    2008-07-01

    Theatres are the most complex of all auditorium structures environmentally. They usually have high heat loads, which are of a transient nature as audiences come and go, and from lighting which changes from scene to scene, and they generally have full or nearly full occupancy. Theatres also need to perform well acoustically, both for the spoken word and for music, and as sound amplification is less used than in other auditoria, background noise control is critically important. All these factors place constraints on the ventilation design, and if this is poor, it can lead to the deterioration of indoor air quality and thermal comfort. To analyse the level of indoor air quality and thermal comfort in a typical medium-sized mechanically ventilated theatre, and to identify where improvements could typically be made, a comprehensive post-occupancy evaluation study was carried out on a theatre in Belgrade. The evaluation, based on the results of monitoring (temperature, relative humidity, CO{sub 2}, air speed and heat flux) and modelling (CFD), as well as the assessment of comfort and health as perceived by occupants, has shown that for most of the monitored period the environmental parameters were within the standard limits of thermal comfort and IAQ. However, two important issues were identified, which should be borne in mind by theatre designers in the future. First, the calculated ventilation rates showed that the theatre was over-ventilated, which will have serious consequences for its energy consumption, and secondly, the displacement ventilation arrangement employed led to higher than expected complaints of cold discomfort, probably due to cold draughts around the occupants' feet. (author)

  11. 机械化盘区通风方法%Ventilation method of mechanized panel cutting

    Institute of Scientific and Technical Information of China (English)

    王海宁; 程哲

    2012-01-01

    依据某大型金属矿山井下机械化盘区通风的实际情况,在矿用空气幕替代辅扇的应用研究成功的基础上,现场开展硐室型风机机站的应用试验,对比研究的结果表明:硐室型风机机站可以有效替代传统风机机站,能在难以设置有风墙风机机站的巷道中安装运行,实现各盘区进风巷道风流的合理分配;硐室型风机机站能有效引射风流,控制风流短路,增加中段进风量达27.3m3/s,强化中段通风网络的排烟排尘效果,有利于保护工人的身体健康、提高矿井的有效风量率和促进矿井风流的有序流动;硐室型风机机站可以由单台风机或多台风机构成,安装在巷道侧壁的硐室内,增强多级机站通风方法的可靠性和适应性.%Based on the real underground mechanized panel cutting of some large metal mine, the application test of fan station in cavern with the successful substitute of air curtain for auxiliary fan was studied. The results show that the fan station in cavern is an effectively substitute for the traditional fan station in realizing the reasonable fan flow distribution in inlet air tunnel of every panel cutting, where the fan station with wind wall is hard to be installed. The fan station in cavern can effective induce the flow direction, control the flow short-circuit, and increase inlet air volume in middle tunnel to 27.3 m3/s. This increase could enhance the effect of smoke and dust exhaust in the section ventilation network, which is beneficial to protect the workers' health, improve the effective air volume rate and promote the orderly flow of mine airflow. The fan station in cavern can be constituted by single fan or multiple fans, and can be installed in the side wall of the tunnel. This enhances the reliability and flexibility of the multi-stage fan station.

  12. Effect of mechanical pressure-controlled ventilation in patients with disturbed respiratory function during laparoscopic cholecystectomy

    Directory of Open Access Journals (Sweden)

    Šurbatović Maja

    2013-01-01

    Full Text Available Background/Aim: Laparoscopic cholecystectomy is considered to be the gold standard for laparoscopic surgical procedures. In ASA III patients with concomitant respiratory diseases, however, creation of pneumoperitoneum and the position of patients during surgery exert additional negative effect on intraoperative respiratory function, thus making a higher challenge for the anesthesiologist than for the surgeon. The aim of this study was to compare the effect of intermittent positive pressure ventilation (IPPV and pressure controlled ventilation (PCV during general anesthesia on respiratory function in ASA III patients submitted to laparoscopic cholecystectomy. Methods. The study included 60 patients randomized into two groups depending on the mode of ventilation: IPPV or PCV. Respiratory volume (VT, peak inspiratory pressure (PIP, compliance (C, end-tidal CO2 pressure (PETCO2, oxygen saturation (SpO2, partial pressures of O2, CO2 (PaO2 and PaCO2 and pH of arterial blood were recorded within four time intervals. Results. There were no statistically significant differences in VT, SpO2, PaO2, PaCO2 and pH values neither within nor between the two groups. In time interval t1 there were no statistically significant differences in PIP, C, PETCO2 values between the IPPV and the PCV group. But, in the next three time intervals there was a difference in PIP, C, and PETCO2 values between the two groups which ranged from statistically significant to highly significant; PIP was lower, C and PETCO2 were higher in the PCV group. Conclusion. Pressure controlled ventilation better maintains stability regarding intraoperative ventilatory parameters in ASA III patients with concomitant respiratory diseases during laparoscopic cholecystectomy.

  13. Non-invasive mechanical ventilation after the successful weaning: a comparison with the venturi mask

    Directory of Open Access Journals (Sweden)

    Esra Adıyeke

    Full Text Available Abstract Background and objectives: This study compared the rates of acute respiratory failure, reintubation, length of intensive care stay and mortality in patients in whom the non-invasive mechanical ventilation (NIMV was applied instead of the routine venturi face mask (VM application after a successful weaning. Methods: Following the approval of the hospital ethics committee, 62 patients who were under mechanical ventilation for at least 48 hours were scheduled for this study. 12 patients were excluded because of the weaning failure during T-tube trial. The patients who had optimum weaning criteria after the T-tube trial of 30 minutes were extubated. The patients were kept on VM for 1 hour to observe the hemodynamic and respiratory stability. The group of 50 patients who were successful to wean randomly allocated to have either VM (n = 25, or NIV (n = 25. Systolic arterial pressure (SAP, heart rate (HR, respiratory rate (RR, PaO2, PCO2, and pH values were recorded. Results: The number of patients who developed respiratory failure in the NIV group was significantly less than VM group of patients (3 reintubation vs. 14 NIV + 5 reintubation in the VM group. The length of stay in the ICU was also significantly shorter in NIV group (5.2 ± 4.9 vs. 16.7 ± 7.7 days. Conclusions: The ratio of the respiratory failure and the length of stay in the ICU were lower when non-invasive mechanical ventilation was used after extubation even if the patient is regarded as ‘successfully weaned’. We recommend the use of NIMV in such patients to avoid unexpected ventilator failure.

  14. Time of elevation of head of bed for patients receiving mechanical ventilation and its related factors.

    Science.gov (United States)

    Martí-Hereu, L; Arreciado Marañón, A

    2017-06-08

    The semirecumbent position is a widespread recommendation for the prevention of pneumonia associated with mechanical ventilation. To identify the time of elevation of head of bed for patients under mechanical ventilation and the factors related to such elevation in an intensive care unit. An observational, descriptive cross-sectional study. Conducted in an intensive care unit of a tertiary hospital from April to June 2015. The studied population were mechanically ventilated patients. Daily hours in which patients remained with the head of the bed elevated (≥30°), socio-demographic data and clinical variables were recorded. 261 head elevation measurements were collected. The average daily hours that patients remained at ≥30° was 16h28' (SD ±5h38'), equivalent to 68.6% (SD ±23.5%) of the day. Factors related to elevations ≥30° for longer were: enteral nutrition, levels of deep sedation, cardiac and neurocritical diagnostics. Factors that hindered the position were: sedation levels for agitation and abdominal pathologies. Sex, age and ventilation mode did not show a significant relationship with bed head elevation. Although raising the head of the bed is an easy to perform, economical and measurable preventive measure, its compliance is low due to specific factors specific related o the patient's clinical condition. Using innovations such as continuous measurement of the head position helps to evaluate clinical practice and allows to carry out improvement actions whose impact is beneficial to the patient. Copyright © 2017 Sociedad Española de Enfermería Intensiva y Unidades Coronarias (SEEIUC). Publicado por Elsevier España, S.L.U. All rights reserved.

  15. Oral care in patients on mechanical ventilation in intensive care unit: literature review

    Directory of Open Access Journals (Sweden)

    Selma Atay

    2014-06-01

    Full Text Available intensive care patients needs to oral assessment and oral care for avoid complications caused by orafarengeal bacteria. In this literature review, it is aimed to determine the practice over oral hygiene in mechanical ventilator patients in intensive care unit. For the purpose of collecting data, Medline/pub MED and EBSCO HOST databases were searched with the keywords and lsquo;oral hygiene, oral hygiene practice, mouth care, mouth hygiene, intubated, mechanical ventilation, intensive care and critical care and rdquo; between the years of 2000- 2012. Inclusion criteria for the studies were being performed in adult intensive care unit patients on mechanical ventilation, published in peer-reviewed journals in English between the years of 2000-2012, included oral care practice and presence of a nurse among researchers. A total of 304 articles were identified. Six descriptive evaluation studies, three randomised controlled trials, four literature reviews, three meta-Analysis randomized clinical trials, one qualitative study and one semi-experimental study total 18 papers met all of the inclusion criteria. Oral care is emphasized as an infection control practice for the prevention of Ventilator-Associated Pneumonia (VAP. In conclusion, we mention that oral care is an important nursing practice to prevent VAP development in intensive care unit patients; however, there is no standard oral evaluation tool and no clarity on oral care practice frequency, appropriate solution and appropriate material. It can be recommended that the study projects on oral care in intensive care patients to have high proof level and be experimental, and longitudinal. [Int J Res Med Sci 2014; 2(3.000: 822-829

  16. Mortality in mechanically ventilated patients of Guillain Barré Syndrome

    Directory of Open Access Journals (Sweden)

    Archana B Netto

    2011-01-01

    Full Text Available Background: The mortality of patients with Guillain Barré syndrome (GBS has varied widely with rates between 1-18%. Death results from pneumonia, sepsis, adult respiratory distress syndrome (ARDS and less frequently due to autonomic dysfunction or pulmonary embolism. There are only few studies which have used a large sample and have in detail analyzed the circumstances relating to death and the prognostic factors for the same in a cohort, including only mechanically ventilated patients. Objective: The objective of our study was to analyze the circumstances and factors related to mortality in mechanically ventilated patients of GBS. Materials and Methods: Case records of patients of GBS, satisfying National Institute of Neurological and Communicative Disorders and Stroke (NINCDS criteria, and requiring mechanical ventilation from 1984 to 2007, were analyzed. Results: A total of 273 GBS patients were managed with ventilatory support (190 men and 83 women during the period. Besides symmetrical paralysis in all patients, bulbar palsy was present in 186 (68.1%, sensory involvement in 88 (32.2% and symptomatic autonomic dysfunction in 72 (26.4% patients. The mortality was 12.1%. The factors determining mortality were elderly age group (P=0.03, autonomic dysfunction (P=0.03, pulmonary complications (P=0.001, hypokalemia (P=0.001 and bleeding (P=0.001 from any site. Logistic regression analysis showed the risk of mortality was 4.69 times more when pneumonia was present, 2.44 times more when hypokalemia was present, and 3.14 times more when dysautonomia was present. The odds ratio for age was 0.97 indicating that a higher age was associated with a higher risk of mortality. Conclusions: Ventilator associated pulmonary complications, bleeding and hypokalemia especially in elderly patients require optimal surveillance and aggressive therapy at the earliest for reducing the mortality in this group of GBS patients.

  17. Mechanical ventilation alone, and in the presence of sepsis, impair protein metabolism in the diaphragm of neonatal pigs

    Science.gov (United States)

    Mechanical ventilation (MV) impairs diaphragmatic function and diminishes the ability to wean from ventilatory support in adult humans. In normal neonatal pigs, animals that are highly anabolic, endotoxin (LPS) infusion induces sepsis, reduces peripheral skeletal muscle protein synthesis rates, but ...

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

    Institute of Scientific and Technical Information of China (English)

    Ye-Qiu Li; Zheng-Lan Zhao; Qin-Fang Li

    2016-01-01

    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-αlevels 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 level and respiratory

  19. Inspiratory muscle training to facilitate weaning from mechanical ventilation: protocol for a systematic review

    Directory of Open Access Journals (Sweden)

    Vermeulen Niki

    2011-08-01

    Full Text Available Abstract Background In intensive care, weaning is the term used for the process of withdrawal of mechanical ventilation to enable spontaneous breathing to be re-established. Inspiratory muscle weakness and deconditioning are common in patients receiving mechanical ventilation, especially that of prolonged duration. Inspiratory muscle training could limit or reverse these unhelpful sequelae and facilitate more rapid and successful weaning. Methods This review will involve systematic searching of five electronic databases to allow the identification of randomised trials of inspiratory muscle training in intubated and ventilated patients. From these trials, we will extract available data for a list of pre-defined outcomes, including maximal inspiratory pressure, the duration of the weaning period, and hospital length of stay. We will also meta-analyse comparable results where possible, and report a summary of the available pool of evidence. Discussion The data generated by this review will be the most comprehensive answer available to the question of whether inspiratory muscle training is clinically useful in intensive care. As well as informing clinicians in the intensive care setting, it will also inform healthcare managers deciding whether health professionals with skills in respiratory therapy should be made available to provide this sort of intervention. Through the publication of this protocol, readers will ultimately be able to assess whether the review was conducted according to a pre-defined plan. Researchers will be aware that the review is underway, thereby avoid duplication, and be able to use it as a basis for planning similar reviews.

  20. Modest reduction in risk for ventilator-associated pneumonia in critically ill patients receiving mechanical ventilation following topical oral chlorhexidine.

    Science.gov (United States)

    Scannapieco, Frank A; Binkley, Catherine J

    2012-09-01

    The sample (N = 547) included patients older than 18 years (328 men and 219 women from a total population of 10,913) admitted to 3 intensive care units (ICUs) (medical, surgical/trauma, and neuroscience) at Virginia Commonwealth University Medical Center. The sample size required to detect an interaction (ie, the effect of chlorhexidine and toothbrushing in combination) was determined to be larger than that required to detect main effects (ie, chlorhexidine alone or toothbrushing alone) for a test at a given level of significance. The study was designed to detect an interactive effect resulting in a 0.755 difference in mean Clinical Pulmonary Infection Score (CPIS) at a power of 80% and a significance level of .05. An interim analysis was done and a Bonferroni adjustment was used to avoid inflation in the overall significance level related to interim analyses; for this reason, the level of significance for final analysis was .025. This was a randomized controlled clinical trial with a 2 × 2 factorial design. Patients were randomized to treatment within each ICU according to a permuted block design developed by the biostatistician before the start of the study. Staff who performed interventions (oral care) had no knowledge of patients' CPIS. Patients receiving mechanical ventilation were enrolled within 24 hours of intubation and were followed for up to 14 days. Dates of recruitment were not disclosed. Lung infection, resulting from aspiration of potential bacterial pathogens, such as Staphylococcus aureus, Streptococcus pneumoniae, or gram-negative rods that first colonize the oral cavity and oropharynx. Oral topical 0.12 % chlorhexidine gluconate, toothbrushing, or both (applied 4 times per day) were tested to determine their impact, if any, on incidence of lung infection in this cohort. The CPIS was assessed as the primary outcome variable. This score consists of the sum of points assigned to 6 clinical and laboratory variables (yielding a score from 0 to 12

  1. Respiratory mechanics and plasma levels of tumor necrosis factor alpha and interleukin 6 are affected by gas humidification during mechanical ventilation in dogs.

    Directory of Open Access Journals (Sweden)

    Claudia Hernández-Jiménez

    Full Text Available The use of dry gases during mechanical ventilation has been associated with the risk of serious airway complications. The goal of the present study was to quantify the plasma levels of TNF-alpha and IL-6 and to determine the radiological, hemodynamic, gasometric, and microscopic changes in lung mechanics in dogs subjected to short-term mechanical ventilation with and without humidification of the inhaled gas. The experiment was conducted for 24 hours in 10 dogs divided into two groups: Group I (n = 5, mechanical ventilation with dry oxygen dispensation, and Group II (n = 5, mechanical ventilation with oxygen dispensation using a moisture chamber. Variance analysis was used. No changes in physiological, hemodynamic, or gasometric, and radiographic constants were observed. Plasma TNF-alpha levels increased in group I, reaching a maximum 24 hours after mechanical ventilation was initiated (ANOVA p = 0.77. This increase was correlated to changes in mechanical ventilation. Plasma IL-6 levels decreased at 12 hours and increased again towards the end of the study (ANOVA p>0.05. Both groups exhibited a decrease in lung compliance and functional residual capacity values, but this was more pronounced in group I. Pplat increased in group I (ANOVA p = 0.02. Inhalation of dry gas caused histological lesions in the entire respiratory tract, including pulmonary parenchyma, to a greater extent than humidified gas. Humidification of inspired gases can attenuate damage associated with mechanical ventilation.

  2. Respiratory mechanics and plasma levels of tumor necrosis factor alpha and interleukin 6 are affected by gas humidification during mechanical ventilation in dogs.

    Science.gov (United States)

    Hernández-Jiménez, Claudia; García-Torrentera, Rogelio; Olmos-Zúñiga, J Raúl; Jasso-Victoria, Rogelio; Gaxiola-Gaxiola, Miguel O; Baltazares-Lipp, Matilde; Gutiérrez-González, Luis H

    2014-01-01

    The use of dry gases during mechanical ventilation has been associated with the risk of serious airway complications. The goal of the present study was to quantify the plasma levels of TNF-alpha and IL-6 and to determine the radiological, hemodynamic, gasometric, and microscopic changes in lung mechanics in dogs subjected to short-term mechanical ventilation with and without humidification of the inhaled gas. The experiment was conducted for 24 hours in 10 dogs divided into two groups: Group I (n = 5), mechanical ventilation with dry oxygen dispensation, and Group II (n = 5), mechanical ventilation with oxygen dispensation using a moisture chamber. Variance analysis was used. No changes in physiological, hemodynamic, or gasometric, and radiographic constants were observed. Plasma TNF-alpha levels increased in group I, reaching a maximum 24 hours after mechanical ventilation was initiated (ANOVA p = 0.77). This increase was correlated to changes in mechanical ventilation. Plasma IL-6 levels decreased at 12 hours and increased again towards the end of the study (ANOVA p>0.05). Both groups exhibited a decrease in lung compliance and functional residual capacity values, but this was more pronounced in group I. Pplat increased in group I (ANOVA p = 0.02). Inhalation of dry gas caused histological lesions in the entire respiratory tract, including pulmonary parenchyma, to a greater extent than humidified gas. Humidification of inspired gases can attenuate damage associated with mechanical ventilation.

  3. Individuality of breathing patterns in patients under noninvasive mechanical ventilation evidenced by chaotic global models

    Science.gov (United States)

    Letellier, Christophe; Rodrigues, Giovani G.; Muir, Jean-François; Aguirre, Luis A.

    2013-03-01

    Autonomous global models based on radial basis functions were obtained from data measured from patients under noninvasive mechanical ventilation. Some of these models, which are discussed in the paper, turn out to have chaotic or quasi-periodic solutions, thus providing a first piece of evidence that the underlying dynamics of the data used to estimate the global models are likely to be chaotic or, at least, have a chaotic component. It is explicitly shown that one of such global models produces attractors characterized by a Horseshoe map, two models produce toroidal chaos, and one model produces a quasi-periodic regime. These topologically inequivalent attractors evidence the individuality of breathing profiles observed in patient under noninvasive ventilation.

  4. Severe pediatric acute respiratory distress syndrome due to scrub typhus: Successful ventilation with airway pressure release ventilation mode after becoming refractory to protective ventilation

    Directory of Open Access Journals (Sweden)

    Sudha Chandelia

    2017-01-01

    Full Text Available Scrub typhus can affect lungs from mild illness like pneumonitis to a severe illness like acute respiratory distress syndrome (ARDS. Such patients may be very challenging to treat when their hypoxemia becomes severe and refractory to treatment. Main treatment is supportive in terms of mechanical ventilation. In adult ARDS, low tidal volume (TV ventilation has been recommended, but there is no consensus on most effective ventilation mode in children. We present a case of a 12-year-old girl who developed severe ARDS (PO 2 /FiO 2 ratio - 58, refractory to low TV ventilation. There was a rapid improvement in oxygenation on the application of airway pressure release ventilation (APRV mode within ΍ h. She was successfully ventilated and weaned off the ventilator over 5 days. This case highlights the utility of APRV mode of ventilation as a rescue therapy for severe refractory ARDS in children.

  5. Mechanical Ventilation

    Science.gov (United States)

    ... include chest-x-rays and blood drawn to measure oxygen and carbon dioxide (“blood gases”). Members of the health care team (including doctors, nurses, respiratory therapists) will use this information to assess ...

  6. Mortality and morbidity analysis in neonates supported by invasive mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Azer Kılıç Başkan

    2012-12-01

    Full Text Available Objectives: To evaluate mortality, morbidity, and invasivemechanical ventilation complications in mechanicallyventilated neonates in a tertiary care hospital, Istanbul,Turkey.Materials and methods: The neonates followed on invasivemechanical ventilation from January 2008 to December2009 were included in the study. A chart is formed foreach patient to record patient delivery room and clinicaldata prospectively.Results: The study population consisted of 236 neonates.Eighty-five percent were born at ≤37 completed weeks ofgestation (n=201. Fifty-two percent (n=123 were males.The mean gestational age was 31.9±5 weeks. The meanbirthweight was 1870.8±921.8 g. Antenatal steroid ratewas 13.3% (n=20 in 150 cases born at ≤34 weeks of gestation.Respiratory distress syndrome (n=100, 42,3%,perinatal depression and asphyxia (n=51, 21,6%, andsepsis (n=47, 19.9% were the commonest indications.Mechanical ventilation related complications (nosocomialinfection (n=57, pulmonary hemorrhage (n=30,pneumonia (n=10, pneumothorax (n=9, and atelectasis(n=4 developed in 33.5% of neonates (n=79. Bronchopulmonarydysplasia was 9.3%, intracranial hemorrhage(≥grade 3 8.47%, periventricular leukomalacia 5.93%,necrotizing enterocolitis (>stage 2 0.42%, and retinopathyof prematurity (>stage 2 2.96%. Mortality rate was30.17%. Neonates born at 1000 gram (p<0.05, p<0.05,respectively.Conclusions: Low birthweight and low gestational ageare important risk factors for neonatal mortality and morbidity.Low frequency of antenatal steroid use may be acontributing factor to increase neonatal mortality and morbidity.J Clin Exp Invest 2012; 3(4: 483-492Key words: Neonate, invasive mechanical ventilation,mortality, morbidity

  7. Optimization of Ventilation System in Large-scale Mechanized Metal Mine%大型机械化金属矿山通风系统优化

    Institute of Scientific and Technical Information of China (English)

    龚开福; 李夕兵; 李国元; 时增辉

    2015-01-01

    In order to improve the underground ventilation effect in the large-scale trackless mechanized mine, the air volume required by trackless equipment in running was analyzed. Compared with the minimum dusting air speed in working face,and the air volume as maximum personals working at the same time,the minimum underground air-supply volume was de-termined;Ventilation network graph for underground mine was constructed based on Vensim software,and the wind flow path, fan parameters and structures were dynamically adjusted to realize more air volume for more trackless equipment,so as to a-chieve the purpose of optimizing the mine ventilation system. The ventilation effect in a large-scale trackless mechanized mine in Guizhou showed that the trackless equipment needs most of air volume,which are considered as the minimum ventilation vol-ume of underground mine;In combination with Vensim ventilation network diagram,the positions of the fan and the structures were determined,and the air door opening and fan speed were dynamically adjusted to optimize the wind flow path and air vol-ume;The rigid duct can greatly reduce the ventilation resistance. The optimization from several aspects above can improve ven-tilation effect of the large mechanized underground metal mine.%为了改善大型无轨机械化矿山井下通风效果,分析了无轨设备运行时的需风量,并与工作面最小排尘风速、井下同时工作的最多人数需风量相比对,确定了井下最少供风量;基于Vensim通风软件构建了井下通风网络图,并对风流路径、风机参数、构筑物进行动态调节,使无轨设备相对集中的地方得到更多的风量,从而达到井下通风系统优化的目的。对贵州某大型无轨机械化矿山通风效果研究结果表明:无轨设备需风量最大,以此风量作为井下最少供风量;结合Vensim通风网络图,确定通风机与风构筑物的位置,并调节风门开度与风机转速,对

  8. High frequency mechanical ventilation affects respiratory system mechanics differently in C57BL/6J and BALB/c adult mice.

    Science.gov (United States)

    Hadden, Hélène

    2013-01-15

    We tested the hypothesis that high frequency ventilation affects respiratory system mechanical functions in C57BL/6J and BALB/c mice. We measured respiratory mechanics by the forced oscillation technique over 1h in anesthetized, intubated, ventilated BALB/c and C57BL/6J male mice. We did not detect any change in airway resistance, Rn, tissue damping, G, tissue elastance, H and hysteresivity, eta in BALB/c mice during 1h of ventilation at 150 or at 450 breaths/min; nor did we find a difference between BALB/c mice ventilated at 150 breaths/min compared with 450 breaths/min. Among C57BL/6J mice, except for H, all parameters remained unchanged over 1h of ventilation in mice ventilated at 150 breaths/min. However, after 10 and 30 min of ventilation at 450 breaths/min, Rn, and respiratory system compliance were lower, and eta was higher, than their starting value. We conclude that high frequency mechanical ventilation affects respiratory system mechanics differently in C57BL/6J and BALB/c adult mice.

  9. [Variation in inspiratory gas flow in pressure support ventilation. The effect on respiratory mechanics and respiratory work].

    Science.gov (United States)

    Sydow, M; Thies, K; Engel, J; Golisch, W; Buscher, H; Zinserling, J; Burchardi, H

    1996-11-01

    During pressure support ventilation (PSV), the timing of the breathing cycle is mainly controlled by the patient. Therefore, the delivered flow pattern during PSV might be better synchronised with the patient's demands than during volume-assisted ventilation. In several modern ventilators, inspiration is terminated when the inspiratory flow decreases to 25% of the initial peak value. However, this timing algorithm might cause premature inspiration termination if the initial peak flow is high. This could result not only in an increased risk of dyssynchronization between the patient and the ventilator, but also in reduced ventilatory support. On the other hand, a decreased peak flow might inappropriately increase the patient's inspiratory effort. The aim of our study was to evaluate the influence of the variation of the initial peak-flow rate during PSV on respiratory pattern and mechanical work of breathing. Six patients with chronic obstructive pulmonary disease (COPD) and six patients with no or minor nonobstructive lung pathology (control) were studied during PSV with different inspiratory flow rates by variations of the pressurisation time (Evita I, Drägerwerke, Lübeck, Germany). During the study period all patients were in stable circulatory conditions and in the weaning phase. Patients were studied in a 45 degrees semirecumbent position. Using the medium pressurization time (l s) during PSV the inspiratory pressure was individually adjusted to obtain a tidal volume of about 8 ml/kg body weight. Thereafter, measurements were performed during five pressurization times (ethics committee of our medical faculty. Gas flow was measured at the proximal end of the endotracheal tube with a pneumotachometer (Fleisch no. 2, Fleisch, Lausanne, Switzerland) and a differential pressure transducer. Tracheal pressure (Paw) was determined in the same position with a second differential pressure transducer (Dr. Fenyves & Gut, Basel, Switzerland). Esophageal pressure (Pes) was

  10. Infants with severe respiratory syncytial virus needed less ventilator time with nasal continuous airways pressure then invasive mechanical ventilation

    NARCIS (Netherlands)

    Borckink, Ilse; Essouri, Sandrine; Laurent, Marie; Albers, Marcel J. I. J.; Burgerhof, Johannes G. M.; Tissieres, Pierre; Kneyber, Martin C. J.

    AIM: Nasal continuous positive airway pressure (NCPAP) has been proposed as an early first-line support for infants with severe respiratory syncytial virus (RSV) infection. We hypothesised that infants <6 months with severe RSV would require shorter ventilator support on NCPAP than invasive

  11. Comparison of a Constant Air Volume (CAV) and a Demand Controlled Ventilation (DCV) System in a Residential Building

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig; Nielsen, Toke Rammer; Topp, Claus

    2008-01-01

    The aim of this paper was to compare the indoor climate and the energy performance of a Constant Air Volume (CAV) system of 0.5h-1 with a Demand Controlled Ventilation (DCV) system controlled by occupancy and relative humidity for a studio apartment. Furthermore the impact of building materials...... hygroscopic properties on indoor climate and energy consumption was investigated for the two systems. Dynamic simulations of the studio apartment were carried out in the program WUFI+ with weather data from Copenhagen including outside temperature end relative humidity. For the non-hygroscopic case...

  12. Liquid Ventilation

    Directory of Open Access Journals (Sweden)

    Qutaiba A. Tawfic

    2011-01-01

    Full Text Available Mammals have lungs to breathe air and they have no gills to breath liquids. When the surface tension at the air-liquid interface of the lung increases, as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen, as the inert carrier of oxygen and carbon dioxide offers a number of theoretical advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. The potential for multiple clinical applications for liquid-assisted ventilation will be clarified and optimized in future. Keywords: Liquid ventilation; perfluorochemicals; perfluorocarbon; respiratory distress; surfactant.

  13. The long-term mechanically ventilated patient. An outcomes management approach.

    Science.gov (United States)

    Burns, S M

    1998-03-01

    -management model, we recognize that other models may also result in comparable, favorable outcomes. It is important that those who adopt similar models of care delivery for managing patients requiring prolonged ventilation be scientific in their approach. Long-term studies of the efficacy of these models are essential if we are to truly provide quality care for our patients in the future. Unfortunately, as noted earlier, bias will be hard to overcome. Hospitals vested in rapidly establishing a stable financial bottom-line are likely to embrace quick applications. Projects with a true experimental design to evaluate efficacy, such as this one, will be rare in these organizations. Finally, it is critical that variables of interest be inclusive of specific quality indicators such as ventilator duration and complications rather than global institutional markers such as LOS. Standardization of variables of interest is imperative if outcomes are to be compared. For example, patients requiring long-term mechanical ventilation are identified by the AACN's Third National Study Group on weaning as those who require mechanical ventilation for more than 3 days. If we are to compare other variables of interest such as total ventilator duration, such as definition is essential or we will be comparing apples and oranges in the future. Provision of quality, cost-effective care for patients requiring prolonged ventilation is a true clinical challenge. Outcomes management is a multidisciplinary method of care delivery that is systematic and comprehensive in approach. Although little science exists related to the application of the model for patients requiring prolonged ventilation, preliminary reports are promising and warrant future applications and evaluation of the same.

  14. Chest physiotherapy in mechanically ventilated patients without pneumonia—a narrative review

    Science.gov (United States)

    De Regt, Jouke; Honoré, Patrick M.

    2017-01-01

    A beneficial adjuvant role of chest physiotherapy (CPT) to promote airway clearance, alveolar recruitment, and ventilation/perfusion matching in mechanically ventilated (MV) patients with pneumonia or relapsing lung atelectasis is commonly accepted. However, doubt prevails regarding the usefulness of applying routine CPT in MV subjects with no such lung diseases. In-depth narrative review based on a literature search for prospective randomized trials comparing CPT with a non-CPT strategy in adult patients ventilated for at least 48 h. Six relevant studies were identified. Sample size was small. Various CPT modalities were used including body positioning, manual chest manipulation (mobilization, percussion, vibration, and compression), and specific techniques such as lung hyperinflation and intrapulmonary percussion. Control subjects mostly received general nursing care and tracheal suction. In general, CPT was safe and supportive, yet had debatable or no significant impact on any relevant patient outcome parameter, including pneumonia. Current evidence does not support “prophylactic” CPT in adult MV patients without pneumonia. PMID:28203436

  15. Bed Microenvironment in Hospital Patient Rooms with Natural or Mechanical Ventilation

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Li, Yuguo; Georgiev, Emanuil

    2012-01-01

    We studied how to provide patients in bed with thermally comfortable microenvironment in both naturally and mechanically ventilated hospital rooms for both winter and summer seasons. A climate chamber was used to resemble a hospital room and thermal manikin to simulate a patient lying in a bed....... The °manikin was dressed and covered by a quilt with its head resting on a pillow. The effect of local heating was studied at room air temperature of 10 and 16 °C and of local cooling at 28 and 35 °C. Electrical radiant heater, heated blanket, heated pillow, personalized ventilation (PV) and heated boots were...... temperature of 22 °C. The effect of air movement (0.2, 0.4 and 1 m/s) at the bed vicinity was also studied. Electrical radiant heater in combination with heated bed showed to be the most effective at 10 and 16 °C and the combined use of PV and cooled mattress or ventilated bed was the most effective at 28...

  16. Effect of percutaneous endoscopic gastrostomy on gastro-esophageal reflux in mechanically-ventilated patients

    Institute of Scientific and Technical Information of China (English)

    Emmanuel E Douzinas; Andreas Tsapalos; Antonios Dimitrakopoulos; Evanthia Diamanti-Kandarakis; Alexandros D Rapidis; Charis Roussos

    2006-01-01

    AIM: To investigate the effect of percutaneous endoscopic gastrostomy (PEG) on gastroesophageal reflux (GER) in mechanically-ventilated patients.METHODS: In a prospective, randomized, controlled study 36 patients with recurrent or persistent ventilatorassociated pneumonia (VAP) and GER > 6% were divided into PEG group (n=16) or non-PEG group (n = 20).Another 11 ventilated patients without reflux (GER<3%) served as control group. Esophageal pH-metry was performed by the "pull through" method at baseline, 2and 7 d after PEG. Patients were strictly followed up for semi-recumbent position and control of gastric nutrient residue.RESULTS: A significant decrease of median (range) reflux was observed in PEG group from 7.8 (6.2-15.6) at baseline to 2.7 (0-10.4) on d 7 post-gastrostomy (P<0.01), while the reflux increased from 9 (6.2-22) to 10.8(6.3-36.6) (P<0.01) in non-PEG group. A significant correlation between GER (%) and the stay of nasogastric tube was detected (r=0.56, P<0.01).CONCLUSION: Gastrostomy when combined with semirecumbent position and absence of nutrient gastric residue reduces the gastroesophageal reflux in ventilated patients.

  17. Noninvasive Measurement of Carbon Dioxide during One-Lung Ventilation with Low Tidal Volume for Two Hours: End-Tidal versus Transcutaneous Techniques.

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    Full Text Available There may be significant difference between measurement of end-tidal carbon dioxide partial pressure (PetCO2 and arterial carbon dioxide partial pressure (PaCO2 during one-lung ventilation with low tidal volume for thoracic surgeries. Transcutaneous carbon dioxide partial pressure (PtcCO2 monitoring can be used continuously to evaluate PaCO2 in a noninvasive fashion. In this study, we compared the accuracy between PetCO2 and PtcCO2 in predicting PaCO2 during prolonged one-lung ventilation with low tidal volume for thoracic surgeries.Eighteen adult patients who underwent thoracic surgeries with one-lung ventilation longer than two hours were included in this study. Their PetCO2, PtcCO2, and PaCO2 values were collected at five time points before and during one-lung ventilation. Agreement among measures was evaluated by Bland-Altman analysis.Ninety sample sets were obtained. The bias and precision when PtcCO2 and PaCO2 were compared were 4.1 ± 6.5 mmHg during two-lung ventilation and 2.9 ± 6.1 mmHg during one-lung ventilation. Those when PetCO2 and PaCO2 were compared were -11.8 ± 6.4 mmHg during two-lung ventilation and -11.8 ± 4.9 mmHg during one-lung ventilation. The differences between PtcCO2 and PaCO2 were significantly lower than those between PetCO2 and PaCO2 at all five time-points (p < 0.05.PtcCO2 monitoring was more accurate for predicting PaCO2 levels during prolonged one-lung ventilation with low tidal volume for patients undergoing thoracic surgeries.

  18. Pressure-regulated volume controlled ventilation in acute respiratory failure of pulmonary diseases

    Directory of Open Access Journals (Sweden)

    M.E. Abou Shehata

    2012-07-01

    Conclusion: PRVC ventilation improves oxygenation parameters in ARF of different etiologies and is equally effective in management of ARF of different pulmonary disorders. The most important predictors for mortality were development of MODS and prolonged duration of MV as detected by logistic regression analysis.

  19. A knowledge- and model-based system for automated weaning from mechanical ventilation: technical description and first clinical application.

    Science.gov (United States)

    Schädler, Dirk; Mersmann, Stefan; Frerichs, Inéz; Elke, Gunnar; Semmel-Griebeler, Thomas; Noll, Oliver; Pulletz, Sven; Zick, Günther; David, Matthias; Heinrichs, Wolfgang; Scholz, Jens; Weiler, Norbert

    2014-10-01

    To describe the principles and the first clinical application of a novel prototype automated weaning system called Evita Weaning System (EWS). EWS allows an automated control of all ventilator settings in pressure controlled and pressure support mode with the aim of decreasing the respiratory load of mechanical ventilation. Respiratory load takes inspired fraction of oxygen, positive end-expiratory pressure, pressure amplitude and spontaneous breathing activity into account. Spontaneous breathing activity is assessed by the number of controlled breaths needed to maintain a predefined respiratory rate. EWS was implemented as a knowledge- and model-based system that autonomously and remotely controlled a mechanical ventilator (Evita 4, Dräger Medical, Lübeck, Germany). In a selected case study (n = 19 patients), ventilator settings chosen by the responsible physician were compared with the settings 10 min after the start of EWS and at the end of the study session. Neither unsafe ventilator settings nor failure of the system occurred. All patients were successfully transferred from controlled ventilation to assisted spontaneous breathing in a mean time of 37 ± 17 min (± SD). Early settings applied by the EWS did not significantly differ from the initial settings, except for the fraction of oxygen in inspired gas. During the later course, EWS significantly modified most of the ventilator settings and reduced the imposed respiratory load. A novel prototype automated weaning system was successfully developed. The first clinical application of EWS revealed that its operation was stable, safe ventilator settings were defined and the respiratory load of mechanical ventilation was decreased.

  20. The effect of different inflation volumes of laryngeal mask airway on efficacy of closed circuit controlled ventilation in pediatric cancer patients

    Institute of Scientific and Technical Information of China (English)

    Magda S. Azer; Ayman A. Ghoneim; Hossam Z. Ghobrial

    2013-01-01

    Objective:The laryngeal mask airway (LMA) is an established way for airway control during spontaneous ventila-tion. Its ability to deliver positive pressure ventilation without leakage especial y in low flow states is stil controversy. The aim of this study is to test the possibility of using LMA in pediatric closed circuit control ed ventilation, and to find out the optimum cuf volume to perform closed system ventilation. Methods:Twenty children scheduled for elective surgeries were enrol ed in a crossover study. Laryngeal mask airway was used. In stage I, the cuf was inflated with the maximum volume of air as rec-ommended by the manufacturers. Adjustment of volume of air inflated into the LMA cuf to the minimum volume to obtain the ef ective seal was done at stage II. The leak pressure, intracuf pressure and the leak volume were measured in both stages. Results:The cuf fil ing volume was significantly lower compared to the maximum cuf inflation volume in stage I. Leakage values showed significantly less values in stage II of the study with smal er cuf inflation volumes. The airway leakage pressure was significantly lower in stage II in comparison to stage I. Cuf inflation pressure in stage I showed marked elevation which dropped significantly after adjustment of cuf volume in stage II. Conclusion:Laryngeal mask airway is an ef ective tool to provide closed circuit control ed ventilation in pediatrics. Inflation of the cuf by the minimum volume of air needed to reach the just sealing pressure is suggested to minimize the leakage volume.

  1. 不同潮气量及呼气末正压机械通气对复苏后综合征患者的影响研究%Effect of Different Tidal Volumes and Mechanical Ventilation with Positive End-expiratory Pressure on Patients with Post-resuscitation Syndrome

    Institute of Scientific and Technical Information of China (English)

    熊华威; 黄亮; 曹春水; 杨继斌; 刘勇

    2013-01-01

    ,差异均有统计学意义(P<0.05).结论 低潮气量(6 ml/kg)+中等PEEP(6 cm H2O)可能是心肺复苏后24 h内较为合理的机械通气策略.%Objective To compare the effect of different tidal volumes ( TV ) and mechanical ventilation ( MV ) with positive end - expiratory pressure ( PEEP ) on patients with post - resuscitation syndrome ( PRS ), and discuss the ventilation strategy in cardiopulmonary resuscitation ( CPR ). Methods Thirty - six patients with PRS after cardiac arrest admitted in our hospital between December 2008 and December 2011 were randomly and evenly divided into group A, , group A2 , group A3, group B, , group B2 and group B3. Low TV ( 6 ml/kg ) plus low PEEP (3 cm H2O ) was applied to patients of group A,, low TV ( 6 ml/kg ) plus medium PEEP ( 6 cm H2O ) to group A2 , low TV ( 6 ml/kg ) plus high PEEP ( 12 cm H2O ) to group A3, routine TV ( 10 ml/kg ) plus low PEEP (3 cm H2O ) to group B, , routine TV ( 10 ml/kg ) plus medium PEEP ( 6 cm H2O ) to group B2 , and routine TV ( 10 ml/kg ) plus high PEEP ( 12 cm H2O ) to group B3. Timing was started after restoration of spontaneous circulation ( ROSC ). Patients'oxygenation index ( 01), blood gas analysis ( pH, PO2 , PCO2 ), central venous pressure ( CVP ), dopamine dose for basal MAP maintenance, heart rate ( HR ), hepatic and renal function ( ALT, TBiL, Cr), and Glasgow coma score ( GCS ) were measured and recorded at 1 h, 6 h, 12 h and 24 h. Results PO2 and 01 at 24 h was significantly lower than that of 1 h, 6 h and 12 h in all groups ( P <0. 05 ). PO2 and 01 at all time points in group A, was significantly lower than that of group A2 and A3, and that of group B, was lower than that of group B2 and B3 ( P < 0. 05 ). Dopamine dose for basal MAP maintenance, HR and CVP reached the highest at 6 h and decreased gradually during 12 ~ 24 h in all groups. Dopamine dose for basal MAP maintenance, HR and CVP at 6 h in all groups was significantly different from that of 1 h and 24 h ( P <0. 05

  2. Effect of Tracheostomy on Weaning Parameters in Difficult-to-Wean Mechanically Ventilated Patients: A Prospective Observational Study.

    Directory of Open Access Journals (Sweden)

    Chor-Kuan Lim

    Full Text Available Weaning parameters are commonly measured through an endotracheal tube in mechanically ventilated patients recovering from acute respiratory failure, however this practice has rarely been evaluated in tracheostomized patients. This study aimed to investigate changes in weaning parameters measured before and after tracheostomy, and to explore whether the data measured after tracheostomy were associated with weaning outcomes in difficult-to-wean patients.In a two-year study period, we enrolled orotracheally intubated patients who were prepared for tracheostomy due to difficult weaning. Weaning parameters were measured before and after the conversion to tracheostomy and compared, and the post-tracheostomy data were tested for associations with weaning outcomes.A total of 86 patients were included. After tracheostomy, maximum inspiratory pressure (mean difference (Δ = 4.4, 95% CI, 2.7 to 6.1, P<0.001, maximum expiratory pressure (Δ = 5.4, 95% CI, 2.9 to 8.0, P<0.001 and tidal volume (Δ = 33.7, 95% CI, 9.0 to 58.5, P<0.008 significantly increased, and rapid shallow breathing index (Δ = -14.6, 95% CI, -25.4 to -3.7, P<0.009 and airway resistance (Δ = -4.9, 95% CI, -5.8 to -4.0, P<0.001 significantly decreased. The patients who were successfully weaned within 90 days of the initiation of mechanical ventilation had greater increments in maximum inspiratory pressure (5.9 vs. 2.4, P = 0.04 and maximum expiratory pressure (8.0 vs. 2.0, P = 0.02 after tracheostomy than those who were unsuccessfully weaned.In conclusion, the conversion from endotracheal tube to tracheostomy significantly improved the measured values of weaning parameters in difficult-to-wean patients who subsequently weaned successfully from the mechanical ventilator. The change was significant only for airway resistance in patients who failed weaning.ClinicalTrials.gov NCT01312142.

  3. Effect of Tracheostomy on Weaning Parameters in Difficult-to-Wean Mechanically Ventilated Patients: A Prospective Observational Study

    Science.gov (United States)

    Lim, Chor-Kuan; Ruan, Sheng-Yuan; Lin, Feng-Ching; Wu, Chao-Ling; Chang, Hou-Tai; Jerng, Jih-Shuin; Wu, Huey-Dong; Yu, Chong-Jen

    2015-01-01

    Background and Objective Weaning parameters are commonly measured through an endotracheal tube in mechanically ventilated patients recovering from acute respiratory failure, however this practice has rarely been evaluated in tracheostomized patients. This study aimed to investigate changes in weaning parameters measured before and after tracheostomy, and to explore whether the data measured after tracheostomy were associated with weaning outcomes in difficult-to-wean patients. Methods In a two-year study period, we enrolled orotracheally intubated patients who were prepared for tracheostomy due to difficult weaning. Weaning parameters were measured before and after the conversion to tracheostomy and compared, and the post-tracheostomy data were tested for associations with weaning outcomes. Results A total of 86 patients were included. After tracheostomy, maximum inspiratory pressure (mean difference (Δ) = 4.4, 95% CI, 2.7 to 6.1, P<0.001), maximum expiratory pressure (Δ = 5.4, 95% CI, 2.9 to 8.0, P<0.001) and tidal volume (Δ = 33.7, 95% CI, 9.0 to 58.5, P<0.008) significantly increased, and rapid shallow breathing index (Δ = -14.6, 95% CI, -25.4 to -3.7, P<0.009) and airway resistance (Δ = -4.9, 95% CI, -5.8 to -4.0, P<0.001) significantly decreased. The patients who were successfully weaned within 90 days of the initiation of mechanical ventilation had greater increments in maximum inspiratory pressure (5.9 vs. 2.4, P = 0.04) and maximum expiratory pressure (8.0 vs. 2.0, P = 0.02) after tracheostomy than those who were unsuccessfully weaned. Conclusions In conclusion, the conversion from endotracheal tube to tracheostomy significantly improved the measured values of weaning parameters in difficult-to-wean patients who subsequently weaned successfully from the mechanical ventilator. The change was significant only for airway resistance in patients who failed weaning. Trial Registration ClinicalTrials.gov NCT01312142 PMID:26379127

  4. Assessment of Sedation and Analgesia in Mechanically Ventilated Patients in Intensive Care Unit

    Directory of Open Access Journals (Sweden)

    Udita Naithani

    2008-01-01

    Full Text Available Post traumatic stress resulting from an intensive care unit(ICU stay may be prevented by adequate level of sedation and analgesia. Aims of the study were reviewing the current practices of sedation and analgesia in our ICU setup and to assess level of sedation and analgesia to know the requirement of sedative and analgesics in mechani-cally ventilated ICU patients. This prospective observational study was conducted on 50 consecutive mechanically ventilated patients in ICU over a period of 6 months. Patient′s sedation level was assessed by Ramsay Sedation Scale (RSS = 1 : Agitated; 2,3 : Comfortable; 4,5,6 : Sedated and pain intensity by Behavioural Pain Scale (BPS = 3 :No pain, to 16 : Maximum pain. BPS, mean arterial pressure(MAP and heart rate(HR were assessed before and after painful stimulus (tracheal suction. Although no patient had received sedative and analgesics, mean Ramsay score was 3.52±1.92 with 30% patients categorized as ′agitated′, 12% as ′comfortable′ and 58% as ′sedated′ because of depressed consciousness level. Mean BPS at rest was 4.30±1.28 revealing background pain that further increased to 6.18±1.88 after painful stimulus. There was significant rise in HR (10.30%, MAP (7.56% and BPS (40.86% after painful stimulus, P< 0.0001. The correlation between BPS and Ramsay Score was negative and significant (P< 0.01. We conclude that there should be regular definition of the appropriate level of sedation and analgesia as well as monitoring of the desired level, using sedation and pain scales as a part of the total care for mechanically ventilated patients.

  5. Estimation of energy requirements for mechanically ventilated, critically ill patients using nutritional status

    Science.gov (United States)

    Kan, Mee-Nin; Chang, Han-Hsin; Sheu, Woei-Fen; Cheng, Chien-Hsiang; Lee, Bor-Jen; Huang, Yi-Chia

    2003-01-01

    Background There is very little information on what is considered an adequate energy intake for mechanically ventilated, critically ill patients. The purpose of the present study was to determine this energy requirement by making use of patients' nutritional status. Methods The study was conducted in a multidisciplinary intensive care unit of Taichung Veterans General Hospital, Taiwan. Patients were hemodynamically stable and not comatose, and were requiring at least 7 days of mechanical ventilation. Fifty-four patients successfully completed this study. The resting energy expenditure was measured using indirect calorimetry. The total energy requirement was considered 120% of the measured energy expenditure. The daily nutrient intake was recorded. Nutritional status was assessed using single and multiple parameters, nitrogen balance, and medical records, and was performed within 24 hours of admission and after 7 days in the intensive care unit. Results Fifteen patients were being underfed (requirement), 20 patients were in the appropriate feeding (AF) group (within ± 10% of total energy requirement), and 19 patients received overfeeding (>110% of total energy requirement). Patients in the underfeeding group received only 68.3% of their energy requirement, while the overfeeding group patients received up to 136.5% of their required calories. Only patients in the AF group had a positive nitrogen balance (0.04 ± 5.1) on day 7. AF group patients had a significantly higher Nutritional Risk Index value at day 7 than at day 1. Conclusion AF patients had more improvement in nutritional status than patients in the other feeding groups. To provide at least 120% of the resting energy expenditure seemed adequate to meet the caloric energy needs of hemodynamically stable, mechanically ventilated, critically ill patients. PMID:12974978

  6. Validity and reliability of “Persian Weaning Tool” in mechanically ventilated patients

    Science.gov (United States)

    Bazrafshan, Fatemeh; Irajpour, Alireza; Abbasi, Saeed; Mahaki, Behzad

    2016-01-01

    Background: “Persian Weaning Tool” (PWT) is the only specific, national protocol designed to assess patients’ readiness for weaning from mechanical ventilation in Iran. This study was developed to determine the validity and reliability of this protocol. Materials and Methods: This is a psychometric study conducted on 31 patients connected to mechanical ventilation were ready from weaning according to anesthesiologist's diagnosis and was selected through convenient sampling. The patients selected from Intensive Care Units (ICUs) of Al-Zahra Hospital in Isfahan. The sheet data collection includes demographic data, PWT; Burn's Wean Assessment Program (BWAP), and Morganroth's scale. To determine the inter-rater reliability between researcher and his partner, Pearson correlation and paired t-test were used. To assess the criterion validity of the PWT in relation to Burn's and Morganroth's weaning scales (as criteria), Pearson correlation and McNemar tests were used. To specify a minimum acceptable score of the PWT for weaning from mechanical ventilation, receiver operating characteristic curve was used. Results: The results showed that there was statistically significant correlation between score of PWT and BWAP (r = 0.370 with P < 0.05) and there were no statistically significant differences between these tools in terms of identification of patients’ readiness for weaning (P = 0.453). There was statistically significant correlation between PWT score obtained by researcher and his colleague (r = 0.928), and the reliability of this tool was approved. The PWTs cut of point was calculated as 57 (sensitivity = 0.679, specificity = 1). Conclusions: The reliability and validity of the PWT were confirmed for this study's sample size. Consequently, the findings of this study can be used to measure the PWTs effectiveness and applicability in ICUs.

  7. Placebo-controlled trial of midazolam sedation in mechanically ventilated newborn babies.

    Science.gov (United States)

    Jacqz-Aigrain, E; Daoud, P; Burtin, P; Desplanques, L; Beaufils, F

    1994-09-03

    Although midazolam is used for sedation of mechanically ventilated newborn babies, this treatment has not been evaluated in a randomised trial. We have done a prospective placebo-controlled study of the effects of midazolam on haemodynamic variables and sedation as judged by a five-item behaviour score. 46 newborn babies on mechanical ventilation for respiratory distress syndrome were randomly assigned to receive midazolam (n = 24) or placebo (n = 22) as a continuous infusion. Doses of midazolam were calculated to obtain plasma concentrations between 200 and 1000 ng/mL within 24 h of starting treatment and to maintain these values throughout the study. Haemodynamic and ventilatory variables were noted every hour, as were complications and possible side-effects of treatment. Mean (SD) duration of inclusion was 78.7 (30.9) h. 1 patient in the treatment group and 7 in the placebo group were withdrawn because of inadequate sedation (p < 0.05). Midazolam gave a significantly better sedative effect than placebo, as estimated by the behaviour score (p < 0.05). Heart rate and blood pressure were reduced by treatment but remained within the normal range for gestational age and there was no effect on ventilatory indices. The incidence of complications was similar in the two groups. No midazolam-related side-effects were noted. Continuous infusion of midazolam at doses adapted to gestational age induces effective sedation in newborn babies on mechanical ventilation, with positive effects on haemodynamic variables. The course of the respiratory distress syndrome was not influenced by this treatment. Midazolam was given over only a few days and the limited effects on heart rate and blood pressure that we report should not encourage long-term administration.

  8. Entropy correlates with Richmond Agitation Sedation Scale in mechanically ventilated critically ill patients.

    Science.gov (United States)

    Sharma, Ankur; Singh, Preet Mohinder; Trikha, Anjan; Rewari, Vimi; Chandralekha

    2014-04-01

    Sedation is routinely used in intensive care units. However due to absence of objective scoring systems like Bispectral Index and entropy our ability to regulate the degree of sedation is limited. This deficiency is further highlighted by the fact that agitation scores used in intensive care units (ICU) have no role in paralyzed patients. The present study compares entropy as a sedation scoring modality with Richmond Agitation Sedation Scale (RASS) in mechanically ventilated, critically ill patients in an ICU. Twenty-seven, mechanically ventilated, critically ill patients of either sex, 16-65 years of age, were studied over a period of 24 h. They received a standard sedation regimen consisting of a bolus dose of propofol 0.5 mg/kg and fentanyl 1 lg/kg followed by infusions of propofol and fentanyl ranging from 1.5 to 5 mg/kg/h and 0.5 to 2.0 lg/kg/h, respectively. Clinically relevant values of RASS for optimal ICU sedation (between 0 and -3) in non-paralyzed patients were compared to corresponding entropy values, to find if any significant correlation exists between the two. These entropy measurements were obtained using the Datex-Ohmeda-M-EntropyTM module. This module is presently not approved by Food and Drug Administration (FDA) for monitoring sedation in ICU. A total of 527 readings were obtained. There was a statistically significant correlation between the state entropy (SE) and RASS [Spearman's rho/rs = 0.334, p\\0.0001]; response entropy (RE) and RASS [Spearman's rho/rs = 0.341, p\\0.0001]). For adequate sedation as judged by a RASS value of 0 to -3, the mean SE was 57.86 ± 16.50 and RE was 67.75 ± 15.65. The present study illustrates that entropy correlates with RASS (between scores 0 and -3) when assessing the level of sedation in mechanically ventilated critically ill patients.

  9. Non-invasive mechanical ventilation in internal medicine departments: a pilot study

    Directory of Open Access Journals (Sweden)

    Micaela La Regina

    2013-09-01

    Full Text Available Non-invasive mechanical ventilation (NIMV has been shown to be an effective treatment in chronic and acute lung failure. Until a few years ago, all the different forms of mechanical ventilation were managed exclusively in intensive care units (ICU. However, the reduction in the number of ICU beds available and the high costs involved in running such units, together with the aging of the general population and the co-morbidities associated with this have meant that forms of mechanical ventilation are also used outside ICUs. In addition to emergency physicians and pneumologists, also internists have started to use NIMV on their wards in order to start treatment as early as possible and reduce costs. This is a preliminary study to explore the effectiveness, safety and feasibility of NIMV on a medical ward. The overall success rate was 68.8%; the likelihood of success was higher in patients who started NIMV earlier. The success rate was quite high (62% also among do-not-intubate patients, despite their poorer clinical condition. Few complications were reported and there was no increase in staff workload. No significant differences were found in in-hospital mortality between hypercapnic patients with chronic obstructive pulmonary disease (COPD exacerbation and hypercapnic patients with COPD plus pneumonia (27% vs 25% or between patients with pneumonia and patients with COPD plus pneumonia (26% vs 25%. These results are encouraging for the successful use of NIMV on medical wards. A careful selection of patients, educating and motivating staff in NIMV use, and close collaboration with resuscitators are all essential for this to be achieved.

  10. Complications in mechanically ventilated patients of Guillain–Barre syndrome and their prognostic value

    Science.gov (United States)

    Netto, Archana Becket; Taly, Arun B.; Kulkarni, Girish B.; Uma Maheshwara Rao, G. S.; Rao, Shivaji

    2017-01-01

    Introduction: The spectrum of various complications in critically ill Guillain–Barre syndrome (GBS) and its effect on the prognosis is lacking in literature. This study aimed at enumerating the complications in such a cohort and their significance in the prognosis and mortality. Materials and Methods: Retrospective case record analysis of all consecutive mechanically ventilated patients of GBS in neurology Intensive Care Unit (ICU) of a tertiary care institute for 10 years was done. Demographic, laboratory, and treatment details and outcome parameters were recorded. Results: Among the 173 patients were 118 men and 55 women (2.1:1), aged 1–84 years. The average number of ICU complications per patient was 6.8 ± 1.8 (median = 7, range = 1–12). The most common complication was tracheobronchitis (128). Other pulmonary complications were found in 36 patients. The next was metabolic hyponatremia (115) hypokalemia (67), hypocalcemia (13), stress hyperglycemia (10), hyperkalemia (8), hypernatremia (9). Sepsis (40), UTI (47), dysautonomia (27), hypoalbuminemia (76), anemia (75), seizures (8), paralytic ileus (5), bleeding (4), anoxic encephalopathy (3), organ failures (12), deep vein thrombosis (7), and drug rashes (1) were also noted. The complications, considered significant in causing death, Hughes scale ≤ 3 at discharge, prolonged mechanical ventilation (>21 days) and hospitalization (>36 days) were pneumonia, hyponatremia, hypokalemia, urinary infection, tracheobronchial infections, hypoalbuminemia, sepsis, anemia dysautonomia. Conclusion: Active monitoring and appropriate and early intervention by the clinician will improve the quality of life of these patients and reduce the cost of prolonged mechanical ventilation and ICU stay. PMID:28149085

  11. Effects of manual rib-cage compression versus PEEP-ZEEP maneuver on respiratory system compliance and oxygenation in patients receiving mechanical ventilation.

    Science.gov (United States)

    Santos, Flavio Renato Antunes Dos; Schneider Júnior, Luiz Carlos; Forgiarini Junior, Luiz Alberto; Veronezi, Jefferson

    2009-06-01

    Patients unable to perform breathing functions may be submitted to invasive mechanical ventilation. Chest physiotherapy acts directly on the treatment of these patients for the purpose of improving their lung function. The objective of this study was to evaluate the effects of manual rib-cage compression versus the positive end expiratory pressure-zero end expiratory pressure (PEEP-ZEEP) maneuver, on compliance of the respiratory system and oxygenation in patients under invasive mechanical ventilation. A double centric, prospective, randomized and crossover study, with patients under invasive mechanical ventilation, in controlled mode for more than 48 hours was carried out. The protocols of chest physiothe-rapy were randomly applied at an interval of 24 hours. Data of respiratory system compliance and oxygenation were collected before application of the protocols and 30 minutes after. Twelve patients completed the study. Intragroup analysis, for both techniques showed a statistically significant difference in tidal volume (p=0.002), static compliance (p=0.002) and dynamic compliance (p=0.002). In relation to oxygenation, in the group of manual rib-cage compression, peripheral oxygen saturation increased with a significant difference (p=0.011). Manual rib-cage compression and PEEP-ZEEP maneuver have positive clinical effects. In relation to oxygenation we found a favorable behavior of peripheral oxygen saturation in the group of manual rib-cage compression.

  12. Mechanical ventilation and the total artificial heart: optimal ventilator trigger to avoid post-operative autocycling - a case series and literature review

    Directory of Open Access Journals (Sweden)

    Arabia Francisco A

    2010-05-01

    Full Text Available Abstract Many patients with end-stage cardiomyopathy are now being implanted with Total Artificial Hearts (TAHs. We have observed individual cases of post-operative mechanical ventilator autocycling with a flow trigger, and subsequent loss of autocycling after switching to a pressure trigger. These observations prompted us to do a retrospective review of all TAH devices placed at our institution between August 2007 and May 2009. We found that in the immediate post-operative period following TAH placement, autocycling was present in 50% (5/10 of cases. There was immediate cessation of autocycling in all patients after being changed from a flow trigger of 2 L/minute to a pressure trigger of 2 cm H2O. The autocycling group was found to have significantly higher CVP values than the non-autocycling group (P = 0.012. Our data suggest that mechanical ventilator autocycling may be resolved or prevented by the use of a pressure trigger rather than a flow trigger setting in patients with TAHs who require mechanical ventilation.

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

    Directory of Open Access Journals (Sweden)

    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

  14. Variability of preference toward mechanical ventilator settings: a model-based behavioral analysis.

    Science.gov (United States)

    Allerød, Charlotte; Karbing, Dan S; Thorgaard, Per; Andreassen, Steen; Kjærgaard, Søren; Rees, Stephen E

    2011-12-01

    The purpose of this study was to evaluate Danish clinicians' opinions toward ventilator settings using standardized model-simulated patients. The models ensured that all clinicians received identical presentations of data and anticipated responses to changes in patient state, enabling opinions on the same patient cases to be obtained from different clinicians. Ten Danish intensive care clinicians' and a computerized decision support system each provided suggestions for respiratory frequency (f), tidal volume (Vt) and insoired oxygen fraction (FiO2) in the same 10 model-simulated patient cases. The 110 suggestions were then evaluated by the 10 clinicians in a ranking and classification procedure. Clinicians' preferences toward ventilator settings (Fio(2), Vt, and f) and the resulting simulated values of arterial oxygen saturation, peak inspiratory pressure, and pH were significantly different (P < .005). The results of the classification showed that clinicians generally had poor opinion of the advice provided by other clinicians and the decision support system, considering this advice to be unacceptable in 33% of cases and good only in 21%. The ranking procedure also showed that clinicians did not agree on the best and worst advice. The present study shows significant difference in opinion on appropriate settings of f, Vt, and Fio(2) in the same computerized decision support system model-simulated patient cases. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Respiratory mechanics in COPD patients who failed non-invasive ventilation: role of intrinsic PEEP.

    Science.gov (United States)

    Antonaglia, Vittorio; Ferluga, Massimo; Capitanio, Guido; Lucangelo, Umberto; Piller, Fulvia; Roman-Pognuz, Erik; Biancardi, Bruno; Caggegi, Giuseppe Davide; Zin, Walter A

    2012-10-15

    Non-invasive positive pressure ventilation (NPPV) is the first choice to treat exacerbations in COPD patients. NPPV can fail owing to different causes related to gas exchange impairment (RF group) or intolerance (INT group). To assess if the respiratory mechanical properties and the ratio between the dynamic and static intrinsic positive end-expiratory pressure (PEEP(i),dyn/PEEP(i),stat), reflecting lung mechanical inequalities, were different between groups, 29 COPD patients who failed NPPV (15 RF and 14 INT) were studied, early after the application of invasive ventilation. Blood gas analysis, clinical status, and mechanical properties were measured. pH was higher in INT patients before intubation (p<0.001). PEEP(i),dyn/PEEP(i),stat was found higher in INT group with (p=0.021) and without PEEP (ZEEP, p<0.01). PEEP(i),dyn/PEEP(i),stat was exponentially associated with the duration of NPPV in INT group (p=0.011). INT and RF patients had similar impairment of respiratory system resistance and elastance.

  16. Simulation on dissolute and dust dispersion in comprehensive mechanized heading face with forced-exhaust ventilation

    Institute of Scientific and Technical Information of China (English)

    NIE Wen; CHENG Wei-min; HAN Li; ZHOU Sheng-ju; YU Yan-bin; ZHAO Shan-shan

    2011-01-01

    According to the characteristics of comprehensive mechanized heading face,established the mathematical model of single-phase air flow with k-e two equations model,and have established k-e-(O)-kp mathematic model to solve two-phase flow of gas and particles in dust space with eulefian-eulerian method and eulerian-lagrangian method.Numerical solution of gas-particle two-phase flow was put forward based on collocated grid SIMPLE algorithm.Moreover,numerical simulation of dust concentration in fully mechanized caving face was carried out by using Fluent software.Finally,when in forced-exhaust ventilation circumstance,drawer type fan drum have less dust absorption,and most of dust spread to the other site; the dust concentration is inversely proportional to the distance from tunneling head,and the dust concentration has already diffused to decrease below 102 mg/m3 at the position ofx=12 m.Dust are more focused on relative side(in the range about y from 0 to 2 meter) of roadway space of press-ventilated fan drum,especially between tunneling place and drawer type fan drum; the roadway with road header have a higher dust concentration.These conclusions provide reliable theory basis for the dust prevention in comprehensive mechanized heading face.

  17. Is type 2 diabetes mellitus in mechanically ventilated adult trauma patients potentially related to the occurrence of ventilator-associated pneumonia?

    Directory of Open Access Journals (Sweden)

    Hadi Darvishi Khezri

    2016-01-01

    Full Text Available Background: Ventilator-associated pneumonia (VAP is a type of lung infection that typically affects critically ill patients undergoing mechanical ventilation (MV in the intensive care unit (ICU. Patients with type 2 diabetes mellitus (T2DM are considered to be more susceptible to several types of infections including community-acquired pneumonia. However, it is not clear whether T2DM is a risk factor for the development of VAP. The purpose of this study was to determine the risk of VAP for diabetic and nondiabetic mechanically ventilated trauma patients. Materials and Methods: This study is a secondary analysis of a prospective observational study of the history of T2DM in the ICU over a period of 1 year at Imam Khomeini Hospital in Iran. A total of 186 critically ill trauma patients who required at least 48 h of MV were monitored for the occurrence of VAP by their clinical pulmonary infection score (CPIS until ICU discharge, VAP diagnosis, or death. Results: Forty-one of the 186 patients developed VAP. The median time from hospitalization to VAP was 29.09 days (95% CI: 26.27-31.9. The overall incidence of VAP was 18.82 cases per 1,000 days of intubation (95% CI: 13.86-25.57. Risk of VAP in diabetic patients was greater than nondiabetic patients after adjustments for other potential factors [hazard ratio (HR: 10.12 [95% confidence interval (CI: 5.1-20.2; P < 0.0001]. Conclusion: The findings show that T2DM is associated with a significant increase in the occurrence of VAP in mechanically ventilated adult trauma patients.

  18. Invasive and Noninvasive Mechanical Ventilation For Acute Exacerbations Of Chronic Obstructive Pulmonary Disease

    Directory of Open Access Journals (Sweden)

    Abd-Hay I. Abd-Hay; Ahmed S. Alsaily* and Essam A. El-Moselhy

    2011-04-01

    Full Text Available Introduction: Acute exacerbation of chronic obstructive pulmonary disease (COPD is a frequent cause of hospitalization and intensive care unit admission. Respiratory failure from airflow obstruction is a direct consequence of acute airway narrowing. Aim of the study: It was to compare the efficacy of noninvasive mechanical ventilation (NIMV against conventional mechanical ventilation (CMV in patients with acute exacerbation of COPD. Patients and methods: Forty patients with acute exacerbation of COPD were recruited in the present study. A comparative, hospital based study design was used. All the cases were examined; clinically and laboratory. The patients were divided into two groups each include 20 patients. Group A received NIMV in the form of continuous positive airway pressure (CPAP and group B with CMV. Results: There were statistically significant decreases in respiratory rate, heart rate and diastolic blood pressure after 6 hours of CPAP in comparison to baseline parameters in group A. While, there were statistically significant increases in PaO2 and SaO2 after 6 hours of CPAP in comparison to baseline parameters. In group B there were statistically significant decreases in respiratory rate, heart rate, systolic blood pressure and diastolic blood pressure after 6 hours of CMV in comparison to baseline parameters. While, there were statistically significant increases in pH, PaO2, and SaO2 and a statistically significant decrease in PaCO2 after 6 hours of CMV in comparison to baseline parameters. Further, comparison of respiratory rate and hemodynamic parameters in both groups showed statistically significant decreases in respiratory rate, heart rate, systolic blood pressure and diastolic blood pressure in group A in comparison to group B. Finally, failure rate was 35.0% in group A (NIMV compared to 5.0% in group B (CMV with statistically significant difference. Conclusions and recommendations: Noninvasive mechanical ventilation is a safe

  19. Prognosis and weaning of elderly multiple organ dysfunction syndrome patients with invasive mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    Xiao Kun; Su Longxiang; Han Bingchao; Guo Chao; Feng Lin; Jiang Zhaoxu; Wang Huijuan

    2014-01-01

    Background Elderly multiple organ dysfunction syndrome (MODS) patients receiving invasive mechanical ventilation have poor prognosis in intensive care units (ICUs).We studied the usefulness of four commonly used severity scores and extrapulmonary factors that affected weaning to predict outcome of such patients.Methods Clinical data of 197 patients on admission to ICUs (from January 2009 to June 2012) were used retrospectively.The Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ,APACHE Ⅲ,Sample Acute Physiological Score (SAPS) Ⅱ and MODS scores were calculated.All the patients were grouped into survivors and nonsurvivors according to the prognosis.Patients,who weaned from ventilator (n=154),were subdivided into a successful weaning group and a failed weaning group.The receiver operating characteristic (ROC) curves and Logistic regression was used for prognostic and weaning assessment.Results Based on the outcomes,the areas under the ROC of APACHE Ⅱ,APACHE Ⅲ,SAPS Ⅱ,and MODS were 0.837,0.833,0.824,and 0.837,respectively.The Logistic regression analysis revealed that the odds ratio (OR) of underlying lung diseases,serum albumin and creatinine,and the number of organ failures was 2.374,0.920,1.003,and 1.547.APACHE Ⅱ scores on admission performed excellent (ROC:0.921) on the weaning assessments.Conclusions APACHE Ⅱ and MODS systems were marginally better for evaluating the prognosis of elderly MODS patients who received invasive mechanical ventilation.Underlying lung diseases,serum albumin,serum creatinine and the number of organ failures were independent prognostic factors.Using the APACHE Ⅱ scores on admission before weaning may increase the likelihood of successful weaning.(ClinicalTrial.gov identifier NCT01802983).

  20. Cost-Effectiveness Analysis of Heat and Moisture Exchangers in Mechanically Ventilated Critically Ill Patients

    Science.gov (United States)

    Menegueti, Mayra Goncalves; Auxiliadora-Martins, Maria; Nunes, Altacilio Aparecido

    2016-01-01

    Background Moisturizing, heating and filtering gases inspired via the mechanical ventilation (MV) circuits help to reduce the adverse effects of MV. However, there is still no consensus regarding whether these measures improve patient prognosis, shorten MV duration, decrease airway secretion and lower the incidence of ventilator associated pneumonia (VAP) and other complications. Objectives The aim of this study was to study the incremental cost-effectiveness ratio associated with the use of heat and moisture exchangers (HME) filter to prevent VAP compared with the heated humidifiers (HH) presently adopted by intensive care unit (ICU) services within the Brazilian Healthcare Unified System. Patients and Methods This study was a cost-effectiveness analysis (CEA) comparing HME and HH in preventing VAP (outcome) in mechanically ventilated adult patients admitted to an ICU of a public university hospital. Results The analysis considered a period of 12 months; MV duration of 11 and 12 days for patients in HH and HME groups, respectively and a daily cost of R$ 16.46 and R$ 13.42 for HH and HME, respectively. HME was more attractive; costs ranged from R$ 21,000.00 to R$ 22,000.00 and effectiveness was close to 0.71, compared with a cost of R$ 30,000.00 and effectiveness between 0.69 and 0.70 for HH. HME and HH differed significantly for incremental effectiveness. Even after an effectiveness gain of 1.5% in favor of HH, and despite the wide variation in the VAP rate, the HME effectiveness remained stable. The mean HME cost-effectiveness was lower than the mean HH cost-effectiveness, being the HME value close to R$ 44,000.00. Conclusions Our findings revealed that HH and HME differ very little regarding effectiveness, which makes interpretation of the results in the context of clinical practice difficult. Nonetheless, there is no doubt that HME is advantageous. This technology incurs lower direct cost. PMID:27843770

  1. Effect of a spacer on pulmonary aerosol deposition from a jet nebuliser during mechanical ventilation.

    Science.gov (United States)

    Harvey, C. J.; O'Doherty, M. J.; Page, C. J.; Thomas, S. H.; Nunan, T. O.; Treacher, D. F.

    1995-01-01

    BACKGROUND--Several factors have been identified which improve nebulised aerosol delivery in vitro. One of these is the addition of a spacer to the ventilator circuit which improves aerosol delivery from a jet nebuliser to a model lung by approximately 30%. The current study was designed to demonstrate whether similar improvements could be demonstrated in vivo. METHODS--Ten patients (seven men) were studied during mechanical ventilation (Siemens Servo 900C) after open heart surgery. Aerosol was delivered using a Siemens Servo 945 nebuliser system (high setting) driving a System 22 Acorn jet nebuliser (Medic-Aid) containing 3 ml technetium-99m labelled human serum albumin (99mTc-HSA (50 micrograms); activity in the first nebulisation, 90 MBq; in the second nebulisation, 185 MBq). Central and peripheral lung aerosol deposition and the time to complete deposition were measured using a gamma camera and compared when the nebuliser was connected to the inspiratory limb using a simple T-piece or a 600 ml spacer. RESULTS--The addition of the spacer increased total lung deposition (mean (SD) percentage initial nebuliser activity) from 2.2 (0.7)% to 3 (0.8)%. There was no difference in the time required to complete nebulisation (18.2 min v 18.3 min respectively for T-piece and spacer) or in the retention of activity in the nebuliser (46.2% v 47.1% respectively). CONCLUSIONS--The combination of a spacer with a jet nebuliser increased lung deposition by 36% in mechanically ventilated patients and is a simple way of increasing drug deposition or reducing the amount of an expensive drug required for nebulisation. Images PMID:7886649

  2. Ultrafine and Fine Particulate Matter Inside and Outside of Mechanically Ventilated Buildings.

    Science.gov (United States)

    Miller, Shelly L; Facciola, Nick A; Toohey, Darin; Zhai, John

    2017-01-28

    The objectives of this study were to measure levels of particulate matter (PM) in mechanically ventilated buildings and to improve understanding of filtration requirements to reduce exposure. With the use of an Ultra High Sensitivity Aerosol Spectrometer and an Aerodyne Mass Spectrometer, ultrafine (0.055-0.1 μm) and fine (0.1-0.7 μm) indoor and outdoor PM was measured as a function of time in an office, a university building, and two elementary schools. Indoor particle levels were highly correlated with outdoor levels. Indoor and outdoor number concentrations in Denver were higher than those in Boulder, with the highest number concentrations occurring during summer and fall. The ratio of indoor-to-outdoor (I/O) PM was weakly but positively correlated with the amount of ventilation provided to the indoor environment, did not vary much with particle size (ranged between 0.48 and 0.63 for the entire size range), and was similar for each period of the week (weekend vs. weekday, night vs. day). Regression analyses showed that ultrafine indoor PM baseline concentrations were higher at night from nighttime infiltration. A lag time was observed between outdoor and indoor measurements. Weekday days had the shortest lag time of 11 min, and weekend nighttime lags when the HVAC was not in use were 50 to 148 min. Indoor-outdoor PM concentration plots showed ultrafine PM was more correlated compared to fine, and especially when the HVAC system was on. Finally, AMS data showed that most of the PM was organic, with occasional nitrate events occurring outdoors. During nitrate events, there were less indoor particles detected, indicating a loss of particulate phase nitrate. The results from this study show that improved filtration is warranted in mechanically ventilated buildings, particularly for ultrafine particles, and that nighttime infiltration is significant depending on the building design.

  3. Initial ventilator settings for critically ill patients.

    Science.gov (United States)

    Kilickaya, Oguz; Gajic, Ognjen

    2013-03-12

    The lung-protective mechanical ventilation strategy has been standard practice for management of acute respiratory distress syndrome (ARDS) for more than a decade. Observational data, small randomized studies and two recent systematic reviews suggest that lung protective ventilation is both safe and potentially beneficial in patients who do not have ARDS at the onset of mechanical ventilation. Principles of lung-protective ventilation include: a) prevention of volutrauma (tidal volume 4 to 8 ml/kg predicted body weight with plateau pressurerespiratory rate 20 to 35 breaths per minute); and d) prevention of hyperoxia (titrate inspired oxygen concentration to peripheral oxygen saturation (SpO2) levels of 88 to 95%). Most patients tolerate lung protective mechanical ventilation well without the need for excessive sedation. Patients with a stiff chest wall may tolerate higher plateau pressure targets (approximately 35 cmH2O) while those with severe ARDS and ventilator asynchrony may require a short-term neuromuscular blockade. Given the difficulty in timely identification of patients with or at risk of ARDS and both the safety and potential benefit in patients without ARDS, lung-protective mechanical ventilation is recommended as an initial approach to mechanical ventilation in both perioperative and critical care settings.

  4. Effects of three approaches to standardized oral hygiene to reduce bacterial colonization and ventilator associated pneumonia in mechanically ventilated patients: a randomised control trial.

    Science.gov (United States)

    Berry, A M; Davidson, P M; Masters, J; Rolls, K; Ollerton, R

    2011-06-01

    Ventilator associated pneumonia remains an important concern in the intensive care unit (ICU). An increasing body of evidence shows that mortality and morbidity can be reduced by implementing a range of preventive strategies, including optimizing oral hygiene. The aim of this feasibility study was to test two oral hygiene strategies on the effects of microbial colonization of dental plaque with respiratory pathogens (primary outcome) and incidence of ventilator associated pneumonia (secondary outcome). A single blind randomised comparative study was conducted in a 20-bed adult intensive care unit in a university hospital. Patients with an expected duration of mechanical ventilation more than 48 h were eligible. Patients were randomised to one of three study regimens (Group A control, second hourly oral rinse with sterile water, Group B sodium bicarbonate mouth wash second hourly, and Group C twice daily irrigations with chlorhexidine 0.2% aqueous oral rinse and second hourly irrigations with sterile water). All study options included cleaning with a toothbrush and non foaming toothpaste. Data from a total of 109 patients were analyzed. Group A 43, Group B 33 and Group C 33 (mean age: 58 ± 17 years, simplified acute physiology score II: 44 ± 14 points). On admission no significant differences were found between groups for all clinical data. While Group B showed a greater trend to reduction in bacterial colonization no significant differences could be demonstrated at Day 4 of admission (p=0.302). The incidence of ventilator associated pneumonia was evenly spread between Groups B and C (5%) while Group A was only 1%. While a number of studies have advocated the use of various mouth rinses in reducing colonization of dental plaque a standardized oral hygiene protocol which includes the use of mechanical cleaning with a toothbrush may be a factor in the reduction of colonization of dental plaque with respiratory pathogens. This feasibility study provides data to

  5. A 17 year-old girl with a demyelinating disease requiring mechanical ventilation: a case report

    Directory of Open Access Journals (Sweden)

    Katsenos Chrysostomos

    2013-01-01

    Full Text Available Abstract Background Demyelinating diseases cause destruction of the myelin sheath, while axons are relatively spared. Pathologically, demyelination can be the result of an inflammatory process, viral infection, acquired metabolic derangement and ischemic insult. Three diseases that can cause inflammatory demyelination of the CNS are: Multiple sclerosis (MS, Acute disseminated encephalomyelitis (ADEM and Acute hemorrhagic leucoencephalitis. Differentiation is not always easy and there is considerable overlaping. Data about adults with acute demyelination requiring ICU admission is limited. Case presentation A 17 year old Greek female was hospitalised in the ICU because of acute respiratory failure requiring mechanical ventilation. She had a history of febrile disease one month before, acute onset of paraplegia, diplopia, progressive arm weakness and dyspnea. Her consciousness was not impaired. A demyelinating central nervous system (CNS disease, possibly post infectious encephalomyelitis (ADEM was the underlying condition. The MRI of the brain disclosed diffused expanded cerebral lesions involving the optic nerve, basal ganglia cerebellum, pons and medulla oblongata. There was also extended involvement of the cervical and thoracic part of the spinal cord. CSF leukocyte count was elevated with lymphocyte predominance. The patient required mechanical ventilation for two months. Then she was transferred to a rehabilitation centre. Three years later she remains paraplegic. Since then she has not suffered any other demyelination attack. Conclusions Demyelinating diseases can cause acute respiratory failure when the spinal cord is affected. Severe forms of these diseases, making necessary ICU admission, is less frequently reported. Intensivists should be aware of the features of these rare diseases.

  6. Timing of Tracheotomy in Mechanically Ventilated Critically Ill Morbidly Obese Patients

    Directory of Open Access Journals (Sweden)

    Ahmad Alhajhusain

    2014-01-01

    Full Text Available Background. The optimal timing of tracheotomy and its impact on weaning from mechanical ventilation in critically ill morbidly obese patients remain controversial. Methods. We conducted a retrospective chart review of morbidly obese subjects (BMI ≥ 40 kg/m2 or BMI ≥ 35 kg/m2 and one or more comorbid conditions who underwent a tracheotomy between July 2008 and June 2013 at a medical intensive care unit (ICU. Clinical characteristics, rates of nosocomial pneumonia (NP, weaning from mechanical ventilation (MV, and mortality rates were analyzed. Results. A total of 102 subjects (42 men and 60 women were included; their mean age and BMI were 56.3 ± 15.1 years and 53.3 ± 13.6 kg/m2, respectively. There was no difference in the rate of NP between groups stratified by successful weaning from MV (P=0.43. Mortality was significantly higher in those who failed to wean (P=0.02. A cutoff value of 9 days for the time to tracheotomy provided the best balanced sensitivity (72% and specificity (59.8% for predicting NP onset. Rates of NP and total duration of MV were significantly higher in those who had tracheostomy ≥ 9 days (P=0.004 and P=0.002, resp.. Conclusions. The study suggests that tracheotomy in morbidly obese subjects performed within the first 9 days may reduce MV and decrease NP but may not affect hospital mortality.

  7. The importance of knowing the patient in weaning from mechanical ventilation.

    Science.gov (United States)

    Crocker, Cheryl; Scholes, Julie

    2009-01-01

    The aim of the research was to understand how nurses used technology to wean patients from mechanical ventilation. The literature concerned with the development of critical care centres on the role of technology with little emphasis on the nursing contribution. An ethnographic approach was used to understand how nurses used technology to wean patients from mechanical ventilation. Data were gathered by participant observation and interviewing over a 6-month period. In total, 250 h of field notes were recorded. Data were analysed by the content analysis method. Knowing the patient was a central theme identified. Three sub-themes were identified: ways of knowing, continuity of care and the role of the patient in the weaning trajectory. 'Knowing the patient' was implied during the interviews as essential to the delivery of patient-centred care. There were two main factors that needed to be present in order for nurses to know their patients: continuity of care and expertise. 'Ways of knowing' was reliant on gaining information about the patient. The role of the patient was a passive recipient of treatment. Knowing the patient has been defined as a characteristic of expert nursing. To be truly patient-centred nursing needs to address the barriers that prevent nurses from getting to 'know' their patients.

  8. Reasons of PEG failure to eliminate gastroesophageal reflux in mechanically ventilated patients

    Institute of Scientific and Technical Information of China (English)

    Emmanuel E Douzinas; Ilias Andrianakis; Olga Livaditi; Dimitrios Bakos; Katerina Flevari; Nikos Goutas; Dimitrios Vlachodimitropoulos; Marios-Konstantinos Tasoulis; Alex P Betrosian

    2009-01-01

    AIM: To investigate factors predicting failure of percutaneous endoscopic gastrostomy (PEG) to eliminate gastroesophageal reflux (GER).METHODS: Twenty-nine consecutive mechanically ventilated patients were investigated.Patients were evaluated for GER by pH-metry pre-PEG and on the 7th post-PEG day.Endoscopic and histologic evidence of reflux esophagitis was also carried out.A beneficial response to PEG was considered when pH-metry on the 7th post-PEG day showed that GER was below 4%.RESULTS: Seventeen patients responded (RESP group) and 12 did not respond (N-RESP) to PEG.The mean age, sex, weight and APACHE Ⅱ score were similar in both groups.GER (%) values were similar in both groups at baseline, but were significantly reduced in the RESP group compared with the N-RESP group on the 7th post-PEG day [2.5 (0.6-3.8) vs 8.1 (7.4-9.2, P < 0.001)].Reflux esophagitis and the gastroesophageal flap valve (GEFV) grading differed significantly between the two groups ( P = 0.031 and P = 0.020, respectively).Histology revealed no significant differences between the two groups.CONCLUSION: Endoscopic grading of GEFV and the presence of severe reflux esophagitis are predisposing factors for failure of PEG to reduce GER in mechanically ventilated patients.

  9. The mechanism of olfactory organ ventilation in Periophthalmus barbarus (Gobiidae, Oxudercinae).

    Science.gov (United States)

    Kuciel, Michał

    2013-03-01

    Periophthalmus barbarus Linnaeus, 1766 has many adaptations for amphibious life as a consequence of tidal zone occupation. One of them is the ability to keep a little amount of water and air in mouth while on land or in hypoxic water, correlated with closing a gill lid for gas exchange improvement. It causes that mechanisms of olfactory organ ventilation described in other species of actinopterygians (compression of accessory nasal sac(s) by the skull and jaw elements while mouth and gill lid moving) are not in operation. There is a specific mechanism of olfactory organ ventilation independent on jaw and skull elements movements. Compression of accessory nasal sacs is possible by a0 contraction and it is a movement effect on bones combined by ligaments. This process can be observed on P. barbarus as lifting the rostral part of the head. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00435-012-0167-y) contains supplementary material, which is available to authorized users.

  10. Sedation of mechanically ventilated adults in intensive care unit: a network meta-analysis

    Science.gov (United States)

    Zhang, Zhongheng; Chen, Kun; Ni, Hongying; Zhang, Xiaoling; Fan, Haozhe

    2017-01-01

    Sedatives are commonly used for mechanically ventilated patients in intensive care units (ICU). However, a variety of sedatives are available and their efficacy and safety have been compared in numerous trials with inconsistent results. To resolve uncertainties regarding usefulness of these sedatives, we performed a systematic review and network meta-analysis. Randomized controlled trials comparing sedatives in mechanically ventilated ICU patients were included. Graph-theoretical methods were employed for network meta-analysis. A total of 51 citations comprising 52 RCTs were included in our analysis. Dexmedetomidine showed shorter MV duration than lorazepam (mean difference (MD): 68.7; 95% CI: 18.2–119.3 hours), midazolam (MD: 10.2; 95% CI: 7.7–12.7 hours) and propofol (MD: 3.4; 95% CI: 0.9–5.9 hours). Compared with dexmedetomidine, midazolam was associated with significantly increased risk of delirium (OR: 2.47; 95% CI: 1.17–5.19). Our study shows that dexmedetomidine has potential benefits in reducing duration of MV and lowering the risk of delirium. PMID:28322337

  11. Early versus late percutaneous dilational tracheostomy in critically ill patients anticipated requiring prolonged mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yue; LI Wen-xiong; SUI Feng; CHEN Xiu-kai; ZHANG Gui-chen; WANG Xiao-wen; ZHAO Song; SONG Yang; LIU Wei; XIN Xin

    2012-01-01

    Background Tracheostomy should be considered to replace endotracheal intubation in patients requiring prolonged mechanical ventilation (MV).However,the optimal timing for tracheostomy is still a topic of debate.The present study aimed to investigate whether early percutaneous dilational tracheostomy (PDT) can reduce duration of MV,and to further verify whether early PDT can reduce sedative use,shorten intensive care unit (ICU) stay,decrease the incidence of ventilator associated pneumonia (VAP),and increase successful weaning and ICU discharge rate.Methods A prospective,randomized controlled trial was carried out in a surgical ICU from July 2008 to June 2011 in adult patients anticipated requiring prolonged MV via endotracheal intubation.Patients meeting the inclusion criteria were randomly assigned to the early PDT group or the late PDT group on day 3 of MV.The patients in the early PDT group were tracheostomized with PDT on day 3 of MV.The patients in the late PDT group were tracheostomized with PDT on day 15 of MV if they still needed MV.The primary endpoint was ventilator-free days at day 28 after randomization.The secondary endpoints were sedation-free days,ICU-free days,successful weaning and ICU discharge rate,and incidence of VAP at day 28 after randomization.The cumulative 60-day incidence of death after randomization was also analyzed.Results Total 119 patients were randomized to either the early PDT group (n=58) or the late PDT group (n=61).The ventilator-free days was significantly increased in the early PDT group than in the late PDT group ((9.57±5.64) vs.(7.38±6.17) days,P <0.05).The sedation-free days and ICU-free days were also significantly increased in the early PDT group than in the late PDT group (20.84±2.35 vs.17.05±2.30 days,P <0.05; and 8.0 (interquartile range (IQR):5.0-12.0)vs.3.0 (IQR:0-12.0) days,P <0.001 respectively).The successful weaning and ICU discharge rate was significantly higher in early PDT group than in late PDT

  12. Noninvasive mechanical ventilation in high-risk pulmonary infections: a clinical review

    Directory of Open Access Journals (Sweden)

    Antonio M. Esquinas

    2014-12-01

    Full Text Available The aim of this article was to review the role of noninvasive ventilation (NIV in acute pulmonary infectious diseases, such as severe acute respiratory syndrome (SARS, H1N1 and tuberculosis, and to assess the risk of disease transmission with the use of NIV from patients to healthcare workers. We performed a clinical review by searching Medline and EMBASE. These databases were searched for articles on ‘‘clinical trials’’ and ‘‘randomised controlled trials’’. The keywords selected were non-invasive ventilation pulmonary infections, influenza-A (H1N1, SARS and tuberculosis. These terms were cross-referenced with the following keywords: health care workers, airborne infections, complications, intensive care unit and pandemic. The members of the International NIV Network examined the major results regarding NIV applications and SARS, H1N1 and tuberculosis. Cross-referencing mechanical ventilation with SARS yielded 76 studies, of which 10 studies involved the use of NIV and five were ultimately selected for inclusion in this review. Cross-referencing with H1N1 yielded 275 studies, of which 27 involved NIV. Of these, 22 were selected for review. Cross-referencing with tuberculosis yielded 285 studies, of which 15 involved NIV and from these seven were selected. In total 34 studies were selected for this review. NIV, when applied early in selected patients with SARS, H1N1 and acute pulmonary tuberculosis infections, can reverse respiratory failure. There are only a few reports of infectious disease transmission among healthcare workers.

  13. Mechanical ventilation strategies for intensive care unit patients without acute lung injury or acute respiratory distress syndrome: a systematic review and network meta-analysis

    OpenAIRE

    Guo, Lei; Wang, Weiwei; Zhao, Nana; Guo, Libo; Chi, Chunjie; Hou, Wei; Wu, Anqi; Tong, Hongshuang; Wang, Yue; Wang, Changsong; Li, Enyou

    2016-01-01

    Background It has been shown that the application of a lung-protective mechanical ventilation strategy can improve the prognosis of patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). However, the optimal mechanical ventilation strategy for intensive care unit (ICU) patients without ALI or ARDS is uncertain. Therefore, we performed a network meta-analysis to identify the optimal mechanical ventilation strategy for these patients. Methods We searched the Cochra...

  14. Non-invasive ventilation with intelligent volume-assured pressure support versus pressure-controlled ventilation: effects on the respiratory event rate and sleep quality in COPD with chronic hypercapnia.

    Science.gov (United States)

    Nilius, Georg; Katamadze, Nato; Domanski, Ulrike; Schroeder, Maik; Franke, Karl-Josef

    2017-01-01

    COPD patients who develop chronic hypercapnic respiratory failure have a poor prognosis. Treatment of choice, especially the best form of ventilation, is not well known. This study compared the effects of pressure-controlled (spontaneous timed [ST]) non-invasive ventilation (NIV) and NIV with intelligent volume-assured pressure support (IVAPS) in chronic hypercapnic COPD patients regarding the effects on alveolar ventilation, adverse patient/ventilator interactions and sleep quality. This prospective, single-center, crossover study randomized patients to one night of NIV using ST then one night with the IVAPS function activated, or vice versa. Patients were monitored using polysomnography (PSG) and transcutaneous carbon dioxide pressure (PtcCO2) measurement. Patients rated their subjective experience (total score, 0-45; lower scores indicate better acceptability). Fourteen patients were included (4 females, age 59.4±8.9 years). The total number of respiratory events was low, and similar under pressure-controlled (5.4±6.7) and IVAPS (8.3±10.2) conditions (P=0.064). There were also no clinically relevant differences in PtcCO2 between pressure-controlled and IVAPS NIV (52.9±6.2 versus 49.1±6.4 mmHg). Respiratory rate was lower under IVAPS overall; between-group differences reached statistical significance during wakefulness and non-rapid eye movement sleep. Ventilation pressures were 2.6 cmH2O higher under IVAPS versus pressure-controlled ventilation, resulting in a 20.1 mL increase in breathing volume. Sleep efficiency was slightly higher under pressure-controlled ventilation versus IVAPS. Respiratory arousals were uncommon (24.4/h [pressure-controlled] versus 25.4/h [IVAPS]). Overall patient assessment scores were similar, although there was a trend toward less discomfort during IVAPS. Our results show that IVAPS NIV allows application of higher nocturnal ventilation pressures versus ST without affecting sleep quality or inducing ventilation- associated events.

  15. Non-invasive ventilation with intelligent volume-assured pressure support versus pressure-controlled ventilation: effects on the respiratory event rate and sleep quality in COPD with chronic hypercapnia

    Directory of Open Access Journals (Sweden)

    Nilius G

    2017-03-01

    Full Text Available Georg Nilius,1,2 Nato Katamadze,1,2 Ulrike Domanski,1 Maik Schroeder,1 Karl-Josef Franke1,2 1HELIOS Klinik Hagen-Ambrock, 2Internal Medicine I, Witten/Herdecke University, Witten, Germany Background: COPD patients who develop chronic hypercapnic respiratory failure have a poor prognosis. Treatment of choice, especially the best form of ventilation, is not well known. Objectives: This study compared the effects of pressure-controlled (spontaneous timed [ST] non-invasive ventilation (NIV and NIV with intelligent volume-assured pressure support (IVAPS in chronic hypercapnic COPD patients regarding the effects on alveolar ventilation, adverse patient/ventilator interactions and sleep quality. Methods: This prospective, single-center, crossover study randomized patients to one night of NIV using ST then one night with the IVAPS function activated, or vice versa. Patients were monitored using polysomnography (PSG and transcutaneous carbon dioxide pressure (PtcCO2 measurement. Patients rated their subjective experience (total score, 0–45; lower scores indicate better acceptability. Results: Fourteen patients were included (4 females, age 59.4±8.9 years. The total number of respiratory events was low, and similar under pressure-controlled (5.4±6.7 and IVAPS (8.3±10.2 conditions (P=0.064. There were also no clinically relevant differences in PtcCO2 between pressure-controlled and IVAPS NIV (52.9±6.2 versus 49.1±6.4 mmHg. Respiratory rate was lower under IVAPS overall; between-group differences reached statistical significance during wakefulness and non-rapid eye movement sleep. Ventilation pressures were 2.6 cmH2O higher under IVAPS versus pressure-controlled ventilation, resulting in a 20.1 mL increase in breathing volume. Sleep efficiency was slightly higher under pressure-controlled ventilation versus IVAPS. Respiratory arousals were uncommon (24.4/h [pressure-controlled] versus 25.4/h [IVAPS]. Overall patient assessment scores were similar

  16. System identification and closed-loop control of end-tidal CO2 in mechanically ventilated patients.

    Science.gov (United States)

    Hahn, Jin-Oh; Dumont, Guy A; Anersmino, J Mark

    2012-11-01

    This paper presents a systematic approach to system identification and closed-loop control of end-tidal carbon dioxide partial pressure (PETCO2) in mechanically ventilated patients. An empirical model consisting of a linear dynamic system followed by an affine transform is proposed to derive a low-order and high-fidelity representation that can reproduce the positive and inversely proportional dynamic input-output relationship between PETCO2 and minute ventilation (MV) in mechanically ventilated patients. The predictive capability of the empirical model was evaluated using experimental respiratory data collected from eighteen mechanically ventilated human subjects. The model predicted PETCO2 response accurately with a root-mean-squared error (RMSE) of 0.22+/-0.16 mmHg and a coefficient of determination (r2) of 0.81+/-0.18 (mean+/-SD) when a second-order rational transfer function was used as its linear dynamic component. Using the proposed model, a closedloop control method for PETCO2 based on a proportionalintegral (PI) compensator was proposed by systematic analysis of the system root locus. For the eighteen mechanically ventilated patient models identified, the PI compensator exhibited acceptable closed-loop response with a settling time of 1.27+/- 0.20 min and a negligible overshoot (0.51+/-1.17%), in addition to zero steady-state PETCO2 set point tracking. The physiologic implication of the proposed empirical model was analyzed by comparing it with the traditional multi-compartmental model widely used in pharmacological modeling.

  17. Effect of ultra-fast mild hypothermia using total liquid ventilation on hemodynamics and respiratory mechanics.

    Science.gov (United States)

    Sage, Michaël; Nadeau, Mathieu; Kohlhauer, Matthias; Praud, Jean-Paul; Tissier, Renaud; Robert, Raymond; Walti, Hervé; Micheau, Philippe

    2016-08-01

    Ultra-fast cooling for mild therapeutic hypothermia (MTH) has several potential applications, including prevention of post-cardiac arrest syndrome. Ultra-fast MTH by total liquid ventilation (TLV) entails the sudden filling of the lungs with a cold perfluorocarbon liquid and its subsequent use to perform TLV. The present physiological study was aimed at assessing whether pulmonary and systemic hemodynamics as well as lung mechanics are significantly altered during this procedure. Pulmonary and systemic arterial pressures, cardiac output as well as airway resistance and respiratory system compliance were measured during ultra-fast MTH by TLV followed by rewarming and normothermia in six healthy juvenile lambs. Results show that none of the studied variables were altered upon varying the perfluorocarbon temperature from 12 to 41 °C. It is concluded that ultra-fast MTH by TLV does not have any deleterious effect on hemodynamics or lung mechanics in healthy juvenile lambs.

  18. Design Principles for Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system -Hybrid Ventilation....... The hybrid ventilation concepts, design challenges and - principles are discussed and illustrated by four building examples....

  19. 高容量血液滤过联合机械通气对犬海水型呼吸窘迫综合征的作用%Effect of high volume hemofiltration combined with mechanical ventilation on seawater respiratory distress syndrome in canine models

    Institute of Scientific and Technical Information of China (English)

    肖达平; 陈光明; 林华铿; 何金选; 陈建

    2011-01-01

    mABP、HR、CVP无显著影响.%Objective To investigate the effect of high volume hemofiltration (HVHF) combined with mechanical ventilation (MV) on seawater respiratory distress syndrome (SW-RDS) canine models. Methods Ten nomal hybrid dogs were randomly assigned into two groups:MV group (MV group,n=5),all the animals only received MV after establishing model successfully; HVHF combined with MV group (HVHF+MV group,n=5),all were received HVHF plus MV after establishing model successfully.Both groups were observed for 4 hours.Mean arterial pressure (MAP),heart rate (HR),central venous pressure (CVP),arterial blood gas and venous plasma osmotic pressure were detected at baseline,0 min (model establishment),60 min,120 min,180 min,240min after treatment.Venous blood was collected to detect inflammatory mediators (IL-8,IL-6,TNF-α)at baseline,0 min,120 min,240 min after treatment.The lung pathology was examined at the end of the experiment. Results (1)All the animals were suvival after four hous of treatment in both groups. (2)Pattial pressure ofoxygen (PaO2) and O2 saturation (SaO2) rised after four hours of treatment in both groups (P<0.05), and HVHF+MV group was better than MV group.After 4 hours of treatment,pH,actual bicarbonate (AB),bases excess (BE) in HVHF+MV group were significantly better than those in MV group (P<0.05),recovering to the baseline values.(3)MAP,HR,CVP were stable during the four hours of treatment,and compared with 0 min,there was no significant differences after 4 hours of treatment in both groups. There were no significant differemces at the same time of treatment in both groups. (4)Plasma osmotic pressure were stable during the four hours of treatment,and compared with 0 min,there was no significant difference in MV group.But in HVHF+MV group,osmotic pressure was significantly higher after 4 hours of treatment than that at the same time in MV group (P<0.05),and compared with 0 min and 180 min,those were higher too (P<0.01). (5)Compared with those at the same time in MV group

  20. Review of Residential Ventilation Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Armin Rudd

    2005-08-30

    This paper reviews current and potential ventilation technologies for residential buildings, including a variety of mechanical systems, natural ventilation, and passive ventilation. with particular emphasis on North American climates and construction.

  1. The effects of open lung ventilation on respiratory mechanics and haemodynamics in atelectatic infants after cardiopulmonary bypass.

    Science.gov (United States)

    Cui, Q; Zhou, H; Zhao, R; Liu, J; Yang, X; Zhu, H; Zheng, Q; Gu, C; Yi, D

    2009-01-01

    Acute lung injury (ALI) frequently occurs in infants after cardiopulmonary bypass (CPB) surgery and it sometimes develops into acute respiratory distress syndrome in critically ill infants, which can be life threatening. This study investigated the effects of open lung ventilation on the haemodynamics and respiratory mechanics of 64 infants (34 males; 30 females) with a mean +/- SD age of 8.3 +/- 0.3 months who developed ALI following CPB surgery. Open lung ventilation significantly improved the respiratory mechanics and oxygenation parameters of the infants, including the partial pressure of oxygen in arterial blood (PaO(2)), the ratio of PaO(2)/FiO(2) (fraction of inspired oxygen), peak inspiratory pressure, static compliance and airway resistance. It is concluded that open lung ventilation can greatly improve oxygenation and respiratory mechanics in infants with ALI following CPB surgery.

  2. A novel preterm respiratory mechanics active simulator to test the performances of neonatal pulmonary ventilators

    Science.gov (United States)

    Cappa, Paolo; Sciuto, Salvatore Andrea; Silvestri, Sergio

    2002-06-01

    A patient active simulator is proposed which is capable of reproducing values of the parameters of pulmonary mechanics of healthy newborns and preterm pathological infants. The implemented prototype is able to: (a) let the operator choose the respiratory pattern, times of apnea, episodes of cough, sobs, etc., (b) continuously regulate and control the parameters characterizing the pulmonary system; and, finally, (c) reproduce the attempt of breathing of a preterm infant. Taking into account both the limitation due to the chosen application field and the preliminary autocalibration phase automatically carried out by the proposed device, accuracy and reliability on the order of 1% is estimated. The previously indicated value has to be considered satisfactory in light of the field of application and the small values of the simulated parameters. Finally, the achieved metrological characteristics allow the described neonatal simulator to be adopted as a reference device to test performances of neonatal ventilators and, more specifically, to measure the time elapsed between the occurrence of a potentially dangerous condition to the patient and the activation of the corresponding alarm of the tested ventilator.

  3. Personal care assistants' experiences of caring for people on home mechanical ventilation.

    Science.gov (United States)

    Israelsson-Skogsberg, Åsa; Lindahl, Berit

    2017-03-01

    The aim of this study was to describe personal care assistants' (PCA) experiences of working with a ventilator-assisted person at home. Data were collected from fifteen audiotaped semistructured interviews with PCAs supporting a child or adult using home mechanical ventilation (HMV). Thirteen women and two men participated; their working experience with HMV users ranged from one to 17 years (median 6 years). Data were subjected to qualitative content analysis in an inductive and interpretive manner. Five categories emerged from the data: Being part of a complex work situation; Taking on a multidimensional responsibility; Caring carried out in someone's home; Creating boundaries in an environment with indistinct limits; and Being close to another's body and soul. The participants felt very close to the person they worked with, both physically and emotionally. They had a great responsibility and therefore a commensurate need for support, guidance and a well-functioning organisation around the HMV user. There is international consensus that advanced home care will continue to expand and personal care assistance is key in this development. We suggest that one way to move forward for PCAs working with HMV users is to create multiprofessional teams led by a key-person who coordinates the individual needs. More research is needed within this area from a broad perspective including the HMV-assisted persons, relatives, personal care assistants and management organisations. © 2016 Nordic College of Caring Science.

  4. Cardiorespiratory Mechanical Simulator for In Vitro Testing of Impedance Minute Ventilation Sensors in Cardiac Pacemakers.

    Science.gov (United States)

    Marcelli, Emanuela; Cercenelli, Laura

    2016-01-01

    We developed a cardiorespiratory mechanical simulator (CRMS), a system able to reproduce both the cardiac and respiratory movements, intended to be used for in vitro testing of impedance minute ventilation (iMV) sensors in cardiac pacemakers. The simulator consists of two actuators anchored to a human thorax model and a software interface to control the actuators and to acquire/process impedance signals. The actuators can be driven separately or simultaneously to reproduce the cardiac longitudinal shortening at a programmable heart rate and the diaphragm displacement at a programmable respiratory rate (RR). A standard bipolar pacing lead moving with the actuators and a pacemaker case fixed to the thorax model have been used to measure impedance (Z) variations during the simulated cardiorespiratory movements. The software is able to discriminate the low-frequency component because of respiration (Z(R)) from the high-frequency ripple because of cardiac effect (Z(C)). Impedance minute ventilation is continuously calculated from Z(R) and RR. From preliminary tests, the CRMS proved to be a reliable simulator for in vitro evaluation of iMV sensors. Respiration impedance recordings collected during cardiorespiratory movements reproduced by the CRMS were comparable in morphology and amplitude with in vivo assessments of transthoracic impedance variations.

  5. Role of mechanical ventilation in the airborne transmission of infectious agents in buildings.

    Science.gov (United States)

    Luongo, J C; Fennelly, K P; Keen, J A; Zhai, Z J; Jones, B W; Miller, S L

    2016-10-01

    Infectious disease outbreaks and epidemics such as those due to SARS, influenza, measles, tuberculosis, and Middle East respiratory syndrome coronavirus have raised concern about the airborne transmission of pathogens in indoor environments. Significant gaps in knowledge still exist regarding the role of mechanical ventilation in airborne pathogen transmission. This review, prepared by a multidisciplinary group of researchers, focuses on summarizing the strengths and limitations of epidemiologic studies that specifically addressed the association of at least one heating, ventilating and/or air-conditioning (HVAC) system-related parameter with airborne disease transmission in buildings. The purpose of this literature review was to assess the quality and quantity of available data and to identify research needs. This review suggests that there is a need for well-designed observational and intervention studies in buildings with better HVAC system characterization and measurements of both airborne exposures and disease outcomes. Studies should also be designed so that they may be used in future quantitative meta-analyses.

  6. The decrease of cardiac chamber volumes and output during positive-pressure ventilation

    DEFF Research Database (Denmark)

    Kristensen, Kasper Kyhl; Ahtarovski, Kiril Aleksov; Iversen, Kasper

    2013-01-01

    the effect of PPV on the central circulation by studying cardiac chamber volumes with cardiac magnetic resonance imaging (CMR). We hypothesized that PPV lowers cardiac output (CO) mainly via the Frank-Starling relationship. In 18 healthy volunteers, cardiac chamber volumes and flow in aorta and the pulmonary...

  7. Weaning infants with respiratory syncytial virus from mechanical ventilation through a fuzzy-logic controller.

    Science.gov (United States)

    Olliver, S; Davis, G M; Hatzakis, G E

    2003-01-01

    We have previously developed a fuzzy logic controller for weaning adults with chronic obstructive pulmonary disease using pressure support ventilation (PSV). We used the core of our fuzzy logic-based weaning platform and further developed parametrizable components for weaning newborns of differing body size and disease-state. The controller was validated on neonates recovering from congenital heart disease (CHD) while receiving synchronous intermittent mandatory ventilation (SIMV). We wished to compare the efficacy of this controller versus the bedside weaning protocol in children with respiratory syncytial virus pneumonitis/bronchiolitis (RSV) in the pediatric intensive care unit (PICU). The fuzzy controller evaluated the "current" and "trend" weaning status of the newborn to quantitatively determine the change in the SIMV integrated ventilatory setting. For the "current" status it used heart rate (HR), respiratory rate (RR), tidal volume (VT) and oxygen saturation (SaO2), while for the "trend" status the differences of deltaRR/ deltat, deltaHR/ deltat, and deltaSaO2/ deltat recorded between two subsequent time points were utilized. The enumerated vital signs were fuzzified and then probability levels of occurrence were assigned. Individualized "golden" goals for SaO2 were set for each newborn. We retrospectively assessed the charts of 19 newborns, 113+/-128 days old, 5,546+/-2,321 gr body weight, weaning for 99+/-46 days, at 2-hour intervals. The SIMV levels proposed by the fuzzy controller were matched to those levels actually applied. In 60% of the time both values coincided. For the remaining 40%, the controller was more aggressive suggesting lower values of SIMV than the applied ones. The Area under the SIMV curves over time was 1,969+/-1,044 for the applied vs 1,886+/-978 for the suggested levels, respectively. The fuzzy controller adjusted for body size and disease-pattern can approximate the actual weaning course of newborns with RSV.

  8. The clinical value of dexmedetomidine during mechanical ventilation in ICU patients of different ages

    Directory of Open Access Journals (Sweden)

    Yan ZHU

    2015-10-01

    Full Text Available Objectives To provide basis for the safe use of indigenous dexmedetomidine hydrochloride by observing its sedative effect and safety when it was given to mechanically ventilated patients of different ages. Methods Three hundred and fourteen mechanically ventilated patients were admitted to our ICU. According to the age, patients were divided into two subgroups: group A (25-50 years old and group B (51-80 years old, with 157 patients in each group. Dexmedetomidine was given to achieve the target sedation level (Ramsay score 3. The changes in noninvasive blood pressure (SBP, DBP, MAP, heart rate, SpO2, respiratory rate and FiO2 were continuously monitored and recorded before treatment (T1, and 10min (T2, 30min (T3 and 120min (T4 after drug administration, on the instant moment of extubation (T5, and 30min after extubation (T6. The adverse reactions such as hypertension, hypotension, bradycardia, tachycardia, delirium were also observed and recorded after treatment. Results Patients of both A and B groups showed a lowering of SBP, DBP, MAP and HR after treatment with dexmedetomidine, especially in group B(P80mmHg, HR>60 times/min. Respiratory rate was reduced (P0.05. SpO2 was not reduced, and it even rose 30min after administration of dexmedetomidine (P0.05, and the heart rate was slightly slower in group B (P<0.05. The probability of occurrence of adverse reactions, such as hypertension, hypotension, tachycardia, bradycardia and delirium was significantly higher in group B than in group A. Conclusions Dexmedetomidine does not depress respiration, and a stable hemodynamics was maintained after extubation in ICU patients undergoing mechanical ventilation, thus it is an ideal sedative drug. But when it is used in elderly patients, proper monitoring should be maintained, especially when a loading dose is used, in order to prevent adverse reactions such as hypotension and bradycardia, and should be corrected in time. DOI: 10.11855/j.issn.0577-7402.2015.09.15

  9. Unmasking of tracheomalacia following short-term mechanical ventilation in a patient of adult respiratory distress syndrome

    Directory of Open Access Journals (Sweden)

    Harihar V Hegde

    2012-01-01

    Full Text Available Patients with chronic obstructive pulmonary disease (COPD are susceptible to airway malacia, which may be unmasked following mechanical ventilation or tracheostomy decannulation. Dynamic imaging of central airways, a non-invasive test as effective as bronchoscopy to diagnose airway malacia, has increased the recognition of this disorder. We describe a 70-year-old woman admitted with adult respiratory distress syndrome. She had cardiorespiratory arrest on admission, from which she was successfully resuscitated. She had obesity, hypertension, diabetes mellitus, recurrent ventricular tachycardia, sarcoidosis with interstitial lung disease and COPD. She received short-term (18 days mechanical ventilation with tracheostomy and developed respiratory distress following tracheostomy decannulation.

  10. Mechanical Ventilation Weaning in Inclusion Body Myositis: Feasibility of Isokinetic Inspiratory Muscle Training as an Adjunct Therapy

    Directory of Open Access Journals (Sweden)

    Leonardo Cordeiro de Souza

    2014-01-01

    Full Text Available Inclusion body myositis is a rare myopathy associated with a high rate of respiratory complications. This condition usually requires prolonged mechanical ventilation and prolonged intensive care stay. The unsuccessful weaning is mainly related to respiratory muscle weakness that does not promptly respond to immunosuppressive therapy. We are reporting a case of a patient in whom the use of an inspiratory muscle-training program which started after a two-week period of mechanical ventilation was associated with a successful weaning in one week and hospital discharge after 2 subsequent weeks.

  11. Lipid metabolism disturbances and AMPK activation in prolonged propofol-sedated rabbits under mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    Wei JIANG; Zheng-bo YANG; Quan-hong ZHOU; Xiang HUAN; Li WANG

    2012-01-01

    To explore the mechanisms underlying the propofol infusion syndrome (PRIS),a potentially fatal complication during prolonged propofol infusion.Methods:Male rabbits urider mechanical ventilation through endotracheal intubation were divided into 3 groups (n=6 for each) that were sedated with 1% propofol (Group P),isoflurane (Group Ⅰ) or isoflurane while receiving 10% intralipid (Group Ⅱ),respectively.Blood biochemical parameters were collected at O,6,12,18,24,and 30-36 h after the initiation of treatments.The hearts were removed out immediately after the experiments,and the level of tumor necrosis factor (TNF)-α in the hearts were studied using immunohistochemistry.AMP-activated protein kinase (AMPK) and phospho-AMPK in the hearts were assessed using Western blotting.Results:The mortality rate was 50% in Group P,and 0% in Groups Ⅰ and Ⅱ.The serum lipids and liver function indices in Group P were significantly increased,but moderately increased in Group Ⅱ.Significant decreases in these indices were found in Groups Ⅰ.All the groups showed dramatically increased release of creatine kinase (CK).Intense positive staining of TNF-c was found in all the heart samples in Group P,but only weak and neglectful staining was found in the hearts from Group Ⅱ and Group Ⅰ,respectively.AMPK phosphorylation was significantly increased in the hearts of Group P.Conclusion:Continuous infusion of large dose of propofol in rabbits undergoing prolonged mechanical ventilation causes hyperlipidemia,liver dysfunction,increased CK levels,AMPK activation and myocardial injury.The imbalance between energy demand and utilization may contribute to PRIS.

  12. Ventilação mecânica no intra-operatório Intraoperative mechanical ventilation

    Directory of Open Access Journals (Sweden)

    José Otávio Costa Auler Junior

    2007-09-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Em 2000, foi publicado o II Consenso Brasileiro de Ventilação Mecânica. Desde então, o conhecimento na área da ventilação mecânica avançou rapidamente, com a publicação de inúmeros estudos clínicos que acrescentaram informações importantes para o manuseio de pacientes críticos em ventilação artificial. Além disso, a expansão do conceito de Medicina Baseada em Evidências determinou a hierarquização das recomendações clínicas, segundo o rigor do método dos estudos que os embasaram. Essa abordagem explícita vem ampliando a compreensão e a aplicação das recomendações clínicas. Por esses motivos, a AMIB - Associação de Medicina Intensiva Brasileira - e a SBPT - Sociedade Brasileira de Pneumologia e Tisiologia - julgaram conveniente a atualização das recomendações descritas no Consenso anterior. Dentre os tópicos selecionados a Ventilação Mecânica no Intra-Operatório foi um dos temas propostos. O objetivo foi descrever os pontos mais importantes relacionados à ventilação mecânica no período intra-operatório. MÉTODO: Objetivou-se chegar a um documento suficientemente sintético, que refletisse a melhor evidência disponível na literatura. A revisão bibliográfica baseou-se na busca de estudos através de palavras-chave e em sua gradação conforme níveis de evidência. As palavras-chave utilizadas para a busca foram: mechanical ventilation, perioperative e anesthesia. RESULTADOS: São apresentadas recomendações quanto à prevenção de complicações, as modalidades ventilatórias que podem ser aplicadas durante a anestesia e as manobras pós-operatórias para aumento do volume pulmonar. CONCLUSÕES: A atelectasia pulmonar tem se mostrado uma complicação freqüente no intra-operatório, assim técnicas de ventilação mecânica têm sido introduzidas visando a redução nessas complicações.BACKGROUND AND OBJECTIVES: The II Brazilian Consensus Conference on

  13. An Official American Thoracic Society/American College of Chest Physicians Clinical Practice Guideline: Liberation from Mechanical Ventilation in Critically Ill Adults. Rehabilitation Protocols, Ventilator Liberation Protocols, and Cuff Leak Tests.

    Science.gov (United States)

    Girard, Timothy D; Alhazzani, Waleed; Kress, John P; Ouellette, Daniel R; Schmidt, Gregory A; Truwit, Jonathon D; Burns, Suzanne M; Epstein, Scott K; Esteban, Andres; Fan, Eddy; Ferrer, Miguel; Fraser, Gilles L; Gong, Michelle Ng; Hough, Catherine L; Mehta, Sangeeta; Nanchal, Rahul; Patel, Sheena; Pawlik, Amy J; Schweickert, William D; Sessler, Curtis N; Strøm, Thomas; Wilson, Kevin C; Morris, Peter E

    2017-01-01

    Interventions that lead to earlier liberation from mechanical ventilation can improve patient outcomes. This guideline, a collaborative effort between the American Thoracic Society and the American College of Chest Physicians, provides evidence-based recommendations to optimize liberation from mechanical ventilation in critically ill adults. Two methodologists performed evidence syntheses to summarize available evidence relevant to key questions about liberation from mechanical ventilation. The methodologists appraised the certainty in the evidence (i.e., the quality of evidence) using the Grading of Recommendations, Assessment, Development, and Evaluation approach and summarized the results in evidence profiles. The guideline panel then formulated recommendations after considering the balance of desirable consequences (benefits) versus undesirable consequences (burdens, adverse effects, and costs), the certainty in the evidence, and the feasibility and acceptability of various interventions. Recommendations were rated as strong or conditional. The guideline panel made four conditional recommendations related to rehabilitation protocols, ventilator liberation protocols, and cuff leak tests. The recommendations were for acutely hospitalized adults mechanically ventilated for more than 24 hours to receive protocolized rehabilitation directed toward early mobilization, be managed with a ventilator liberation protocol, be assessed with a cuff leak test if they meet extubation criteria but are deemed high risk for postextubation stridor, and be administered systemic steroids for at least 4 hours before extubation if they fail the cuff leak t