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Sample records for airway pressure breathing

  1. Comparison of nasal continuous positive airway pressure delivered by seven ventilators using simulated neonatal breathing.

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    Drevhammar, Thomas; Nilsson, Kjell; Zetterström, Henrik; Jonsson, Baldvin

    2013-05-01

    Nasal continuous positive airway pressure (NCPAP) is an established treatment for respiratory distress in neonates. Most modern ventilators are able to provide NCPAP. There have been no large studies examining the properties of NCPAP delivered by ventilators. The aim of this study was to compare pressure stability and imposed work of breathing (iWOB) for NCPAP delivered by ventilators using simulated neonatal breathing. Experimental in vitro study. Research laboratory in Sweden. None. Neonatal breathing was simulated using a mechanical lung simulator. Seven ventilators were tested at different CPAP levels using two breath profiles. Pressure stability and iWOB were determined. Results from three ventilators revealed that they provided a slight pressure support. For these ventilators, iWOB could not be calculated. There were large differences in pressure stability and iWOB between the tested ventilators. For simulations using the 3.4-kg breath profile, the pressure swings around the mean pressure were more than five times greater, and iWOB more than four times higher, for the system with the highest measured values compared with the system with the lowest. Overall, the Fabian ventilator was the most pressure stable system. Evita XL and SERVO-i were found more pressure stable than Fabian in some simulations. The results for iWOB were in accordance with pressure stability for systems that allowed determination of this variable. Some of the tested ventilators unexpectedly provided a minor degree of pressure support. In terms of pressure stability, we have not found any advantages of ventilators as a group compared with Bubble CPAP, Neopuff, and variable flow generators that were tested in our previous study. The variation between individual systems is great within both categories. The clinical importance of these findings needs further investigation.

  2. Treatment of sleep-disordered breathing with positive airway pressure devices: technology update.

    Science.gov (United States)

    Johnson, Karin Gardner; Johnson, Douglas Clark

    2015-01-01

    Many types of positive airway pressure (PAP) devices are used to treat sleep-disordered breathing including obstructive sleep apnea, central sleep apnea, and sleep-related hypoventilation. These include continuous PAP, autoadjusting CPAP, bilevel PAP, adaptive servoventilation, and volume-assured pressure support. Noninvasive PAP has significant leak by design, which these devices adjust for in different manners. Algorithms to provide pressure, detect events, and respond to events vary greatly between the types of devices, and vary among the same category between companies and different models by the same company. Many devices include features designed to improve effectiveness and patient comfort. Data collection systems can track compliance, pressure, leak, and efficacy. Understanding how each device works allows the clinician to better select the best device and settings for a given patient. This paper reviews PAP devices, including their algorithms, settings, and features.

  3. Work of breathing as a tool to diagnose severe fixed upper airway obstruction.

    Science.gov (United States)

    Khirani, S; Pierrot, S; Leboulanger, N; Ramirez, A; Breton, D; Couloigner, V; Fauroux, B

    2014-03-01

    A 4-year-old girl with bilateral vocal fold palsy was successfully decannulated from tracheotomy after seven laryngeal procedures. But an important stridor and dyspnea recurred 13 months after decannulation. Nocturnal gas exchange was normal but her daytime work of breathing was increased by fourfold, without any beneficial effect of nasal noninvasive continuous positive airway pressure ventilation (CPAP), reflecting a severe fixed airway obstruction. Endoscopic examination confirmed the work of breathing findings showing glottic and supraglottic stenosis. This upper airway obstruction was successfully treated with a recannulation. In conclusion, the major message of this case report is that measurement of the work of breathing was able to document the "fixed" nature of the airway obstruction, by showing no improvement even with highest tolerated levels of nasal CPAP. As such, the work of breathing may be proposed as a screening tool to quantify and assess the reversibility of severe upper airway obstruction in children. © 2013 Wiley Periodicals, Inc.

  4. The role of arterial chemoreceptors in the breath-by-breath augmentation of inspiratory effort in rabbits during airway occlusion or elastic loading.

    Science.gov (United States)

    Callanan, D; Read, D J

    1974-08-01

    1. The breath-by-breath augmentation of inspiratory effort in the five breaths following airway occlusion or elastic loading was assessed in anaesthetized rabbits from changes of airway pressure, diaphragm e.m.g. and lung volume.2. When the airway was occluded in animals breathing air, arterial O(2) tension fell by 20 mmHg and CO(2) tension rose by 7 mmHg within the time of the first five loaded breaths.3. Inhalation of 100% O(2) or carotid denervation markedly reduced the breath-by-breath progression but had little or no effect on the responses at the first loaded breath.4. These results indicate that the breath-by-breath augmentation of inspiratory effort following addition of a load is mainly due to asphyxial stimulation of the carotid bodies, rather than to the gradual emergence of a powerful load-compensating reflex originating in the chest-wall, as postulated by some workers.5. The small residual progression seen in animals breathing 100% O(2) or following carotid denervation was not eliminated (a) by combining these procedures or (b) by addition of gas to the lungs to prevent the progressive lung deflation which occurred during airway occlusion.6. Bilateral vagotomy, when combined with carotid denervation, abolished the residual breath-by-breath progression of inspiratory effort.

  5. Treatment of sleep-disordered breathing with positive airway pressure devices: technology update

    Directory of Open Access Journals (Sweden)

    Johnson KG

    2015-10-01

    Full Text Available Karin Gardner Johnson, Douglas Clark Johnson Department of Medicine, Baystate Medical Center, Springfield, MA, USA Abstract: Many types of positive airway pressure (PAP devices are used to treat sleep-disordered breathing including obstructive sleep apnea, central sleep apnea, and sleep-related hypoventilation. These include continuous PAP, autoadjusting CPAP, bilevel PAP, adaptive servoventilation, and volume-assured pressure support. Noninvasive PAP has significant leak by design, which these devices adjust for in different manners. Algorithms to provide pressure, detect events, and respond to events vary greatly between the types of devices, and vary among the same category between companies and different models by the same company. Many devices include features designed to improve effectiveness and patient comfort. Data collection systems can track compliance, pressure, leak, and efficacy. Understanding how each device works allows the clinician to better select the best device and settings for a given patient. This paper reviews PAP devices, including their algorithms, settings, and features. Keywords: BiPAP, CPAP, iVAPS, AVAPS, ASV, positive pressure respiration, instrumentation, treatment algorithm

  6. Pressure breathing in fighter aircraft for G accelerations and loss of cabin pressurization at altitude--a brief review.

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    Lauritzsen, Lars P; Pfitzner, John

    2003-04-01

    The purpose of this brief review is to outline the past and present use of pressure breathing, not by patients but by fighter pilots. Of the historical and recent references quoted, most are from aviation-medicine journals that are not often readily available to anesthesiologists. Pressure breathing at moderate levels of airway pressure gave World War II fighter pilots a tactical altitude advantage. With today's fast and highly maneuverable jet fighters, very much higher airway pressures of the order of 8.0 kPa (identical with 60 mmHg) are used. They are used in conjunction with a counterpressure thoracic vest and an anti-G suit for the abdomen and lower body. Pressurization is activated automatically in response to +Gz accelerations, and to a potentially catastrophic loss of cabin pressurization at altitude. During +Gz accelerations, pressure breathing has been shown to maintain cerebral perfusion by raising the systemic arterial pressure, so increasing the level of G-tolerance that is afforded by the use of anti-G suits and seat tilt-back angles alone. This leaves the pilot less reliant on rigorous, and potentially distracting, straining maneuvers. With loss of cabin pressurization at altitude, pressure breathing of 100% oxygen at high airway pressures enables the pilot's alveolar PO(2) to be maintained at a safe level during emergency descent. Introduced in military aviation, pressure breathing for G-tolerance and pressure breathing for altitude presented as concepts that may be of general physiological interest to many anesthesiologists.

  7. Increased airway reactivity in a neonatal mouse model of Continuous Positive Airway Pressure (CPAP)

    OpenAIRE

    Mayer, Catherine A.; Martin, Richard J.; MacFarlane, Peter M.

    2015-01-01

    Background Continuous positive airway pressure (CPAP) is a primary form of respiratory support used in the intensive care of preterm infants, but its long-term effects on airway (AW) function are unknown. Methods We developed a neonatal mouse model of CPAP treatment to determine whether it modifies later AW reactivity. Un-anesthetized spontaneously breathing mice were fitted with a mask to deliver CPAP (6cmH2O, 3hrs/day) for 7 consecutive days starting at postnatal day 1. Airway reactivity to...

  8. COMPARISON OF 3 NORMAL BREATHING TECHNIQUES TO ASSESS REVERSIBILITY OF AIRWAY-OBSTRUCTION

    NARCIS (Netherlands)

    GIMENO, F; POSTMA, DS; VANALTENA, R

    1992-01-01

    Measurement of forced expiratory volume in one second (FEV1) is generally used to assess airway obstruction. Function tests during normal breathing are used as complementary tests as well as alternatives. Studies have been done comparing the esophageal pressure method with body plethysmography, and

  9. Effects of Depth of Propofol and Sevoflurane Anesthesia on Upper Airway Collapsibility, Respiratory Genioglossus Activation, and Breathing in Healthy Volunteers

    DEFF Research Database (Denmark)

    Simons, Jeroen C P; Pierce, Eric; Diaz-Gil, Daniel

    2016-01-01

    . Measurements included bispectral index, genioglossus electromyography, ventilation, hypopharyngeal pressure, upper airway closing pressure, and change in end-expiratory lung volume during mask pressure drops. RESULTS: A total of 393 attempted breaths during occlusion maneuvers were analyzed. Upper airway......BACKGROUND: Volatile anesthetics and propofol impair upper airway stability and possibly respiratory upper airway dilator muscle activity. The magnitudes of these effects have not been compared at equivalent anesthetic doses. We hypothesized that upper airway closing pressure is less negative...... closing pressure was significantly less negative at deep versus shallow anesthesia (-10.8 ± 4.5 vs. -11.3 ± 4.4 cm H2O, respectively [mean ± SD]) and correlated with the bispectral index (P airway at deep anesthesia. Respiratory genioglossus activity during airway...

  10. Proportional positive airway pressure: a new concept to treat obstructive sleep apnoea.

    Science.gov (United States)

    Juhász, J; Becker, H; Cassel, W; Rostig, S; Peter, J H

    2001-03-01

    Proportional positive airway pressure (PPAP) was designed to optimize airway pressure for the therapy of obstructive sleep apnoea (OSA). In a randomized crossover prospective study, the clinical feasibility of PPAP and its immediate effects on the breathing disorder and sleep in comparison with continuous positive airway pressure (CPAP) was evaluated. Twelve patients requiring CPAP therapy underwent CPAP and PPAP titration in a random order. Obstructive and mixed respiratory events could be completely abolished with both forms of treatment. This efficacy could be achieved at a significantly lower mean mask pressure during PPAP titration (8.45+/-2.42 cmH2O) compared to CPAP (9.96+/-2.7 cmH2O) (p=0.002). The mean minimal arterial oxygen saturation (Sa,O2) (82.8+/-6.5%) on the diagnostic night increased significantly (pPPAP titration. Total sleep time, slow wave sleep and rapid eye movement (REM) sleep increased significantly by the same amount during both CPAP and PPAP titration (pPPAP titration night, four patients did not have a preference, and two patients preferred CPAP. The present data show that proportional positive airway pressure is as effective as continuous positive airway pressure in eliminating obstructive events and has the same immediate effect on sleep. The lower average mask pressure during proportional positive airway pressure implies potential advantages compared to continuous positive airway pressure. Proportional positive airway pressure presents a new effective therapeutic approach to obstructive sleep apnoea.

  11. Effect of Filters on the Noise Generated by Continuous Positive Airway Pressure Delivered via a Helmet

    Directory of Open Access Journals (Sweden)

    Ricardo Hernández-Molina

    2017-01-01

    Full Text Available Introduction: One of the problems that the delivery of continuous positive airway pressure (CPAP via a helmet poses is the generation of noise. The objective of our study was to assess the effect that the use of filter has on sound pressure levels generated by the delivery of positive airway pressure at different gas flow rates. Materials and Methods: Sound pressure levels generated by neonatal helmet CPAP delivery were measured at different gas flows (20, 30, and 40 l/min with and without a breathing filter. Noise intensity was measured by installing microphones in the inner ear of dummy heads wearing helmets. Results: The sound pressure level increased by 38% at a gas flow of 40 l/min, as compared to a gas flow of 20 l/min {74 dBA [interquartile range (IQR 2,2] vs 52 dBA (IQR 5,9, respectively}. Using the breathing filter as a diffuser has a variety of effects on sound pressure levels according to the gas flow rate. Conclusion: The intensity of the noise generated by helmet delivery of positive airway pressure depends on the type of helmet used, gas flow, and use or not of a diffuser filter. Breathing filters with gas flows over 30 l/min might not be recommended since they would not attenuate but will rather amplify sound pressure.

  12. Aerosol delivery and humidification with the Boussignac continuous positive airway pressure device.

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    Thille, Arnaud W; Bertholon, Jean-François; Becquemin, Marie-Hélène; Roy, Monique; Lyazidi, Aissam; Lellouche, François; Pertusini, Esther; Boussignac, Georges; Maître, Bernard; Brochard, Laurent

    2011-10-01

    A simple method for effective bronchodilator aerosol delivery while administering continuing continuous positive airway pressure (CPAP) would be useful in patients with severe bronchial obstruction. To assess the effectiveness of bronchodilator aerosol delivery during CPAP generated by the Boussignac CPAP system and its optimal humidification system. First we assessed the relationship between flow and pressure generated in the mask with the Boussignac CPAP system. Next we measured the inspired-gas humidity during CPAP, with several humidification strategies, in 9 healthy volunteers. We then measured the bronchodilator aerosol particle size during CPAP, with and without heat-and-moisture exchanger, in a bench study. Finally, in 7 patients with acute respiratory failure and airway obstruction, we measured work of breathing and gas exchange after a β(2)-agonist bronchodilator aerosol (terbutaline) delivered during CPAP or via standard nebulization. Optimal humidity was obtained only with the heat-and-moisture exchanger or heated humidifier. The heat-and-moisture exchanger had no influence on bronchodilator aerosol particle size. Work of breathing decreased similarly after bronchodilator via either standard nebulization or CPAP, but P(aO(2)) increased significantly only after CPAP aerosol delivery. CPAP bronchodilator delivery decreases the work of breathing as effectively as does standard nebulization, but produces a greater oxygenation improvement in patients with airway obstruction. To optimize airway humidification, a heat-and-moisture exchanger could be used with the Boussignac CPAP system, without modifying aerosol delivery.

  13. Coaxial Tubing Systems Increase Artificial Airway Resistance and Work of Breathing.

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    Wenzel, Christin; Schumann, Stefan; Spaeth, Johannes

    2017-09-01

    Tubing systems are an essential component of the ventilation circuit, connecting the ventilator to the patient's airways. Coaxial tubing systems incorporate the inspiratory tube within the lumen of the expiratory one. We hypothesized that by design, these tubing systems increase resistance to air flow compared with conventional ones. We investigated the flow-dependent pressure gradient across coaxial, conventional disposable, and conventional reusable tubing systems from 3 different manufacturers. Additionally, the additional work of breathing and perception of resistance during breathing through the different devices were determined in 18 healthy volunteers. The pressure gradient across coaxial tubing systems was up to 6 times higher compared with conventional ones (1.90 ± 0.03 cm H 2 O vs 0.34 ± 0.01 cm H 2 O, P tubing systems, accordingly. Our findings suggest that the use of coaxial tubing systems should be carefully considered with respect to their increased resistance. Copyright © 2017 by Daedalus Enterprises.

  14. Continuous Positive Airway Pressure Strategies with Bubble Nasal Continuous Positive Airway Pressure: Not All Bubbling Is the Same: The Seattle Positive Airway Pressure System.

    Science.gov (United States)

    Welty, Stephen E

    2016-12-01

    Premature neonates are predisposed to complications, including bronchopulmonary dysplasia (BPD). BPD is associated with long-term pulmonary and neurodevelopmental consequences. Noninvasive respiratory support with nasal continuous positive airway pressure (CPAP) has been recommended strongly by the American Academy of Pediatrics. However, CPAP implementation has shown at least a 50% failure rate. Enhancing nasal CPAP effectiveness may decrease the need for mechanical ventilation and reduce the incidence of BPD. Bubble nasal CPAP is better than nasal CPAP using mechanical devices and the bubbling provides air exchange in distal respiratory units. The Seattle PAP system reduces parameters that assess work of breathing. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Effects of condensate in the exhalation limb of neonatal circuits on airway pressure during bubble CPAP.

    Science.gov (United States)

    Youngquist, Tiffany M; Richardson, C Peter; Diblasi, Robert M

    2013-11-01

    Bubble CPAP is frequently used in spontaneously breathing infants with lung disease. Often bubble CPAP systems lack pressure alarms and pressure-release valves. We observed a large volume of condensate in the exhalation limb of a patient circuit and conducted a series of experiments to test the hypothesis that accumulated condensate could affect delivered pressures. An anatomically accurate nasal airway model of a preterm infant was attached to a spontaneously breathing lung model. A bubble CPAP system was attached to the nasal airway with bi-nasal short prongs, and the rate of fluid condensation was measured. Next, tracheal pressures were monitored digitally to detect changes in airway pressure related to condensate accumulation. Measurements were obtained with volumes of 0, 5, 10, 15, and 20 mL of water in the exhalation limb, at flows of 4, 6, 8, and 10 L/min. Measurements with 20 mL in the exhalation limb were recorded with and without a pressure-relief valve in the circuit. The rate of condensate accumulation was 3.8 mL/h. At volumes of ≥ 10 mL, noticeable alterations in the airway pressure waveforms and significant increases in mean tracheal pressure were observed. The pressure-relief valve effectively attenuated peak tracheal pressure, but only decreased mean pressure by 0.5-1.5 cm H2O. Condensate in the exhalation limb of the patient circuit during bubble CPAP can significantly increase pressure delivered to the patient. The back and forth movement of this fluid causes oscillations in airway pressure that are much greater than the oscillations created by gas bubbling out the exhalation tube into the water bath. We recommend continuously monitoring pressure at the nasal airway interface, placing an adjustable pressure-relief valve in the circuit, set to 5 cm H2O above the desired mean pressure, and emptying fluid from the exhalation limb every 2-3 hours.

  16. Higher levels of spontaneous breathing reduce lung injury in experimental moderate acute respiratory distress syndrome.

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    Carvalho, Nadja C; Güldner, Andreas; Beda, Alessandro; Rentzsch, Ines; Uhlig, Christopher; Dittrich, Susanne; Spieth, Peter M; Wiedemann, Bärbel; Kasper, Michael; Koch, Thea; Richter, Torsten; Rocco, Patricia R; Pelosi, Paolo; de Abreu, Marcelo Gama

    2014-11-01

    To assess the effects of different levels of spontaneous breathing during biphasic positive airway pressure/airway pressure release ventilation on lung function and injury in an experimental model of moderate acute respiratory distress syndrome. Multiple-arm randomized experimental study. University hospital research facility. Thirty-six juvenile pigs. Pigs were anesthetized, intubated, and mechanically ventilated. Moderate acute respiratory distress syndrome was induced by repetitive saline lung lavage. Biphasic positive airway pressure/airway pressure release ventilation was conducted using the airway pressure release ventilation mode with an inspiratory/expiratory ratio of 1:1. Animals were randomly assigned to one of four levels of spontaneous breath in total minute ventilation (n = 9 per group, 6 hr each): 1) biphasic positive airway pressure/airway pressure release ventilation, 0%; 2) biphasic positive airway pressure/airway pressure release ventilation, > 0-30%; 3) biphasic positive airway pressure/airway pressure release ventilation, > 30-60%, and 4) biphasic positive airway pressure/airway pressure release ventilation, > 60%. The inspiratory effort measured by the esophageal pressure time product increased proportionally to the amount of spontaneous breath and was accompanied by improvements in oxygenation and respiratory system elastance. Compared with biphasic positive airway pressure/airway pressure release ventilation of 0%, biphasic positive airway pressure/airway pressure release ventilation more than 60% resulted in lowest venous admixture, as well as peak and mean airway and transpulmonary pressures, redistributed ventilation to dependent lung regions, reduced the cumulative diffuse alveolar damage score across lungs (median [interquartile range], 11 [3-40] vs 18 [2-69]; p ventilation more than 0-30% and more than 30-60% showed a less consistent pattern of improvement in lung function, inflammation, and damage compared with biphasic positive airway

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

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    Marcelo de Mello Rieder

    2009-05-01

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

  18. Within-breath respiratory impedance and airway obstruction in patients with chronic obstructive pulmonary disease.

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    Silva, Karla Kristine Dames da; Faria, Alvaro Camilo Dias; Lopes, Agnaldo José; Melo, Pedro Lopes de

    2015-07-01

    Recent work has suggested that within-breath respiratory impedance measurements performed using the forced oscillation technique may help to noninvasively evaluate respiratory mechanics. We investigated the influence of airway obstruction on the within-breath forced oscillation technique in smokers and chronic obstructive pulmonary disease patients and evaluated the contribution of this analysis to the diagnosis of chronic obstructive pulmonary disease. Twenty healthy individuals and 20 smokers were assessed. The study also included 74 patients with stable chronic obstructive pulmonary disease. We evaluated the mean respiratory impedance (Zm) as well as values for the inspiration (Zi) and expiration cycles (Ze) at the beginning of inspiration (Zbi) and expiration (Zbe), respectively. The peak-to-peak impedance (Zpp=Zbe-Zbi) and the respiratory cycle dependence (ΔZrs=Ze-Zi) were also analyzed. The diagnostic utility was evaluated by investigating the sensitivity, the specificity and the area under the receiver operating characteristic curve. ClinicalTrials.gov: NCT01888705. Airway obstruction increased the within-breath respiratory impedance parameters that were significantly correlated with the spirometric indices of airway obstruction (R=-0.65, pdisease patients presented significant expiratory-inspiratory differences (p90%). We conclude the following: (1) chronic obstructive pulmonary disease introduces higher respiratory cycle dependence, (2) this increase is proportional to airway obstruction, and (3) the within-breath forced oscillation technique may provide novel parameters that facilitate the diagnosis of respiratory abnormalities in chronic obstructive pulmonary disease.

  19. Within-breath respiratory impedance and airway obstruction in patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Karla Kristine Dames da Silva

    2015-07-01

    Full Text Available OBJECTIVE: Recent work has suggested that within-breath respiratory impedance measurements performed using the forced oscillation technique may help to noninvasively evaluate respiratory mechanics. We investigated the influence of airway obstruction on the within-breath forced oscillation technique in smokers and chronic obstructive pulmonary disease patients and evaluated the contribution of this analysis to the diagnosis of chronic obstructive pulmonary disease. METHODS: Twenty healthy individuals and 20 smokers were assessed. The study also included 74 patients with stable chronic obstructive pulmonary disease. We evaluated the mean respiratory impedance (Zm as well as values for the inspiration (Zi and expiration cycles (Ze at the beginning of inspiration (Zbi and expiration (Zbe, respectively. The peak-to-peak impedance (Zpp=Zbe-Zbi and the respiratory cycle dependence (ΔZrs=Ze-Zi were also analyzed. The diagnostic utility was evaluated by investigating the sensitivity, the specificity and the area under the receiver operating characteristic curve. ClinicalTrials.gov: NCT01888705. RESULTS: Airway obstruction increased the within-breath respiratory impedance parameters that were significantly correlated with the spirometric indices of airway obstruction (R=−0.65, p90%. CONCLUSIONS: We conclude the following: (1 chronic obstructive pulmonary disease introduces higher respiratory cycle dependence, (2 this increase is proportional to airway obstruction, and (3 the within-breath forced oscillation technique may provide novel parameters that facilitate the diagnosis of respiratory abnormalities in chronic obstructive pulmonary disease.

  20. Sibutramine versus continuous positive airway pressure in obese obstructive sleep apnoea patients.

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    Ferland, A; Poirier, P; Sériès, F

    2009-09-01

    The aim of the present study was to compare the efficacy of 1 yr of sibutramine-induced weight loss versus continuous positive airway pressure (CPAP) treatment on sleep-disordered breathing, cardiac autonomic function and systemic blood pressure in obese patients with obstructive sleep apnoea. Subjects with a body mass index of > or =30 kg.m(-2) without previous treatment for obstructive sleep apnoea underwent either sibutramine (n = 22) or CPAP (n = 18) treatment for 1 yr. Sibutramine induced a 5.4+/-1.4 kg decrease in body weight compared to the CPAP group, in which no changes in anthropometric variables were observed. The CPAP treatment improved all sleep and respiratory variables, whereas sibutramine-induced weight loss improved only nocturnal arterial oxygen saturation profile. Only CPAP treatment improved night-time systolic and diastolic blood pressure and 24-h and daytime ambulatory diastolic blood pressure. Sibutramine-induced weight loss had no impact on indices of heart rate variability, whereas CPAP treatment increased daytime time domain indices. CPAP treatment for 1 yr had beneficial impacts on nocturnal breathing disturbances, and improved nocturnal oxygenation, night-time systolic and diastolic blood pressure, and daytime cardiac parasympathetic modulation. Sibutramine did not improve sleep-disordered breathing, systemic blood pressure or heart rate variability. There were no adverse effects, such as increment in blood pressure or arrhythmias, associated with this treatment regimen.

  1. Continuous Positive Airway Pressure (CPAP)

    Science.gov (United States)

    ... ENT Doctor Near You Continuous Positive Airway Pressure (CPAP) Continuous Positive Airway Pressure (CPAP) Patient Health Information ... relations staff at newsroom@entnet.org . What Is CPAP? The most common and effective nonsurgical treatment for ...

  2. Risk assessment of sleeping disorder breathing based on upper airway centerline evaluation

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    Alsufyani, Noura; Shen, Rui; Cheng, Irene; Major, Paul

    2013-02-01

    One of the most important breathing disorders in childhood is obstructive sleep apnea syndrome which affects 2-3% of children, and the reported failure rate of surgical treatment was as high as 54%. A possible reason in respiratory complications is having reduced dimensions of the upper airway which are further compressed when muscle tone is decreased during sleep. In this study, we use Cone-beam computed tomography (CBCT) to assess the location or cause of the airway obstruction. To date, all studies analyzing the upper airway in subjects with Sleeping Disorder Breathing were based on linear, area, or volumetric measurements, which are global computations and can easily ignore local significance. Skeletonization was initially introduced as a 3D modeling technique by which representative medial points of a model are extracted to generate centerlines for evaluations. Although centerlines have been commonly used in guiding surgical procedures, our novelty lies in comparing its geometric properties before and after surgeries. We apply 3D data refinement, registration and projection steps to quantify and localize the geometric deviation in target airway regions. Through cross validation with corresponding subjects' therapy data, we expect to quantify the tolerance threshold beyond which reduced dimensions of the upper airway are not clinically significant. The ultimate goal is to utilize this threshold to identify patients at risk of complications. Outcome from this research will also help establish a predictive model for training and to estimate treatment success based on airway measurements prior to intervention. Preliminary results demonstrate the feasibility of our approach.

  3. Increased airway reactivity in a neonatal mouse model of Continuous Positive Airway Pressure (CPAP)

    Science.gov (United States)

    Mayer, Catherine A.; Martin, Richard J.; MacFarlane, Peter M.

    2015-01-01

    Background Continuous positive airway pressure (CPAP) is a primary form of respiratory support used in the intensive care of preterm infants, but its long-term effects on airway (AW) function are unknown. Methods We developed a neonatal mouse model of CPAP treatment to determine whether it modifies later AW reactivity. Un-anesthetized spontaneously breathing mice were fitted with a mask to deliver CPAP (6cmH2O, 3hrs/day) for 7 consecutive days starting at postnatal day 1. Airway reactivity to methacholine was assessed using the in vitro living lung slice preparation. Results One week of CPAP increased AW responsiveness to methacholine in male, but not female mice, compared to untreated control animals. The AW hyper-reactivity of male mice persisted for 2 weeks (at P21) after CPAP treatment ended. 4 days of CPAP, however, did not significantly increase AW reactivity. Females also exhibited AW hyper-reactivity at P21, suggesting a delayed response to early (7 days) CPAP treatment. The effects of 7 days of CPAP on hyper-reactivity to methacholine were unique to smaller AWs whereas larger ones were relatively unaffected. Conclusion These data may be important to our understanding of the potential long-term consequences of neonatal CPAP therapy used in the intensive care of preterm infants. PMID:25950451

  4. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Active Cycle of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy ... clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency Chest Wall ...

  5. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Cycle of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy Coughing ... Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency Chest Wall Oscillation ( ...

  6. The relationship between partial upper-airway obstruction and inter-breath transition period during sleep.

    Science.gov (United States)

    Mann, Dwayne L; Edwards, Bradley A; Joosten, Simon A; Hamilton, Garun S; Landry, Shane; Sands, Scott A; Wilson, Stephen J; Terrill, Philip I

    2017-10-01

    Short pauses or "transition-periods" at the end of expiration and prior to subsequent inspiration are commonly observed during sleep in humans. However, the role of transition periods in regulating ventilation during physiological challenges such as partial airway obstruction (PAO) has not been investigated. Twenty-nine obstructive sleep apnea patients and eight controls underwent overnight polysomnography with an epiglottic catheter. Sustained-PAO segments (increased epiglottic pressure over ≥5 breaths without increased peak inspiratory flow) and unobstructed reference segments were manually scored during apnea-free non-REM sleep. Nasal pressure data was computationally segmented into inspiratory (T I , shortest period achieving 95% inspiratory volume), expiratory (T E , shortest period achieving 95% expiratory volume), and inter-breath transition period (T Trans , period between T E and subsequent T I ). Compared with reference segments, sustained-PAO segments had a mean relative reduction in T Trans (-24.7±17.6%, P<0.001), elevated T I (11.8±10.5%, P<0.001), and a small reduction in T E (-3.9±8.0, P≤0.05). Compensatory increases in inspiratory period during PAO are primarily explained by reduced transition period and not by reduced expiratory period. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Chest physiotherapy with positive expiratory pressure breathing after abdominal and thoracic surgery: a systematic review.

    Science.gov (United States)

    Orman, J; Westerdahl, E

    2010-03-01

    A variety of chest physiotherapy techniques are used following abdominal and thoracic surgery to prevent or reduce post-operative complications. Breathing techniques with a positive expiratory pressure (PEP) are used to increase airway pressure and improve pulmonary function. No systematic review of the effects of PEP in surgery patients has been performed previously. The purpose of this systematic review was to determine the effect of PEP breathing after an open upper abdominal or thoracic surgery. A literature search of randomised-controlled trials (RCT) was performed in five databases. The trials included were systematically reviewed by two independent observers and critically assessed for methodological quality. We selected six RCT evaluating the PEP technique performed with a mechanical device in spontaneously breathing adult patients after abdominal or thoracic surgery via thoracotomy. The methodological quality score varied between 4 and 6 on the Physiotherapy Evidence Database score. The studies were published between 1979 and 1993. Only one of the included trials showed any positive effects of PEP compared to other breathing techniques. Today, there is scarce scientific evidence that PEP treatment is better than other physiotherapy breathing techniques in patients undergoing abdominal or thoracic surgery. There is a lack of studies investigating the effect of PEP over placebo or no physiotherapy treatment.

  8. Efficacy of the addition of positive airway pressure to conventional chest physiotherapy in resolution of pleural effusion after drainage: protocol for a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Elinaldo da Conceição dos Santos

    2015-04-01

    Discussion: Conventional chest physiotherapy and intermittent positive airway pressure breathing are widely indicated for people with pleural effusion and chest drains; however, no studies have evaluated the real benefit of this type of treatment. Our hypothesis is that optimised lung expansion achieved through the application of intermittent positive airway pressure will accelerate the reabsorption of pleural effusion, decrease the duration of chest drainage and respiratory system impairment, reduce the length of hospital stay, and reduce the incidence of pulmonary complications.

  9. Use of Respiratory Support in the Biphase Ventilation Airway Mode in the Newborn

    OpenAIRE

    S. N. Koval; A. Ye. Kulagin

    2006-01-01

    Biphasic positive airway pressure (BIPAP) (also known as DuoPAP, BiLevel, BiVent, PCV+, SPAP) is a mode of ventilation with cycling variations between two continuous positive airway pressure levels. It is a mixture of pressure controlled ventilation and spontaneous breathing, which is unrestricted in each phase of the respiratory cycle. The volume displacement caused by the difference between Phigh and Plow airway pressure level. The phase time ratio (PTR — the BIPAP frequency) is calculated ...

  10. A Comparative Study of Cuffed Pharyngeal Tube (CPR with Endotracheal Tube in Airway Management and Ventilation of Spontaneously Breathing Patients Undergoing General Anesthesia

    Directory of Open Access Journals (Sweden)

    F Mir Mohammad Sadeghi

    2002-09-01

    Full Text Available Background: Cuffed pharyngeal tube is a device designed for ventilation of anesthetized patients. CPT has advantages over face mask including: maintaining of face mask can be difficult and boring after several minutes and mobility of the practitioner is reduced due to involvement of hands. Mask pressure can cause soft tissue and nerve damage around the nose. Anesthetic gas leakage from the mask adds to the operation room pollution. In difficult intubation CPT can be life-saving. Materials and Methods: In our study CPT was compared with endotracheal tube (ET in anesthetized patients. A scoring system for evaluating ventilation of patients was designed using symmetric chest wall motion during ventilation with anesthesia bag and sensing lung compliance through it, auscultation of breathing sounds, oscilation of bag with breathing and peripheral oxygen saturation by pulse oxymetry. Respiratory complications (pulmonary aspiration, Iaryngospasm and bronchospasm, nausea and vomiting were looked for during anesthesia. Results: The results showed that CPT was successful as ET in ventilation of spontaneously breathing patients and incidence of respiratory complications with CPT was no more than ET. Airway resistance was significantly greater with CPT than ET (P<0.05. Patients with ET had significantly greater incidence of sore throat than with CPT (P<0.05. Conclusion: Thus we concluded that CPT can be used for ventilation of anesthetized patients not predisposed to pulmonary aspiration and whose peak airway pressure does not exceed 20-25 CmH2O.

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

    Directory of Open Access Journals (Sweden)

    Samantha Torres Grams

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

  12. Continuous positive airway pressure breathing increases cranial spread of sensory blockade after cervicothoracic epidural injection of lidocaine.

    NARCIS (Netherlands)

    Visser, W.A.; Eerd, M.J. van; Seventer, R. van; Gielen, M.J.M.; Giele, J.L.P.; Scheffer, G.J.

    2007-01-01

    BACKGROUND: Continuous positive airway pressure (CPAP) increases the caudad spread of sensory blockade after low-thoracic epidural injection of lidocaine. We hypothesized that CPAP would increase cephalad spread of blockade after cervicothoracic epidural injection. METHODS: Twenty patients with an

  13. Breath-Hold Diving.

    Science.gov (United States)

    Fitz-Clarke, John R

    2018-03-25

    Breath-hold diving is practiced by recreational divers, seafood divers, military divers, and competitive athletes. It involves highly integrated physiology and extreme responses. This article reviews human breath-hold diving physiology beginning with an historical overview followed by a summary of foundational research and a survey of some contemporary issues. Immersion and cardiovascular adjustments promote a blood shift into the heart and chest vasculature. Autonomic responses include diving bradycardia, peripheral vasoconstriction, and splenic contraction, which help conserve oxygen. Competitive divers use a technique of lung hyperinflation that raises initial volume and airway pressure to facilitate longer apnea times and greater depths. Gas compression at depth leads to sequential alveolar collapse. Airway pressure decreases with depth and becomes negative relative to ambient due to limited chest compliance at low lung volumes, raising the risk of pulmonary injury called "squeeze," characterized by postdive coughing, wheezing, and hemoptysis. Hypoxia and hypercapnia influence the terminal breakpoint beyond which voluntary apnea cannot be sustained. Ascent blackout due to hypoxia is a danger during long breath-holds, and has become common amongst high-level competitors who can suppress their urge to breathe. Decompression sickness due to nitrogen accumulation causing bubble formation can occur after multiple repetitive dives, or after single deep dives during depth record attempts. Humans experience responses similar to those seen in diving mammals, but to a lesser degree. The deepest sled-assisted breath-hold dive was to 214 m. Factors that might determine ultimate human depth capabilities are discussed. © 2018 American Physiological Society. Compr Physiol 8:585-630, 2018. Copyright © 2018 American Physiological Society. All rights reserved.

  14. Influence of upper body position on middle cerebral artery blood velocity during continuous positive airway pressure breathing

    DEFF Research Database (Denmark)

    Højlund Rasmussen, J; Mantoni, T; Belhage, B

    2007-01-01

    Continuous positive airway pressure (CPAP) is a treatment modality for pulmonary oxygenation difficulties. CPAP impairs venous return to the heart and, in turn, affects cerebral blood flow (CBF) and augments cerebral blood volume (CBV). We considered that during CPAP, elevation of the upper body ...

  15. Leukotriene-B4 concentrations in exhaled breath condensate and lung function after thirty minutes of breathing technically dried compressed air.

    Science.gov (United States)

    Neubauer, Birger; Struck, Niclas; Mutzbauer, Till S; Schotte, Ulrich; Langfeldt, Norbert; Tetzlaff, Kay

    2002-01-01

    In previous studies it had been shown that leukotriene-B4 [LTB4] concentrations in the exhaled breath mirror the inflammatory activity of the airways if the respiratory tract has been exposed to occupational hazards. In diving the respiratory tract is exposed to cold and dry air and the nasopharynx, as the site of breathing-gas warming and humidification, is bypassed. The aim of the present study was to obtain LTB4-concentrations in the exhaled breath and spirometric data of 17 healthy subjects before and after thirty minutes of technically dried air breathing at normobar ambient pressure. The exhaled breath was collected non-invasively, via a permanently cooled expiration tube. The condensate was measured by a standard enzyme immunoassay for LTB4. Lung function values (FVC, FEV1, MEF 25, MEF 50) were simultaneously obtained by spirometry. The measured pre- and post-exposure LTB4- concentrations as well as the lung function values were in the normal range. The present data gave no evidence for any inflammatory activity in the subjects' airways after thirty minutes breathing technically dried air.

  16. Noninvasive Positive Pressure Ventilation or Conventional Mechanical Ventilation for Neonatal Continuous Positive Airway Pressure Failure

    Directory of Open Access Journals (Sweden)

    Zohreh Badiee

    2014-01-01

    Full Text Available Background: The aim of this study was to assess the success rate of nasal intermittent positive pressure ventilation (NIPPV for treatment of continuous positive airway pressure (CPAP failure and prevention of conventional ventilation (CV in preterm neonates. Methods: Since November 2012 to April 2013, a total number of 55 consecutive newborns with gestational ages of 26-35 weeks who had CPAP failure were randomly assigned to one of the two groups. The NIPPV group received NIPPV with the initial peak inspiratory pressure (PIP of 16-20 cmH 2 O and frequency of 40-60 breaths/min. The CV group received PIP of 12-20 cmH 2 O and frequency of 40-60 breaths/min. Results: About 74% of newborns who received NIPPV for management of CPAP failure responded to NIPPV and did not need intubation and mechanical ventilation. Newborns with lower postnatal age at entry to the study and lower 5 min Apgar score more likely had NIPPV failure. In addition, treatment failure was higher in newborns who needed more frequent doses of surfactant. Duration of oxygen therapy was 9.28 days in CV group and 7.77 days in NIPPV group (P = 0.050. Length of hospital stay in CV group and NIPPV groups were 48.7 and 41.7 days, respectively (P = 0.097. Conclusions: NIPPV could decrease the need for intubation and mechanical ventilation in preterm infants with CPAP failure.

  17. The New Perilaryngeal Airway (CobraPLA™)1 Is as Efficient as the Laryngeal Mask Airway (LMA™)2, But Provides Better Airway Sealing Pressures

    Science.gov (United States)

    Akça, Ozan; Wadhwa, Anupama; Sengupta, Papiya; Durrani, Jaleel; Hanni, Keith; Wenke, Mary; Yücel, Yüksel; Lenhardt, Rainer; Doufas, Anthony G.; Sessler, Daniel I.

    2006-01-01

    The Laryngeal Mask Airway (LMA) is a frequently-used efficient airway device, yet it sometimes seals poorly, thus reducing the efficacy of positive-pressure ventilation. The Perilaryngeal Airway (CobraPLA) is a novel airway device with a larger pharyngeal cuff (when inflated). We tested the hypothesis that the CobraPLA was superior to LMA with regard to insertion time and airway sealing pressure and comparable to LMA in airway adequacy and recovery characteristics. After midazolam and fentanyl, 81 ASA I-II outpatients having elective surgery were randomized to receive an LMA or CobraPLA. Anesthesia was induced with propofol (2.5 mg/kg, IV), and the airway inserted. We measured 1) insertion time; 2) adequacy of the airway (no leak at 15-cm-H2O peak pressure or tidal volume of 5 ml/kg); 3) airway sealing pressure; 4) number of repositioning attempts; and 5) sealing quality (no leak at tidal volume of 8 ml/kg). At the end of surgery, gastric insufflation, postoperative sore throat, dysphonia, and dysphagia were evaluated. Data were compared with unpaired t-tests, chi-square tests, or Fisher’s Exact tests; P<0.05 was significant. Patient characteristics, insertion times, airway adequacy, number of repositioning attempts, and recovery were similar in each group. Airway sealing pressure was significantly greater with CobraPLA (23±6 cm H2O) than LMA (18±5 cm H2O, P<0.001). The CobraPLA has insertion characteristics similar to LMA, but better airway sealing capabilities. PMID:15281543

  18. Impact of microarousal associated with increased negative esophageal pressure in sleep-disordered breathing.

    Science.gov (United States)

    Sukegawa, Mayo; Noda, Akiko; Yasuda, Yoshinari; Nakata, Seiichi; Sugiura, Tatsuki; Miyata, Seiko; Honda, Kumiko; Hasegawa, Yoshinori; Nakashima, Tsutomu; Koike, Yasuo

    2009-11-01

    "Microarousals" during sleep have not been analyzed systematically. We investigated the importance of "microarousals" (lasting 1.5-3 s). Standard polysomnography including esophageal pressure (Pes) assessment was performed on ten patients (aged 54.0 +/- 5.0 years) with respiratory effort-related arousal > or =5/h. We measured the number of arousals per hour (American Sleep Disorders Association (ASDA) arousal index) and the number of microarousals lasting 1.5-3 s per hour (mASDA arousal index). On the night after the baseline sleep study, we performed overnight continuous positive airway pressure (CPAP) titration. mASDA arousals, characterized by lower Pes values, were observed more frequently in patients with sleep-disordered breathing. The Pes results did not differ significantly between ASDA and mASDA arousals (-15.6 +/- -5.0 vs -15.0 +/- -4.4 cmH(2)O). mASDA arousals were significantly improved by CPAP treatment (mASDA arousals, 82.6 +/- 60.1 vs 6.0 +/- 1.4/h). mASDA arousals were characterized by an increase in Pes. mASDA arousals are thus key to our understanding of clinical manifestations in patients with sleep-disordered breathing.

  19. The 30-year evolution of airway pressure release ventilation (APRV).

    Science.gov (United States)

    Jain, Sumeet V; Kollisch-Singule, Michaela; Sadowitz, Benjamin; Dombert, Luke; Satalin, Josh; Andrews, Penny; Gatto, Louis A; Nieman, Gary F; Habashi, Nader M

    2016-12-01

    Airway pressure release ventilation (APRV) was first described in 1987 and defined as continuous positive airway pressure (CPAP) with a brief release while allowing the patient to spontaneously breathe throughout the respiratory cycle. The current understanding of the optimal strategy to minimize ventilator-induced lung injury is to "open the lung and keep it open". APRV should be ideal for this strategy with the prolonged CPAP duration recruiting the lung and the minimal release duration preventing lung collapse. However, APRV is inconsistently defined with significant variation in the settings used in experimental studies and in clinical practice. The goal of this review was to analyze the published literature and determine APRV efficacy as a lung-protective strategy. We reviewed all original articles in which the authors stated that APRV was used. The primary analysis was to correlate APRV settings with physiologic and clinical outcomes. Results showed that there was tremendous variation in settings that were all defined as APRV, particularly CPAP and release phase duration and the parameters used to guide these settings. Thus, it was impossible to assess efficacy of a single strategy since almost none of the APRV settings were identical. Therefore, we divided all APRV studies divided into two basic categories: (1) fixed-setting APRV (F-APRV) in which the release phase is set and left constant; and (2) personalized-APRV (P-APRV) in which the release phase is set based on changes in lung mechanics using the slope of the expiratory flow curve. Results showed that in no study was there a statistically significant worse outcome with APRV, regardless of the settings (F-ARPV or P-APRV). Multiple studies demonstrated that P-APRV stabilizes alveoli and reduces the incidence of acute respiratory distress syndrome (ARDS) in clinically relevant animal models and in trauma patients. In conclusion, over the 30 years since the mode's inception there have been no strict

  20. A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

    Science.gov (United States)

    Yin, Youbing; Choi, Jiwoong; Hoffman, Eric A.; Tawhai, Merryn H.; Lin, Ching-Long

    2012-01-01

    A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C1 continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung. PMID:23794749

  1. A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Youbing, E-mail: youbing-yin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Choi, Jiwoong, E-mail: jiwoong-choi@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Hoffman, Eric A., E-mail: eric-hoffman@uiowa.edu [Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Department of Biomedical Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242 (United States); Tawhai, Merryn H., E-mail: m.tawhai@auckland.ac.nz [Auckland Bioengineering Institute, The University of Auckland, Auckland (New Zealand); Lin, Ching-Long, E-mail: ching-long-lin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States)

    2013-07-01

    A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C{sub 1} continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung.

  2. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Inspiratory airway pressure meter. 868.1780 Section 868.1780 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the amount...

  3. A passive quantitative measurement of airway resistance using depth data.

    Science.gov (United States)

    Ostadabbas, Sarah; Bulach, Christoph; Ku, David N; Anderson, Larry J; Ghovanloo, Maysam

    2014-01-01

    The Respiratory Syncytial Virus (RSV) is the most common cause of serious lower respiratory tract infections in infants and young children. RSV often causes increased airway resistance, clinically detected as wheezing by chest auscultation. In this disease, expiratory flows are significantly reduced due to the high resistance in patient's airway passages. A quantitative method for measuring resistance can have a great benefit to diagnosis and management of children with RSV infections as well as with other lung diseases. Airway resistance is defined as the lung pressure divided by the airflow. In this paper, we propose a method to quantify resistance through a simple, non-contact measurement of chest volume that can act as a surrogate measure of the lung pressure and volumetric airflow. We used depth data collected by a Microsoft Kinect camera for the measurement of the lung volume over time. In our experimentation, breathing through a number of plastic straws induced different airway resistances. For a standard spirometry test, our volume/flow estimation using Kinect showed strong correlation with the flow data collected by a commercially-available spirometer (five subjects, each performing 20 breathing trials, correlation coefficient = 0.88, with 95% confidence interval). As the number of straws decreased, emulating a higher airway obstruction, our algorithm was sufficient to distinguish between several levels of airway resistance.

  4. Effect of airway acidosis and alkalosis on airway vascular smooth muscle responsiveness to albuterol.

    Science.gov (United States)

    Cancado, Jose E; Mendes, Eliana S; Arana, Johana; Horvath, Gabor; Monzon, Maria E; Salathe, Matthias; Wanner, Adam

    2015-04-02

    In vitro and animal experiments have shown that the transport and signaling of β2-adrenergic agonists are pH-sensitive. Inhaled albuterol, a hydrophilic β2-adrenergic agonist, is widely used for the treatment of obstructive airway diseases. Acute exacerbations of obstructive airway diseases can be associated with changes in ventilation leading to either respiratory acidosis or alkalosis thereby affecting albuterol responsiveness in the airway. The purpose of this study was to determine if airway pH has an effect on albuterol-induced vasodilation in the airway. Ten healthy volunteers performed the following respiratory maneuvers: quiet breathing, hypocapnic hyperventilation, hypercapnic hyperventilation, and eucapnic hyperventilation (to dissociate the effect of pH from the effect of ventilation). During these breathing maneuvers, exhaled breath condensate (EBC) pH and airway blood flow response to inhaled albuterol (ΔQ̇aw) were assessed. Mean ± SE EBC pH (units) and ΔQ̇aw (μl.min(-1).mL(-1)) were 6.4 ± 0.1 and 16.8 ± 1.9 during quiet breathing, 6.3 ± 0.1 and 14.5 ± 2.4 during eucapnic hyperventilation, 6.6 ± 0.2 and -0.2 ± 1.8 during hypocapnic hyperventilation (p = 0.02 and <0.01 vs. quiet breathing), and 5.9 ± 0.1 and 2.0 ± 1.5 during hypercapnic hyperventilation (p = 0.02 and <0.02 vs quiet breathing). Albuterol responsiveness in the airway as assessed by ΔQ̇aw is pH sensitive. The breathing maneuver associated with decreased and increased EBC pH both resulted in a decreased responsiveness independent of the level of ventilation. These findings suggest an attenuated response to hydrophilic β2-adrenergic agonists during airway disease exacerbations associated with changes in pH. Registered at clinicaltrials.gov: NCT01216748 .

  5. Canadian Thoracic Society 2011 Guideline Update: Diagnosis and Treatment of Sleep Disordered Breathing

    Directory of Open Access Journals (Sweden)

    John Fleetham

    2011-01-01

    Full Text Available The Canadian Thoracic Society (CTS published an executive summary of guidelines for the diagnosis and treatment of sleep disordered breathing in 2006/2007. These guidelines were developed during several meetings by a group of experts with evidence grading based on committee consensus. These guidelines were well received and the majority of the recommendations remain unchanged. The CTS embarked on a more rigorous process for the 2011 guideline update, and addressed eight areas that were believed to be controversial or in which new data emerged. The CTS Sleep Disordered Breathing Committee posed specific questions for each area. The recommendations regarding maximum assessment wait times, portable monitoring, treatment of asymptomatic adult obstructive sleep apnea patients, treatment with conventional continuous positive airway pressure compared with automatic continuous positive airway pressure, and treatment of central sleep apnea syndrome in heart failure patients replace the recommendations in the 2006/2007 guidelines. The recommendations on bariatric surgery, complex sleep apnea and optimum positive airway pressure technologies are new topics, which were not covered in the 2006/2007 guidelines.

  6. Short term evaluation of respiratory effort by premature infants supported with bubble nasal continuous airway pressure using Seattle-PAP and a standard bubble device

    Science.gov (United States)

    Welty, Stephen E.; Rusin, Craig G.; Stanberry, Larissa I.; Mandy, George T.; Gest, Alfred L.; Ford, Jeremy M.; Backes, Carl H.; Richardson, C. Peter; Howard, Christopher R.; Hansen, Thomas N.

    2018-01-01

    Background Almost one million prematurely born infants die annually from respiratory insufficiency, predominantly in countries with limited access to respiratory support for neonates. The primary hypothesis tested in the present study was that a modified device for bubble nasal continuous positive airway pressure (Bn-CPAP) would provide lower work of spontaneous breathing, estimated by esophageal pressure-rate products. Methods Infants born CPAP with FiO2 CPAP, then 2 h with Bn-CPAP using a modified bubble device presently termed Seattle-PAP, which produces a different pattern of pressure fluctuations and which provided greater respiratory support in preclinical studies, then 2 h on standard Bn-CPAP. Results All 40 infants enrolled completed the study and follow-up through 36 wks post menstrual age or hospital discharge, whichever came first. No infants were on supplemental oxygen at completion of follow-up. No infants developed pneumothoraces or nasal trauma, and no adverse events attributed to the study were observed. Pressure-rate products on the two devices were not different, but effort of breathing, assessed by areas under esophageal pressure-time curves, was lower with Seattle-PAP than with standard Bn-CPAP. Conclusion Use of Seattle-PAP to implement Bn-CPAP lowers the effort of breathing exerted even by relatively healthy spontaneously breathing premature neonates. Whether the lower effort of breathing observed with Seattle-PAP translates to improvements in neonatal mortality or morbidity will need to be determined by studies in appropriate patient populations. PMID:29590143

  7. Treatment response of airway clearance assessed by single-breath washout in children with cystic fibrosis.

    Science.gov (United States)

    Abbas, Chiara; Singer, Florian; Yammine, Sophie; Casaulta, Carmen; Latzin, Philipp

    2013-12-01

    We studied the ability of 4 single-breath gas washout (SBW) tests to measure immediate effects of airway clearance in children with CF. 25 children aged 4-16 years with CF performed pulmonary function tests to assess short-term variability at baseline and response to routine airway clearance. Tidal helium and sulfur hexafluoride (double-tracer gas: DTG) SBW, tidal capnography, tidal and vital capacity nitrogen (N2) SBW and spirometry were applied. We analyzed the gasses' phase III slope (SnIII--normalized for tidal volume) and FEV1 from spirometry. SnIII from tidal DTG-SBW, SnIII from vital capacity N2-SBW, and FEV1 improved significantly after airway clearance. From these tests, individual change of SnIII from tidal DTG-SBW and FEV1 exceeded short-term variability in 10 and 6 children. With the tidal DTG-SBW, an easy and promising test for peripheral gas mixing efficiency, immediate pulmonary function response to airway clearance can be assessed in CF children. Copyright © 2013 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  8. The importance of clinical monitoring for compliance with Continuous Positive Airway Pressure.

    Science.gov (United States)

    Pelosi, Lucas B; Silveira, Mariana L C; Eckeli, Alan L; Chayamiti, Emilia M P C; Almeida, Leila A; Sander, Heidi H; Küpper, Daniel S; Valera, Fabiana C P

    Obstructive sleep apnea syndrome is currently a public health problem of great importance. When misdiagnosed or improperly treated, it can lead to serious consequences on patients' quality of life. The gold standard treatment for cases of obstructive sleep apnea syndrome, especially in mild to severe and symptomatic cases, is continuous positive airway pressure therapy. Compliance with continuous positive airway pressure therapy is directly dependent on the active participation of the patient, which can be influenced by several factors. The objective of this study is to describe the factors related to compliance with continuous positive airway pressure therapy, and to analyze which associated factors directly influence the efficiency of the treatment. Patients who received continuous positive airway pressure therapy through the Municipal Health Department of the city of Ribeirão Preto were recruited. A structured questionnaire was administered to the patients. Compliance with continuous positive airway pressure therapy was assessed by average hours of continuous positive airway pressure therapy usage per night. Patients with good compliance (patients using continuous positive airway pressure therapy ≥4h/night) were compared to those with poor compliance (patients using <4h/night). 138 patients were analyzed: 77 (55.8%) were considered compliant while 61 (44.2%) were non-compliant. The comparison between the two groups showed that regular monitoring by a specialist considerably improved compliance with continuous positive airway pressure therapy (odds ratio, OR=2.62). Compliance with continuous positive airway pressure therapy is related to educational components, which can be enhanced with continuous and individualized care to patients with obstructive sleep apnea syndrome. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  9. Transpulmonary pressures and lung mechanics with glossopharyngeal insufflation and exsufflation beyond normal lung volumes in competitive breath-hold divers.

    Science.gov (United States)

    Loring, Stephen H; O'Donnell, Carl R; Butler, James P; Lindholm, Peter; Jacobson, Francine; Ferrigno, Massimo

    2007-03-01

    Throughout life, most mammals breathe between maximal and minimal lung volumes determined by respiratory mechanics and muscle strength. In contrast, competitive breath-hold divers exceed these limits when they employ glossopharyngeal insufflation (GI) before a dive to increase lung gas volume (providing additional oxygen and intrapulmonary gas to prevent dangerous chest compression at depths recently greater than 100 m) and glossopharyngeal exsufflation (GE) during descent to draw air from compressed lungs into the pharynx for middle ear pressure equalization. To explore the mechanical effects of these maneuvers on the respiratory system, we measured lung volumes by helium dilution with spirometry and computed tomography and estimated transpulmonary pressures using an esophageal balloon after GI and GE in four competitive breath-hold divers. Maximal lung volume was increased after GI by 0.13-2.84 liters, resulting in volumes 1.5-7.9 SD above predicted values. The amount of gas in the lungs after GI increased by 0.59-4.16 liters, largely due to elevated intrapulmonary pressures of 52-109 cmH(2)O. The transpulmonary pressures increased after GI to values ranging from 43 to 80 cmH(2)O, 1.6-2.9 times the expected values at total lung capacity. After GE, lung volumes were reduced by 0.09-0.44 liters, and the corresponding transpulmonary pressures decreased to -15 to -31 cmH(2)O, suggesting closure of intrapulmonary airways. We conclude that the lungs of some healthy individuals are able to withstand repeated inflation to transpulmonary pressures far greater than those to which they would normally be exposed.

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

    Science.gov (United States)

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

    2009-08-01

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

  11. Continuous positive airway pressure treatment increases bronchial reactivity in obstructive sleep apnea patients.

    Science.gov (United States)

    Korczynski, Piotr; Gorska, Katarzyna; Przybylowski, Tadeusz; Bielicki, Piotr; Zielinski, Jan; Chazan, Ryszarda

    2009-01-01

    The effects of continuous positive airway pressure (CPAP) treatment on the function of the lower airways are poorly understood. One of the methods used to determine the influence of positive pressure breathing on lower airways is the bronchial hyperreactivity test. Some authors report that CPAP increases bronchial hyperreactivity, while others report decreases. To assess the influence of CPAP treatment on bronchial reactivity and the effects of bronchial hyperreactivity on compliance to CPAP treatment. The study group consisted of 101 obstructive sleep apnea syndrome patients (88 men and 13 women) with a mean age of 51 ± 11 years, mean apnea-hypopnea index of 53 ± 20 and mean body mass index of 32.6 ± 5.4. Patients were randomly assigned to a treatment group that received 3 weeks of CPAP therapy (group 1) or to a nontreatment control group (group 2). Pulmonary function tests and the methacholine bronchial provocation test were performed at baseline and 3 weeks later. There were no statistically significant differences between treated and control groups in anthropometry and polysomnography variables. At baseline, bronchial hyperreactivity was found in 6 patients from group 1 and 5 patients from group 2. A significant increase in bronchial reactivity was observed after CPAP treatment. Log PC20M decreased from 1.38 ± 0.30 at baseline to 1.26 ± 0.50 (p bronchial hyperreactivity during CPAP treatment were characterized by significantly lower FEV1, FVC and MEF50 values. CPAP produces statistically significant bronchial hyperreactivity. However, there were no clinical symptoms and it is not necessary to withdraw previous therapies. Copyright © 2009 S. Karger AG, Basel.

  12. A mechanical design principle for tissue structure and function in the airway tree.

    Science.gov (United States)

    LaPrad, Adam S; Lutchen, Kenneth R; Suki, Béla

    2013-01-01

    With every breath, the dynamically changing mechanical pressures must work in unison with the cells and soft tissue structures of the lung to permit air to efficiently traverse the airway tree and undergo gas exchange in the alveoli. The influence of mechanics on cell and tissue function is becoming apparent, raising the question: how does the airway tree co-exist within its mechanical environment to maintain normal cell function throughout its branching structure of diminishing dimensions? We introduce a new mechanical design principle for the conducting airway tree in which mechanotransduction at the level of cells is driven to orchestrate airway wall structural changes that can best maintain a preferred mechanical microenvironment. To support this principle, we report in vitro radius-transmural pressure relations for a range of airway radii obtained from healthy bovine lungs and model the data using a strain energy function together with a thick-walled cylinder description. From this framework, we estimate circumferential stresses and incremental Young's moduli throughout the airway tree. Our results indicate that the conducting airways consistently operate within a preferred mechanical homeostatic state, termed mechanical homeostasis, that is characterized by a narrow range of circumferential stresses and Young's moduli. This mechanical homeostatic state is maintained for all airways throughout the tree via airway wall dimensional and mechanical relationships. As a consequence, cells within the airway walls throughout the airway tree experience similar oscillatory strains during breathing that are much smaller than previously thought. Finally, we discuss the potential implications of how the maintenance of mechanical homeostasis, while facilitating healthy tissue-level alterations necessary for maturation, may lead to airway wall structural changes capable of chronic asthma.

  13. A mechanical design principle for tissue structure and function in the airway tree.

    Directory of Open Access Journals (Sweden)

    Adam S LaPrad

    Full Text Available With every breath, the dynamically changing mechanical pressures must work in unison with the cells and soft tissue structures of the lung to permit air to efficiently traverse the airway tree and undergo gas exchange in the alveoli. The influence of mechanics on cell and tissue function is becoming apparent, raising the question: how does the airway tree co-exist within its mechanical environment to maintain normal cell function throughout its branching structure of diminishing dimensions? We introduce a new mechanical design principle for the conducting airway tree in which mechanotransduction at the level of cells is driven to orchestrate airway wall structural changes that can best maintain a preferred mechanical microenvironment. To support this principle, we report in vitro radius-transmural pressure relations for a range of airway radii obtained from healthy bovine lungs and model the data using a strain energy function together with a thick-walled cylinder description. From this framework, we estimate circumferential stresses and incremental Young's moduli throughout the airway tree. Our results indicate that the conducting airways consistently operate within a preferred mechanical homeostatic state, termed mechanical homeostasis, that is characterized by a narrow range of circumferential stresses and Young's moduli. This mechanical homeostatic state is maintained for all airways throughout the tree via airway wall dimensional and mechanical relationships. As a consequence, cells within the airway walls throughout the airway tree experience similar oscillatory strains during breathing that are much smaller than previously thought. Finally, we discuss the potential implications of how the maintenance of mechanical homeostasis, while facilitating healthy tissue-level alterations necessary for maturation, may lead to airway wall structural changes capable of chronic asthma.

  14. Airway pressure release ventilation and biphasic positive airway pressure: a systematic review of definitional criteria.

    Science.gov (United States)

    Rose, Louise; Hawkins, Martyn

    2008-10-01

    The objective of this study was to identify the definitional criteria for the pressure-limited and time-cycled modes: airway pressure release ventilation (APRV) and biphasic positive airway pressure (BIPAP) available in the published literature. Systematic review. Medline, PubMed, Cochrane, and CINAHL databases (1982-2006) were searched using the following terms: APRV, BIPAP, Bilevel and lung protective strategy, individually and in combination. Two independent reviewers determined the paper eligibility and abstracted data from 50 studies and 18 discussion articles. Of the 50 studies, 39 (78%) described APRV, and 11 (22%) described BIPAP. Various study designs, populations, or outcome measures were investigated. Compared to BIPAP, APRV was described more frequently as extreme inverse inspiratory:expiratory ratio [18/39 (46%) vs. 0/11 (0%), P = 0.004] and used rarely as a noninverse ratio [2/39 (5%) vs. 3/11 (27%), P = 0.06]. One (9%) BIPAP and eight (21%) APRV studies used mild inverse ratio (>1:1 to branding may further add to confusion. Generic naming of modes and consistent definitional parameters may improve consistency of patient response for a given mode and assist with clinical implementation.

  15. Mechanical breath profile of airway pressure release ventilation: the effect on alveolar recruitment and microstrain in acute lung injury.

    Science.gov (United States)

    Kollisch-Singule, Michaela; Emr, Bryanna; Smith, Bradford; Roy, Shreyas; Jain, Sumeet; Satalin, Joshua; Snyder, Kathy; Andrews, Penny; Habashi, Nader; Bates, Jason; Marx, William; Nieman, Gary; Gatto, Louis A

    2014-11-01

    Improper mechanical ventilation settings can exacerbate acute lung injury by causing a secondary ventilator-induced lung injury. It is therefore important to establish the mechanism by which the ventilator induces lung injury to develop protective ventilation strategies. It has been postulated that the mechanism of ventilator-induced lung injury is the result of heterogeneous, elevated strain on the pulmonary parenchyma. Acute lung injury has been associated with increases in whole-lung macrostrain, which is correlated with increased pathology. However, the effect of mechanical ventilation on alveolar microstrain remains unknown. To examine whether the mechanical breath profile of airway pressure release ventilation (APRV), consisting of a prolonged pressure-time profile and brief expiratory release phase, reduces microstrain. In a randomized, nonblinded laboratory animal study, rats were randomized into a controlled mandatory ventilation group (n = 3) and an APRV group (n = 3). Lung injury was induced by polysorbate lavage. A thoracotomy was performed and an in vivo microscope was placed on the lungs to measure alveolar mechanics. In the controlled mandatory ventilation group, multiple levels of positive end-expiratory pressure (PEEP; 5, 10, 16, 20, and 24 cm H2O) were tested. In the APRV group, decreasing durations of expiratory release (time at low pressure [T(low)]) were tested. The T(low) was set to achieve ratios of termination of peak expiratory flow rate (T-PEFR) to peak expiratory flow rate (PEFR) of 10%, 25%, 50%, and 75% (the smaller this ratio is [ie, 10%], the more time the lung is exposed to low pressure during the release phase, which decreases end-expiratory lung volume and potentiates derecruitment). Alveolar perimeters were measured at peak inspiration and end expiration using digital image analysis, and strain was calculated by normalizing the change in alveolar perimeter length to the original length. Macrostrain was measured by volume

  16. Negative pressure pulmonary oedema following use of ProSeal LMA

    Directory of Open Access Journals (Sweden)

    Richa Jain

    2013-01-01

    Full Text Available Negative pressure pulmonary oedema (NPPO is a life threatening condition, manifested due to upper airway obstruction in a spontaneously breathing patient. Upper airway obstruction caused by classic laryngeal mask airway (cLMA and ProSeal laryngeal mask airway (PLMA has been reported, and NPPO has also been reported following the use of cLMA. Search of literature did not confirm NPPO following the use of PLMA. We encountered a female patient of NPPO scheduled for incision and drainage of an abscess who had signs of airway obstruction following PLMA insertion. Multiple attempts were made to get patent airway without success. PLMA was replaced with endotracheal tube following which pink frothy secretion appeared in breathing circuit. Patient was managed successfully with ICU care.

  17. Upper airway resistance syndrome. Central electroencephalographic power and changes in breathing effort.

    Science.gov (United States)

    Black, J E; Guilleminault, C; Colrain, I M; Carrillo, O

    2000-08-01

    Upper airway resistance syndrome (UARS) is defined by excessive daytime sleepiness and tiredness, and is associated with increased breathing effort. Its polygraphic features involve progressive increases in esophageal pressure (Pes), terminated by arousal (AR) as defined by the American Sleep Disorders Association (ASDA). With the arousal there is an abrupt decrease in Pes, called Pes reversal. However, Pes reversal can be seen without the presence of an AR. We performed spectral analysis on electroencephalographic data from a central lead for both AR and nonarousal (N-AR) events obtained from 15 UARS patients (eight men and seven women). Delta band activity was increased before and surrounding Pes reversal regardless of the presence or absence of AR. In the period after Pes reversal, alpha, sigma, and beta activity showed a greater increase in AR events than in N-AR events. The Pes measures were identical leading up to the point of reversal, but showed a longer-lasting and significantly greater decrease in respiratory effort after an AR. The data indicate that substantial electroencephalographic changes can be identified in association with Pes events, even when ARs cannot be detected according to standard criteria; however, visually identifiable electroencephalographic arousals clearly have a greater impact on ongoing inspiratory effort.

  18. Supplemental Carbon Dioxide Stabilizes the Upper Airway in Volunteers Anesthetized with Propofol.

    Science.gov (United States)

    Ruscic, Katarina Jennifer; Bøgh Stokholm, Janne; Patlak, Johann; Deng, Hao; Simons, Jeroen Cedric Peter; Houle, Timothy; Peters, Jürgen; Eikermann, Matthias

    2018-05-10

    Propofol impairs upper airway dilator muscle tone and increases upper airway collapsibility. Preclinical studies show that carbon dioxide decreases propofol-mediated respiratory depression. We studied whether elevation of end-tidal carbon dioxide (PETCO2) via carbon dioxide insufflation reverses the airway collapsibility (primary hypothesis) and impaired genioglossus muscle electromyogram that accompany propofol anesthesia. We present a prespecified, secondary analysis of previously published experiments in 12 volunteers breathing via a high-flow respiratory circuit used to control upper airway pressure under propofol anesthesia at two levels, with the deep level titrated to suppression of motor response. Ventilation, mask pressure, negative pharyngeal pressure, upper airway closing pressure, genioglossus electromyogram, bispectral index, and change in end-expiratory lung volume were measured as a function of elevation of PETCO2 above baseline and depth of propofol anesthesia. PETCO2 augmentation dose-dependently lowered upper airway closing pressure with a decrease of 3.1 cm H2O (95% CI, 2.2 to 3.9; P < 0.001) under deep anesthesia, indicating improved upper airway stability. In parallel, the phasic genioglossus electromyogram increased by 28% (23 to 34; P < 0.001). We found that genioglossus electromyogram activity was a significant modifier of the effect of PETCO2 elevation on closing pressure (P = 0.005 for interaction term). Upper airway collapsibility induced by propofol anesthesia can be reversed in a dose-dependent manner by insufflation of supplemental carbon dioxide. This effect is at least partly mediated by increased genioglossus muscle activity.

  19. Improvised bubble continuous positive airway pressure (BCPAP ...

    African Journals Online (AJOL)

    Improvised bubble continuous positive airway pressure (BCPAP) device at the National Hospital Abuja gives immediate improvement in respiratory rate and oxygenation in neonates with respiratory distress.

  20. Exploring Airway Diseases by NMR-Based Metabonomics: A Review of Application to Exhaled Breath Condensate

    Directory of Open Access Journals (Sweden)

    Matteo Sofia

    2011-01-01

    Full Text Available There is increasing evidence that biomarkers of exhaled gases or exhaled breath condensate (EBC may help in detecting abnormalities in respiratory diseases mirroring increased, oxidative stress, airways inflammation and endothelial dysfunction. Beside the traditional techniques to investigate biomarker profiles, “omics” sciences have raised interest in the clinical field as potentially improving disease phenotyping. In particular, metabonomics appears to be an important tool to gain qualitative and quantitative information on low-molecular weight metabolites present in cells, tissues, and fluids. Here, we review the potential use of EBC as a suitable matrix for metabonomic studies using nuclear magnetic resonance (NMR spectroscopy. By using this approach in airway diseases, it is now possible to separate specific EBC profiles, with implication in disease phenotyping and personalized therapy.

  1. Continuous Positive Airway Pressure During Exercise Improves Walking Time in Patients Undergoing Inpatient Cardiac Rehabilitation After Coronary Artery Bypass Graft Surgery: A RANDOMIZED CONTROLLED TRIAL.

    Science.gov (United States)

    Pantoni, Camila Bianca Falasco; Di Thommazo-Luporini, Luciana; Mendes, Renata Gonçalves; Caruso, Flávia Cristina Rossi; Mezzalira, Daniel; Arena, Ross; Amaral-Neto, Othon; Catai, Aparecida Maria; Borghi-Silva, Audrey

    2016-01-01

    Continuous positive airway pressure (CPAP) has been used as an effective support to decrease the negative pulmonary effects of coronary artery bypass graft (CABG) surgery. However, it is unknown whether CPAP can positively influence patients undergoing CABG during exercise. This study evaluated the effectiveness of CPAP on the first day of ambulation after CABG in patients undergoing inpatient cardiac rehabilitation (CR). Fifty-four patients after CABG surgery were randomly assigned to receive either inpatient CR and CPAP (CPG) or standard CR without CPAP (CG). Cardiac rehabilitation included walking and CPAP pressures were set between 10 to 12 cmH2O. Participants were assessed on the first day of walking at rest and during walking. Outcome measures included breathing pattern variables, exercise time in seconds (ETs), dyspnea/leg effort ratings, and peripheral oxygen saturation (SpO2). Twenty-seven patients (13 CPG vs 14 CG) completed the study. Compared with walking without noninvasive ventilation assistance, CPAP increased ETs by 43.4 seconds (P = .040) during walking, promoted better thoracoabdominal coordination, increased ventilation during walking by 12.5 L/min (P = .001), increased SpO2 values at the end of walking by 2.6% (P = .016), and reduced dyspnea ratings by 1 point (P = .008). Continuous positive airway pressure can positively influence exercise tolerance, ventilatory function, and breathing pattern in response to a single bout of exercise after CABG.

  2. Continuous positive airway pressure therapy: new generations.

    LENUS (Irish Health Repository)

    Garvey, John F

    2010-02-01

    Continuous positive airway pressure (CPAP) is the treatment of choice for obstructive sleep apnoea syndrome (OSAS). However, CPAP is not tolerated by all patients with OSAS and alternative modes of pressure delivery have been developed to overcome pressure intolerance, thereby improving patient comfort and adherence. Auto-adjustable positive airway pressure (APAP) devices may be utilised for the long-term management of OSAS and may also assist in the initial diagnosis of OSAS and titration of conventional CPAP therapy. Newer modalities such as C-Flex and A-Flex also show promise as treatment options in the future. However, the evidence supporting the use of these alternative modalities remains scant, in particular with regard to long-term cardiovascular outcomes. In addition, not all APAP devices use the same technological algorithms and data supporting individual APAP devices cannot be extrapolated to support all. Further studies are required to validate the roles of APAP, C-Flex and A-Flex. In the interim, standard CPAP therapy should continue as the mainstay of OSAS management.

  3. Continuous positive airway pressure therapy: new generations.

    LENUS (Irish Health Repository)

    Garvey, John F

    2012-02-01

    Continuous positive airway pressure (CPAP) is the treatment of choice for obstructive sleep apnoea syndrome (OSAS). However, CPAP is not tolerated by all patients with OSAS and alternative modes of pressure delivery have been developed to overcome pressure intolerance, thereby improving patient comfort and adherence. Auto-adjustable positive airway pressure (APAP) devices may be utilised for the long-term management of OSAS and may also assist in the initial diagnosis of OSAS and titration of conventional CPAP therapy. Newer modalities such as C-Flex and A-Flex also show promise as treatment options in the future. However, the evidence supporting the use of these alternative modalities remains scant, in particular with regard to long-term cardiovascular outcomes. In addition, not all APAP devices use the same technological algorithms and data supporting individual APAP devices cannot be extrapolated to support all. Further studies are required to validate the roles of APAP, C-Flex and A-Flex. In the interim, standard CPAP therapy should continue as the mainstay of OSAS management.

  4. Moderately high frequency ventilation with a conventional ventilator allows reduction of tidal volume without increasing mean airway pressure.

    Science.gov (United States)

    Cordioli, Ricardo Luiz; Park, Marcelo; Costa, Eduardo Leite Vieira; Gomes, Susimeire; Brochard, Laurent; Amato, Marcelo Britto Passos; Azevedo, Luciano Cesar Pontes

    2014-12-01

    The aim of this study was to explore if positive-pressure ventilation delivered by a conventional ICU ventilator at a moderately high frequency (HFPPV) allows a safe reduction of tidal volume (V T) below 6 mL/kg in a porcine model of severe acute respiratory distress syndrome (ARDS) and at a lower mean airway pressure than high-frequency oscillatory ventilation (HFOV). This is a prospective study. In eight pigs (median weight 34 [29,36] kg), ARDS was induced by pulmonary lavage and injurious ventilation. The animals were ventilated with a randomized sequence of respiratory rates: 30, 60, 90, 120, 150, followed by HFOV at 5 Hz. At each step, V T was adjusted to allow partial pressure of arterial carbon dioxide (PaCO2) to stabilize between 57 and 63 mmHg. Data are shown as median [P25th,P75th]. After lung injury, the PaO2/FiO2 (P/F) ratio was 92 [63,118] mmHg, pulmonary shunt 26 [17,31]%, and static compliance 11 [8,14] mL/cmH2O. Positive end-expiratory pressure (PEEP) was 14 [10,17] cmH2O. At 30 breaths/min, V T was higher than 6 (7.5 [6.8,10.2]) mL/kg, but at all higher frequencies, V T could be reduced and PaCO2 maintained, leading to reductions in plateau pressures and driving pressures. For frequencies of 60 to 150/min, V T progressively fell from 5.2 [5.1,5.9] to 3.8 [3.7,4.2] mL/kg (p mechanics, auto-PEEP generation, hemodynamics, or gas exchange. Mean airway pressure was maintained constant and was increased only during HFOV. During protective mechanical ventilation, HFPPV delivered by a conventional ventilator in a severe ARDS swine model safely allows further tidal volume reductions. This strategy also allowed decreasing airway pressures while maintaining stable PaCO2 levels.

  5. Comparison of Efficacy and Tolerance of Automatic Continuous Positive Airway Pressure Devices With the Optimum Continuous Positive Airway Pressure.

    Science.gov (United States)

    Tommi, George; Aronow, Wilbert S; Sheehan, John C; McCleay, Matthew T; Meyers, Patrick G

    Patients diagnosed with obstructive sleep apnea syndrome were randomly placed on automatic continuous positive airway pressure (ACPAP) for 2 hours followed by manual titration for the rest of the night. One hundred sixty-one patients entered the study, with at least 50 patients titrated with each of 3 ACPAP devices. The optimum continuous positive airway pressure (CPAP) was defined as the lowest pressure with an apnea-hypoxia index of ≤5/hr, which ranged from 4 cm to 18 cm. Success with ACPAP was approximately 60%-80% when the optimum CPAP was 4-6 cm but fell to below 30% if the optimum CPAP was ≥8 cm (P = 0.001). Average ACPAP ranged from 2 to 10 cm below the optimum level if the optimum CPAP was ≥8 cm. Patients who responded to a low CPAP but deteriorated on higher pressures failed to respond to any of the automatic devices. We recommend that CPAP titration be performed manually before initiation of ACPAP in patients with obstructive sleep apnea. The basal pressure for ACPAP should be the optimum pressure obtained by manual titration. Limits on the upper level of ACPAP may be necessary for patients who deteriorate on higher positive pressures.

  6. A 4DCT imaging-based breathing lung model with relative hysteresis

    Energy Technology Data Exchange (ETDEWEB)

    Miyawaki, Shinjiro; Choi, Sanghun [IIHR – Hydroscience & Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Hoffman, Eric A. [Department of Biomedical Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Medicine, The University of Iowa, Iowa City, IA 52242 (United States); Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Lin, Ching-Long, E-mail: ching-long-lin@uiowa.edu [IIHR – Hydroscience & Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Mechanical and Industrial Engineering, The University of Iowa, 3131 Seamans Center, Iowa City, IA 52242 (United States)

    2016-12-01

    To reproduce realistic airway motion and airflow, the authors developed a deforming lung computational fluid dynamics (CFD) model based on four-dimensional (4D, space and time) dynamic computed tomography (CT) images. A total of 13 time points within controlled tidal volume respiration were used to account for realistic and irregular lung motion in human volunteers. Because of the irregular motion of 4DCT-based airways, we identified an optimal interpolation method for airway surface deformation during respiration, and implemented a computational solid mechanics-based moving mesh algorithm to produce smooth deforming airway mesh. In addition, we developed physiologically realistic airflow boundary conditions for both models based on multiple images and a single image. Furthermore, we examined simplified models based on one or two dynamic or static images. By comparing these simplified models with the model based on 13 dynamic images, we investigated the effects of relative hysteresis of lung structure with respect to lung volume, lung deformation, and imaging methods, i.e., dynamic vs. static scans, on CFD-predicted pressure drop. The effect of imaging method on pressure drop was 24 percentage points due to the differences in airflow distribution and airway geometry. - Highlights: • We developed a breathing human lung CFD model based on 4D-dynamic CT images. • The 4DCT-based breathing lung model is able to capture lung relative hysteresis. • A new boundary condition for lung model based on one static CT image was proposed. • The difference between lung models based on 4D and static CT images was quantified.

  7. Airway obstruction and gas leak during mask ventilation of preterm infants in the delivery room.

    LENUS (Irish Health Repository)

    2011-07-01

    Preterm infants with inadequate breathing receive positive pressure ventilation (PPV) by mask with variable success. The authors examined recordings of PPV given to preterm infants in the delivery room for prevalence of mask leak and airway obstruction.

  8. Association of Lung Inflammatory Cells with Small Airways Function and Exhaled Breath Markers in Smokers - Is There a Specific Role for Mast Cells?

    Directory of Open Access Journals (Sweden)

    Yvonne Nussbaumer-Ochsner

    Full Text Available Smoking is associated with a mixed inflammatory infiltrate in the airways. We evaluated whether airway inflammation in smokers is related to lung function parameters and inflammatory markers in exhaled breath.Thirty-seven smokers undergoing lung resection for primary lung cancer were assessed pre-operatively by lung function testing including single-breath-nitrogen washout test (sb-N2-test, measurement of fractional exhaled nitric oxide (FeNO and pH/8-isoprostane in exhaled breath condensate (EBC. Lung tissue sections containing cancer-free large (LA and small airways (SA were stained for inflammatory cells. Mucosal (MCT respectively connective tissue mast cells (MCTC and interleukin-17A (IL-17A expression by mast cells was analysed using a double-staining protocol.The median number of neutrophils, macrophages and mast cells infiltrating the lamina propria and adventitia of SA was higher than in LA. Both MCTC and MCT were higher in the lamina propria of SA compared to LA (MCTC: 49 vs. 27.4 cells/mm2; MCT: 162.5 vs. 35.4 cells/mm2; P<0.005 for both instances. IL-17A expression was predominantly detected in MCTC of LA. Significant correlations were found for the slope of phase III % pred. of the sb-N2-test (rs= -0.39, for the FEV1% pred. (rs= 0.37 and for FEV1/FVC ratio (rs=0.38 with MCT in SA (P<0.05 for all instances. 8-isoprostane concentration correlated with the mast cells in the SA (rs=0.44, there was no correlation for pH or FeNO with cellular distribution in SA.Neutrophils, macrophages and mast cells are more prominent in the SA indicating that these cells are involved in the development of small airway dysfunction in smokers. Among these cell types, the best correlation was found for mast cells with lung function parameters and inflammatory markers in exhaled breath. Furthermore, the observed predominant expression of IL-17A in mast cells warrants further investigation to elucidate their role in smoking-induced lung injury, despite the

  9. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... specialized CF care and a range of treatment options. Airway Clearance Active Cycle of Breathing Technique Airway ... on their own. Share Facebook Twitter Email More options Print Share Facebook Twitter Email Print Permalink All ...

  10. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... a range of treatment options. Airway Clearance Active Cycle of Breathing Technique Airway Clearance Techniques Autogenic Drainage ... LEGACY GIFT Sponsor a Participant CF Climb CF Cycle for Life Great Strides Xtreme Hike Participate In ...

  11. Exhaled breath condensate cysteinyl leukotrienes and airway remodeling in childhood asthma: a pilot study

    Directory of Open Access Journals (Sweden)

    Kharitonov Sergei A

    2006-04-01

    Full Text Available Abstract Background It has been suggested that cysteinyl leukotrienes (cysLTs play an important role in airway remodeling. Previous reports have indicated that cysLTs augment human airway smooth muscle cell proliferation. Recently, cysLTs have been measured in exhaled breath condensate (EBC. The aim of this study was to evaluate the relationship between cysLTs in EBC and another marker of airway remodeling, reticular basement membrane (RBM thickening, in endobronchial biopsies in children. Methods 29 children, aged 4–15 years, with moderate to severe persistent asthma, who underwent bronchoscopy as part of their clinical assessment, were included. Subjects underwent spirometry and EBC collection for cysLTs analysis, followed by bronchoscopy and endobronchial biopsy within 24 hours. Results EBC cysLTs were significantly lower in asthmatic children who were treated with montelukast than in those who were not (median (interquartile range 36.62 (22.60–101.05 versus 249.1 (74.21–526.36 pg/ml, p = 0.004. There was a significant relationship between EBC cysLTs and RBM thickness in the subgroup of children who were not treated with montelukast (n = 13, r = 0.75, p = 0.003. Conclusion EBC cysLTs appear to be associated with RBM thickening in asthma.

  12. Numerical Simulation for Mechanism of Airway Narrowing in Asthma

    Science.gov (United States)

    Bando, Kiyoshi; Yamashita, Daisuke; Ohba, Kenkichi

    A calculation model is proposed to examine the generation mechanism of the numerous lobes on the inner-wall of the airway in asthmatic patients and to clarify luminal occlusion of the airway inducing breathing difficulties. The basement membrane in the airway wall is modeled as a two-dimensional thin-walled shell having inertia force due to the mass, and the smooth muscle contraction effect is replaced by uniform transmural pressure applied to the basement membrane. A dynamic explicit finite element method is used as a numerical simulation method. To examine the validity of the present model, simulation of an asthma attack is performed. The number of lobes generated in the basement membrane increases when transmural pressure is applied in a shorter time period. When the remodeling of the basement membrane occurs characterized by thickening and hardening, it is demonstrated that the number of lobes decreases and the narrowing of the airway lumen becomes severe. Comparison of the results calculated by the present model with those measured for animal experiments of asthma will be possible.

  13. Improvised bubble continuous positive airway pressure

    African Journals Online (AJOL)

    PROF. EZECHUKWU

    2014-08-15

    Aug 15, 2014 ... Abstract: Background: Prematur- ity accounts for 25% of Neonatal mortality in Nigeria and Respira- tory Distress Syndrome is respon- sible for half of these deaths. Introducing continuous positive airway pressure for the treatment of RDS in Nigeria where health care financing is predominantly out-of-pocket ...

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

    Directory of Open Access Journals (Sweden)

    Yesim Bayraktar

    2013-06-01

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

  15. Use of Respiratory Support in the Biphase Ventilation Airway Mode in the Newborn

    Directory of Open Access Journals (Sweden)

    S. N. Koval

    2006-01-01

    Full Text Available Biphasic positive airway pressure (BIPAP (also known as DuoPAP, BiLevel, BiVent, PCV+, SPAP is a mode of ventilation with cycling variations between two continuous positive airway pressure levels. It is a mixture of pressure controlled ventilation and spontaneous breathing, which is unrestricted in each phase of the respiratory cycle. The volume displacement caused by the difference between Phigh and Plow airway pressure level. The phase time ratio (PTR — the BIPAP frequency is calculated as the ratio between the durations of the two pressure phases, a PTR greater than 1:1 is called APRV (airway pressure release ventilation. In patients with ARDS maintained spontaneous breathing with BIPAP resulted in lower venous admixture and better arterial blood oxygenation as compared with A/C. Only a few studies with BIPAP have been performed in newborn and infants until now. We studied the use of BIPAP in newborn (body mass > 3kg and randomised 40 patients with respiratory failure for ventilation with BIPAP (n=20 or conventional mechanical ventilatory support (assist-control A/C — synchronised intermittent mandatory ventilation (SIMV (n=20. The Pediatric Risk of Mortality score (PRISM were collected for each patient. Fentanyl, diazepam, GABA were used as sedatives and adjusted in accordance with the Cook scale. We compared ventilatory parameters, information pertaining to pulmonary function and oxygen delivery, cardiac output, additional descriptors of organ system functions, duration and complications of ventilation and number and dosages of sedatives administered. All the patients that we intended to ventilate with BIPAP were successfully ventilated, we can conclude that biphasic ventilatory support suitable mode of ventilation for newborn with a decreased need of analgetics and sedatives than A/C. Finally, BIPAP is an a effective safe, and easy to use for personal mode of mechanical ventilatory support in newborn. 

  16. EXTUBATE: A randomised controlled trial of nasal biphasic positive airway pressure vs. nasal continuous positive airway pressure following extubation in infants less than 30 weeks' gestation: study protocol for a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Victor Suresh

    2011-12-01

    Full Text Available Abstract Background Respiratory distress syndrome remains a significant problem among premature infants. Mechanical ventilation through an endotracheal tube remains the mainstay of respiratory support but may be associated with lung injury and the development of chronic lung disease of prematurity. Efforts are needed to reduce the duration of mechanical ventilation in favour of less invasive forms of respiratory support and to improve rates of successful extubation. Non-invasive respiratory support has been demonstrated to be less injurious to the premature lung. Standard practice is to use nasal continuous positive airway pressure (n-CPAP following extubation to support the baby's breathing. Many clinicians also use nasal biphasic positive airway pressure (n-BiPAP in efforts to improve rates of successful extubation. However, there is currently no evidence that this confers any advantage over conventional nasal continuous positive airway pressure. Methods We propose an unblinded multi-centre randomised trial comparing n-CPAP with n-BiPAP in babies born before 30 weeks' gestation and less than two weeks old. Babies with congenital abnormalities and severe intra-ventricular haemorrhage will be excluded. 540 babies admitted to neonatal centres in England will be randomised at the time of first extubation attempt. The primary aim of this study is to compare the rate of extubation failure within 48 hours following the first attempt at extubation. The secondary aims are to compare the effect of n-BiPAP and n-CPAP on the following outcomes: 1. Maintenance of successful extubation for 7 days post extubation 2. Oxygen requirement at 28 days of age and at 36 weeks' corrected gestational age 3. Total days on ventilator, n-CPAP/n-BiPAP 4. Number of ventilator days following first extubation attempt 5. pH and partial pressure of carbon dioxide in the first post extubation blood gas 6. Duration of hospital stay 7. Rate of abdominal distension requiring

  17. The Effect of Sleep Disordered Breathing on the Outcome of Stroke and Transient Ischemic Attack

    DEFF Research Database (Denmark)

    Birkbak, Johannes; Clark, Alice J; Rod, Naja Hulvej

    2014-01-01

    The primary objective was to systematically review the literature on how sleep disordered breathing (SDB) affects recurrence and death among stroke or transient ischemic attack (TIA) patients. A secondary objective was to evaluate how treatment of SDB with continuous positive airway pressure (CPAP...

  18. Verifying the Relative Efficacy between Continuous Positive Airway Pressure Therapy and Its Alternatives for Obstructive Sleep Apnea: A Network Meta-analysis

    Directory of Open Access Journals (Sweden)

    Tingwei Liu

    2017-06-01

    Full Text Available Obstructive sleep apnea (OSA is a common breathing disorder, and continuous positive airway pressure (CPAP therapy together with its alternatives has been developed to treat this disease. This network meta-analysis (NMA was aimed to compare the efficacy of treatments for OSA. Cochrane Library, MEDLINE, and Embase were searched for eligible studies. A conventional and NMA was carried out to compare all therapies. Sleeping characteristics, including Apnea–Hypopnea Index (AHI, Epworth Sleepiness Scale (ESS, arterial oxygen saturation, and arousal index (AI, and changes of blood pressure were selected as outcomes. A total of 84 studies were finally included after rigorous screenings. For the primary outcomes of AHI and ESS, the value of auto-adjusting positive airway pressure (APAP, CPAP, and oral appliance (OA all showed statistically reduction compared with inactive control (IC. Similar observation was obtained in AI, with treatments of the three active interventions. A lower effect of IC in SaO2 was exhibited when compared with APAP, CPAP, and OA. Similar statistically significant results were presented in 24 h systolic blood pressure and 24 h DBP when comparing with CPAP. Our NMA identified CPAP as the most efficacious treatment for OSA patients after the evaluation of sleeping characteristics and blood pressures. In addition, more clinical trials are needed for further investigation due to the existence of inconsistency observed in this study.

  19. Work of breathing using different interfaces in spontaneous positive pressure ventilation: helmet, face-mask, and endotracheal tube.

    Science.gov (United States)

    Oda, Shinya; Otaki, Kei; Yashima, Nozomi; Kurota, Misato; Matsushita, Sachiko; Kumasaka, Airi; Kurihara, Hutaba; Kawamae, Kaneyuki

    2016-08-01

    Noninvasive positive pressure ventilation (NPPV) using a helmet is expected to cause inspiratory trigger delay due to the large collapsible and compliant chamber. We compared the work of breathing (WOB) of NPPV using a helmet or a full face-mask with that of invasive ventilation by tracheal intubation. We used a lung model capable of simulating spontaneous breathing (LUNGOO; Air Water Inc., Japan). LUNGOO was set at compliance (C) = 50 mL/cmH2O and resistance (R) = 5 cmH2O/L/s for normal lung simulation, C = 20 mL/cmH2O and R = 5 cmH2O/L/s for restrictive lung, and C = 50 mL/cmH2O and R = 20 cmH2O/L/s for obstructive lung. Muscle pressure was fixed at 25 cmH2O and respiratory rate at 20 bpm. Pressure support ventilation and continuous positive airway pressure were performed with each interface placed on a dummy head made of reinforced plastic that was connected to LUNGOO. We tested the inspiratory WOB difference between the interfaces with various combinations of ventilator settings (positive end-expiratory pressure 5 cmH2O; pressure support 0, 5, and 10 cmH2O). In the normal lung and restrictive lung models, WOB decreased more with the face-mask than the helmet, especially when accompanied by the level of pressure support. In the obstructive lung model, WOB with the helmet decreased compared with the other two interfaces. In the mixed lung model, there were no significant differences in WOB between the three interfaces. NPPV using a helmet is more effective than the other interfaces for WOB in obstructive lung disease.

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

    Science.gov (United States)

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

    2017-04-01

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

  1. Synchronized imaging and acoustic analysis of the upper airway in patients with sleep-disordered breathing

    International Nuclear Information System (INIS)

    Chang, Yi-Chung; Pham, Van-Truong; Wang, Yung-Hung; Lin, Chen; Lo, Men-Tzung; Huon, Leh-Kiong; Wang, Pa-Chun; Chen, Yunn-Jy; Jiang, Sun-Fen; Shih, Tiffany Ting-Fang; Tran, Thi-Thao; Tsao, Jenho

    2014-01-01

    Progressive narrowing of the upper airway increases airflow resistance and can produce snoring sounds and apnea/hypopnea events associated with sleep-disordered breathing due to airway collapse. Recent studies have shown that acoustic properties during snoring can be altered with anatomic changes at the site of obstruction. To evaluate the instantaneous association between acoustic features of snoring and the anatomic sites of obstruction, a novel method was developed and applied in nine patients to extract the snoring sounds during sleep while performing dynamic magnetic resonance imaging (MRI). The degree of airway narrowing during the snoring events was then quantified by the collapse index (ratio of airway diameter preceding and during the events) and correlated with the synchronized acoustic features. A total of 201 snoring events (102 pure retropalatal and 99 combined retropalatal and retroglossal events) were recorded, and the collapse index as well as the soft tissue vibration time were significantly different between pure retropalatal (collapse index, 24  ±  11%; vibration time, 0.2  ±  0.3 s) and combined (retropalatal and retroglossal) snores (collapse index, 13  ±  7% [P ≤ 0.0001]; vibration time, 1.2  ±  0.7 s [P ≤ 0.0001]). The synchronized dynamic MRI and acoustic recordings successfully characterized the sites of obstruction and established the dynamic relationship between the anatomic site of obstruction and snoring acoustics. (paper)

  2. Home continuous positive airway pressure for cardiopulmonary indications in infants and children.

    Science.gov (United States)

    Al-Iede, Montaha; Kumaran, Radhagini; Waters, Karen

    2018-04-30

    A number of reports exist regarding the use of continuous positive airway pressure (CPAP) to manage obstructive sleep apnoea (OSA) in children, which we term 'conventional CPAP'. In contrast, there are few reports of home CPAP use for other indications, which we have grouped under the term 'cardiopulmonary'. The aims of this study were to (1) document cardiopulmonary indications for CPAP use in a cohort of infants and children, and (2) evaluate its effectiveness in this group. Hospital records were reviewed for 645 patients who were commenced on long-term CPAP over a 10-year period at a single-tertiary hospital (Children's Hospital at Westmead). This study evaluated the group where the primary indication for CPAP was not OSA ('cardiopulmonary CPAP'). Data evaluated included: demographics, diagnoses, indications for CPAP, hours of use (compliance) and sleep study results at baseline and on CPAP. Of 645 children, 148 (23%) used home CPAP for cardiopulmonary indications; and 130 (87.8%) of these were included. For this group, mean age at CPAP initiation was 18.6 ± 33.6 months (range one week to 16.8 years). Cardiopulmonary indications for CPAP use included: primary airway diseases 65 (50%), chronic lung diseases 33 (25.4%), congenital heart disease (CHD) 20 (15.4%), and both CHD and airway malacia 12 (9.2%). All sleep study variables improved on CPAP relative to the diagnostic sleep study (p 4 h/night). Interstitial lung diseases and other cardiorespiratory disorders, often of congenital origin, can be effectively treated with home CPAP whether they are associated with OSA or not. Sleep studies demonstrated improved gas exchange, sleep and reduced work of breathing with CPAP use. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Effect of oxygenation on breath-by-breath response of the genioglossus muscle during occlusion.

    Science.gov (United States)

    Gauda, E B; Carroll, J L; McColley, S; Smith, P L

    1991-10-01

    We investigated the effect of different levels of O2 tension (hypoxia, normoxia, and hyperoxia) on the breath-by-breath onset and peak electromyographic (EMG) activity of the genioglossus (GG) muscle during a five-breath end-expiratory tracheal occlusion of 20- to 30-s duration. GG and diaphragmatic (DIA) EMG activity were measured with needle electrodes in eight anesthetized tracheotomized adult cats. In response to occlusion, the increase in the number of animals with GG EMG activity was different during hypoxia, normoxia, and hyperoxia (P = 0.003, Friedman). During hypoxia, eight of eight of the animals had GG EMG activity by the third occluded effort. In contrast, during normoxia, only four of eight and, during hyperoxia, only three of eight animals had GG EMG activity throughout the entire five-breath occlusion. Similarly, at release of the occlusion, more animals had persistent GG EMG activity on the postocclusion breaths during hypoxia than during normoxia or hyperoxia. Breath-by-breath augmentation of peak amplitude of the GG and DIA EMGs on each occluded effort was accentuated during hypoxia (P less than 0.01) and abolished during hyperoxia (P = 0.10). These results suggest that hypoxemia is a major determinant of the rapidity of onset, magnitude, and sustained activity of upper airway muscles during airway occlusion.

  4. Control of upper airway muscle activity in younger versus older men during sleep onset

    Science.gov (United States)

    Fogel, Robert B; White, David P; Pierce, Robert J; Malhotra, Atul; Edwards, Jill K; Dunai, Judy; Kleverlaan, Darci; Trinder, John

    2003-01-01

    Pharyngeal dilator muscles are clearly important in the pathophysiology of obstructive sleep apnoea syndrome (OSA). We have previously shown that the activity of both the genioglossus (GGEMG) and tensor palatini (TPEMG) are decreased at sleep onset, and that this decrement in muscle activity is greater in the apnoea patient than in healthy controls. We have also previously shown this decrement to be greater in older men when compared with younger ones. In order to explore the mechanisms responsible for this decrement in muscle activity nasal continuous positive airway pressure (CPAP) was applied to reduce negative pressure mediated muscle activation. We then investigated the effect of sleep onset (transition from predominantly α to predominantly θ EEG activity) on ventilation, upper airway muscle activation and upper airway resistance (UAR) in middle-aged and younger healthy men. We found that both GGEMG and TPEMG were reduced by the application of nasal CPAP during wakefulness, but that CPAP did not alter the decrement in activity in either muscle seen in the first two breaths following an α to θ transition. However, CPAP prevented both the rise in UAR at sleep onset that occurred on the control night, and the recruitment in GGEMG seen in the third to fifth breaths following the α to θ transition. Further, GGEMG was higher in the middle-aged men than in the younger men during wakefulness and was decreased more in the middle-aged men with the application of nasal CPAP. No differences were seen in TPEMG between the two age groups. These data suggest that the initial sleep onset reduction in upper airway muscle activity is due to loss of a ‘wakefulness’ stimulus, rather than to loss of responsiveness to negative pressure. In addition, it suggests that in older men, higher wakeful muscle activity is due to an anatomically more collapsible upper airway with more negative pressure driven muscle activation. Sleep onset per se does not appear to have a greater

  5. Can resistive breathing injure the lung? Implications for COPD exacerbations

    Directory of Open Access Journals (Sweden)

    Vassilakopoulos T

    2016-09-01

    Full Text Available Theodoros Vassilakopoulos, Dimitrios Toumpanakis Pulmonary and Critical Care Medicine, Medical School, National and Kapodistrian University of Athens, Greece Abstract: In obstructive lung diseases, airway inflammation leads to bronchospasm and thus resistive breathing, especially during exacerbations. This commentary discusses experimental evidence that resistive breathing per se (the mechanical stimulus in the absence of underlying airway inflammation leads to lung injury and inflammation (mechanotransduction. The potential implications of resistive breathing-induced mechanotrasduction in COPD exacerbations are presented along with the available clinical evidence. Keywords: resistive breathing, COPD, mechanotransduction, bronchoconstriction, inflammation

  6. A novel animal model for hyperdynamic airway collapse.

    Science.gov (United States)

    Tsukada, Hisashi; O'Donnell, Carl R; Garland, Robert; Herth, Felix; Decamp, Malcolm; Ernst, Armin

    2010-12-01

    Tracheobronchomalacia (TBM) is increasingly recognized as a condition associated with significant pulmonary morbidity. However, treatment is invasive and complex, and because there is no appropriate animal model, novel diagnostic and treatment strategies are difficult to evaluate. We endeavored to develop a reliable airway model to simulate hyperdynamic airway collapse in humans. Seven 20-kg male sheep were enrolled in this study. Tracheomalacia was created by submucosal resection of > 50% of the circumference of 10 consecutive cervical tracheal cartilage rings through a midline cervical incision. A silicone stent was placed in the trachea to prevent airway collapse during recovery. Tracheal collapsibility was assessed at protocol-specific time points by bronchoscopy and multidetector CT imaging while temporarily removing the stent. Esophageal pressure and flow data were collected to assess flow limitation during spontaneous breathing. All animals tolerated the surgical procedure well and were stented without complications. One sheep died at 2 weeks because of respiratory failure related to stent migration. In all sheep, near-total forced inspiratory airway collapse was observed up to 3 months postprocedure. Esophageal manometry demonstrated flow limitation associated with large negative pleural pressure swings during rapid spontaneous inhalation. Hyperdynamic airway collapse can reliably be induced with this technique. It may serve as a model for evaluation of novel diagnostic and therapeutic strategies for TBM.

  7. Treatment of upper airway resistance syndrome in adults: Where do we stand?

    Directory of Open Access Journals (Sweden)

    Luciana B.M. de Godoy

    2015-01-01

    Full Text Available Objective: To evaluate the available literature regarding Upper Airway Resistance Syndrome (UARS treatment. Methods: Keywords “Upper Airway Resistance Syndrome,” “Sleep-related Breathing Disorder treatment,” “Obstructive Sleep Apnea treatment” and “flow limitation and sleep” were used in main databases. Results: We found 27 articles describing UARS treatment. Nasal continuous positive airway pressure (CPAP has been the mainstay therapy prescribed but with limited effectiveness. Studies about surgical treatments had methodological limitations. Oral appliances seem to be effective but their efficacy is not yet established. Conclusion: Randomized controlled trials with larger numbers of patients and long-term follow-up are important to establish UARS treatment options.

  8. Responses to negative pressure surrounding the neck in anesthetized animals.

    Science.gov (United States)

    Wolin, A D; Strohl, K P; Acree, B N; Fouke, J M

    1990-01-01

    Continuous positive pressure applied at the nose has been shown to cause a decrease in upper airway resistance. The present study was designed to determine whether a similar positive transmural pressure gradient, generated by applying a negative pressure at the body surface around the neck, altered upper airway patency. Studies were performed in nine spontaneously breathing anesthetized supine dogs. Airflow was measured with a pneumotachograph mounted on an airtight muzzle placed over the nose and mouth of each animal. Upper airway pressure was measured as the differential pressure between the extrathoracic trachea and the inside of the muzzle. Upper airway resistance was monitored as an index of airway patency. Negative pressure (-2 to -20 cmH2O) was applied around the neck by using a cuirass extending from the jaw to the thorax. In each animal, increasingly negative pressures were transmitted to the airway wall in a progressive, although not linear, fashion. Decreasing the pressure produced a progressive fall in upper airway resistance, without causing a significant change in respiratory drive or respiratory timing. At -5 cmH2O pressure, there occurred a significant fall in upper airway resistance, comparable with the response of a single, intravenous injection of sodium cyanide (0.5-3.0 mg), a respiratory stimulant that produces substantial increases in respiratory drive. We conclude that upper airway resistance is influenced by the transmural pressure across the airway wall and that such a gradient can be accomplished by making the extraluminal pressure more negative.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    Science.gov (United States)

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

    2018-01-15

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

  10. Impediment in upper airway stabilizing forces assessed by phrenic nerve stimulation in sleep apnea patients

    Directory of Open Access Journals (Sweden)

    Vérin E

    2005-09-01

    Full Text Available Abstract Background The forces developed during inspiration play a key role in determining upper airway stability and the occurrence of nocturnal breathing disorders. Phrenic nerve stimulation applied during wakefulness is a unique tool to assess Upper airway dynamic properties and to measure the overall mechanical effects of the inspiratory process on UA stability. Objectives To compare the flow/pressure responses to inspiratory and expiratory twitches between sleep apnea subjects and normal subjects. Methods Inspiratory and expiratory twitches using magnetic nerve stimulation completed in eleven untreated sleep apnea subjects and ten normal subjects. Results In both groups, higher flow and pressure were reached during inspiratory twitches. The two groups showed no differences in expiratory twitch parameters. During inspiration, the pressure at which flow-limitation occurred was more negative in normals than in apneic subjects, but not reaching significance (p = 0.07. The relationship between pharyngeal pressure and flow adequately fitted with a polynomial regression model providing a measurement of upper airway critical pressure during twitch. This pressure significantly decreased in normals from expiratory to inspiratory twitches (-11.1 ± 1.6 and -15.7 ± 1.0 cm H2O respectively, 95% CI 1.6–7.6, p Conclusion Inspiratory-related upper airway dilating forces are impeded in sleep apnea patients.

  11. Anticholinergic treatment in airways diseases.

    LENUS (Irish Health Repository)

    Flynn, Robert A

    2009-10-01

    The prevalence of chronic airways diseases such as chronic obstructive pulmonary disease and asthma is increasing. They lead to symptoms such as a cough and shortness of breath, partially through bronchoconstriction. Inhaled anticholinergics are one of a number of treatments designed to treat bronchoconstriction in airways disease. Both short-acting and long-acting agents are now available and this review highlights their efficacy and adverse event profile in chronic airways diseases.

  12. Lung function, diagnosis, and treatment of sleep-disordered breathing in children with achondroplasia.

    Science.gov (United States)

    Julliand, Sébastien; Boulé, Michèle; Baujat, Geneviève; Ramirez, Adriana; Couloigner, Vincent; Beydon, Nicole; Zerah, Michel; di Rocco, Federico; Lemerrer, Martine; Cormier-Daire, Valérie; Fauroux, Brigitte

    2012-08-01

    Children with achondroplasia are at risk of sleep-disordered breathing. The aim of the study was to evaluate lung function and sleep-disordered breathing in children with achondroplasia. An interview, clinical examination, lung function tests with blood gases, and a polygraphic sleep study were obtained as part of routine annual evaluation in consecutive children with achondroplasia. We included 30 children (median age 3.0 years, range: 0.4-17.1) over a period of 21 months. Habitual snoring and witnessed apneas were observed in 77% and 33% of the patients, respectively. Prior to the sleep study, 10/29 (34%) patients had undergone upper airway surgery and 5/29 (17%) craniocervical decompression operation. Arterial blood gases were abnormal in two (7%) patients. Sleep findings were abnormal in 28/30 (93%) patients. Eleven (37%) patients had an apnea index≥1 event/hr and 26 (87%) had an apnea-hypopnea index≥5 events/hr. The ≥3% desaturation index was >5/hr in 22 (73%) patients. Sixteen (53%) patients had a minimal pulse oximetry50 mmHg during sleep. As a consequence, the following therapeutic interventions were performed: upper airway surgery in four patients and noninvasive positive pressure ventilation (NPPV) in five other patients, resulting in an improvement in sleep studies in all nine patients. Systematic sleep studies are recommended in children with achondroplasia because of the high prevalence of sleep-disordered breathing. Upper airway surgery and NPPV are effective treatments of sleep-disordered breathing. Copyright © 2012 Wiley Periodicals, Inc.

  13. Effect of nasal continuous and biphasic positive airway pressure on lung volume in preterm infants

    NARCIS (Netherlands)

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

    2013-01-01

    To monitor regional changes in end-expiratory lung volume (EELV), tidal volumes, and their ventilation distribution during different levels of nasal continuous positive airway pressure (nCPAP) and nasal biphasic positive airway pressure (BiPAP) in stable preterm infants. By using electrical

  14. Extubation success in premature infants with respiratory distress syndrome treated with bi-level nasal continuous positive airway pressure versus nasal intermittent positive pressure ventilation.

    Science.gov (United States)

    Thomas, Patricia E; LeFlore, Judy

    2013-01-01

    Infants born prematurely with respiratory distress syndrome are at high risk for complications from mechanical ventilation. Strategies are needed to minimize their days on the ventilator. The purpose of this study was to compare extubation success rates in infants treated with 2 different types of continuous positive airway pressure devices. A retrospective cohort study design was used. Data were retrieved from electronic medical records for patients in a large, metropolitan, level III neonatal intensive care unit. A sample of 194 premature infants with respiratory distress syndrome was selected, 124 of whom were treated with nasal intermittent positive pressure ventilation and 70 with bi-level variable flow nasal continuous positive airway pressure (bi-level nasal continuous positive airway pressure). Infants in both groups had high extubation success rates (79% of nasal intermittent positive pressure ventilation group and 77% of bi-level nasal continuous positive airway pressure group). Although infants in the bi-level nasal continuous positive airway pressure group were extubated sooner, there was no difference in duration of oxygen therapy between the 2 groups. Promoting early extubation and extubation success is a vital strategy to reduce complications of mechanical ventilation that adversely affect premature infants with respiratory distress syndrome.

  15. Bi-level positive airway pressure ventilation for treating heart failure with central sleep apnea that is unresponsive to continuous positive airway pressure.

    Science.gov (United States)

    Dohi, Tomotaka; Kasai, Takatoshi; Narui, Koji; Ishiwata, Sugao; Ohno, Minoru; Yamaguchi, Tetsu; Momomura, Shin-Ichi

    2008-07-01

    Cheyne-Stokes respiration with central sleep apnea (CSR-CSA) is associated with a poor prognosis in patients with heart failure (HF). However, some patients do not respond to continuous positive airway pressure (CPAP), so other therapeutic modalities should be considered, such as bi-level positive airway pressure (PAP), which also assists respiration and might be effective for such patients. The 20 patients with HF because of left ventricular systolic dysfunction were assessed: 8 had ischemic etiology, and all had severe CSA according to the apnea - hypopnea index (AHI) determined by polysomnography. All diagnosed patients underwent repeat polysomnography using CPAP. The AHI improved significantly in 11 (AHI or=15). Bi-level PAP titration significantly improved the AHI in the latter group. Those who were unresponsive to CPAP had significantly lower PaCO(2), higher plasma brain natriuretic peptide (BNP), longer mean duration of CSR and fewer obstructive episodes than CPAP responders. After 6 months of positive airway support with either CPAP (n=9) or bi-level PAP (n=7), BNP levels significantly decreased and left ventricular ejection fraction significantly increased. Bi-level PAP could be an effective alternative for patients with HF and pure CSR-CSA who are unresponsive to CPAP.

  16. Can a central blood volume deficit be detected by systolic pressure variation during spontaneous breathing?

    DEFF Research Database (Denmark)

    Dahl, Michael; Hayes, Chris; Steen Rasmussen, Bodil

    2016-01-01

    BACKGROUND: Whether during spontaneous breathing arterial pressure variations (APV) can detect a volume deficit is not established. We hypothesized that amplification of intra-thoracic pressure oscillations by breathing through resistors would enhance APV to allow identification of a reduced card...

  17. Duration of continuous positive airway pressure in premature infants

    OpenAIRE

    Bamat, Nicolas; Jensen, Erik A.; Kirpalani, Haresh

    2016-01-01

    Continuous positive airway pressure (CPAP) has been used for respiratory support in premature infants for more than 40 years and is now a cornerstone of modern neonatal care. Clinical research on CPAP has primarily focused on understanding which devices and pressure sources best implement this therapy. In contrast, less research has examined the optimal duration over which CPAP is administered. We review this aspect of CPAP therapy.

  18. Sleep apnea is associated with bronchial inflammation and continuous positive airway pressure-induced airway hyperresponsiveness.

    Science.gov (United States)

    Devouassoux, Gilles; Lévy, Patrick; Rossini, Eliane; Pin, Isabelle; Fior-Gozlan, Michèle; Henry, Mireille; Seigneurin, Daniel; Pépin, Jean-Louis

    2007-03-01

    Obstructive sleep apnea syndrome (OSA) is associated with systemic and upper airway inflammation. Pharyngeal inflammation has a potential role in upper airway collapse, whereas systemic inflammation relates to cardiovascular morbidity. However, the presence of an inflammatory involvement of lower airway has been poorly investigated. The aim of the study was to demonstrate an inflammatory process at the bronchial level in patients with OSA and to analyze effects of continuous positive airway pressure (CPAP) application and humidification on bronchial mucosa. The study was conducted by using sequential induced sputum for cell analysis and IL-8 production, nitric oxide exhalation measurement, and methacholine challenge before and after CPAP. Bronchial neutrophilia and a high IL-8 concentration were observed in untreated OSA compared with controls (75% +/- 20% vs 43% +/- 12%, P Obstructive sleep apnea syndrome is associated with bronchial inflammation. Our data demonstrate CPAP effect on the development of AHR, possibly facilitated by the pre-existing inflammation. Both issues should be evaluated during long-term CPAP use. Results showing a spontaneous bronchial inflammation in OSA and the development of a CPAP-related AHR require a long-term follow-up to evaluate consequences on chronic bronchial obstruction.

  19. Randomised Comparison of the AMBU AuraOnce Laryngeal Mask and the LMA Unique Laryngeal Mask Airway in Spontaneously Breathing Adults

    OpenAIRE

    Williams, Daryl Lindsay; Zeng, James M.; Alexander, Karl D.; Andrews, David T.

    2012-01-01

    We conducted a randomised single-blind controlled trial comparing the LMA-Unique (LMAU) and the AMBU AuraOnce (AMBU) disposable laryngeal mask in spontaneously breathing adult patients undergoing general anaesthesia. Eighty-two adult patients (ASA status I–IV) were randomly allocated to receive the LMAU or AMBU and were blinded to device selection. Patients received a standardized anesthetic and all airway devices were inserted by trained anaesthetists. Size selection was guided by manufactur...

  20. Sex differences in sleep disordered breathing in adults.

    Science.gov (United States)

    Lozo, Tijana; Komnenov, Dragana; Badr, M Safwan; Mateika, Jason H

    2017-11-01

    The prevalence of sleep disordered breathing is greater in men compared to women. This disparity could be due to sex differences in the diagnosis and presentation of sleep apnea, and the pathophysiological mechanisms that instigate this disorder. Women tend to report more non-typical symptoms of sleep apnea compared to men, and the presentation of apneic events are more prevalent in rapid compared to non-rapid eye movement sleep. In addition, there is evidence of sex differences in upper airway structure and mechanics and in neural mechanisms that impact on the control of breathing. The purpose of this review is to summarize the literature that addresses sex differences in sleep-disordered breathing, and to discuss the influence that upper airway mechanics, chemoreflex properties, and sex hormones have in modulating breathing during sleep in men and women. Published by Elsevier B.V.

  1. Absence of effect of nasal continuous positive airway pressure on the esophageal phase of nutritive swallowing in newborn lambs.

    Science.gov (United States)

    Djeddi, Djamal; Cantin, Danny; Samson, Nathalie; Tian, Hao; Praud, Jean-Paul

    2013-08-01

    It is presently recommended that oral feeding be started in premature infants as soon as possible, often at an age at which nasal continuous positive airway pressure (nCPAP) is still required for ventilatory support. Our previous data showed that application of nCPAP up to 10 cmH2O in full-term lambs had no deleterious effect on cardiorespiratory safety, feeding efficiency, or on nutritive swallowing-breathing coordination. Besides fear of swallowing-breathing coordination disturbances, esophageal motility disruption by nCPAP could be a reason to delay oral feeding. To our knowledge, no study has focused on the effects of nCPAP on esophageal motility in the neonatal period. The aim of the present study was therefore to further assess the effects of nCPAP on oral feeding by assessing its effects on the esophageal phase of nutritive swallowing (nutritive esophagodeglutition). Six full-term lambs, ages 2 to 3 days, underwent esophageal multichannel intraluminal impedance-pH monitoring. Lambs were bottle-fed under 2 randomized conditions, namely spontaneous breathing and nCPAP 6 cmH(2)O. Beyond confirmation of unaltered feeding efficiency, analysis of multiple variables measured by impedance monitoring revealed that nCPAP 6 does not alter nutritive esophagodeglutition in any way (nCPAP vs spontaneous breathing, P > 0.1 for all variables). offering further support to neonatologists pleading for initiation of oral feeding in infants still on nCPAP, the present results set the foundations for similar clinical studies in preterm human infants to confirm the absence of effects of nCPAP on nutritive swallowing.

  2. Duration of continuous positive airway pressure in premature infants

    Science.gov (United States)

    Bamat, Nicolas; Jensen, Erik A.; Kirpalani, Haresh

    2016-01-01

    SUMMARY Continuous positive airway pressure (CPAP) has been used for respiratory support in premature infants for more than 40 years and is now a cornerstone of modern neonatal care. Clinical research on CPAP has primarily focused on understanding which devices and pressure sources best implement this therapy. In contrast, less research has examined the optimal duration over which CPAP is administered. We review this aspect of CPAP therapy. PMID:26948885

  3. Mechanisms of breathing instability in patients with obstructive sleep apnea.

    Science.gov (United States)

    Younes, Magdy; Ostrowski, Michele; Atkar, Raj; Laprairie, John; Siemens, Andrea; Hanly, Patrick

    2007-12-01

    The response to chemical stimuli (chemical responsiveness) and the increases in respiratory drive required for arousal (arousal threshold) and for opening the airway without arousal (effective recruitment threshold) are important determinants of ventilatory instability and, hence, severity of obstructive apnea. We measured these variables in 21 obstructive apnea patients (apnea-hypopnea index 91 +/- 24 h(-1)) while on continuous-positive-airway pressure. During sleep, pressure was intermittently reduced (dial down) to induce severe hypopneas. Dial downs were done on room air and following approximately 30 s of breathing hypercapneic and/or hypoxic mixtures, which induced a range of ventilatory stimulation before dial down. Ventilation just before dial down and flow during dial down were measured. Chemical responsiveness, estimated as the percent increase in ventilation during the 5(th) breath following administration of 6% CO(2) combined with approximately 4% desaturation, was large (187 +/- 117%). Arousal threshold, estimated as the percent increase in ventilation associated with a 50% probability of arousal, ranged from 40% to >268% and was chemical drive. Effective recruitment threshold, estimated as percent increase in pre-dial-down ventilation associated with a significant increase in dial-down flow, ranged from zero to >174% and was chemical drive, but instability results because of a low arousal threshold and a brisk increase in drive following brief reduction in alveolar ventilation.

  4. Minimum concentrations of NO/sub 2/ causing acute effects on the respiratory gas exchange and airway-resistance in patients with chronic bronchitis

    Energy Technology Data Exchange (ETDEWEB)

    von Nieding, G; Wagner, M; Krekeler, H; Smidt, U; Muysers, K

    1971-01-01

    Nitrogen dioxide-air mixtures containing 0.5 to 5.0 ppM NO/sub 2/ were inhaled by 88 patients with chronic bronchitis over a 15-minute period for a total of 30 breaths during studies investigating the effects of the gas on airway resistance and respiratory gas exchange. End-expiratory oxygen pressures remained nearly constant during inhalation of 4 or 5 ppM NO/sub 2/, though significant decreases in arterial oxygen pressure accompanied by increases in end-expiratory-arterial oxygen pressure difference occurred. Inhalation of 2 ppM NO/sub 2/ did not decrease arterial oxygen pressure. Airway resistances increased significantly down to 1.5 ppM NO/sub 2/ concentrations. Lower concentrations caused no significant effects.

  5. Early nasal continuous positive airway pressure in a cohort of the smallest infants in Denmark

    DEFF Research Database (Denmark)

    Hansen, Bo M; Esbjørn, Barbara Hoff; Greisen, G

    2004-01-01

    To evaluate neurodevelopmental outcome at age 5 y of age in a cohort of preterm children treated mainly with nasal continuous positive airway pressure (CPAP) in the neonatal period.......To evaluate neurodevelopmental outcome at age 5 y of age in a cohort of preterm children treated mainly with nasal continuous positive airway pressure (CPAP) in the neonatal period....

  6. A pilot study to examine the effect of the Tulip oropharyngeal airway on ventilation immediately after mask ventilation following the induction of anaesthesia.

    Science.gov (United States)

    Robinson, P N; Shaikh, A; Sabir, N M; Vaughan, D J A; Kynoch, M; Hasan, M

    2014-07-01

    The Tulip airway is an adult, disposable, single-sized oropharyngeal airway, that is connectable to an anaesthetic circuit. After a standardised induction of anaesthesia in 75 patients, the ease of insertion, intracuff pressure and intracuff volume were measured, as were the end-tidal carbon dioxide levels, airway pressures and tidal volumes over three breaths. Successful first-time insertion was achieved in 72 patients (96%, CI 88.8-99.2%) and after two attempts in 74 patients (99%, CI 92.8-100%). There was outright failure only in one patient. In 60 patients (80%, CI 72.2-90.4%), the Tulip airway provided a patent airway without additional manoeuvres, but in 14 patients, jaw thrust or head extension was necessary for airway patency. The main need for these adjuncts appeared to be an initial under-inflation of the cuff. These promising results are consistent with recent manikin studies using this device. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

  7. Sleep-disordered breathing in epilepsy: epidemiology, mechanisms, and treatment.

    Science.gov (United States)

    Sivathamboo, Shobi; Perucca, Piero; Velakoulis, Dennis; Jones, Nigel C; Goldin, Jeremy; Kwan, Patrick; O'Brien, Terence J

    2018-04-01

    Epilepsy is a group of neurological conditions in which there is a pathological and enduring predisposition to generate recurrent seizures. Evidence over the last few decades suggests that epilepsy may be associated with increased sleep-disordered breathing, which may contribute towards sleep fragmentation, daytime somnolence, reduced seizure control, and cardiovascular-related morbidity and mortality. Chronic sleep-disordered breathing can result in loss of gray matter and cause deficits to memory and global cognitive function. Sleep-disordered breathing is a novel and independent predictor of sudden cardiac death and, as such, may be involved in the mechanisms leading to sudden unexpected death in epilepsy. Despite this, the long-term consequences of sleep-disordered breathing in epilepsy remain unknown, and there are no guidelines for screening or treating this population. There is currently insufficient evidence to indicate continuous positive airway pressure (CPAP) for the primary or secondary prevention of cardiovascular disease, and recent evidence has failed to show any reduction of fatal or nonfatal cardiovascular endpoints. Treatment of sleep-disordered breathing may potentially improve seizure control, daytime somnolence, and neurocognitive outcomes, but few studies have examined this relationship. In this review, we examine sleep-disordered breathing in epilepsy, and discuss the potential effect of epilepsy treatments. We consider the role of CPAP and other interventions for sleep-disordered breathing and discuss their implications for epilepsy management.

  8. Nasal bi-level positive airway pressure (BiPAP) versus nasal continuous positive airway pressure (CPAP) in preterm infants ≤32 weeks: A retrospective cohort study.

    Science.gov (United States)

    Rong, Zhi-Hui; Li, Wen-Bin; Liu, Wei; Cai, Bao-Huan; Wang, Jing; Yang, Min; Li, Wei; Chang, Li-Wen

    2016-05-01

    To investigate whether Bi-level positive airway pressure (BiPAP), compared with nasal continuous positive airway pressure (CPAP), is a more effective therapeutic strategy in preterm infants ≤32 weeks. All inborn infants between 26(+1) and 32(+6) weeks' gestation, admitted to the neonatal intensive care unit (NICU ) of Tongji Medical Hospital between 1 January, 2010 and 31 December, 2011 (the 2010-2011 cohort or CPAP cohort) and between 1 January, 2012 and 31 December, 2013 (the 2012-2013 cohort or BiPAP cohort), were retrospectively identified. The primary outcome was intubation in infants CPAP were subsequently intubated (P CPAP, reduced the need for intubation within the first 72 h of age. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  9. Plethysmographic measurements of specific airway resistance in young children

    DEFF Research Database (Denmark)

    Bisgaard, Hans; Nielsen, Kim G

    2005-01-01

    allowed discrimination of young children with respiratory disease. Bronchial hyperresponsiveness can be determined with acceptable short-term and long-term repeatability and provides good discrimination between asthmatics and healthy young children. The effects of the major antiasthmatic therapies have......Validated methods for lung function measurements in young children are lacking. Plethysmographic measurement of specific airway resistance (sRaw) provides such a method applicable from 2 years of age. sRaw gauges airway resistance from the measurements of the pressure changes driving the airflow...... during tidal breathing. These measurements require no active cooperation and are therefore feasible in children from 2 years of age. The within-observer and between-observer variability of sRaw in young children compare favorably with alternative methods. Reference values are available for sRaw and have...

  10. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... many challenges, including medical, social, and financial. By learning more about how you can manage your disease every day, you can ultimately help find a ... Cycle of Breathing Technique Airway Clearance Techniques Autogenic ...

  11. Comparison of airway pressure release ventilation to conventional mechanical ventilation in the early management of smoke inhalation injury in swine.

    Science.gov (United States)

    Batchinsky, Andriy I; Burkett, Samuel E; Zanders, Thomas B; Chung, Kevin K; Regn, Dara D; Jordan, Bryan S; Necsoiu, Corina; Nguyen, Ruth; Hanson, Margaret A; Morris, Michael J; Cancio, Leopoldo C

    2011-10-01

    The role of airway pressure release ventilation in the management of early smoke inhalation injury has not been studied. We compared the effects of airway pressure release ventilation and conventional mechanical ventilation on oxygenation in a porcine model of acute respiratory distress syndrome induced by wood smoke inhalation. Prospective animal study. Government laboratory animal intensive care unit. Thirty-three Yorkshire pigs. Smoke inhalation injury. Anesthetized female Yorkshire pigs (n = 33) inhaled room-temperature pine-bark smoke. Before injury, the pigs were randomized to receive conventional mechanical ventilation (n = 15) or airway pressure release ventilation (n = 12) for 48 hrs after smoke inhalation. As acute respiratory distress syndrome developed (PaO2/Fio2 ratio 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 hemodynamic variables were recorded. Survival was assessed using Kaplan-Meier analysis. PaO2/Fio2 ratio was lower in airway pressure release ventilation vs. conventional mechanical ventilation pigs at 12, 18, and 24 hrs (p conventional mechanical ventilation animals between 30 and 48 hrs post injury (p animals between 6 and 48 hrs (p conventional mechanical ventilation and airway pressure release ventilation pigs. In this model of acute respiratory distress syndrome caused by severe smoke inhalation in swine, airway pressure release ventilation-treated animals developed acute respiratory distress syndrome faster than conventional mechanical ventilation-treated animals, showing a lower PaO2/Fio2 ratio at 12, 18, and 24 hrs after injury. At other time points, PaO2/Fio2 ratio was not different between conventional mechanical ventilation and airway pressure release ventilation.

  12. Deep breathing exercises with positive expiratory pressure in patients with multiple sclerosis - a randomized controlled trial.

    Science.gov (United States)

    Westerdahl, Elisabeth; Wittrin, Anna; Kånåhols, Margareta; Gunnarsson, Martin; Nilsagård, Ylva

    2016-11-01

    Breathing exercises with positive expiratory pressure are often recommended to patients with advanced neurological deficits, but the potential benefit in multiple sclerosis (MS) patients with mild and moderate symptoms has not yet been investigated in randomized controlled trials. To study the effects of 2 months of home-based breathing exercises for patients with mild to moderate MS on respiratory muscle strength, lung function, and subjective breathing and health status outcomes. Forty-eight patients with MS according to the revised McDonald criteria were enrolled in a randomized controlled trial. Patients performing breathing exercises (n = 23) were compared with a control group (n = 25) performing no breathing exercises. The breathing exercises were performed with a positive expiratory pressure device (10-15 cmH 2 O) and consisted of 30 slow deep breaths performed twice a day for 2 months. Respiratory muscle strength (maximal inspiratory and expiratory pressure at the mouth), spirometry, oxygenation, thoracic excursion, subjective perceptions of breathing and self-reported health status were evaluated before and after the intervention period. Following the intervention, there was a significant difference between the breathing group and the control group regarding the relative change in lung function, favoring the breathing group (vital capacity: P < 0.043; forced vital capacity: P < 0.025). There were no other significant differences between the groups. Breathing exercises may be beneficial in patients with mild to moderate stages of MS. However, the clinical significance needs to be clarified, and it remains to be seen whether a sustainable effect in delaying the development of respiratory dysfunction in MS can be obtained. © 2015 The Authors. The Clinical Respiratory Journal published by John Wiley & Sons Ltd.

  13. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... decisions about your health care. CF Genetics: The Basics CF Mutations Video Series Find Out More About ... of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy Coughing and ...

  14. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... a Family Parenting as an Adult With CF Treatments and Therapies People with cystic fibrosis are living ... to specialized CF care and a range of treatment options. Airway Clearance Active Cycle of Breathing Technique ...

  15. Variability of breath condensate pH may contribute to the better understanding of non-allergic seasonal respiratory diseases

    Science.gov (United States)

    Kullmann, Tamás; Szipőcs, Annamária

    2017-09-01

    The seasonal variability of certain non-allergic respiratory diseases is not clearly understood. Analysis of the breath condensate, the liquid that can be collected by breathing into a cold tube, has been proposed to bring closer to the understanding of airway pathologies. It has been assumed, that (1) airway lining fluid was a stable body liquid and (2) the breath condensate samples were representative of the airway lining fluid. Research was focussed on the identification of biomarkers indicative of respiratory pathologies. Despite 30 years of extended investigations breath condensate analysis has not gained any clinical implementation so far. The pH of the condensate is the characteristic that can be determined with the highest reproducibility. The present paper shows, that contrary to the initial assumptions, breath condensate is not a representative of the airway lining fluid, and the airway lining fluid is not a stable body liquid. Condensate pH shows baseline variability and it is influenced by drinking and by the ambient temperature. The changes in condensate pH are linked to changes in airway lining fluid pH. The variability of airway lining fluid pH may explain seasonal incidence of certain non-allergic respiratory diseases such as the catching of a common cold and the increased incidence of COPD exacerbations and exercise-induced bronchoconstriction in cold periods.

  16. Imaging of mucus clearance in the airways of living spontaneously breathing mice by optical coherence microscopy (Conference Presentation)

    Science.gov (United States)

    Pieper, Mario; Schulz-Hildebrandt, Hinnerk; Hüttmann, Gereon; König, Peter

    2016-03-01

    Mucus transport is essential to remove inhaled particles and pathogens from the lung. Impaired removal of mucus often results in worsening of lung diseases. To understand the mechanisms of mucus transport and to monitor the impact of therapeutic strategies, it is essential to visualize airways and mucus in living animals without disturbing transport processes by intubation or surgically opening the airways. We developed a custom-built optical coherence microscope (OCM) providing a lateral and axial resolution of approximately 1.5 µm with a field of view of 2 mm at up to 150 images/s. Images of the intact trachea and its mucus transport were recorded in anesthetized spontaneously breathing mice. NaCl solution (0.9% and 7%) or Lipopolysaccharide were applied intranasally. OCM resolved detailed structure of the trachea and enabled measuring the airway surface liquid (ASL) thickness through the tracheal wall. Without stimulation, the amount of ASL was only a few µm above the epithelium and remained constant. After intranasal application of 30 µl saline at different concentrations, an early fast cough-like fluid removal with velocities higher than 1 mm/s was observed that removed a high amount of liquid. The ASL thickness increased transiently and quickly returned to levels before stimulation. In contrast to saline, application of Lipopolysaccharide induced substantial mucus release and an additional slow mucus transport by ciliary beating (around 100 µm/s) towards the larynx was observed. In conclusion, OCM is appropriate unique tool to study mechanisms of mucus transport in the airways and effects of therapeutic interventions in living animals.

  17. Improved fireman's compressed air breathing system pressure vessel development program

    Science.gov (United States)

    King, H. A.; Morris, E. E.

    1973-01-01

    Prototype high pressure glass filament-wound, aluminum-lined pressurant vessels suitable for use in a fireman's compressed air breathing system were designed, fabricated, and acceptance tested in order to demonstrate the feasibility of producing such high performance, lightweight units. The 4000 psi tanks have a 60 standard cubic foot (SCF) air capacity, and have a 6.5 inch diamter, 19 inch length, 415 inch volume, weigh 13 pounds when empty, and contain 33 percent more air than the current 45 SCF (2250 psi) steel units. The current steel 60 SCF (3000 psi) tanks weigh approximately twice as much as the prototype when empty, and are 2 inches, or 10 percent shorter. The prototype units also have non-rusting aluminum interiors, which removes the hazard of corrosion, the need for internal coatings, and the possibility of rust particles clogging the breathing system.

  18. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... a Family Parenting as an Adult With CF Treatments and Therapies People with cystic fibrosis are living longer and ... to specialized CF care and a range of treatment options. Airway Clearance Active Cycle of Breathing Technique ...

  19. New frontiers in CT imaging of airway disease

    International Nuclear Information System (INIS)

    Grenier, Philippe A.; Beigelman-Aubry, Catherine; Fetita, Catalin; Preteux, Francoise; Brauner, Michel W.; Lenoir, Stephane

    2002-01-01

    Combining helical volumetric CT acquisition and thin-slice thickness during breath hold provides an accurate assessment of both focal and diffuse airway diseases. With multiple detector rows, compared with single-slice helical CT, multislice CT can cover a greater volume, during a simple breath hold, and with better longitudinal and in-plane spatial resolution and improved temporal resolution. The result in data set allows the generation of superior multiplanar and 3D images of the airways, including those obtained from techniques developed specifically for airway imaging, such as virtual bronchography and virtual bronchoscopy. Complementary CT evaluation at suspended or continuous full expiration is mandatory to detect air trapping that is a key finding for depicting an obstruction on the small airways. Indications for CT evaluation of the airways include: (a) detection of endobronchial lesions in patients with an unexplained hemoptysis; (b) evaluation of extent of tracheobronchial stenosis for planning treatment and follow-up; (c) detection of congenital airway anomalies revealed by hemoptysis or recurrent infection; (d) detection of postinfectious or postoperative airway fistula or dehiscence; and (e) diagnosis and assessment of extent of bronchiectasis and small airway disease. Improvement in image analysis technique and the use of spirometrically control of lung volume acquisition have made possible accurate and reproducible quantitative assessment of airway wall and lumen areas and lung density. This contributes to better insights in physiopathology of obstructive lung disease, particularly in chronic obstructive pulmonary disease and asthma. (orig.)

  20. Influence of mouth opening on oropharyngeal humidification and temperature in a bench model of neonatal continuous positive airway pressure.

    Science.gov (United States)

    Fischer, Hendrik S; Ullrich, Tim L; Bührer, Christoph; Czernik, Christoph; Schmalisch, Gerd

    2017-02-01

    Clinical studies show that non-invasive respiratory support by continuous positive airway pressure (CPAP) affects gas conditioning in the upper airways, especially in the presence of mouth leaks. Using a new bench model of neonatal CPAP, we investigated the influence of mouth opening on oropharyngeal temperature and humidity. The model features the insertion of a heated humidifier between an active model lung and an oropharyngeal head model to simulate the recurrent expiration of heated, humidified air. During unsupported breathing, physiological temperature and humidity were attained inside the model oropharynx, and mouth opening had no significant effect on oropharyngeal temperature and humidity. During binasal CPAP, the impact of mouth opening was investigated using three different scenarios: no conditioning in the CPAP circuit, heating only, and heated humidification. Mouth opening had a strong negative impact on oropharyngeal humidification in all tested scenarios, but heated humidification in the CPAP circuit maintained clinically acceptable humidity levels regardless of closed or open mouths. The model can be used to test new equipment for use with CPAP, and to investigate the effects of other methods of non-invasive respiratory support on gas conditioning in the presence of leaks. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Nasal continuous positive airway pressure

    DEFF Research Database (Denmark)

    Scholze, Alexandra; Lamwers, Stephanie; Tepel, Martin

    2012-01-01

    Obstructive sleep apnoea (OSA) is linked to increased cardiovascular risk. This risk can be reduced by nasal continuous positive airway pressure (nCPAP) treatment. As OSA is associated with an increase of several vasoconstrictive factors, we investigated whether nCPAP influences the digital volume...... pulse wave. We performed digital photoplethysmography during sleep at night in 94 consecutive patients who underwent polysomnography and 29 patients treated with nCPAP. Digital volume pulse waves were obtained independently of an investigator and were quantified using an algorithm for continuous.......01; n = 94) and the arousal index (Spearman correlation, r = 0.21; p CPAP treatment, the AHI was significantly reduced from 27 ± 3 events · h(-1) to 4 ± 2 events · h(-1) (each n = 29; p

  2. Boussignac continuous positive airway pressure for weaning with tracheostomy tubes

    NARCIS (Netherlands)

    Dieperink, Willem; Aarts, Leon P. H. J.; Rodgers, Michael G. G.; Delwig, Hans; Nijsten, Maarten W. N.

    2008-01-01

    Background: In patients who are weaned with a tracheostomy tube ( TT), continuous positive airway pressure ( CPAP) is frequently used. Dedicated CPAP systems or ventilators with bulky tubing are usually applied. However, CPAP can also be effective without a ventilator by the disposable Bous-signac

  3. Impact of Polysomnographic Parameters on Continuous Positive Airway Pressure in Patient with Obstructive Sleep Apnea in 2012

    Directory of Open Access Journals (Sweden)

    Abolfazl Mozafari

    2014-06-01

    Full Text Available Background & objectives : O bstructive sleep apnea is a preventable and prevalent major health hazard with serious health consequences including excessive daytime sleepiness, cognitive disturbances, depression, cardiovascular diseases and hypertension. Obstructive sleep apnea is a disorder affecting 2 to 4% of the adult population. The continuous positive airway pressur e (CPAP i s the most efficacious therapy and is often the first option for these patients. The pressure titration during laboratory polysomnography is required for treatment by CPAP.   Methods: The patients with obstructive sleep apnea requiring continuous positive airway pressure treatment were selected . CPAP titration was done according to American Academy of Sleep Medicine protocol. Comparison among continuous positive airway pressure with polysomnographic parameters was performed and analyzed with Pearson correlation coefficient. For analysis of qualitative parameters, we used chi-square and then checked with SPSS version 18 software.   Results: From 125 patients with obstructive sleep apnea, there were 112 cases with inclusion criteria. Mean age of participants was 55.07 ± 12, male frequency was 59.2%, apnea hypopnea index was 43.62 and mean continuous positive airway pressure was 12.50 . There was significant relationship among the pressure of continuous positive airway pressure with apnea hypopnea index (P=0.028, arousal index (P=0.011, body mass index (P=0.041 and O2 desaturation index (P=0.022, although age was not significantly related.   Conclusion: In accordance to this data, we found out a prediction equation for optimal CPAP in our patients

  4. Orofacial-cervical alterations in individuals with upper airway resistance syndrome

    Directory of Open Access Journals (Sweden)

    Pedro Wey Barbosa de Oliveira

    Full Text Available ABSTRACT INTRODUCTION: Studies that assess the upper airways in sleep-related breathing disorders have been performed only in patients with obstructive sleep apnea syndrome who seek medical attention. Therefore, in addition to the need for population studies, there are no data on the orofacial-cervical physical examination in subjects with upper airway resistance syndrome. OBJECTIVES: To compare the orofacial-cervical examination between volunteers with upper airway resistance syndrome and without sleep-related breathing disorders. METHODS: Through questionnaires, physical measurements, polysomnography, and otorhinolaryngological evaluation, this study compared the orofacial-cervical physical examination, through a systematic analysis of the facial skeleton, mouth, throat, and nose, between volunteers with upper airway resistance syndrome and volunteers without sleep-related breathing disorders in a representative sample of the adult population of the city of São Paulo. RESULTS: There were 1042 volunteers evaluated; 49 subjects (5% were excluded as they did not undergo otorhinolaryngological evaluation, 381 (36% had apnea-hypopnea index > 5 events/hour, and 131 (13% had oxyhemoglobin saturation < 90%. Among the remaining 481 subjects (46%, 30 (3% met the criteria for the upper airway resistance syndrome definition and 53 (5% met the control group criteria. At the clinical evaluation of nasal symptoms, the upper airway resistance syndrome group had more oropharyngeal dryness (17% vs. 29.6%; p = 0.025 and septal deviation grades 1-3 (49.1% vs. 57.7%; p = 0.025 when compared to controls. In the logistic regression model, it was found that individuals from the upper airway resistance syndrome group had 15.6-fold higher chance of having nose alterations, 11.2-fold higher chance of being hypertensive, and 7.6-fold higher chance of complaining of oropharyngeal dryness when compared to the control group. CONCLUSION: Systematic evaluation of the facial

  5. Effect of different levels of continuous positive airway pressure on the 99mTc-DTPA lung clearance

    Directory of Open Access Journals (Sweden)

    Dulciane Nunes Paiva

    2014-04-01

    Full Text Available Backgound and Objectives: Positive airway pressure continues (CPAP produces significant hemodynamic changes that may influence the variability of breathing pattern and heart rate, acting as an additional therapy to prevent atelectasis and to combat hypoxia. The rate of inhaled 99 m Technetiumdiethylenetriaminepentaacetic acid (99mTc-DTPA, along with changes in the lung epithelium cause an increase in the rate of clearance of this compound. The aim of this study was evaluate the pulmonary clearance rate of 99mTechnetium Diethylenetriaminepentaacetic acid (99mTc-DTPA through the use of different levels of CPAP. Methods: It was a quasi-experimental study involving 17 healthy individuals with normal lung functional. 99mTc-DTPA, as aerosol, was nebulized for 3 minutes with the individual in a sitting position. The pulmonary clearance rate was assessed through pulmonary scintigraphy under spontaneous breathing and under 20 and 10 cmH2 O CPAP in the sitting position. The clearance rate was expressed as the half-time (T½ that is the time for the activity to decrease to 50% of the peak value. Results: 20 cmH2 O CPAP produced significant reduction of the T½ of 99mTc-DTPA in the sitting position (p=0.005. However, 10 cmH2 O CPAP did not alter the T½ of DTPA in the same positions. Conclusion: High levels of continuos positive pressure in normal lungs resulted in faster 99mTc-DTPA clearance moreover, 10 cmH2 O did not alter its clearance rate. KEYWORDS: Noninvasive ventilation. Technetium Tc 99m Pentetate. Radionuclide Imaging.

  6. Lung sound analysis helps localize airway inflammation in patients with bronchial asthma

    Directory of Open Access Journals (Sweden)

    Shimoda T

    2017-03-01

    Full Text Available Terufumi Shimoda,1 Yasushi Obase,2 Yukio Nagasaka,3 Hiroshi Nakano,1 Akiko Ishimatsu,1 Reiko Kishikawa,1 Tomoaki Iwanaga1 1Clinical Research Center, Fukuoka National Hospital, Fukuoka, 2Second Department of Internal Medicine, School of Medicine, Nagasaki University, Nagasaki, 3Kyoto Respiratory Center, Otowa Hospital, Kyoto, Japan Purpose: Airway inflammation can be detected by lung sound analysis (LSA at a single point in the posterior lower lung field. We performed LSA at 7 points to examine whether the technique could identify the location of airway inflammation in patients with asthma. Patients and methods: Breath sounds were recorded at 7 points on the body surface of 22 asthmatic subjects. Inspiration sound pressure level (ISPL, expiration sound pressure level (ESPL, and the expiration-to-inspiration sound pressure ratio (E/I were calculated in 6 frequency bands. The data were analyzed for potential correlation with spirometry, airway hyperresponsiveness (PC20, and fractional exhaled nitric oxide (FeNO. Results: The E/I data in the frequency range of 100–400 Hz (E/I low frequency [LF], E/I mid frequency [MF] were better correlated with the spirometry, PC20, and FeNO values than were the ISPL or ESPL data. The left anterior chest and left posterior lower recording positions were associated with the best correlations (forced expiratory volume in 1 second/forced vital capacity: r=–0.55 and r=–0.58; logPC20: r=–0.46 and r=–0.45; and FeNO: r=0.42 and r=0.46, respectively. The majority of asthmatic subjects with FeNO ≥70 ppb exhibited high E/I MF levels in all lung fields (excluding the trachea and V50%pred <80%, suggesting inflammation throughout the airway. Asthmatic subjects with FeNO <70 ppb showed high or low E/I MF levels depending on the recording position, indicating uneven airway inflammation. Conclusion: E/I LF and E/I MF are more useful LSA parameters for evaluating airway inflammation in bronchial asthma; 7-point lung

  7. Multiple applications of the Boussignac continuous positive airway pressure system

    NARCIS (Netherlands)

    Dieperink, Willem

    2008-01-01

    Continuous positive airway pressure, (CPAP) is a form of treatment to support patients with dyspnea. For the application of CPAP a mechanical ventilator or complex CPAP apparatus is mostly used. The Boussignac CPAP (BCPAP) system developed by George Boussignac does not need such apparatus. The BCPAP

  8. The contribution of airway smooth muscle to airway narrowing and airway hyperresponsiveness in disease.

    Science.gov (United States)

    Martin, J G; Duguet, A; Eidelman, D H

    2000-08-01

    Airway hyperresponsiveness (AHR), the exaggerated response to constrictor agonists in asthmatic subjects, is incompletely understood. Changes in either the quantity or properties of airway smooth muscle (ASM) are possible explanations for AHR. Morphometric analyses demonstrate structural changes in asthmatic airways, including subepithelial fibrosis, gland hyperplasia/hypertrophy, neovascularization and an increase in ASM mass. Mathematical modelling of airway narrowing suggests that, of all the changes in structure, the increase in ASM mass is the most probable cause of AHR. An increase in ASM mass in the large airways is more closely associated with a greater likelihood of dying from asthma than increases in ASM mass in other locations within the airway tree. ASM contraction is opposed by the elastic recoil of the lungs and airways, which appears to limit the degree of bronchoconstriction in vivo. The cyclical nature of tidal breathing applies stresses to the airway wall that enhance the bronchodilating influence of the lung tissues on the contracting ASM, in all probability by disrupting cross-bridges. However, the increase in ASM mass in asthma may overcome the limitation resulting from the impedances to ASM shortening imposed by the lung parenchyma and airway wall tissues. Additionally, ASM with the capacity to shorten rapidly may achieve shorter lengths and cause a greater degree of bronchoconstriction when stimulated to contract than slower ASM. Changes in ASM properties are induced by the process of sensitization and allergen-exposure such as enhancement of phospholipase C activity and inositol phosphate turnover, and increases in myosin light chain kinase activity. Whether changes in ASM mass or biochemical/biomechanical properties form the basis for asthma remains to be determined.

  9. Firefighter's compressed air breathing system pressure vessel development program

    Science.gov (United States)

    Beck, E. J.

    1974-01-01

    The research to design, fabricate, test, and deliver a pressure vessel for the main component in an improved high-performance firefighter's breathing system is reported. The principal physical and performance characteristics of the vessel which were required are: (1) maximum weight of 9.0 lb; (2) maximum operating pressure of 4500 psig (charge pressure of 4000 psig); (3) minimum contained volume of 280 in. 3; (4) proof pressure of 6750 psig; (5) minimum burst pressure of 9000 psig following operational and service life; and (6) a minimum service life of 15 years. The vessel developed to fulfill the requirements described was completely sucessful, i.e., every category of performence was satisfied. The average weight of the vessel was found to be about 8.3 lb, well below the 9.0 lb specification requirement.

  10. Positive airway pressure adherence and subthreshold adherence in posttraumatic stress disorder patients with comorbid sleep apnea

    Directory of Open Access Journals (Sweden)

    Krakow BJ

    2017-11-01

    Full Text Available Barry J Krakow,1–3 Jessica J Obando,2 Victor A Ulibarri,1,2 Natalia D McIver1,2 1Sleep & Human Health Institute, 2Maimonides Sleep Arts & Sciences, Albuquerque, 3Los Alamos Medical Center, Los Alamos, NM, USA Study objectives: Patients with comorbid posttraumatic stress disorder (PTSD and obstructive sleep apnea (OSA manifest low adherence to continuous positive airway pressure (CPAP due to fixed, pressure-induced expiratory pressure intolerance (EPI, a subjective symptom and objective sign aggravated by anxiety sensitivity and somatosensory amplification. As advanced PAP therapy modes (ie, auto-bilevel PAP [ABPAP] or adaptive servo-ventilation [ASV] may address these side effects, we hypothesized such treatment would be associated with decreased expiratory intolerance and increased adherence in posttraumatic stress patients with co-occurring OSA.Methods: We reviewed charts of 147 consecutive adult patients with moderately severe posttraumatic stress symptoms and objectively diagnosed OSA. All patients failed or rejected CPAP and were manually titrated on auto-adjusting, dual-pressure ABPAP or ASV modes in the sleep laboratory, a technique to eliminate flow limitation breathing events while resolving EPI. Patients were then prescribed either mode of therapy. Follow-up encounters assessed patient use, and objective data downloads (ODDs measured adherence.Results: Of 147 charts reviewed, 130 patients were deemed current PAP users, and 102 provided ODDs: 64 used ASV and 38 used ABPAP. ODDs yielded three groups: 59 adherent per insurance conventions, 19 subthreshold compliant partial users, and 24 noncompliant. Compliance based on available downloads was 58%, notably higher than recently reported rates in PTSD patients with OSA. Among the 19 partial users, 17 patients were minutes of PAP use or small percentages of nights removed from meeting insurance compliance criteria for PAP devices.Conclusion: Research is warranted on advanced PAP modes in

  11. Nap-titration : An effective alternative for continuous positive airway pressure titration

    NARCIS (Netherlands)

    Hoekema, A; Stegenga, B; Meinesz, AF; van der Hoeven, JH; Wijkstra, PJ

    When treating Obstructive Steep Apnea-Hypopnea Syndrome (OSAHS) several alternatives for standard (manual) continuous positive airway pressure (CPAP) titration are feasible. A practical alternative is titration without polysomnography during an afternoon nap (Nap-titration). The aim of the present

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

    Science.gov (United States)

    Finucane, Kevin E; Singh, Bhajan

    2018-01-01

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

  13. Breath acidification in adolescent runners exposed to atmospheric pollution: A prospective, repeated measures observational study

    Directory of Open Access Journals (Sweden)

    Van Sickle David

    2008-03-01

    Full Text Available Abstract Background Vigorous outdoors exercise during an episode of air pollution might cause airway inflammation. The purpose of this study was to examine the effects of vigorous outdoor exercise during peak smog season on breath pH, a biomarker of airway inflammation, in adolescent athletes. Methods We measured breath pH both pre- and post-exercise on ten days during peak smog season in 16 high school athletes engaged in daily long-distance running in a downwind suburb of Atlanta. The association of post-exercise breath pH with ambient ozone and particulate matter concentrations was tested with linear regression. Results We collected 144 pre-exercise and 146 post-exercise breath samples from 16 runners (mean age 14.9 years, 56% male. Median pre-exercise breath pH was 7.58 (interquartile range: 6.90 to 7.86 and did not change significantly after exercise. We observed no significant association between ambient ozone or particulate matter and post-exercise breath pH. However both pre- and post-exercise breath pH were strikingly low in these athletes when compared to a control sample of 14 relatively sedentary healthy adults and to published values of breath pH in healthy subjects. Conclusion Although we did not observe an acute effect of air pollution exposure during exercise on breath pH, breath pH was surprisingly low in this sample of otherwise healthy long-distance runners. We speculate that repetitive vigorous exercise may induce airway acidification.

  14. Efficacy of the addition of positive airway pressure to conventional chest physiotherapy in resolution of pleural effusion after drainage: protocol for a randomised controlled trial.

    Science.gov (United States)

    da Conceição Dos Santos, Elinaldo; Lunardi, Adriana Claudia

    2015-04-01

    Chest drainage for pleural effusion can cause pain and changes in respiratory function. It can also increase the risk of pulmonary complications and impair functional ability, which may increase length of hospital stay and the associated costs. For these reasons, surgical and clinical strategies have been adopted to reduce the duration of chest drainage. To evaluate the efficacy of the addition of intermittent positive airway pressure applied by the Muller reanimator via a rubber facial mask versus conventional physiotherapy on the duration of chest drainage (primary objective), and its effect on the recovery of respiratory function, length of hospital stay and incidence of pulmonary complications (secondary objectives). Randomised, controlled trial. Inpatients with pleural effusion, aged over 18 years, who have had chest drainage in situ for drain will be a transudate output ≤ 200ml over 24hours and full lung expansion on chest radiography, as assessed by a blinded physician. Duration of chest drainage, length of hospital stay, and any pulmonary complications diagnosed during hospitalisation will be recorded. Intention to treat using: survival analysis for duration of chest drainage, and length of hospital stay; analysis of variance for chest-tube output, lung function and peripheral oxygen saturation; and chi-square tests for comparing the incidence of pulmonary complications between groups. Conventional chest physiotherapy and intermittent positive airway pressure breathing are widely indicated for people with pleural effusion and chest drains; however, no studies have evaluated the real benefit of this type of treatment. Our hypothesis is that optimised lung expansion achieved through the application of intermittent positive airway pressure will accelerate the reabsorption of pleural effusion, decrease the duration of chest drainage and respiratory system impairment, reduce the length of hospital stay, and reduce the incidence of pulmonary complications

  15. Nasal continuous positive airway pressure: does bubbling improve gas exchange?

    Science.gov (United States)

    Morley, C J; Lau, R; De Paoli, A; Davis, P G

    2005-07-01

    In a randomised crossover trial, 26 babies, treated with Hudson prong continuous positive airway pressure (CPAP) from a bubbling bottle, received vigorous, high amplitude, or slow bubbling for 30 minutes. Pulse oximetry, transcutaneous carbon dioxide, and respiratory rate were recorded. The bubbling rates had no effect on carbon dioxide, oxygenation, or respiratory rate.

  16. Pressure Dependence of the Radial Breathing Mode of Carbon Nanotubes: The Effect of Fluid Adsorption

    Science.gov (United States)

    Longhurst, M. J.; Quirke, N.

    2007-04-01

    The pressure dependence of shifts in the vibrational modes of individual carbon nanotubes is strongly affected by the nature of the pressure transmitting medium as a result of adsorption at the nanotube surface. The adsorbate is treated as an elastic shell which couples with the radial breathing mode (RBM) of the nanotube via van der Waal interactions. Using analytical methods as well as molecular simulation, we observe a low frequency breathing mode for the adsorbed fluid at ˜50cm-1, as well as diameter dependent upshifts in the RBM frequency with pressure, suggesting metallic nanotubes may wet more than semiconducting ones.

  17. Effect of different breathing aids on ventilation distribution in adults with cystic fibrosis.

    Directory of Open Access Journals (Sweden)

    Markus Wettstein

    Full Text Available BACKGROUND AND OBJECTIVES: We investigated the effect of different breathing aids on ventilation distribution in healthy adults and subjects with cystic fibrosis (CF. METHODS: In 11 healthy adults and 9 adults with CF electrical impedance tomography measurements were performed during spontaneous breathing, continuous positive airway pressure (CPAP and positive expiratory pressure (PEP therapy randomly applied in upright and lateral position. Spatial and temporal ventilation distribution was assessed. RESULTS: The proportion of ventilation directed to the dependent lung significantly increased in lateral position compared to upright in healthy and CF. This effect was enhanced with CPAP but neutralised with PEP, whereas the effect of PEP was larger in the healthy group. Temporal ventilation distribution showed exactly the opposite with homogenisation during CPAP and increased inhomogeneity with PEP. CONCLUSIONS: PEP shows distinct differences to CPAP with respect to its impact on ventilation distribution in healthy adults and CF subjects EIT might be used to individualise respiratory physiotherapy.

  18. Comparison of Ambient and Atmospheric Pressure Ion Sources for Cystic Fibrosis Exhaled Breath Condensate Ion Mobility-Mass Spectrometry Metabolomics

    Science.gov (United States)

    Zang, Xiaoling; Pérez, José J.; Jones, Christina M.; Monge, María Eugenia; McCarty, Nael A.; Stecenko, Arlene A.; Fernández, Facundo M.

    2017-08-01

    Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the gene that encodes the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The vast majority of the mortality is due to progressive lung disease. Targeted and untargeted CF breath metabolomics investigations via exhaled breath condensate (EBC) analyses have the potential to expose metabolic alterations associated with CF pathology and aid in assessing the effectiveness of CF therapies. Here, transmission-mode direct analysis in real time traveling wave ion mobility spectrometry time-of-flight mass spectrometry (TM-DART-TWIMS-TOF MS) was tested as a high-throughput alternative to conventional direct infusion (DI) electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) methods, and a critical comparison of the three ionization methods was conducted. EBC was chosen as the noninvasive surrogate for airway sampling over expectorated sputum as EBC can be collected in all CF subjects regardless of age and lung disease severity. When using pooled EBC collected from a healthy control, ESI detected the most metabolites, APCI a log order less, and TM-DART the least. TM-DART-TWIMS-TOF MS was used to profile metabolites in EBC samples from five healthy controls and four CF patients, finding that a panel of three discriminant EBC metabolites, some of which had been previously detected by other methods, differentiated these two classes with excellent cross-validated accuracy.

  19. Small airways dysfunction and neutrophilic inflammation in bronchial biopsies and BAL in COPD

    NARCIS (Netherlands)

    Lapperre, Thérèse S.; Willems, Luuk N. A.; Timens, Wim; Rabe, Klaus F.; Hiemstra, Pieter S.; Postma, Dirkje S.; Sterk, Peter J.

    2007-01-01

    BACKGROUND: The single-breath N(2) test (sbN(2)-test) is closely related to small airways pathology in resected lung specimens of smokers. We investigated whether uneven ventilation and airway closure are associated with specific markers of airway inflammation as obtained by bronchial biopsies, BAL,

  20. Small airways dysfunction and neutrophilic inflammation in bronchial biopsies and BAL in COPD

    NARCIS (Netherlands)

    Lapperre, Therese S.; Willems, Luuk N. A.; Timens, Wim; Rabe, Klaus F.; Hiemstra, Pieter S.; Postma, Dirkje S.; Sterk, Peter J.

    Background: The single-breath N-2 test (sbN(2)-test) is closely related to small airways pathology in resected lung specimens of smokers. We investigated whether uneven ventilation and airway closure are associated with specific markers of airway inflammation as obtained by bronchial biopsies, BAIL,

  1. Improved oxygenation during standing performance of deep breathing exercises with positive expiratory pressure after cardiac surgery: A randomized controlled trial.

    Science.gov (United States)

    Pettersson, Henrik; Faager, Gun; Westerdahl, Elisabeth

    2015-09-01

    Breathing exercises after cardiac surgery are often performed in a sitting position. It is unknown whether oxygenation would be better in the standing position. The aim of this study was to evaluate oxygenation and subjective breathing ability during sitting vs standing performance of deep breathing exercises on the second day after cardiac surgery. Patients undergoing coronary artery bypass grafting (n = 189) were randomized to sitting (controls) or standing. Both groups performed 3 × 10 deep breaths with a positive expiratory pressure device. Peripheral oxygen saturation was measured before, directly after, and 15 min after the intervention. Subjective breathing ability, blood pressure, heart rate, and pain were assessed. Oxygenation improved significantly in the standing group compared with controls directly after the breathing exercises (p < 0.001) and after 15 min rest (p = 0.027). The standing group reported better deep breathing ability compared with controls (p = 0.004). A slightly increased heart rate was found in the standing group (p = 0.047). After cardiac surgery, breathing exercises with positive expiratory pressure, performed in a standing position, significantly improved oxygenation and subjective breathing ability compared with sitting performance. Performance of breathing exercises in the standing position is feasible and could be a valuable treatment for patients with postoperative hypoxaemia.

  2. Lung hyperinflation stimulates the release of inflammatory mediators in spontaneously breathing subjects

    Directory of Open Access Journals (Sweden)

    L.M.S. Malbouisson

    2010-02-01

    Full Text Available Lung hyperinflation up to vital capacity is used to re-expand collapsed lung areas and to improve gas exchange during general anesthesia. However, it may induce inflammation in normal lungs. The objective of this study was to evaluate the effects of a lung hyperinflation maneuver (LHM on plasma cytokine release in 10 healthy subjects (age: 26.1 ± 1.2 years, BMI: 23.8 ± 3.6 kg/m². LHM was performed applying continuous positive airway pressure (CPAP with a face mask, increased by 3-cmH2O steps up to 20 cmH2O every 5 breaths. At CPAP 20 cmH2O, an inspiratory pressure of 20 cmH2O above CPAP was applied, reaching an airway pressure of 40 cmH2O for 10 breaths. CPAP was then decreased stepwise. Blood samples were collected before and 2 and 12 h after LHM. TNF-α, IL-1β, IL-6, IL-8, IL-10, and IL-12 were measured by flow cytometry. Lung hyperinflation significantly increased (P < 0.05 all measured cytokines (TNF-α: 1.2 ± 3.8 vs 6.4 ± 8.6 pg/mL; IL-1β: 4.9 ± 15.6 vs 22.4 ± 28.4 pg/mL; IL-6: 1.4 ± 3.3 vs 6.5 ± 5.6 pg/mL; IL-8: 13.2 ± 8.8 vs 33.4 ± 26.4 pg/mL; IL-10: 3.3 ± 3.3 vs 7.7 ± 6.5 pg/mL, and IL-12: 3.1 ± 7.9 vs 9 ± 11.4 pg/mL, which returned to basal levels 12 h later. A significant correlation was found between changes in pro- (IL-6 and anti-inflammatory (IL-10 cytokines (r = 0.89, P = 0.004. LHM-induced lung stretching was associated with an early inflammatory response in healthy spontaneously breathing subjects.

  3. The Tulip GT® airway versus the facemask and Guedel airway: a randomised, controlled, cross-over study by Basic Life Support-trained airway providers in anaesthetised patients.

    Science.gov (United States)

    Shaikh, A; Robinson, P N; Hasan, M

    2016-03-01

    We performed a randomised, controlled, cross-over study of lung ventilation by Basic Life Support-trained providers using either the Tulip GT® airway or a facemask with a Guedel airway in 60 anaesthetised patients. Successful ventilation was achieved if the provider produced an end-tidal CO2 > 3.5 kPa and a tidal volume > 250 ml in two of the first three breaths, within 60 sec and within two attempts. Fifty-seven (95%) providers achieved successful ventilation using the Tulip GT compared with 35 (58%) using the facemask (p Basic Life Support-trained airway providers. © 2015 The Association of Anaesthetists of Great Britain and Ireland.

  4. High altitude pulmonary edema and exercise at 4,400 meters on Mount McKinley. Effect of expiratory positive airway pressure.

    Science.gov (United States)

    Schoene, R B; Roach, R C; Hackett, P H; Harrison, G; Mills, W J

    1985-03-01

    Breathing against positive expiratory pressure has been used to improve gas exchange in many forms of pulmonary edema, and forced expiration against resistance during exercise has been advocated for climbing at high altitude as a method to optimize performance. To evaluate the effect of expiratory positive airway pressure (EPAP) on climbers with high altitude pulmonary edema (HAPE) and on exercise at high altitude, we studied four climbers with HAPE at rest and 13 healthy climbers during exercise on a bicycle ergometer at 4400 m. We measured minute ventilation (VI, L/min), arterial oxygen saturation (SaO2 percent), end-tidal carbon dioxide (PACO2, mm Hg), respiratory rate (RR), and heart rate (HR) during the last minute of a five minute interval at rest in the climbers with HAPE, and at rest, 300, and 600 kpm/minute workloads on a bicycle ergometer in the healthy subjects. The HAPE subjects demonstrated an increased SaO2 percent, no change in HR or VI, and a decrease in RR on EPAP as compared to control. In normal subjects, SaO2 percent, VI, and heart rate were significantly higher on EPAP 10 cm H2O than 0 cm H2O control (p less than 0.01, 0.01, and 0.05, respectively). The RR and PaCO2 were not significantly different. In summary, EPAP improves gas exchange in HAPE subjects at rest. The EPAP in normal subjects at high altitude resulted in a higher SaO2 percent at the expense of a higher VI and higher HR. These results suggest that the work of breathing is higher and the stroke volume lower on EPAP. The positive pressure mask may be an effective temporizing measure for victims of HAPE who cannot immediately go to a lower altitude.

  5. Auto-trilevel versus bilevel positive airway pressure ventilation for hypercapnic overlap syndrome patients.

    Science.gov (United States)

    Su, Mei; Huai, De; Cao, Juan; Ning, Ding; Xue, Rong; Xu, Meijie; Huang, Mao; Zhang, Xilong

    2018-03-01

    Although bilevel positive airway pressure (Bilevel PAP) therapy is usually used for overlap syndrome (OS), there is still a portion of OS patients in whom Bilevel PAP therapy could not simultaneously eliminate residual apnea events and hypercapnia. The current study was expected to explore whether auto-trilevel positive airway pressure (auto-trilevel PAP) therapy with auto-adjusting end expiratory positive airway pressure (EEPAP) can serve as a better alternative for these patients. From January of 2014 to June of 2016, 32 hypercapnic OS patients with stable chronic obstructive pulmonary diseases (COPD) and moderate-to-severe obstructive sleep apnea syndrome (OSAS) were recruited. Three variable modes of positive airway pressure (PAP) from the ventilator (Prisma25ST, Weinmann Inc., Germany) were applicated for 8 h per night. We performed the design of each mode at each night with an interval of two nights with no PAP treatment as a washout period among different modes. In Bilevel-1 mode (Bilevel-1), the expiratory positive airway pressure (EPAP) delivered from Bilevel PAP was always set as the lowest PAP for abolishment of snoring. For each patient, the inspiratory positive airway pressure (IPAP) was constantly set the same as the minimal pressure for keeping end-tidal CO 2 (ETCO 2 ) ≤45 mmHg for all three modes. However, the EPAP issued by Bilevel PAP in Bilevel-2 mode (Bilevel-2) was kept 3 cmH 2 O higher than that in Bilevel-1. In auto-trilevel mode (auto-trilevel) with auto-trilevel PAP, the initial part of EPAP was fixed at the same PAP as that in Bilevel-1 while the EEPAP was automatically regulated to rise at a range of ≤4 cmH 2 O based on nasal airflow wave changes. Comparisons were made for parameters before and during or following treatment as well as among different PAP therapy modes. The following parameters were compared such as nocturnal apnea hypopnea index (AHI), minimal SpO 2 (minSpO 2 ), arousal index, sleep structure and efficiency

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

    Science.gov (United States)

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

    2009-01-01

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

  7. The usefulness of dynamic MRI for diagnosing and assessing sleep breathing disorder

    Energy Technology Data Exchange (ETDEWEB)

    Moriwaki, Hiroto; Uchida, Akira; Chiba, Sachiko; Moriyama, Hiroshi [Jikei Univ., Tokyo (Japan). School of Medicine; Chiba, Shintarou; Yagi, Asako; Ohta, Masaji [Ohta General Hospital, Kawasaki, Kanagawa (Japan); Tokunaga, Masakazu [Kanagawa Prefecture Midwives and Nurses Training School (Japan). Hospital

    2003-04-01

    Polysomnography is useful for assessing the severity of sleep breathing disorder, including obstructive sleep apnea hypopnea syndrome. The clinical condition is difficult to understand completely, however, based on the apnea hypopnea index (AHI) alone, however, and longitudinal change of shape in the upper airway must be clarified. Most diagnoses of obstructive sites in the upper airway were diagnosed statically, so we attempted to assess changes in upper airway shape using dynamic magnetic resonance imaging (MRI), emphasizing the movement of tongue and lower chin, to analyze the relationship between AHI. Subjects were 62 patients with sleep breathing disorder examined by nocturnal polysomnography and dynamic MRI, assessing the change of shape in the upper airway. We concluded that: the group whose rotation angle of the tongue exceeded 6 deg and that the group whose distance of lower chin movement was longer during sleep than while awake were severe cases. (author)

  8. The usefulness of dynamic MRI for diagnosing and assessing sleep breathing disorder

    International Nuclear Information System (INIS)

    Moriwaki, Hiroto; Uchida, Akira; Chiba, Sachiko; Moriyama, Hiroshi; Tokunaga, Masakazu

    2003-01-01

    Polysomnography is useful for assessing the severity of sleep breathing disorder, including obstructive sleep apnea hypopnea syndrome. The clinical condition is difficult to understand completely, however, based on the apnea hypopnea index (AHI) alone, however, and longitudinal change of shape in the upper airway must be clarified. Most diagnoses of obstructive sites in the upper airway were diagnosed statically, so we attempted to assess changes in upper airway shape using dynamic magnetic resonance imaging (MRI), emphasizing the movement of tongue and lower chin, to analyze the relationship between AHI. Subjects were 62 patients with sleep breathing disorder examined by nocturnal polysomnography and dynamic MRI, assessing the change of shape in the upper airway. We concluded that: the group whose rotation angle of the tongue exceeded 6 deg and that the group whose distance of lower chin movement was longer during sleep than while awake were severe cases. (author)

  9. Retrotracheal Extraskeletal Ewing's Sarcoma: Case Report and Discussion on Airway Management.

    Science.gov (United States)

    Van Der Meer, Graeme; Linkhorn, Hannah; Gruber, Maayan; Mahadevan, Murali; Barber, Colin

    2017-03-01

    Extraskeletal Ewing's sarcoma is a rare tumor, and the management of airway compromise in case of cervical Ewing's sarcoma has not been established. This report describes the case of a patient with retrotracheal Ewing's sarcoma and discusses a successful approach to airway management. A 12-year-old male presented with a 2-week history of sore throat and sleep-disordered breathing and 48 hours of stridor. Imaging confirmed a retrotracheal soft tissue mass with airway compromise. A planned and controlled approach to his airway management resulted in a secure airway prior to definitive treatment.

  10. Sleep-disordered breathing and mortality: a prospective cohort study.

    OpenAIRE

    Naresh M Punjabi; Brian S Caffo; James L Goodwin; Daniel J Gottlieb; Anne B Newman; George T O'Connor; David M Rapoport; Susan Redline; Helaine E Resnick; John A Robbins; Eyal Shahar; Mark L Unruh; Jonathan M Samet

    2009-01-01

    Editors' Summary Background About 1 in 10 women and 1 in 4 men have a chronic condition called sleep-disordered breathing although most are unaware of their problem. Sleep-disordered breathing, which is commonest in middle-aged and elderly people, is characterized by numerous, brief (10 second or so) interruptions of breathing during sleep. These interruptions, which usually occur when relaxation of the upper airway muscles decreases airflow, lower the level of oxygen in the blood and, as a r...

  11. Analysis of Exhaled Breath for Disease Detection

    Science.gov (United States)

    Amann, Anton; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Ligor, Tomasz; Jezierski, Tadeusz; Pleil, Joachim; Risby, Terence

    2014-06-01

    Breath analysis is a young field of research with great clinical potential. As a result of this interest, researchers have developed new analytical techniques that permit real-time analysis of exhaled breath with breath-to-breath resolution in addition to the conventional central laboratory methods using gas chromatography-mass spectrometry. Breath tests are based on endogenously produced volatiles, metabolites of ingested precursors, metabolites produced by bacteria in the gut or the airways, or volatiles appearing after environmental exposure. The composition of exhaled breath may contain valuable information for patients presenting with asthma, renal and liver diseases, lung cancer, chronic obstructive pulmonary disease, inflammatory lung disease, or metabolic disorders. In addition, oxidative stress status may be monitored via volatile products of lipid peroxidation. Measurement of enzyme activity provides phenotypic information important in personalized medicine, whereas breath measurements provide insight into perturbations of the human exposome and can be interpreted as preclinical signals of adverse outcome pathways.

  12. Secondhand smoke exposure induces acutely airway acidification and oxidative stress.

    Science.gov (United States)

    Kostikas, Konstantinos; Minas, Markos; Nikolaou, Eftychia; Papaioannou, Andriana I; Liakos, Panagiotis; Gougoura, Sofia; Gourgoulianis, Konstantinos I; Dinas, Petros C; Metsios, Giorgos S; Jamurtas, Athanasios Z; Flouris, Andreas D; Koutedakis, Yiannis

    2013-02-01

    Previous studies have shown that secondhand smoke induces lung function impairment and increases proinflammatory cytokines. The aim of the present study was to evaluate the acute effects of secondhand smoke on airway acidification and airway oxidative stress in never-smokers. In a randomized controlled cross-over trial, 18 young healthy never-smokers were assessed at baseline and 0, 30, 60, 120, 180 and 240 min after one-hour secondhand smoke exposure at bar/restaurant levels. Exhaled NO and CO measurements, exhaled breath condensate collection (for pH, H(2)O(2) and NO(2)(-)/NO(3)(-) measurements) and spirometry were performed at all time-points. Secondhand smoke exposure induced increases in serum cotinine and exhaled CO that persisted until 240 min. Exhaled breath condensate pH decreased immediately after exposure (p secondhand smoke induced airway acidification and increased airway oxidative stress, accompanied by significant impairment of lung function. Despite the reversal in EBC pH and lung function, airway oxidative stress remained increased 4 h after the exposure. Clinical trial registration number (EudraCT): 2009-013545-28. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Spontaneous breathing during lung-protective ventilation in an experimental acute lung injury model: high transpulmonary pressure associated with strong spontaneous breathing effort may worsen lung injury.

    Science.gov (United States)

    Yoshida, Takeshi; Uchiyama, Akinori; Matsuura, Nariaki; Mashimo, Takashi; Fujino, Yuji

    2012-05-01

    We investigated whether potentially injurious transpulmonary pressure could be generated by strong spontaneous breathing and exacerbate lung injury even when plateau pressure is limited to ventilation, each combined with weak or strong spontaneous breathing effort. Inspiratory pressure for low tidal volume ventilation was set at 10 cm H2O and tidal volume at 6 mL/kg. For moderate tidal volume ventilation, the values were 20 cm H2O and 7-9 mL/kg. The groups were: low tidal volume ventilation+spontaneous breathingweak, low tidal volume ventilation+spontaneous breathingstrong, moderate tidal volume ventilation+spontaneous breathingweak, and moderate tidal volume ventilation+spontaneous breathingstrong. Each group had the same settings for positive end-expiratory pressure of 8 cm H2O. Respiratory variables were measured every 60 mins. Distribution of lung aeration and alveolar collapse were histologically evaluated. Low tidal volume ventilation+spontaneous breathingstrong showed the most favorable oxygenation and compliance of respiratory system, and the best lung aeration. By contrast, in moderate tidal volume ventilation+spontaneous breathingstrong, the greatest atelectasis with numerous neutrophils was observed. While we applied settings to maintain plateau pressure at ventilation+spontaneous breathingstrong, transpulmonary pressure rose >33 cm H2O. Both minute ventilation and respiratory rate were higher in the strong spontaneous breathing groups. Even when plateau pressure is limited to mechanical ventilation, transpulmonary pressure and tidal volume should be strictly controlled to prevent further lung injury.

  14. Adherence to continuous positive airway pressure in adults with an intellectual disability

    NARCIS (Netherlands)

    Luijks, K.A.; Vandenbussche, N.L.; Pevernagie, D.; Overeem, S.; Pillen, S.

    STUDY OBJECTIVES: This retrospective study evaluated the feasibility of continuous positive airway pressure (CPAP) therapy in adults with intellectual disabilities (ID). METHODS: CPAP therapy of 24 obstructive sleep apnea syndrome (OSA) patients with ID were compared to age- and sex-matched adults

  15. Comparison Study of Airway Reactivity Outcomes due to a Pharmacologic Challenge Test: Impulse Oscillometry versus Least Mean Squared Analysis Techniques

    Directory of Open Access Journals (Sweden)

    Elena Rodriguez

    2013-01-01

    Full Text Available The technique of measuring transpulmonary pressure and respiratory airflow with manometry and pneumotachography using the least mean squared analysis (LMS has been used broadly in both preclinical and clinical settings for the evaluation of neonatal respiratory function during tidal volume breathing for lung tissue and airway frictional mechanical properties measurements. Whereas the technique of measuring respiratory function using the impulse oscillation technique (IOS involves the assessment of the relationship between pressure and flow using an impulse signal with a range of frequencies, requires less cooperation and provides more information on total respiratory system resistance (chest wall, lung tissue, and airways. The present study represents a preclinical animal study to determine whether these respiratory function techniques (LMS and IOS are comparable in detecting changes in respiratory resistance derived from a direct pharmacological challenge.

  16. BreathSens: A Continuous On-Bed Respiratory Monitoring System With Torso Localization Using an Unobtrusive Pressure Sensing Array.

    Science.gov (United States)

    Liu, Jason J; Huang, Ming-Chun; Xu, Wenyao; Zhang, Xiaoyi; Stevens, Luke; Alshurafa, Nabil; Sarrafzadeh, Majid

    2015-09-01

    The ability to continuously monitor respiration rates of patients in homecare or in clinics is an important goal. Past research showed that monitoring patient breathing can lower the associated mortality rates for long-term bedridden patients. Nowadays, in-bed sensors consisting of pressure sensitive arrays are unobtrusive and are suitable for deployment in a wide range of settings. Such systems aim to extract respiratory signals from time-series pressure sequences. However, variance of movements, such as unpredictable extremities activities, affect the quality of the extracted respiratory signals. BreathSens, a high-density pressure sensing system made of e-Textile, profiles the underbody pressure distribution and localizes torso area based on the high-resolution pressure images. With a robust bodyparts localization algorithm, respiratory signals extracted from the localized torso area are insensitive to arbitrary extremities movements. In a study of 12 subjects, BreathSens demonstrated its respiratory monitoring capability with variations of sleep postures, locations, and commonly tilted clinical bed conditions.

  17. The effect of sleep onset on upper airway muscle activity in patients with sleep apnoea versus controls

    Science.gov (United States)

    Fogel, Robert B; Trinder, John; White, David P; Malhotra, Atul; Raneri, Jill; Schory, Karen; Kleverlaan, Darci; Pierce, Robert J

    2005-01-01

    Pharyngeal dilator muscles are important in the pathophysiology of obstructive sleep apnoea syndrome (OSA). We have previously shown that during wakefulness, the activity of both the genioglossus (GGEMG) and tensor palatini (TPEMG) is greater in patients with OSA compared with controls. Further, EMG activity decreases at sleep onset, and the decrement is greater in apnoea patients than in healthy controls. In addition, it is known that the prevalence of OSA is greater in middle-aged compared with younger men. Thus, we had two goals in this study. First we compared upper airway muscle activity between young and middle-aged healthy men compared with men with OSA. We also explored the mechanisms responsible for the decrement in muscle activity at sleep onset in these groups. We investigated muscle activity, ventilation , and upper airway resistance (UAR) during wakefulness and sleep onset (transition from α to θ EEG activity) in all three groups. Measurements were obtained during basal breathing (BB) and nasal continuous positive airway pressure (CPAP) was applied to reduce negative pressure-mediated muscle activation). We found that during wakefulness there was a gradation of GGEMG and UAR (younger < older < OSA) and that muscle activity was reduced by the application of nasal CPAP (to a greater degree in the OSA patients). Although CPAP eliminated differences in UAR during wakefulness and sleep, GGEMG remained greater in the OSA patients. During sleep onset, a greater initial fall in GGEMG was seen in the OSA patients followed by subsequent muscle recruitment in the third to fifth breaths following the α to θ transition. On the CPAP night, and GGEMG still fell further in the OSA patients compared with control subjects. CPAP prevented the rise in UAR at sleep onset along with the associated recruitment in GGEMG. Differences in TPEMG among the groups were not significant. These data suggest that the middle-aged men had upper airway function midway between that of

  18. The Impact of Resonance Frequency Breathing on Measures of Heart Rate Variability, Blood Pressure, and Mood

    Directory of Open Access Journals (Sweden)

    Patrick R. Steffen

    2017-08-01

    Full Text Available Heart rate variability biofeedback (HRVB significantly improves heart rate variability (HRV. Breathing at resonance frequency (RF, approximately 6 breaths/min constitutes a key part of HRVB training and is hypothesized to be a pathway through which biofeedback improves HRV. No studies to date, however, have experimentally examined whether RF breathing impacts measures of HRV. The present study addressed this question by comparing three groups: the RF group breathed at their determined RF for 15 min; the RF + 1 group breathed at 1 breath/min higher than their determined RF for 15 min; and the third group sat quietly for 15 min. After this 15-min period, all groups participated in the Paced Auditory Serial Addition Task (PASAT for 8 min, and then sat quietly during a 10-min recovery period. HRV, blood pressure, and mood were measured throughout the experiment. Groups were not significantly different on any of the measures at baseline. After the breathing exercise, the RF group reported higher positive mood than the other two groups and a significantly higher LF/HF HRV ratio relative to the control group, a key goal in HRVB training (p < 0.05. Additionally, the RF group showed lower systolic blood pressure during the PASAT and during the recovery period relative to the control group, with the RF + 1 group not being significantly different from either group (p < 0.05. Overall, RF breathing appears to play an important role in the positive effect HRVB has on measures of HRV.

  19. Continuous positive airway pressure: Physiology and comparison of devices.

    Science.gov (United States)

    Gupta, Samir; Donn, Steven M

    2016-06-01

    Nasal continuous positive airway pressure (CPAP) is increasingly used for respiratory support in preterm babies at birth and after extubation from mechanical ventilation. Various CPAP devices are available for use that can be broadly grouped into continuous flow and variable flow. There are potential physiologic differences between these CPAP systems and the choice of a CPAP device is too often guided by individual expertise and experience rather than by evidence. When interpreting the evidence clinicians should take into account the pressure generation sources, nasal interface, and the factors affecting the delivery of pressure, such as mouth position and respiratory drive. With increasing use of these devices, better monitoring techniques are required to assess the efficacy and early recognition of babies who are failing and in need of escalated support. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Cerebral hemodynamics in patients with obstructive sleep apnea syndrome monitored with near-infrared spectroscopy (NIRS) during positive airways pressure (CPAP) therapy: a pilot study

    Science.gov (United States)

    Zhang, Zhongxing; Schneider, Maja; Laures, Marco; Fritschi, Ursula; Lehner, Isabella; Qi, Ming; Khatami, Ramin

    2014-03-01

    In obstructive sleep apnea syndrome (OSA) the periodic reduction or cessation of breathing due to narrowing or occlusion of the upper airway during sleep leads to daytime symptoms and increased cardiovascular risk, including stroke. The higher risk of stroke is related to the impairment in cerebral vascular autoregulation. Continuous positive airways pressure (CPAP) therapy at night is the most effective treatment for OSA. However, there is no suitable bedside monitoring method evaluating the treatment efficacy of CPAP therapy, especially to monitor the recovery of cerebral hemodynamics. NIRS is ideally suited for non-invasive monitoring the cerebral hemodynamics during sleep. In this study, we will for first time assess dynamic changes of cerebral hemodynamics during nocturnal CPAP therapy in 3 patients with OSA using NIRS. We found periodic oscillations in HbO2, HHb, tissue oxygenation index (TOI) and blood volume associated with periodic apnea events without CPAP in all OSA patients. These oscillations were gradually attenuated and finally eliminated with the stepwise increments of CPAP pressures. The oscillations were totally eliminated in blood volume earlier than in other hemodynamic parameters. These results suggested that 1) the cerebral hemodynamic oscillations induced by OSA events can effectively be attenuated by CPAP therapy, and 2) blood flow and blood volume recovered first during CPAP therapy, followed by the recovery of oxygen consumption. Our study suggested that NIRS is a useful tool to evaluate the efficacy of CPAP therapy in patients with OSA bedside and in real time.

  1. Comparison of sprinting vs non-sprinting to wean nasal continuous positive airway pressure off in very preterm infants.

    Science.gov (United States)

    Eze, N; Murphy, D; Dhar, V; Rehan, V K

    2018-02-01

    Though nasal continuous positive airway pressure (NCPAP) is commonly used for non-invasive neonatal respiratory support, the optimal method of weaning NCPAP is not established. In this prospective, two-center randomized control trial we hypothesize that gradually increasing spontaneous breathing time off NCPAP increases successful weaning from NCPAP in infants born 0.05). It took 1.3 (1 to 1.75) (median (IQR)) attempts and 7 (7 to 7) days to wean NCPAP off in the sprinting group vs 1.3 (1 to 1.75) attempts and 7 (7 to 10) days in the non-sprinting group (P>0.05). Additionally, no differences in the secondary outcomes of bronchopulmonary dysplasia, severe retinopathy of prematurity (⩾stage 3), periventricular leukomalacia and length of stay were noted between the two groups. Weaning NCPAP via sprinting or non-sprinting protocol is comparable, not only for successful weaning but also for the occurrence of common neonatal morbidities that impact the long-term outcome in premature infants (ClinicalTrials.gov number, NCT02819050).

  2. Clearing the airway by an emergency care provider in the prehospital emergency care

    OpenAIRE

    NOVOTNÁ, Magdalena

    2008-01-01

    Clearing an obstructed airway to facilitate breathing is a critical element of airway management. It is the emergency care provider who administers first aid and he/she has to master the technique of opening the airway as well as the aspiration prevention. The right airway management may avert the life-threatening condition of an injured person. The thesis is focused on the possibilities of clearing the airway by the emergency care provider in the Central Bohemian region. Techniques of openin...

  3. Airway malacia in children with achondroplasia.

    Science.gov (United States)

    Dessoffy, Kimberly E; Modaff, Peggy; Pauli, Richard M

    2014-02-01

    This study was undertaken to assess the frequency of airway malacia in infants and young children with achondroplasia, a population well known to be at risk for a variety of respiratory problems. We also wished to evaluate what, if any, contribution airway malacia makes to the complex respiratory issues that may be present in those with achondroplasia. Retrospective chart review of all infants and young children with achondroplasia who were assessed through the Midwest Regional Bone Dysplasia Clinics from 1985 through 2012 (n = 236) was completed. Records of comprehensive clinical examinations, polysomnographic assessments, and airway visualization were reviewed and abstracted using a data collection form. Analyses were completed comparing the group with and those without evidence for airway malacia. Thirteen of 236 patients (5.5%) were found to have airway malacia. Most of those affected had lower airway involvement (9/13). The presence of airway malacia was correlated with an increased occurrence of obstructive sleep apnea as well as need for oxygen supplementation, airway surgeries and tracheostomy placement. Although estimates of the frequency of airway malacia in the general population are limited, its frequency in children with achondroplasia appears to be much higher than any published general population estimate. The presence of airway malacia appears to confound other breathing abnormalities in this population and results in the need for more invasive airway treatments. © 2013 Wiley Periodicals, Inc.

  4. Stroke and sleep-disordered breathing: A relationship under construction.

    Science.gov (United States)

    Parra, Olga; Arboix, Adrià

    2016-02-16

    The association between sleep-disordered breathing (SDB) and cardiovascular risk has been the focus of attention in recent years. Sleep disorders are emerging risk factors for cardiovascular disease and have been related to the whole spectrum of stroke, including transient ischemic attack, ischemic cerebral infarction and intracerebral haemorrhage. It has been shown that lacunar stroke or lacunar infarctions affecting the internal capsule or the protuberance are associated with a higher frequency of SDB. Acute stroke patients with associated SDB have a worse prognosis and a higher mortality as compared to patients with first-ever stroke without SDB. Preliminary studies provide evidence of the usefulness of treatment with continuous positive airway pressure when SDB is present in stroke patients.

  5. A new method of maintaining airway during nasotracheal intubation--the hand mask technique.

    Science.gov (United States)

    Wu, R S; Wong, D S; Chung, P C; Tan, P P

    1993-09-01

    The efficacy of a new method (The hand mask technique) for airway maintenance during nasotracheal intubation was evaluated in our randomized crossover study. Sixty, age less than 50, ASA physical status class I-II patients undergoing surgery for the extremities with informed consent were randomly chosen for the study. Pulse oximeter, capnometer, EKG, blood pressure monitor and a peripheral nerve stimulator were attached to the patients before induction for continuous monitoring. An arterial cannula was inserted for intermittent blood gas sampling. After baseline room air blood gas data had been obtained from the spontaneously breathing patients, a flow rate of 6L/min pure oxygen was applied through a loosely fitted face mask and a semi-closed anesthesia breathing circuit for a period of 5 minutes. An arterial blood sample was drawn and the patients were put under general anesthesia with full muscle relaxation thereafter. Patients were then randomly assigned into two groups according to the ventilation technique used. Group A patients (n = 30) were manually ventilated first through a face mask for ten minutes and then the hand mask technique for another ten minutes. Blood gas data was sampled and heart rate, blood pressure, peak inspiratory airway pressure and end tidal CO2 were recorded immediately after each ventilation technique. For patients in Group B (n = 30), the sequence of the two ventilation technique were reversed. The results showed significant increases in PaO2 after artificial ventilation in both groups (No significant difference in results between the two groups) and less incidence of nasal bleeding in Group A.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. A prospective crossover comparison of neurally adjusted ventilatory assist and pressure-support ventilation in a pediatric and neonatal intensive care unit population.

    LENUS (Irish Health Repository)

    Breatnach, Cormac

    2012-02-01

    OBJECTIVE: To compare neurally adjusted ventilatory assist ventilation with pressure-support ventilation. DESIGN: Prospective, crossover comparison study. SETTING: Tertiary care pediatric and neonatal intensive care unit. PATIENTS: Sixteen ventilated infants and children: mean age = 9.7 months (range = 2 days-4 yrs) and mean weight = 6.2 kg (range = 2.4-13.7kg). INTERVENTIONS: A modified nasogastric tube was inserted and correct positioning was confirmed. Patients were ventilated in pressure-support mode with a pneumatic trigger for a 30-min period and then in neurally adjusted ventilatory assist mode for up to 4 hrs. MEASUREMENTS AND MAIN RESULTS: Data collected for comparison included activating trigger (neural vs. pneumatic), peak and mean airway pressures, expired minute and tidal volumes, heart rate, respiratory rate, pulse oximetry, end-tidal CO2 and arterial blood gases. Synchrony was improved in neurally adjusted ventilatory assist mode with 65% (+\\/-21%) of breaths triggered neurally vs. 35% pneumatically (p < .001) and 85% (+\\/-8%) of breaths cycled-off neurally vs. 15% pneumatically (p = .0001). The peak airway pressure in neurally adjusted ventilatory assist mode was significantly lower than in pressure-support mode with a 28% decrease in pressure after 30 mins (p = .003) and 32% decrease after 3 hrs (p < .001). Mean airway pressure was reduced by 11% at 30 mins (p = .13) and 9% at 3 hrs (p = .31) in neurally adjusted ventilatory assist mode although this did not reach statistical significance. Patient hemodynamics and gas exchange remained stable for the study period. No adverse patient events or device effects were noted. CONCLUSIONS: In a neonatal and pediatric intensive care unit population, ventilation in neurally adjusted ventilatory assist mode was associated with improved patient-ventilator synchrony and lower peak airway pressure when compared with pressure-support ventilation with a pneumatic trigger. Ventilating patients in this new mode

  7. Interaction between peri-operative blood transfusion, tidal volume, airway pressure and postoperative ARDS: an individual patient data meta-analysis.

    Science.gov (United States)

    Serpa Neto, Ary; Juffermans, Nicole P; Hemmes, Sabrine N T; Barbas, Carmen S V; Beiderlinden, Martin; Biehl, Michelle; Fernandez-Bustamante, Ana; Futier, Emmanuel; Gajic, Ognjen; Jaber, Samir; Kozian, Alf; Licker, Marc; Lin, Wen-Qian; Memtsoudis, Stavros G; Miranda, Dinis Reis; Moine, Pierre; Paparella, Domenico; Ranieri, Marco; Scavonetto, Federica; Schilling, Thomas; Selmo, Gabriele; Severgnini, Paolo; Sprung, Juraj; Sundar, Sugantha; Talmor, Daniel; Treschan, Tanja; Unzueta, Carmen; Weingarten, Toby N; Wolthuis, Esther K; Wrigge, Hermann; de Abreu, Marcelo Gama; Pelosi, Paolo; Schultz, Marcus J

    2018-01-01

    Transfusion of blood products and mechanical ventilation with injurious settings are considered risk factors for postoperative lung injury in surgical Patients. A systematic review and individual patient data meta-analysis was done to determine the independent effects of peri-operative transfusion of blood products, intra-operative tidal volume and airway pressure in adult patients undergoing mechanical ventilation for general surgery, as well as their interactions on the occurrence of postoperative acute respiratory distress syndrome (ARDS). Observational studies and randomized trials were identified by a systematic search of MEDLINE, CINAHL, Web of Science, and CENTRAL and screened for inclusion into a meta-analysis. Individual patient data were obtained from the corresponding authors. Patients were stratified according to whether they received transfusion in the peri-operative period [red blood cell concentrates (RBC) and/or fresh frozen plasma (FFP)], tidal volume size [≤7 mL/kg predicted body weight (PBW), 7-10 and >10 mL/kg PBW] and airway pressure level used during surgery (≤15, 15-20 and >20 cmH 2 O). The primary outcome was development of postoperative ARDS. Seventeen investigations were included (3,659 patients). Postoperative ARDS occurred in 40 (7.2%) patients who received at least one blood product compared to 40 patients (2.5%) who did not [adjusted hazard ratio (HR), 2.32; 95% confidence interval (CI), 1.25-4.33; P=0.008]. Incidence of postoperative ARDS was highest in patients ventilated with tidal volumes of >10 mL/kg PBW and having airway pressures of >20 cmH 2 O receiving both RBC and FFP, and lowest in patients ventilated with tidal volume of ≤7 mL/kg PBW and having airway pressures of ≤15 cmH 2 O with no transfusion. There was a significant interaction between transfusion and airway pressure level (P=0.002) on the risk of postoperative ARDS. Peri-operative transfusion of blood products is associated with an increased risk of

  8. Experimental intra-abdominal hypertension influences airway pressure limits for lung protective mechanical ventilation.

    Science.gov (United States)

    Cortes-Puentes, Gustavo A; Cortes-Puentes, Luis A; Adams, Alexander B; Anderson, Christopher P; Marini, John J; Dries, David J

    2013-06-01

    Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) may complicate monitoring of pulmonary mechanics owing to their impact on the respiratory system. However, recommendations for mechanical ventilation of patients with IAH/ACS and the interpretation of thoracoabdominal interactions remain unclear. Our study aimed to characterize the influence of elevated intra-abdominal pressure (IAP) and positive end-expiratory pressure (PEEP) on airway plateau pressure (PPLAT) and bladder pressure (PBLAD). Nine deeply anesthetized swine were mechanically ventilated via tracheostomy: volume-controlled mode at tidal volume (VT) of 10 mL/kg, frequency of 15, inspiratory-expiratory ratio of 1:2, and PEEP of 1 and 10 cm H2O (PEEP1 and PEEP10, respectively). A tracheostomy tube was placed in the peritoneal cavity, and IAP levels of 5, 10, 15, 20, and 25 mm Hg were applied, using a continuous positive airway pressure system. At each IAP level, PBLAD and airway pressure measurements were performed during both PEEP1 and PEEP10. PBLAD increased as experimental IAP rose (y = 0.83x + 0.5; R = 0.98; p < 0.001 at PEEP1). Minimal underestimation of IAP by PBLAD was observed (-2.5 ± 0.8 mm Hg at an IAP of 10-25 mm Hg). Applying PEEP10 did not significantly affect the correlation between experimental IAP and PBLAD. Approximately 50% of the PBLAD (in cm H2O) was reflected by changes in PPLAT, regardless of the PEEP level applied. Increasing IAP did not influence hemodynamics at any level of IAP generated. With minimal underestimation, PBLAD measurements closely correlated with experimentally regulated IAP, independent of the PEEP level applied. For each PEEP level applied, a constant proportion (approximately 50%) of measured PBLAD (in cm H2O) was reflected in PPLAT. A higher safety threshold for PPLAT should be considered in the setting of IAH/ACS as the clinician considers changes in VT. A strategy of reducing VT to cap PPLAT at widely recommended values may not be

  9. Clinical predictors of central sleep apnea evoked by positive airway pressure titration.

    Science.gov (United States)

    Moro, Marilyn; Gannon, Karen; Lovell, Kathy; Merlino, Margaret; Mojica, James; Bianchi, Matt T

    2016-01-01

    Treatment-emergent central sleep apnea (TECSA), also called complex apnea, occurs in 5%-15% of sleep apnea patients during positive airway pressure (PAP) therapy, but the clinical predictors are not well understood. The goal of this study was to explore possible predictors in a clinical sleep laboratory cohort, which may highlight those at risk during clinical management. We retrospectively analyzed 728 patients who underwent PAP titration (n=422 split-night; n=306 two-night). Demographics and self-reported medical comorbidities, medications, and behaviors as well as standard physiological parameters from the polysomnography (PSG) data were analyzed. We used regression analysis to assess predictors of binary presence or absence of central apnea index (CAI) ≥5 during split-night PSG (SN-PSG) versus full-night PSG (FN-PSG) titrations. CAI ≥5 was present in 24.2% of SN-PSG and 11.4% of FN-PSG patients during titration. Male sex, maximum continuous positive airway pressure, and use of bilevel positive airway pressure were predictors of TECSA, and rapid eye movement dominance was a negative predictor, for both SN-PSG and FN-PSG patients. Self-reported narcotics were a positive predictor of TECSA, and the time spent in stage N2 sleep was a negative predictor only for SN-PSG patients. Self-reported history of stroke and the CAI during the diagnostic recording predicted TECSA only for FN-PSG patients. Clinical predictors of treatment-evoked central apnea spanned demographic, medical history, sleep physiology, and titration factors. Improved predictive models may be increasingly important as diagnostic and therapeutic modalities move away from the laboratory setting, even as PSG remains the gold standard for characterizing primary central apnea and TECSA.

  10. Understanding the use of continuous oscillating positive airway pressure (bubble CPAP) to treat neonatal respiratory disease: an engineering approach.

    Science.gov (United States)

    Manilal-Reddy, P I; Al-Jumaily, A M

    2009-01-01

    A continuous oscillatory positive airway pressure with pressure oscillations incidental to the mean airway pressure (bubble CPAP) is defined as a modified form of traditional continuous positive airway pressure (CPAP) delivery where pressure oscillations in addition to CPAP are administered to neonates with lung diseases. The mechanical effect of the pressure oscillations on lung performance is investigated by formulating mathematical models of a typical bubble CPAP device and a simple representation of a neonatal respiratory system. Preliminary results of the respiratory system's mechanical response suggest that bubble CPAP may improve lung performance by minimizing the respiratory system impedance and that the resonant frequency of the respiratory system may be a controlling factor. Additional steps in terms of clinical trials and a more complex respiratory system model are required to gain a deeper insight into the mechanical receptiveness of the respiratory system to pressure oscillations. However, the current results are promising in that they offer a deeper insight into the trends of variations that can be expected in future extended models as well as the model philosophies that need to be adopted to produce results that are compatible with experimental verification.

  11. Role of Positive Airway Pressure Therapy for Obstructive Sleep Apnea in Patients With Stroke: A Randomized Controlled Trial

    Science.gov (United States)

    Gupta, Anupama; Shukla, Garima; Afsar, Mohammed; Poornima, Shivani; Pandey, Ravindra M.; Goyal, Vinay; Srivastava, Achal; Vibha, Deepti; Behari, Madhuri

    2018-01-01

    Registration: Registry: Clinical Trials Registry - India, CTRI Registration No: CTRI/2016/07.007104, Title: Sleep Disordered Breathing in stroke patients: Effect of treatment trial, URL: http://ctri.nic.in/Clinicaltrials/showallp.php?mid1=8682&EncHid=&userName=sleep%20disordered%20breathing Citation: Gupta A, Shukla G, Afsar M, Poornima S, Pandey RM, Goyal V, Srivastava A, Vibha D, Behari M. Role of positive airway pressure therapy for obstructive sleep apnea in patients with stroke: a randomized controlled trial. J Clin Sleep Med. 2018;14(4):511–521. PMID:29609704

  12. Sleep-Disordered Breathing in Neuromuscular Disease: Diagnostic and Therapeutic Challenges.

    Science.gov (United States)

    Aboussouan, Loutfi S; Mireles-Cabodevila, Eduardo

    2017-10-01

    Normal sleep-related rapid eye movement sleep atonia, reduced lung volumes, reduced chemosensitivity, and impaired airway dilator activity become significant vulnerabilities in the setting of neuromuscular disease. In that context, the compounding effects of respiratory muscle weakness and disease-specific features that promote upper airway collapse or cause dilated cardiomyopathy contribute to various sleep-disordered breathing events. The reduction in lung volumes with neuromuscular disease is further compromised by sleep and the supine position, exaggerating the tendency for upper airway collapse and desaturation with sleep-disordered breathing events. The most commonly identified events are diaphragmatic/pseudo-central, due to a decrease in the rib cage contribution to the tidal volume during phasic rapid eye movement sleep. Obstructive and central sleep apneas are also common. Noninvasive ventilation can improve survival and quality of sleep but should be used with caution in the context of dilated cardiomyopathy or significant bulbar symptoms. Noninvasive ventilation can also trigger sleep-disordered breathing events, including ineffective triggering, autotriggering, central sleep apnea, and glottic closure, which compromise the potential benefits of the intervention by increasing arousals, reducing adherence, and impairing sleep architecture. Polysomnography plays an important diagnostic and therapeutic role by correctly categorizing sleep-disordered events, identifying sleep-disordered breathing triggered by noninvasive ventilation, and improving noninvasive ventilation settings. Optimal management may require dedicated hypoventilation protocols and a technical staff well versed in the identification and troubleshooting of respiratory events. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  13. Tonsillectomy or adenotonsillectomy versus non-surgical management for obstructive sleep-disordered breathing in children

    NARCIS (Netherlands)

    Venekamp, Roderick P; Hearne, Benjamin J; Chandrasekharan, Deepak; Blackshaw, Helen; Lim, Jerome; Schilder, Anne G M

    2015-01-01

    BACKGROUND: Obstructive sleep-disordered breathing (oSDB) is a condition that encompasses breathing problems when asleep, due to an obstruction of the upper airways, ranging in severity from simple snoring to obstructive sleep apnoea syndrome (OSAS). It affects both children and adults. In children,

  14. Fast or Slow Rescue Ventilations: A Predictive Model of Gastric Inflation.

    Science.gov (United States)

    Fitz-Clarke, John R

    2018-05-01

    Rescue ventilations are given during respiratory and cardiac arrest. Tidal volume must assure oxygen delivery; however, excessive pressure applied to an unprotected airway can cause gastric inflation, regurgitation, and pulmonary aspiration. The optimal technique provides mouth pressure and breath duration that minimize gastric inflation. It remains unclear if breath delivery should be fast or slow, and how inflation time affects the division of gas flow between the lungs and esophagus. A physiological model was used to predict and compare rates of gastric inflation and to determine ideal ventilation duration. Gas flow equations were based on standard pulmonary physiology. Gastric inflation was assumed to occur whenever mouth pressure exceeded lower esophageal sphincter pressure. Mouth pressure profiles that approximated mouth-to-mouth ventilation and bag-valve-mask ventilation were investigated. Target tidal volumes were set to 0.6 and 1.0 L. Compliance and airway resistance were varied. Rapid breaths shorter than 1 s required high mouth pressures, up to 25 cm H 2 O to achieve the target lung volume, which thus promotes gastric inflation. Slow breaths longer than 1 s permitted lower mouth pressures but increased time over which airway pressure exceeded lower esophageal sphincter pressure. The gastric volume increased with breath durations that exceeded 1 s for both mouth pressure profiles. Breath duration of ∼1.0 s caused the least gastric inflation in most scenarios. Very low esophageal sphincter pressure favored a shift toward 0.5 s. High resistance and low compliance each increased gastric inflation and altered ideal breath times. The model illustrated a general theory of optimal rescue ventilation. Breath duration with an unprotected airway should be 1 s to minimize gastric inflation. Short pressure-driven and long duration-driven gastric inflation regimens provide a unifying explanation for results in past studies. Copyright © 2018 by Daedalus Enterprises.

  15. Medication effects on sleep and breathing.

    Science.gov (United States)

    Seda, Gilbert; Tsai, Sheila; Lee-Chiong, Teofilo

    2014-09-01

    Sleep respiration is regulated by circadian, endocrine, mechanical and chemical factors, and characterized by diminished ventilatory drive and changes in Pao2 and Paco2 thresholds. Hypoxemia and hypercapnia are more pronounced during rapid eye movement. Breathing is influenced by sleep stage and airway muscle tone. Patient factors include medical comorbidities and body habitus. Medications partially improve obstructive sleep apnea and stabilize periodic breathing at altitude. Potential adverse consequences of medications include precipitation or worsening of disorders. Risk factors for adverse medication effects include aging, medical disorders, and use of multiple medications that affect respiration. Published by Elsevier Inc.

  16. Continuous positive airway pressure for the treatment of obstructive sleep apnea.

    Science.gov (United States)

    Nurwidya, Fariz; Susanto, Agus Dwi; Juzar, Dafsah A; Kobayashi, Isao; Yunus, Faisal

    2016-01-01

    Obstructive sleep apnea (OSA) is a recurrent episode of partial or complete upper airway obstruction during sleep despite ongoing respiratory efforts and is implicated as the risk factor of cardiovascular disease. The OSA syndrome is typified by recurring partial or total occlusion of the pharynx, sleep fragmentation, episodes of gasping, and, eventually, daytime sleepiness. If it is left untreated, OSA syndrome can cause hypertension, coronary artery disease congestive heart disease, insulin resistance and death. In this review, we describe the pathogenesis and diagnosis of OSA. We also focused on the continuous positive airway pressure (CPAP) as the main therapy for OSA. CPAP has been shown to provide benefit for not only respiratory system, but also for cardiovascular system and metabolic system. Finally, we discussed briefly about the issue of adherence of using CPAP that could contribute to lower compliant in patient with OSA.

  17. Unsteady flow characteristics through a human nasal airway.

    Science.gov (United States)

    Lee, Jong-Hoon; Na, Yang; Kim, Sung-Kyun; Chung, Seung-Kyu

    2010-07-31

    Time-dependent characteristics of the flow in a human nasal airway constructed from the CT image of a healthy volunteer were investigated using a computational fluid dynamics (CFD) technique. To capture the time-varying nature of the flow as well as pressure and temperature fields, the large eddy simulation (LES) technique instead of the RANS (Reynolds Averaged Navier-Stokes) approach was adopted. To make the present analysis more relevant to a real human breathing cycle, the flow was designed to be induced by the pressure difference and the time-varying pressure at the end of trachea was described to reproduce the flow rate data from the measurement. Comparison of the present results with those of typical steady simulations showed that the difference in flow characteristics is magnified in the expiration phase. This fact may suggest that the inertial effect associated with unsteady flow is more important during the expiration period. Also, the fact that the distribution of the flow rate in a given cross-section of the airway changes significantly with time implies the importance of unsteady data for clinical decision. The wall shear stress was found to have relatively high values at the locations near nasopharynx and larynx but the magnitude changes with time during the whole respiratory cycle. Analysis of the temperature field showed that most of the temperature change occurs in the nasal cavity when the air is incoming and thus, the nasal cavity acts as a very efficient heat exchanger during an inspiration period. Copyright 2010 Elsevier B.V. All rights reserved.

  18. Pressure oscillation delivery to the lung: Computer simulation of neonatal breathing parameters.

    Science.gov (United States)

    Al-Jumaily, Ahmed M; Reddy, Prasika I; Bold, Geoff T; Pillow, J Jane

    2011-10-13

    Preterm newborn infants may develop respiratory distress syndrome (RDS) due to functional and structural immaturity. A lack of surfactant promotes collapse of alveolar regions and airways such that newborns with RDS are subject to increased inspiratory effort and non-homogeneous ventilation. Pressure oscillation has been incorporated into one form of RDS treatment; however, how far it reaches various parts of the lung is still questionable. Since in-vivo measurement is very difficult if not impossible, mathematical modeling may be used as one way of assessment. Whereas many models of the respiratory system have been developed for adults, the neonatal lung remains essentially ill-described in mathematical models. A mathematical model is developed, which represents the first few generations of the tracheo-bronchial tree and the 5 lobes that make up the premature ovine lung. The elements of the model are derived using the lumped parameter approach and formulated in Simulink™ within the Matlab™ environment. The respiratory parameters at the airway opening compare well with those measured from experiments. The model demonstrates the ability to predict pressures, flows and volumes in the alveolar regions of a premature ovine lung. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Randomized trial of prongs or mask for nasal continuous positive airway pressure in preterm infants.

    LENUS (Irish Health Repository)

    Kieran, Emily A

    2012-11-01

    To determine whether nasal continuous positive airway pressure (NCPAP) given with nasal prongs compared with nasal mask reduces the rate of intubation and mechanical ventilation in preterm infants within 72 hours of starting therapy.

  20. Reduced local immune response with continuous positive airway pressure during one-lung ventilation for oesophagectomy

    NARCIS (Netherlands)

    Verhage, R. J. J.; Boone, J.; Rijkers, G. T.; Cromheecke, G. J.; Kroese, A. C.; Weijs, T. J.; Borel Rinkes, I. H. M.; van Hillegersberg, R.

    2014-01-01

    Background. Transthoracic oesophagectomy requires prolonged one-lung ventilation causing systemic and local inflammatory responses. Application of continuous positive airway pressure (CPAP) to the collapsed lung potentially reduces pulmonary damage, hypoxia, and consequent inflammation. This

  1. Imposed Work of Breathing for Flow Meters with In-Line versus Flow-Through Technique during Simulated Neonatal Breathing.

    Science.gov (United States)

    Donaldsson, Snorri; Falk, Markus; Jonsson, Baldvin; Drevhammar, Thomas

    2015-01-01

    The ability to determine airflow during nasal CPAP (NCPAP) treatment without adding dead space or resistance would be useful when investigating the physiologic effects of different NCPAP systems on breathing. The aim of this study was to investigate the effect on pressure stability of different flow measuring devices at the in-line and flow-through position, using simulated neonatal breathing. Six different flow measure devices were evaluated by recording pressure changes and imposed work of breathing for breaths with 16 and 32 ml tidal volumes. The tests were performed initially with the devices in an in line position and with 5 and 10 L/min using flow through technique, without CPAP. The flow meters were then subsequently tested with an Infant Flow CPAP system at 3, 5 and 8 cm H2O pressure using flow through technique. The quality of the recorded signals was compared graphically. The resistance of the measuring devices generated pressure swings and imposed work of breathing. With bias flow, the resistance also generated CPAP pressure. Three of the devices had low resistance and generated no changes in pressure stability or CPAP pressure. The two devices intended for neonatal use had the highest measured resistance. The importance of pressure stability and increased work of breathing during non-invasive respiratory support are insufficiently studied. Clinical trials using flow-through technique have not focused on pressure stability. Our results indicate that a flow-through technique might be a way forward in obtaining a sufficiently high signal quality without the added effects of rebreathing and increased work of breathing. The results should stimulate further research and the development of equipment for dynamic flow measurements in neonates.

  2. Choosing an Oronasal Mask to Deliver Continuous Positive Airway Pressure May Cause More Upper Airway Obstruction or Lead to Higher Continuous Positive Airway Pressure Requirements than a Nasal Mask in Some Patients: A Case Series.

    Science.gov (United States)

    Ng, Justin R; Aiyappan, Vinod; Mercer, Jeremy; Catcheside, Peter G; Chai-Coetzer, Ching Li; McEvoy, R Doug; Antic, Nick

    2016-09-15

    The choice of mask interface used with continuous positive airway pressure (CPAP) therapy can affect the control of upper airway obstruction (UAO) in obstructive sleep apnea (OSA). We describe a case series of four patients with paradoxical worsening of UAO with an oronasal mask and the effect of changing to a nasal mask. We retrospectively reviewed the case histories of 4 patients and recorded patient demographics, in-laboratory and ambulatory CPAP titration data, CPAP therapy data, type of mask interface used and potential confounding factors. The 4 cases (mean ± SD: age = 59 ± 16 y; BMI = 30.5 ± 4.5 kg/m(2)) had a high residual apnoea-hypopnea index (AHI) (43 ± 14.2 events/h) and high CPAP pressure requirements (14.9 ± 6.6 cmH2O) with an oronasal mask. Changing to a nasal mask allowed adequate control of UAO with a significant reduction in the average residual AHI (3.1 ± 1.5 events/h). In two of the four cases, it was demonstrated that control of UAO was obtained at a much lower CPAP pressure compared to the oronasal mask (Case one = 17.5 cmH2O vs 12cmH2O; Case two = 17.9 cmH2O vs 7.8 cmH2O). Other potential confounding factors were unchanged. There are various physiological observations that may explain these findings but it is uncertain which individuals are susceptible to these mechanisms. If patients have OSA incompletely controlled by CPAP with evidence of residual UAO and/or are requiring surprisingly high CPAP pressure to control OSA with an oronasal mask, the choice of mask should be reviewed and consideration be given to a trial of a nasal mask. A commentary on this article appears in this issue on page 1209. © 2016 American Academy of Sleep Medicine.

  3. Continuous Positive Airway Pressure for Motion Management in Stereotactic Body Radiation Therapy to the Lung: A Controlled Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, Jeffrey D. [Department of Radiation Oncology, Chaim Sheba Medical Center, Tel Hashomer, Tel Aviv (Israel); Lawrence, Yaacov R. [Department of Radiation Oncology, Chaim Sheba Medical Center, Tel Hashomer, Tel Aviv (Israel); Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Appel, Sarit; Landau, Efrat; Ben-David, Merav A.; Rabin, Tatiana; Benayun, Maoz; Dubinski, Sergey; Weizman, Noam; Alezra, Dror; Gnessin, Hila; Goldstein, Adam M.; Baidun, Khader [Department of Radiation Oncology, Chaim Sheba Medical Center, Tel Hashomer, Tel Aviv (Israel); Segel, Michael J.; Peled, Nir [Department of Pulmonary Medicine, Chaim Sheba Medical Center, Tel Hashomer, Tel Aviv (Israel); Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Symon, Zvi, E-mail: symonz@sheba.health.gov.il [Department of Radiation Oncology, Chaim Sheba Medical Center, Tel Hashomer, Tel Aviv (Israel); Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel)

    2015-10-01

    Objective: To determine the effect of continuous positive airway pressure (CPAP) on tumor motion, lung volume, and dose to critical organs in patients receiving stereotactic body radiation therapy (SBRT) for lung tumors. Methods and Materials: After institutional review board approval in December 2013, patients with primary or secondary lung tumors referred for SBRT underwent 4-dimensional computed tomographic simulation twice: with free breathing and with CPAP. Tumor excursion was calculated by subtracting the vector of the greatest dimension of the gross tumor volume (GTV) from the internal target volume (ITV). Volumetric and dosimetric determinations were compared with the Wilcoxon signed-rank test. CPAP was used during treatment if judged beneficial. Results: CPAP was tolerated well in 10 of the 11 patients enrolled. Ten patients with 18 lesions were evaluated. The use of CPAP decreased tumor excursion by 0.5 ± 0.8 cm, 0.4 ± 0.7 cm, and 0.6 ± 0.8 cm in the superior–inferior, right–left, and anterior–posterior planes, respectively (P≤.02). Relative to free breathing, the mean ITV reduction was 27% (95% confidence interval [CI] 16%-39%, P<.001). CPAP significantly augmented lung volume, with a mean absolute increase of 915 ± 432 cm{sup 3} and a relative increase of 32% (95% CI 21%-42%, P=.003), contributing to a 22% relative reduction (95% CI 13%-32%, P=.001) in mean lung dose. The use of CPAP was also associated with a relative reduction in mean heart dose by 29% (95% CI 23%-36%, P=.001). Conclusion: In this pilot study, CPAP significantly reduced lung tumor motion compared with free breathing. The smaller ITV, the planning target volume (PTV), and the increase in total lung volume associated with CPAP contributed to a reduction in lung and heart dose. CPAP was well tolerated, reproducible, and simple to implement in the treatment room and should be evaluated further as a novel strategy for motion management in radiation therapy.

  4. Continuous Positive Airway Pressure for Motion Management in Stereotactic Body Radiation Therapy to the Lung: A Controlled Pilot Study

    International Nuclear Information System (INIS)

    Goldstein, Jeffrey D.; Lawrence, Yaacov R.; Appel, Sarit; Landau, Efrat; Ben-David, Merav A.; Rabin, Tatiana; Benayun, Maoz; Dubinski, Sergey; Weizman, Noam; Alezra, Dror; Gnessin, Hila; Goldstein, Adam M.; Baidun, Khader; Segel, Michael J.; Peled, Nir; Symon, Zvi

    2015-01-01

    Objective: To determine the effect of continuous positive airway pressure (CPAP) on tumor motion, lung volume, and dose to critical organs in patients receiving stereotactic body radiation therapy (SBRT) for lung tumors. Methods and Materials: After institutional review board approval in December 2013, patients with primary or secondary lung tumors referred for SBRT underwent 4-dimensional computed tomographic simulation twice: with free breathing and with CPAP. Tumor excursion was calculated by subtracting the vector of the greatest dimension of the gross tumor volume (GTV) from the internal target volume (ITV). Volumetric and dosimetric determinations were compared with the Wilcoxon signed-rank test. CPAP was used during treatment if judged beneficial. Results: CPAP was tolerated well in 10 of the 11 patients enrolled. Ten patients with 18 lesions were evaluated. The use of CPAP decreased tumor excursion by 0.5 ± 0.8 cm, 0.4 ± 0.7 cm, and 0.6 ± 0.8 cm in the superior–inferior, right–left, and anterior–posterior planes, respectively (P≤.02). Relative to free breathing, the mean ITV reduction was 27% (95% confidence interval [CI] 16%-39%, P<.001). CPAP significantly augmented lung volume, with a mean absolute increase of 915 ± 432 cm 3 and a relative increase of 32% (95% CI 21%-42%, P=.003), contributing to a 22% relative reduction (95% CI 13%-32%, P=.001) in mean lung dose. The use of CPAP was also associated with a relative reduction in mean heart dose by 29% (95% CI 23%-36%, P=.001). Conclusion: In this pilot study, CPAP significantly reduced lung tumor motion compared with free breathing. The smaller ITV, the planning target volume (PTV), and the increase in total lung volume associated with CPAP contributed to a reduction in lung and heart dose. CPAP was well tolerated, reproducible, and simple to implement in the treatment room and should be evaluated further as a novel strategy for motion management in radiation therapy

  5. The effects of breath-holding on pulmonary regurgitation measured by cardiovascular magnetic resonance velocity mapping

    Directory of Open Access Journals (Sweden)

    Babu-Narayan Sonya V

    2009-01-01

    Full Text Available Abstract Background Pulmonary regurgitation is a common and clinically important residual lesion after repair of tetralogy of Fallot. Cardiovascular magnetic resonance (CMR phase contrast velocity mapping is widely used for measurement of pulmonary regurgitant fraction. Breath-hold acquisitions, usually acquired during held expiration, are more convenient than the non-breath-hold approach, but we hypothesized that breath-holding might affect the amount of pulmonary regurgitation. Methods Forty-three adult patients with a previous repair of tetralogy of Fallot and residual pulmonary regurgitation were investigated with CMR. In each, pulmonary regurgitant fraction was measured from velocity maps transecting the pulmonary trunk, acquired during held expiration, held inspiration, by non-breath-hold acquisition, and also from the difference of right and left ventricular stroke volume measurements. Results Pulmonary regurgitant fraction was lower when measured by velocity mapping in held expiration compared with held inspiration, non-breath-hold or stroke volume difference (30.8 vs. 37.0, 35.6, 35.4%, p = 0.00017, 0.0035, 0.026. The regurgitant volume was lower in held expiration than in held inspiration (41.9 vs. 48.3, p = 0.0018. Pulmonary forward flow volume was larger during held expiration than during non-breath-hold (132 vs. 124 ml, p = 0.0024. Conclusion Pulmonary regurgitant fraction was significantly lower in held expiration compared with held inspiration, free breathing and stroke volume difference. Altered airway pressure could be a contributory factor. This information is relevant if breath-hold acquisition is to be substituted for non-breath-hold in the investigation of patients with a view to re-intervention.

  6. Imposed Work of Breathing for Flow Meters with In-Line versus Flow-Through Technique during Simulated Neonatal Breathing.

    Directory of Open Access Journals (Sweden)

    Snorri Donaldsson

    Full Text Available The ability to determine airflow during nasal CPAP (NCPAP treatment without adding dead space or resistance would be useful when investigating the physiologic effects of different NCPAP systems on breathing. The aim of this study was to investigate the effect on pressure stability of different flow measuring devices at the in-line and flow-through position, using simulated neonatal breathing.Six different flow measure devices were evaluated by recording pressure changes and imposed work of breathing for breaths with 16 and 32 ml tidal volumes. The tests were performed initially with the devices in an in line position and with 5 and 10 L/min using flow through technique, without CPAP. The flow meters were then subsequently tested with an Infant Flow CPAP system at 3, 5 and 8 cm H2O pressure using flow through technique. The quality of the recorded signals was compared graphically.The resistance of the measuring devices generated pressure swings and imposed work of breathing. With bias flow, the resistance also generated CPAP pressure. Three of the devices had low resistance and generated no changes in pressure stability or CPAP pressure. The two devices intended for neonatal use had the highest measured resistance.The importance of pressure stability and increased work of breathing during non-invasive respiratory support are insufficiently studied. Clinical trials using flow-through technique have not focused on pressure stability. Our results indicate that a flow-through technique might be a way forward in obtaining a sufficiently high signal quality without the added effects of rebreathing and increased work of breathing. The results should stimulate further research and the development of equipment for dynamic flow measurements in neonates.

  7. Numerical investigation of inspiratory airflow in a realistic model of the human tracheobronchial airways and a comparison with experimental results.

    Science.gov (United States)

    Elcner, Jakub; Lizal, Frantisek; Jedelsky, Jan; Jicha, Miroslav; Chovancova, Michaela

    2016-04-01

    In this article, the results of numerical simulations using computational fluid dynamics (CFD) and a comparison with experiments performed with phase Doppler anemometry are presented. The simulations and experiments were conducted in a realistic model of the human airways, which comprised the throat, trachea and tracheobronchial tree up to the fourth generation. A full inspiration/expiration breathing cycle was used with tidal volumes 0.5 and 1 L, which correspond to a sedentary regime and deep breath, respectively. The length of the entire breathing cycle was 4 s, with inspiration and expiration each lasting 2 s. As a boundary condition for the CFD simulations, experimentally obtained flow rate distribution in 10 terminal airways was used with zero pressure resistance at the throat inlet. CCM+ CFD code (Adapco) was used with an SST k-ω low-Reynolds Number RANS model. The total number of polyhedral control volumes was 2.6 million with a time step of 0.001 s. Comparisons were made at several points in eight cross sections selected according to experiments in the trachea and the left and right bronchi. The results agree well with experiments involving the oscillation (temporal relocation) of flow structures in the majority of the cross sections and individual local positions. Velocity field simulation in several cross sections shows a very unstable flow field, which originates in the tracheal laryngeal jet and propagates far downstream with the formation of separation zones in both left and right airways. The RANS simulation agrees with the experiments in almost all the cross sections and shows unstable local flow structures and a quantitatively acceptable solution for the time-averaged flow field.

  8. Continuous Positive Airway Pressure Prevents Hypoxia in Dental Patient with Obstructive Sleep Apnea Syndrome under Intravenous Sedation.

    Science.gov (United States)

    Kasatkin, Anton A; Reshetnikov, Aleksei P; Urakov, Aleksandr L; Baimurzin, Dmitrii Y

    2017-01-01

    Use of sedation in patients with obstructive sleep apnea (OSA) in dentistry is limited. Hypoxia may develop during medication sleep in dental patients with OSA because of repetitive partial or complete obstruction of the upper airway. In this regard, anesthesiologists prefer not to give any sedative to surgical patients with OSA or support the use of general anesthesia due to good airway control. We report a case where we could successfully sedate a dental patient with OSA using intraoperative continuous positive airway pressure (CPAP) without hypoxia. Use of sedation and intraoperative CPAP in patients with OSA may be considered only if the effectiveness at home CPAP therapy is proven.

  9. Ultrafast CT in the diagnosis of sleep apnea during awake tidal breathing

    International Nuclear Information System (INIS)

    Galvin, J.R.; Rooholamini, S.A.; Stanford, W.

    1988-01-01

    With sleep there is normally a decrease in neural output to upper airway muscles. If this decrease is superimposed on a structurally abnormal airway, then sleep apnea may result. Ultrafast CT axially images the upper airway in near real time. The authors compared 11 awake patients with sleep apnea with 24 healthy volunteers during quiet tidal breathing. They found that apneic patients have a small oropharyngeal airway (31.3 mm 2 +- 30.2 vs 134.2 mm 2 +- 46.6[P=<.0001]). Apneic patients also have significant collapsibility of the nasopharynx (75% +- 18% vs 27% +- 14% [P=<.0001]). Ultrafast CT gives dynamic anatomic definition of the upper airway and provides a means to eulcidate further the pathogenesis of sleep apnea

  10. Clinical predictors of central sleep apnea evoked by positive airway pressure titration

    Directory of Open Access Journals (Sweden)

    Moro M

    2016-07-01

    Full Text Available Marilyn Moro,1 Karen Gannon,1 Kathy Lovell,1 Margaret Merlino,1 James Mojica,2 Matt T Bianchi,1,3 1Neurology Department, 2Pulmonary and Critical Care Medicine, Massachusetts General Hospital, Boston, MA, USA; 3Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA Purpose: Treatment-emergent central sleep apnea (TECSA, also called complex apnea, occurs in 5%–15% of sleep apnea patients during positive airway pressure (PAP therapy, but the clinical predictors are not well understood. The goal of this study was to explore possible predictors in a clinical sleep laboratory cohort, which may highlight those at risk during clinical management.Methods: We retrospectively analyzed 728 patients who underwent PAP titration (n=422 split night; n=306 two-night. Demographics and self-reported medical comorbidities, medications, and behaviors as well as standard physiological parameters from the polysomnography (PSG data were analyzed. We used regression analysis to assess predictors of binary presence or absence of central apnea index (CAI ≥5 during split PSG (SN-PSG versus full-night PSG (FN-PSG titrations.Results: CAI ≥5 was present in 24.2% of SN-PSG and 11.4% of FN-PSG patients during titration. Male sex, maximum continuous positive airway pressure, and use of bilevel positive airway pressure were predictors of TECSA, and rapid eye movement dominance was a negative predictor, for both SN-PSG and FN-PSG patients. Self-reported narcotics were a positive predictor of TECSA, and the time spent in stage N2 sleep was a negative predictor only for SN-PSG patients. Self-reported history of stroke and the CAI during the diagnostic recording predicted TECSA only for FN-PSG patients.Conclusion: Clinical predictors of treatment-evoked central apnea spanned demographic, medical history, sleep physiology, and titration factors. Improved predictive models may be increasingly important as diagnostic and therapeutic modalities move away from the

  11. The impact of dysfunctional breathing on the assessment of asthma control

    DEFF Research Database (Denmark)

    Veidal, Sandra; Jeppegaard, Maria; Sverrild, Asger

    2017-01-01

    asthma control compared to asthmatics without DB (Median (range) ACQ score: 2.40 (0.20-4.60) vs 1.20 (0.00-4.40); p asthma control was independent of airway hyperresponsiveness or airway inflammation in patients with DB. CONCLUSION......BACKGROUND AND OBJECTIVE: Dysfunctional breathing (DB) is a respiratory disorder, which involves a pattern of breathing too deeply, too superficially and/or too rapidly. In asthma patients, DB may lead to an overestimation of the severity of asthma symptoms, and hence potentially to overtreatment....... However, it is not known to which degree DB may affect estimates of asthma control, in a specialist clinical setting. METHODS: The MAPOut-study examined all patients referred consecutively over a 12-months period for specialist assessment of asthma at the Respiratory Outpatient Clinic at Bispebjerg...

  12. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Physical Therapy Coughing and Huffing High-Frequency Chest Wall Oscillation Positive Expiratory Pressure Clinical Trials Clinical Trials ... clapping) or vibration to loosen mucus from airway walls. See how different airway clearance techniques work to ...

  13. Radial breathing vibration of double-walled carbon nanotubes subjected to pressure

    International Nuclear Information System (INIS)

    Lei, Xiao-Wen; Natsuki, Toshiaki; Shi, Jin-Xing; Ni, Qing-Qing

    2011-01-01

    A theoretical vibrational analysis of the radial breathing mode (RBM) of double-walled carbon nanotubes (DWCNTs) subjected to pressure is presented based on an elastic continuum model. The results agree with reported experimental results obtained under different conditions. Frequencies of the RBM in DWCNTs subjected to increasing pressure depend strongly on circumferential wave numbers, but weakly on the aspect ratio and axial half-wave numbers. For the inner and outer tubes of DWCNTs, the frequency of the RBM increases obviously as the pressure increases under different conditions. The range of variation is smaller for the inner tube than the outer tube. -- Highlights: → An elastic continuum model is used in the theoretical analysis of RBM of DWCNTs. → The RBM of DWCNTs subjected to pressure is analyzed. → Frequency of RBM depends on wave number and aspect ratio. → Frequencies of RBM in inner and outer tubes change in different trends and ranges.

  14. Bronchoscopic lung-volume reduction with Exhale airway stents for emphysema (EASE trial) : randomised, sham-controlled, multicentre trial

    NARCIS (Netherlands)

    Shah, P. L.; Slebos, D-J; Cardoso, P. F. G.; Cetti, E.; Voelker, K.; Levine, B.; Russell, M. E.; Goldin, J.; Brown, M.; Cooper, J. D.; Sybrecht, G. W.

    2011-01-01

    Background Airway bypass is a bronchoscopic lung-volume reduction procedure for emphysema whereby transbronchial passages into the lung are created to release trapped air, supported with paclitaxel-coated stents to ease the mechanics of breathing. The aim of the EASE (Exhale airway stents for

  15. Nasal continuous positive airways pressure immediately after extubation for preventing morbidity in preterm infants.

    Science.gov (United States)

    Davis, P G; Henderson-Smart, D J

    2003-01-01

    Preterm infants being extubated following a period of intermittent positive pressure ventilation via an endotracheal tube are at risk of developing respiratory failure as a result of apnea, respiratory acidosis and hypoxia. Nasal continuous positive airway pressure appears to stabilise the upper airway, improve lung function and reduce apnea and may therefore have a role in facilitating extubation in this population. In preterm infants having their endotracheal tube removed following a period of intermittent positive pressure ventilation (IPPV), does management with nasal continuous positive airways pressure (NCPAP) lead to an increased proportion remaining free of additional ventilatory support, compared to extubation directly to headbox oxygen? Searches were made of the Oxford Database of Perinatal Trials, MEDLINE up to November 2002, Cochrane Controlled Trials Register (The Cochrane Library, Issue 4, 2002), previous reviews including cross references, abstracts of conferences and symposia proceedings, expert informants and journal handsearching mainly in the English language. All trials utilising random or quasi-random patient allocation, in which NCPAP (delivered by any method) was compared with headbox oxygen for post-extubation care were included. Methodological quality was assessed independently by the two authors. Data were extracted independently by the two authors. Prespecified subgroup analysis to determine the impact of different levels of NCPAP, differences in duration of IPPV and use of aminophylline were also performed using the same package. Data were analysed using relative risk (RR), risk difference (RD) and number needed to treat (NNT). Nasal CPAP, when applied to preterm infants being extubated following IPPV, reduces the incidence of adverse clinical events (apnea, respiratory acidosis and increased oxygen requirements) indicating the need for additional ventilatory support [RR 0.62 (0.49, 0.77), RD -0.17 (-0.24,-0.10), NNT 6 (4,10)]. nasal

  16. Impact of varying physical activity levels on airway sensitivity and bronchodilation in healthy humans.

    Science.gov (United States)

    Smith, Joshua R; Kurti, Stephanie P; Johnson, Ariel M; Kolmer, Sarah A; Harms, Craig

    2015-12-01

    The purpose of this study was to determine if the amount of physical activity influences airway sensitivity and bronchodilation in healthy subjects across a range of physical activity levels. Thirty healthy subjects (age, 21.9 ± 2.6 years; 13 men/17 women) with normal pulmonary function reported to the laboratory on 2 separate occasions where they were randomized to breathe either hypertonic saline (HS) (nebulized hypertonic saline (25%) for 20 min) or HS followed by 5 deep inspirations (DIs), which has been reported to bronchodilate the airways. Pulmonary function tests (PFTs) were performed prior to both conditions and following the HS breathing or 5 DIs. Moderate to vigorous physical activity (MVPA) level was measured via accelerometer worn for 7 days. Following the HS breathing, forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) significantly decreased from baseline by -11.8% ± 8.4% and -9.3% ± 6.7%, respectively. A 2-segment linear model determined significant relationships between MVPA and percent change in FEV1 (r = 0.50) and FVC (r = 0.55). MVPA above ∼497 and ∼500 min/week for FEV1 and FVC, respectively, resulted in minor additional improvements (p > 0.05) in PFTs following the HS breathing. Following the DIs, FEV1 and FVC decreased (p 0.05) to MVPA. In conclusion, these data demonstrate that higher MVPA levels attenuated airway sensitivity but not bronchodilation in healthy subjects.

  17. Computationally efficient analysis of particle transport and deposition in a human whole-lung-airway model. Part I: Theory and model validation.

    Science.gov (United States)

    Kolanjiyil, Arun V; Kleinstreuer, Clement

    2016-12-01

    Computational predictions of aerosol transport and deposition in the human respiratory tract can assist in evaluating detrimental or therapeutic health effects when inhaling toxic particles or administering drugs. However, the sheer complexity of the human lung, featuring a total of 16 million tubular airways, prohibits detailed computer simulations of the fluid-particle dynamics for the entire respiratory system. Thus, in order to obtain useful and efficient particle deposition results, an alternative modeling approach is necessary where the whole-lung geometry is approximated and physiological boundary conditions are implemented to simulate breathing. In Part I, the present new whole-lung-airway model (WLAM) represents the actual lung geometry via a basic 3-D mouth-to-trachea configuration while all subsequent airways are lumped together, i.e., reduced to an exponentially expanding 1-D conduit. The diameter for each generation of the 1-D extension can be obtained on a subject-specific basis from the calculated total volume which represents each generation of the individual. The alveolar volume was added based on the approximate number of alveoli per generation. A wall-displacement boundary condition was applied at the bottom surface of the first-generation WLAM, so that any breathing pattern due to the negative alveolar pressure can be reproduced. Specifically, different inhalation/exhalation scenarios (rest, exercise, etc.) were implemented by controlling the wall/mesh displacements to simulate realistic breathing cycles in the WLAM. Total and regional particle deposition results agree with experimental lung deposition results. The outcomes provide critical insight to and quantitative results of aerosol deposition in human whole-lung airways with modest computational resources. Hence, the WLAM can be used in analyzing human exposure to toxic particulate matter or it can assist in estimating pharmacological effects of administered drug-aerosols. As a practical

  18. Simulated driving in obstructive sleep apnoea-hypopnoea : effects of oral appliances and continuous positive airway pressure

    NARCIS (Netherlands)

    Hoekema, Aarnoud; Stegenga, Boudewijn; Bakker, Marije; Brouwer, Wiebo H.; de Bont, Lambert G. M.; Wijkstra, Peter J.; van der Hoeven, Johannes H.

    Impaired simulated driving performance has been demonstrated in obstructive sleep apnoea-hypopnoea syndrome (OSAHS) patients. Although continuous positive airway pressure (CPAP) generally improves simulated driving performance, the effects of oral-appliance (OA) therapy are unknown. The aims of this

  19. Upper Airway Volume Segmentation Analysis Using Cine MRI Findings in Children with Tracheostomy Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, Bradley L.; Abbott, M. Bret; Donnelly, Lane F.; Dardzinski, Bernard J.; Poe, Stacy A.; Kalra, Maninder; Amin, Raouf S.; Cotton, Robin T. [Cincinnati Children' s Hospital Medical Center, Cincinnati (United States)

    2007-12-15

    The purpose of this study is to evaluate the airway dynamics of the upper airway as depicted on cine MRI in children with tracheotomy tubes during two states of airflow through the upper airway. Sagittal fast gradient echo cine MR images of the supra-glottic airway were obtained with a 1.5T MRI scanner on seven children with tracheotomy tubes. Two sets of images were obtained with either the tubes capped or uncapped. The findings of the cine MRI were retrospectively reviewed. Volume segmentation of the cine images to compare the airway volume change over time (mean volume, standard deviation, normalized range, and coefficient of variance) was performed for the capped and uncapped tubes in both the nasopharynx and hypopharynx (Signed Rank Test). Graphical representation of the airway volume over time demonstrates a qualitative increased fluctuation in patients with the tracheotomy tube capped as compared to uncapped in both the nasopharyngeal and hypopharyngeal regions of interest. In the nasopharynx, the mean airway volume (capped 2.72 mL, uncapped 2.09 mL, p = 0.0313), the airway volume standard deviation (capped 0.42 mL, uncapped 0.20 mL, p = 0.0156), and the airway volume range (capped 2.10 mL, uncapped 1.09 mL, p = 0.0156) were significantly larger in the capped group of patients. In the hypopharynx, the airway volume standard deviation (capped 1.54 mL, uncapped 0.67 mL, p = 0.0156), and the airway volume range (capped 6.44 mL, uncapped 2.93 mL, p = 0.0156) were significantly larger in the capped tubes. The coefficient of variance (capped 0.37, uncapped 0.26, p = 0.0469) and the normalized range (capped 1.52, uncapped 1.09, p = 0.0313) were significantly larger in the capped tubes. There is a statistically significant change in airway dynamics in children with tracheotomy tubes when breathing via the airway as compared to breathing via the tracheotomy tube.

  20. Upper Airway Volume Segmentation Analysis Using Cine MRI Findings in Children with Tracheostomy Tubes

    International Nuclear Information System (INIS)

    Fricke, Bradley L.; Abbott, M. Bret; Donnelly, Lane F.; Dardzinski, Bernard J.; Poe, Stacy A.; Kalra, Maninder; Amin, Raouf S.; Cotton, Robin T.

    2007-01-01

    The purpose of this study is to evaluate the airway dynamics of the upper airway as depicted on cine MRI in children with tracheotomy tubes during two states of airflow through the upper airway. Sagittal fast gradient echo cine MR images of the supra-glottic airway were obtained with a 1.5T MRI scanner on seven children with tracheotomy tubes. Two sets of images were obtained with either the tubes capped or uncapped. The findings of the cine MRI were retrospectively reviewed. Volume segmentation of the cine images to compare the airway volume change over time (mean volume, standard deviation, normalized range, and coefficient of variance) was performed for the capped and uncapped tubes in both the nasopharynx and hypopharynx (Signed Rank Test). Graphical representation of the airway volume over time demonstrates a qualitative increased fluctuation in patients with the tracheotomy tube capped as compared to uncapped in both the nasopharyngeal and hypopharyngeal regions of interest. In the nasopharynx, the mean airway volume (capped 2.72 mL, uncapped 2.09 mL, p = 0.0313), the airway volume standard deviation (capped 0.42 mL, uncapped 0.20 mL, p = 0.0156), and the airway volume range (capped 2.10 mL, uncapped 1.09 mL, p = 0.0156) were significantly larger in the capped group of patients. In the hypopharynx, the airway volume standard deviation (capped 1.54 mL, uncapped 0.67 mL, p = 0.0156), and the airway volume range (capped 6.44 mL, uncapped 2.93 mL, p = 0.0156) were significantly larger in the capped tubes. The coefficient of variance (capped 0.37, uncapped 0.26, p = 0.0469) and the normalized range (capped 1.52, uncapped 1.09, p = 0.0313) were significantly larger in the capped tubes. There is a statistically significant change in airway dynamics in children with tracheotomy tubes when breathing via the airway as compared to breathing via the tracheotomy tube

  1. Continuous positive airway pressure with helmet versus mask in infants with bronchiolitis: an RCT.

    Science.gov (United States)

    Chidini, Giovanna; Piastra, Marco; Marchesi, Tiziana; De Luca, Daniele; Napolitano, Luisa; Salvo, Ida; Wolfler, Andrea; Pelosi, Paolo; Damasco, Mirco; Conti, Giorgio; Calderini, Edoardo

    2015-04-01

    Noninvasive continuous positive airway pressure (CPAP) is usually applied with a nasal or facial mask to treat mild acute respiratory failure (ARF) in infants. A pediatric helmet has now been introduced in clinical practice to deliver CPAP. This study compared treatment failure rates during CPAP delivered by helmet or facial mask in infants with respiratory syncytial virus-induced ARF. In this multicenter randomized controlled trial, 30 infants with respiratory syncytial virus-induced ARF were randomized to receive CPAP by helmet (n = 17) or facial mask (n = 13). The primary endpoint was treatment failure rate (defined as due to intolerance or need for intubation). Secondary outcomes were CPAP application time, number of patients requiring sedation, and complications with each interface. Compared with the facial mask, CPAP by helmet had a lower treatment failure rate due to intolerance (3/17 [17%] vs 7/13 [54%], P = .009), and fewer infants required sedation (6/17 [35%] vs 13/13 [100%], P = .023); the intubation rates were similar. In successfully treated patients, CPAP resulted in better gas exchange and breathing pattern with both interfaces. No major complications due to the interfaces occurred, but CPAP by mask had higher rates of cutaneous sores and leaks. These findings confirm that CPAP delivered by helmet is better tolerated than CPAP delivered by facial mask and requires less sedation. In addition, it is safe to use and free from adverse events, even in a prolonged clinical setting. Copyright © 2015 by the American Academy of Pediatrics.

  2. Clinical predictors of central sleep apnea evoked by positive airway pressure titration

    OpenAIRE

    Bianchi, Matt; Gannon,Karen; Lovell,Kathy; Merlino,Margaret; Mojica,James; Moro,Marilyn

    2016-01-01

    Marilyn Moro,1 Karen Gannon,1 Kathy Lovell,1 Margaret Merlino,1 James Mojica,2 Matt T Bianchi,1,3 1Neurology Department, 2Pulmonary and Critical Care Medicine, Massachusetts General Hospital, Boston, MA, USA; 3Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA Purpose: Treatment-emergent central sleep apnea (TECSA), also called complex apnea, occurs in 5%–15% of sleep apnea patients during positive airway pressure (PAP) therapy, but the clinical predictors are not w...

  3. A comparison between the v-gel supraglottic airway device and the cuffed endotracheal tube for airway management in spontaneously breathing cats during isoflurane anaesthesia

    NARCIS (Netherlands)

    van Oostrom, H.; Krauss, M.W.; Sap, R.

    2013-01-01

    Abstract OBJECTIVE: To compare airway management using the v-gel supraglottic airway device (v-gel SGAD) to that using an endotracheal tube (ETT), with respect to practicability, leakage of volatile anaesthetics and upper airway discomfort in cats. STUDY DESIGN: Prospective, randomized clinical

  4. A fibre-optic oxygen sensor for monitoring human breathing

    International Nuclear Information System (INIS)

    Chen, Rongsheng; Formenti, Federico; Hahn, Clive E W; Farmery, Andrew D; Obeid, Andy

    2013-01-01

    The development and construction of a tapered-tip fibre-optic fluorescence based oxygen sensor is described. The sensor is suitable for fast and real-time monitoring of human breathing. The sensitivity and response time of the oxygen sensor were evaluated in vitro with a gas pressure chamber system, where oxygen partial pressure was rapidly changed between 5 and 15 kPa, and then in vivo in five healthy adult participants who synchronized their breathing to a metronome set at 10, 20, 30, 40, 50, and 60 breaths min –1 . A Datex Ultima medical gas analyser was used to monitor breathing rate as a comparator. The sensor's response time in vitro was less than 150 ms, which allows accurate continuous measurement of inspired and expired oxygen pressure. Measurements of breathing rate by means of our oxygen sensor and of the Datex Ultima were in strong agreement. The results demonstrate that the device can reliably resolve breathing rates up to 60 breaths min –1 , and that it is a suitable cost-effective alternative for monitoring breathing rates and end-tidal oxygen partial pressure in the clinical setting. The rapid response time of the sensor may allow its use for monitoring rapid breathing rates as occur in children and the newborn. (note)

  5. Construction of an Anthropomorphic Phantom for Use in Evaluating Pediatric Airway Digital Tomosynthesis Protocols

    Directory of Open Access Journals (Sweden)

    Nima Kasraie

    2018-01-01

    Full Text Available Interpretation of radiolucent foreign bodies (FBs is a common task charged to pediatric radiologists. The use of a motion compensated technique to decrease breathing motion on images would greatly decrease overall exposure to ionizing radiation and increase access to treatment yielding a great impact on clinical care. This study reports on the methodology and materials used to construct an in-house anthropomorphic phantom for investigating image quality in digital tomosynthesis protocols for volumetric imaging of the pediatric airway. Availability and cost of possible substitute materials were considered and simplifying assumptions were made. Two different modular phantoms were assembled in coronal slab layers using materials designed to approximate a one- and three-year-old thorax at diagnostic photon energies for use with digital tomosynthesis protocols such as those offered on GE’s VolumeRAD application. Exposures were made using both phantoms with inserted food particles inside an oscillating airway. The goal of the phantom is to help evaluate (1 whether the currently used protocol is sufficient to image the airway despite breathing motion and (2 whether it is not, to find the optimal protocol by testing various commercially available protocols using this phantom. The affordable construction of the pediatric sized phantom aimed at optimizing GE’s VolumeRAD protocol for airway foreign body imaging is demonstrated in this study which can be used to test VolumeRAD’s ability to image the airways with and without a low-density foreign body within the airways.

  6. Effect of upper airway CO2 pattern on ventilatory frequency in tegu lizards.

    Science.gov (United States)

    Ballam, G O; Coates, E L

    1989-07-01

    Nasal CO2-sensitive receptors are reported to depress ventilatory frequency in several reptilian species in response to constant low levels of inspired CO2. The purpose of this study was to determine the influence of phasic patterns of CO2 in the upper airways on ventilation. Awake lizards (Tupinambis nigropunctatus) breathed through an endotracheal tube from an isolated gas source. A second gas mixture was forced at constant flow into the external nares. A concentration of 4% CO2 was intermittently pulsed through the nares in a square-wave pattern with a frequency of 60, 12, 6, 4.2, 1.8, and 0.6 cycles/min. Concentrations of 2, 3, 4, and 6% CO2 were also pulsed through the nares at 12 cycles/min and compared with sustained levels of 1, 1.5, 2, and 3%. Additionally, 0 or 3% CO2 was forced through the upper airways with a servo system designed to mimic normal ventilatory flow and gas concentrations. No changes in breathing pattern were noted during any of the pulsing protocols, although a significant breathing frequency depression was present with sustained levels of CO2 of comparable mean concentrations. We conclude that ventilatory control is selectively responsive to sustained levels of environmental CO2 but not to phasic changes in upper airway CO2 concentration.

  7. Dimensions of the cleft nasal airway in adults: a comparison with subjects without cleft.

    Science.gov (United States)

    Hairfield, W M; Warren, D W

    1989-01-01

    The prevalence of mouthbreathing among individuals with cleft lip and palate is significantly higher than in the normal population. This has been attributed to nasal deformities that tend to reduce nasal airway size. The purpose of the present study was to determine how a heterogeneous adult group with cleft lip and palate differs in terms of nasal airway cross-sectional area from an adult group without cleft during the inspiratory and expiratory phases of breathing. The pressure-flow technique was used to estimate nasal airway size in 15 adults without cleft (15 years or older) and 37 adults with cleft lip, cleft palate, or both. Mean areas and standard deviations for subjects without cleft were 0.63 cm2 +/- 0.17 during inspiration and 0.56 cm2 +/- 0.14 during expiration. This difference is statistically significant (p less than 0.01). Mean areas and standard deviations for all subjects with cleft were 0.37 cm2 +/- 0.18 during inspiration and 0.40 cm2 +/- 0.20 during expiration. This difference is not statistically significant (p greater than 0.15). Twenty-two of the subjects with cleft had nasal areas considered to be impaired (below 0.40 cm2) as compared with only three of the subjects without cleft. A two factor analysis of variance (ANOVA) demonstrated that area changes during respiration are different for subjects with and without cleft (p less than 0.005), and that cleft nasal areas are smaller than noncleft areas for both phases of breathing (p less than 0.001). Inspiratory-expiratory differences between subjects with and without cleft are probably the result of developmental defects, reparative surgery or both.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Postoperative environmental anesthetic vapour concentrations following removal of the airway device in the operating room versus the postanesthesia care unit.

    Science.gov (United States)

    Cheung, Sara K; Özelsel, Timur; Rashiq, Saifee; Tsui, Ban C

    2016-09-01

    This study was designed to compare waste anesthetic gas (WAG) concentrations within patients' breathing zones after removal of the patient's airway device in the postanesthesia care unit (PACU) vs in the operating room (OR). Following Research Ethics Board approval and patient consent, we recruited patients undergoing surgery who received volatile anesthesia via an endotracheal tube or supraglottic airway. Patients had their airway device removed in the OR or in the PACU depending on the attending anesthesiologist's preference. Upon the patient's arrival in the PACU, concentrations of exhaled sevoflurane and desflurane were measured at their breathing zone (i.e., 15 cm from the patient's mouth and nose) using a single-beam infrared spectrophotometer. Seventy patients were recruited during the five-month study period. The median [interquartile range] WAG levels in the patients' breathing zones were higher when their airway devices were removed in the PACU vs in the OR. The WAG levels for sevoflurane were 0.7 [0.4-1.1] parts per million (ppm) vs 0.5 [0.4-0.7] ppm, respectively; median difference, 0.3; 95% confidence interval (CI), 0.1 to 0.6; P = 0.04. The WAG levels for desflurane were 2.4 [1.2-3.4] ppm vs 4.1 [2.5-5.2] ppm, respectively; median difference, 1.5; 95% CI, 0.3 to 2.7; P = 0.04. After a volatile-based anesthetic, our results suggest that removal of the airway device in the PACU vs in the OR increases the amount of waste anesthetic gas in a patient's breathing zone and thus potentially in the PACU nurse's working zone.

  9. Low flow anesthesia: Efficacy and outcome of laryngeal mask airway versus pressure-optimized cuffed-endotracheal tube

    Directory of Open Access Journals (Sweden)

    El-Seify Zeinab

    2010-01-01

    Full Text Available Background: Low flow anesthesia can lead to reduction of anesthetic gas and vapor consumption. Laryngeal mask airway (LMA has proved to be an effective and safe airway device. The aim of this study is to assess the feasibility of laryngeal mask airway during controlled ventilation using low fresh gas flow (1.0 L/min as compared to endotracheal tube (ETT. Patients and Methods : Fifty nine non-smoking adult patients; ASA I or II, being scheduled for elective surgical procedures, with an expected duration of anesthesia 60 minutes or more, were randomly allocated into two groups - Group I (29 patients had been ventilated using LMA size 4 for females and 5 for males respectively; and Group II (30 patients were intubated using ETT. After 10 minutes of high fresh gas flow, the flow was reduced to 1 L/min. Patients were monitored for airway leakage, end-tidal CO 2 (ETCO 2 , inspiratory and expiratory isoflurane and nitrous oxide fraction concentrations, and postoperative airway-related complications Results : Two patients in the LMA-group developed initial airway leakage (6.9% versus no patient in ETT-group. Cough and sore throat were significantly higher in ETT patients. There were no evidences of differences between both groups regarding ETCO 2 , uptake of gases, nor difficulty in swallowing. Conclusion : The laryngeal mask airway proved to be effective and safe in establishing an airtight seal during controlled ventilation under low fresh gas flow of 1 L/min, inducing less coughing and sore throat during the immediate postoperative period than did the ETT, with continuous measurement and readjustment of the tube cuff pressure.

  10. Lung and chest wall impedances in the dog in normal range of breathing: effects of pulmonary edema.

    Science.gov (United States)

    Barnas, G M; Stamenović, D; Lutchen, K R

    1992-09-01

    We evaluated the effect of pulmonary edema on the frequency (f) and tidal volume (VT) dependences of respiratory system mechanical properties in the normal ranges of breathing. We measured resistance and elastance of the lungs (RL and EL) and chest wall of four anesthetized-paralyzed dogs during sinusoidal volume oscillations at the trachea (50-300 ml, 0.2-2 Hz), delivered at a constant mean airway pressure. Measurements were made before and after severe pulmonary edema was produced by injection of 0.06 ml/kg oleic acid into the right atrium. Chest wall properties were not changed by the injection. Before oleic acid, EL increased slightly with increasing f in each dog but was independent of VT. RL decreased slightly and was independent of VT from 0.2 to 0.4 Hz, but above 0.4 Hz it tended to increase with increasing flow, presumably due to the airway contribution. After oleic acid injection, EL and RL increased greatly. Large negative dependences of EL on VT and of RL on f were also evident, so that EL and RL after oleic acid changed two- and fivefold, respectively, within the ranges of f and VT studied. We conclude that severe pulmonary edema changes lung properties so as to make behavior VT dependent (i.e., nonlinear) and very frequency dependent in the normal range of breathing.

  11. 46 CFR 197.456 - Breathing supply hoses.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being placed...

  12. Sports-related lung injury during breath-hold diving

    Directory of Open Access Journals (Sweden)

    Tanja Mijacika

    2016-12-01

    Full Text Available The number of people practising recreational breath-hold diving is constantly growing, thereby increasing the need for knowledge of the acute and chronic effects such a sport could have on the health of participants. Breath-hold diving is potentially dangerous, mainly because of associated extreme environmental factors such as increased hydrostatic pressure, hypoxia, hypercapnia, hypothermia and strenuous exercise. In this article we focus on the effects of breath-hold diving on pulmonary function. Respiratory symptoms have been reported in almost 25% of breath-hold divers after repetitive diving sessions. Acutely, repetitive breath-hold diving may result in increased transpulmonary capillary pressure, leading to noncardiogenic oedema and/or alveolar haemorrhage. Furthermore, during a breath-hold dive, the chest and lungs are compressed by the increasing pressure of water. Rapid changes in lung air volume during descent or ascent can result in a lung injury known as pulmonary barotrauma. Factors that may influence individual susceptibility to breath-hold diving-induced lung injury range from underlying pulmonary or cardiac dysfunction to genetic predisposition. According to the available data, breath-holding does not result in chronic lung injury. However, studies of large populations of breath-hold divers are necessary to firmly exclude long-term lung damage.

  13. Fluid structure interaction simulations of the upper airway in obstructive sleep apnea patients before and after maxillomandibular advancement surgery.

    Science.gov (United States)

    Chang, Kwang K; Kim, Ki Beom; McQuilling, Mark W; Movahed, Reza

    2018-06-01

    The purpose of this study was to analyze pharyngeal airflow using both computational fluid dynamics (CFD) and fluid structure interactions (FSI) in obstructive sleep apnea patients before and after maxillomandibular advancement (MMA) surgery. The airflow characteristics before and after surgery were compared with both CFD and FSI. In addition, the presurgery and postsurgery deformations of the airway were evaluated using FSI. Digitized pharyngeal airway models of 2 obstructive sleep apnea patients were generated from cone-beam computed tomography scans before and after MMA surgery. CFD and FSI were used to evaluate the pharyngeal airflow at a maximum inspiration rate of 166 ml per second. Standard steady-state numeric formulations were used for airflow simulations. Airway volume increased, pressure drop decreased, maximum airflow velocity decreased, and airway resistance dropped for both patients after the MMA surgery. These findings occurred in both the CFD and FSI simulations. The FSI simulations showed an area of marked airway deformation in both patients before surgery, but this deformation was negligible after surgery for both patients. Both CFD and FSI simulations produced airflow results that indicated less effort was needed to breathe after MMA surgery. The FSI simulations demonstrated a substantial decrease in airway deformation after surgery. These beneficial changes positively correlated with the large improvements in polysomnography outcomes after MMA surgery. Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  14. Flexible hemispheric microarrays of highly pressure-sensitive sensors based on breath figure method.

    Science.gov (United States)

    Wang, Zhihui; Zhang, Ling; Liu, Jin; Jiang, Hao; Li, Chunzhong

    2018-05-30

    Recently, flexible pressure sensors featuring high sensitivity, broad sensing range and real-time detection have aroused great attention owing to their crucial role in the development of artificial intelligent devices and healthcare systems. Herein, highly sensitive pressure sensors based on hemisphere-microarray flexible substrates are fabricated via inversely templating honeycomb structures deriving from a facile and static breath figure process. The interlocked and subtle microstructures greatly improve the sensing characteristics and compressibility of the as-prepared pressure sensor, endowing it a sensitivity as high as 196 kPa-1 and a wide pressure sensing range (0-100 kPa), as well as other superior performance, including a lower detection limit of 0.5 Pa, fast response time (10 000 cycles). Based on the outstanding sensing performance, the potential capability of our pressure sensor in capturing physiological information and recognizing speech signals has been demonstrated, indicating promising application in wearable and intelligent electronics.

  15. Does personality play a role in continuous positive airway pressure compliance?

    Directory of Open Access Journals (Sweden)

    Emily L. Maschauer

    2017-03-01

    Continuous positive airway pressure (CPAP adherence is low among individuals with obstructive sleep apnoea. Type D personality and high scores on the depression and hypochondriasis scales on the Minnesota Multiphasic Personality Inventory (MMPI have been identified as factors contributing to non-compliance with CPAP. Further research into personality type may assist in understanding why some people adhere to CPAP, while others fail. Obstructive sleep apnoea (OSA is a condition characterised by repetitive, intermittent partial or complete collapse/obstruction of the upper airway during sleep. Continuous positive airway pressure (CPAP is highly efficacious in treating OSA but its effectiveness is limited due to suboptimal acceptance and adherence rates, with as many as 50% of OSA patients discontinuing CPAP treatment within the first year. Until recently, research has focused on examining mechanistic and demographic factors that could explain nonadherence (e.g. age, sex, race and education level with limited applicability in a prospective or clinical manner. More recent research has focused on personality factors or types of patients with OSA who comply and do not comply with CPAP adherence in an attempt to enhance the accuracy of predicting treatment compliance. Type D personality has been found to be prevalent in one third of patients with OSA. The presence of Type D personality increases noncompliance and poor treatment outcomes due to negative affectivity, social inhibition, unhealthy lifestyle, and a reluctance to consult and/or follow medical advice. Conversely, individuals who are more likely to adhere to CPAP treatment tend to have a high internal locus of control and high self-efficacy, self-refer for treatment, and have active coping skills. By assessing personality and coping skills, the clinician may gain insight into the likelihood of a patient’s adherence to treatment. If the patient displays potential risk factors for CPAP noncompliance, the

  16. Continuous positive airway pressure (CPAP).

    Science.gov (United States)

    Sahni, R; Wung, J T

    1998-01-01

    Progress in neonatal intensive care is closely linked to improvements in the management of respiratory failure in small infants. This applies to the care of the preterm infants with immature lungs, and also to treatment of the preterm or full term infants with specific diseases that are associated with respiratory failure. Respiratory distress of the newborn continues to account for significant morbidity in the intensive care unit. The spectrum of disease ranges from mild distress to severe respiratory failure requiring varying degrees of support. The current modalities of ventilatory assistance range from the more benign continuous positive airway pressure (CPAP) to conventional mechanical ventilation, and on to high frequency ventilation. It is a reasonable supposition that the type of ventilatory assistance provided to these infants should be graded according to the severity of the disease. However, the principal objective in selecting the mode of respiratory support should be to use a modality which results in minimal volo- or barotrauma to the infant. The following detailed description on CPAP explains its physiological effects, delivery system, indications for use, application, maintenance, and associated complications. The equipment described is simple to use, has a greater cost benefit, and has a more universal application, which is of help to smaller units including those in the developing parts of the world. We have also included our institutional clinical experience of CPAP usage in very low birth weight infants from the periods before and after commercial availability of surfactant in the United States.

  17. The NOFLO trial: low-flow nasal prongs therapy in weaning nasal continuous positive airway pressure in preterm infants.

    LENUS (Irish Health Repository)

    O'Donnell, Sinéad M

    2013-07-01

    To determine if low-flow nasal prongs therapy with room air, compared with no treatment, facilitates weaning from nasal continuous positive airway pressure (NCPAP) in very low birth weight (VLBW, birth weight <1500 g) infants.

  18. The analysis of volatile organic compounds in exhaled breath and biomarkers in exhaled breath condensate in children - clinical tools or scientific toys?

    Science.gov (United States)

    van Mastrigt, E; de Jongste, J C; Pijnenburg, M W

    2015-07-01

    Current monitoring strategies for respiratory diseases are mainly based on clinical features, lung function and imaging. As airway inflammation is the hallmark of many respiratory diseases in childhood, noninvasive methods to assess the presence and severity of airway inflammation might be helpful in both diagnosing and monitoring paediatric respiratory diseases. At present, the measurement of fractional exhaled nitric oxide is the only noninvasive method available to assess eosinophilic airway inflammation in clinical practice. We aimed to evaluate whether the analysis of volatile organic compounds (VOCs) in exhaled breath (EB) and biomarkers in exhaled breath condensate (EBC) is helpful in diagnosing and monitoring respiratory diseases in children. An extensive literature search was conducted in Medline, Embase and PubMed on the analysis and applications of VOCs in EB and EBC in children. We retrieved 1165 papers, of which nine contained original data on VOCs in EB and 84 on biomarkers in EBC. These were included in this review. We give an overview of the clinical applications in childhood and summarize the methodological issues. Several VOCs in EB and biomarkers in EBC have the potential to distinguish patients from healthy controls and to monitor treatment responses. Lack of standardization of collection methods and analysis techniques hampers the introduction in clinical practice. The measurement of metabolomic profiles may have important advantages over detecting single markers. There is a lack of longitudinal studies and external validation to reveal whether EB and EBC analysis have added value in the diagnostic process and follow-up of children with respiratory diseases. In conclusion, the use of VOCs in EB and biomarkers in EBC as markers of inflammatory airway diseases in children is still a research tool and not validated for clinical use. © 2014 John Wiley & Sons Ltd.

  19. [Comparison of different continuous positive airway pressure titration methods for obstructive sleep apnea hypopnea syndrome].

    Science.gov (United States)

    Li, Jingjing; Ye, Jingying; Zhang, Peng; Kang, Dan; Cao, Xin; Zhang, Yuhuan; Ding, Xiu; Zheng, Li; Li, Hongguang; Bian, Qiuli

    2014-10-01

    To explore whether there were differences between the results of automatic titration and the results of manual titration for positive airway pressure treatment in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and its influencing factors, the results might provide a theoretical basis for the rational use of two pressure titration methods. Sixty one patients with OSAHS were included in this study. All patients underwent a manual titration and an automatic titration within one week. The clinical informations, polysomnography data, and the results of both two titration of all patients were obtained for analysis. The overall apnea/hypopnea index was (63.1 ± 17.7)/h, with a range of 14.9/h to 110.4/h. The treatment pressure of manual titration was (8.4 ± 2.1) cmH(2)O, which was significantly lower than the treatment pressure of automatic titration, (11.5 ± 2.7) cmH(2)O (t = -9.797, P titration and manual titration), it was found that the pressure of automatic titration was significantly higher in patients with a ΔP > 3 cmH(2)O than in patients with a ΔP ≤ 3 cmH(2)O, which was (13.3 ± 2.3) cmH(2)O vs (10.0 ± 2.0) cmH(2)O (t = -6.159, P titration between these two groups, which was (8.6 ± 2.4) cmH(2)O vs (8.3 ± 2.0)cmH(2)O (P > 0.05). There was no significant difference in age, body mass index, neck circumference, abdomen circumference, apnea hypopnea index, and arterial oxygen saturation between these two groups. The treatment pressure of automatic titration is usually higher than that of manual titration. For patients with a high treatment pressure which is derived from automatic titration, a suggestion about manual titration could be given to decrease the potential treatment pressure of continuous positive airway pressure, which may be helpful in improving the comfortableness and the compliance of this treatment.

  20. Optimal ventilatory patterns in periodic breathing.

    Science.gov (United States)

    Ghazanshahi, S D; Khoo, M C

    1993-01-01

    The goal of this study was to determine whether periodic breathing (PB), which is highly prevalent during sleep at high altitudes, imposes physiological penalties on the respiratory system in the absence of any accompanying disease. Using a computer model of respiratory gas exchange, we compared the effects of a variety of PB patterns on the chemical and mechanical costs of breathing to those resulting from regular tidal breathing. Although PB produced considerable fluctuation in arterial blood gas tensions, for the same cycle-averaged ventilation, higher arterial oxygen saturation and lower arterial carbon dioxide levels were achieved. This result can be explained by the fact that the combination of large breaths and apnea in PB leads to a substantial reduction in dead space ventilation. At the same time, the savings in mechanical cost achieved by the respiratory muscles during apnea partially offset the increase during the breathing phase. Consequently, the "pressure cost," a criterion based on mean inspiratory pressure, was elevated only slightly, although the average work rate of breathing increased significantly. We found that, at extreme altitudes, PB patterns with clusters of 2 to 4 large breaths that alternate with apnea produce the highest arterial oxygenation levels and lowest pressure costs. The common occurrence of PB patterns with closely similar features has been reported in sleeping healthy sojourners at extreme altitudes. Taken together, these findings suggest that PB favors a reduction in the oxygen demands of the respiratory muscles and therefore may not be as detrimental as it is generally believed to be.

  1. Treatment resistant adolescent depression with upper airway resistance syndrome treated with rapid palatal expansion: a case report

    Directory of Open Access Journals (Sweden)

    Miller Paul

    2012-12-01

    Full Text Available Abstract Introduction To the best of our knowledge, this is the first report of a case of treatment-resistant depression in which the patient was evaluated for sleep disordered breathing as the cause and in which rapid palatal expansion to permanently treat the sleep disordered breathing produced a prolonged symptom-free period off medication. Case presentation An 18-year-old Caucasian man presented to our sleep disorders center with chronic severe depression that was no longer responsive to medication but that had recently responded to electroconvulsive therapy. Ancillary, persistent symptoms included mild insomnia, moderate to severe fatigue, mild sleepiness and severe anxiety treated with medication. Our patient had no history of snoring or witnessed apnea, but polysomnography was consistent with upper airway resistance syndrome. Although our patient did not have an orthodontic indication for rapid palatal expansion, rapid palatal expansion was performed as a treatment of his upper airway resistance syndrome. Following rapid palatal expansion, our patient experienced a marked improvement of his sleep quality, anxiety, fatigue and sleepiness. His improvement has been maintained off all psychotropic medication and his depression has remained in remission for approximately two years following his electroconvulsive therapy. Conclusions This case report introduces the possibility that unrecognized sleep disordered breathing may play a role in adolescent treatment-resistant depression. The symptoms of upper airway resistance syndrome are non-specific enough that every adolescent with depression, even those responding to medication, may have underlying sleep disordered breathing. In such patients, rapid palatal expansion, by widening the upper airway and improving airflow during sleep, may produce a prolonged improvement of symptoms and a tapering of medication. Psychiatrists treating adolescents may benefit from having another treatment option for

  2. Randomized crossover comparison of the laryngeal mask airway classic with i-gel laryngeal mask airway in the management of difficult airway in post burn neck contracture patients

    Directory of Open Access Journals (Sweden)

    Jeevan Singh

    2012-01-01

    Full Text Available Purpose: The objective of the study was to compare the performance of i-gel supraglottic airway with cLMA in difficult airway management in post burn neck contracture patients and assess the feasibility of i-gel use for emergency airway management in difficult airway situation with reduced neck movement and limited mouth opening. Methods: Prospective, crossover, randomized controlled trial was performed amongst forty eight post burn neck contracture patients with limited mouth opening and neck movement. i-gel and cLMA were placed in random order in each patient. Primary outcome was overall success rate. Other measurements were time to successful ventilation, airway leak pressure, fiberoptic glottic view, visualization of square wave pattern. Results: Success rate for the i-gel was 91.7% versus 79.2% for the cLMA. i-gel required shorter insertion time (19.3 seconds vs. 23.5 seconds, P=0.000. Airway leak pressure difference was statistically significant (i-gel 21.2 cm H20; cLMA 16.9 cm H 2 0; P=0.00. Fiberoptic view through the i-gel showed there were less epiglottic downfolding and better fiberoptic view of the glottis than cLMA. Overall agreement in insertion outcome for i-gel was 22/24 (91.7% successes and 2/24(8.3% failure and for cLMA, 19/24 (79.16% successes and 5/24 (16.7% failure in the first attempt. Conclusion: The i-gel is cheap, effective airway device which is easier to insert and has better clinical performance in the difficult airway management of the airway in the post burn contracture of the neck. Our study shows that i-gel is feasible for emergency airway management in difficult airway situation with reduced neck movement and limited mouth opening in post burn neck.

  3. Importance of Functional Airway Surgery in Orthognathic Surgery Performed Patients

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    Erkan Yüce

    2017-06-01

    Full Text Available Le Fort I osteotomy is usually combined with mandibular ramus procedures (sagittal split in order to correct dentofacial deformities that cause malocclusion. Patients who have dentofacial anomalies involving the maxilla carry a higher risk of difficulty in breathing due to septal deviation and inferior turbinate hypertrophy. If these conditions are ignored preoperatively, severe airway problems may come up after orthognathic surgery. A detailed examination regarding nasal airway should be conducted in such patients, and they should be informed about their condition which may require an additional intervention during or after their main surgery.

  4. Efficacy of daytime continuous positive airway pressure titration in severe obstructive sleep apnoea.

    Science.gov (United States)

    Rudkowski, J C; Verschelden, P; Kimoff, R J

    2001-09-01

    The aim of this study was to evaluate manual nasal continuous positive airway pressure (nCPAP) titration during daytime polysomnography compared with conventional overnight titration for patients with severe obstructive sleep apnoea. Thirty-two patients who underwent daytime titration were retrospectively matched (for age, sex, body mass index and apnoea/hypopnoea index (AHI)) to a group titrated overnight during the same period. Successful titration was defined as the identification of the nCPAP level (effective nCPAP (Peff)) required to eliminate respiratory events during all sleep stages. After 3 months of therapy on nCPAP at Peff, nCPAP utilization history was obtained and a group of patients underwent a repeat polysomnogram (PSG) and completed a follow-up Epworth Sleepiness Scale (ESS) score. Initial titration was successful in 91% of daytime patients and 91% of overnight patients. The success of daytime titration was not related to diagnostic AHI or ESS score. Subjective nCPAP utilization was statistically similar in both groups. On the follow-up PSG, there were no significant differences between daytime (n=11) and overnight (n=11) patients in measures of sleep quality or respiratory disturbance. Both groups demonstrated similar and significant improvements in ESS score. These findings suggest that the effective nasal continuous positive airway pressure can be accurately established during daytime titration in a substantial proportion of severe, symptomatic obstructive sleep apnoea patients.

  5. A new device for administration of continuous positive airway pressure in preterm infants: comparison with a standard nasal CPAP continuous positive airway pressure system.

    Science.gov (United States)

    Trevisanuto, Daniele; Grazzina, Nicoletta; Doglioni, Nicoletta; Ferrarese, Paola; Marzari, Francesco; Zanardo, Vincenzo

    2005-06-01

    We compared the effectiveness of a new continuous positive airway pressure (CPAP) device (neonatal helmet CPAP) with a conventional nasal CPAP system in preterm neonates needing continuous distending pressure. Randomized, physiological, cross-over study in a tertiary referral, neonatal intensive care unit in a university teaching hospital. Twenty very low birth weight infants with a postnatal age greater than 24 h who were receiving nasal CPAP for apnea and/or mild respiratory distress were enrolled. CPAP delivered by neonatal helmet CPAP and nasal CPAP in random order for two subsequent 90-min periods. Were continuously measured the Neonatal Infant Pain Scale (NIPS) score, oxygen requirements, respiratory rate, heart rate, oxygen saturation, transcutaneous PO(2) (tcPO(2)) and PCO(2) (tcPCO(2)), blood pressure, and desaturations. NIPS scores were significantly lower when the infants were on the neonatal helmet CPAP than when they were on nasal CPAP (0.26+/-0.07 vs. 0.63+/-0.12). The other studied parameters did not differ between the two CPAP modes. The number of desaturations was reduced during the neonatal helmet CPAP treatment (18 vs. 32), although this difference was not significant. In this short-term physiological study the neonatal helmet CPAP appears to be as good as the golden standard for managing preterm infants needing continuous distending pressure, with enhanced tolerability. Further evaluation in a randomized clinical trial is needed to confirm these findings.

  6. Nasal highflow improves ventilation in patients with COPD

    Directory of Open Access Journals (Sweden)

    Bräunlich J

    2016-05-01

    Full Text Available Jens Bräunlich,* Marcus Köhler,* Hubert WirtzDepartment of Respiratory Medicine, University of Leipzig, Leipzig, Germany *These authors contributed equally to this workBackground: Nasal highflow (NHF provides a warmed and humidified air stream up to 60 L/min. Recent data demonstrated a positive effect in patients with acute hypoxemic respiratory failure, especially when caused by pneumonia. Preliminary data show a decrease in hypercapnia in patients with COPD. Therefore, NHF should be evaluated as a new ventilatory support device. This study was conducted to assess the impact of different flow rates on ventilatory parameters in patients with COPD.Materials and methods: This interventional clinical study was performed with patients suffering from severe COPD. The aim was to characterize flow-dependent changes in mean airway pressure, breathing volumes, breathing frequency, and decrease in partial pressure of CO2 (pCO2. Mean airway pressure was measured in the nasopharyngeal space (19 patients. To evaluate breathing volumes, we used a polysomnographic device (18 patients. All patients received 20 L/min, 30 L/min, 40 L/min, and 50 L/min and – to illustrate the effects – nasal continuous positive airway pressure and nasal bilevel positive airway pressure. Capillary blood gas analyses were performed in 54 patients with hypercapnic COPD before and two hours after the use of NHF. We compared the extent of decrease in pCO2 when using 20 L/min and 30 L/min. Additionally, comfort and dyspnea during the use of NHF were surveyed.Results: NHF resulted in a minor flow dependent increase in mean airway pressure. Tidal volume increased, and breathing rate decreased. The calculated minute volume decreased under NHF breathing. In spite of this fact, hypercapnia decreased with increasing flow (20 L/min vs 30 L/min. Additionally, an improvement in dyspnea was observed. The rapid shallow breathing index shows a decrease when using NHF.Conclusion: NHF

  7. The effect of continuous positive airway pressure on blood pressure in patients with obstructive sleep apnea syndrome

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    Giorgiana Dediu

    2017-12-01

    Full Text Available Introduction. Obstructive sleep apnea syndrome (OSAS is a disease with increasing prevalence nowadays, being associated with multiple cardiovascular diseases, such as arterial hypertension. The objective of the study was to evaluate the effect of continuous positive airway pressure (CPAP on blood pressure values. Materials and methods. We performed a prospective interventional study on 52 patients with obstructive sleep apnea syndrome. The patients were divided into 2 groups: Group A (who received both pharmacological and CPAP treatment and Group B (who received only pharmacological treatment, and were followed up at 3 and 6 months. The statistical analysis was made with SPSS and Microsoft Excel. At the same time, using the surrogate marker –RDW, we tried to evaluate the persistence of systemic inflammation, knowing that OSAS is associated with inflammation. Results. The systolic blood pressure values decreased at 6 months in all OSAS patients who have used CPAP, including patients with normal values of blood pressure. At the same time, the lack of OSAS treatment led to increased values of blood pressure by approximately 10 mmHg. We noticed a link between RDW, age and blood pressure values, respectively the increase of RDW and age may result in an increase in blood pressure. Conclusions. The OSAS treatment can decrease the blood pressure values. A higher RDW may be considered a negative prognostic factor for these patients, reflecting the role of systemic inflammation in the appearance of cardiovascular disorders.

  8. Mechanisms of mechanical strain memory in airway smooth muscle.

    Science.gov (United States)

    Kim, Hak Rim; Hai, Chi-Ming

    2005-10-01

    We evaluated the hypothesis that mechanical deformation of airway smooth muscle induces structural remodeling of airway smooth muscle cells, thereby modulating mechanical performance in subsequent contractions. This hypothesis implied that past experience of mechanical deformation was retained (or "memorized") as structural changes in airway smooth muscle cells, which modulated the cell's subsequent contractile responses. We termed this phenomenon mechanical strain memory. Preshortening has been found to induce attenuation of both force and isotonic shortening velocity in cholinergic receptor-activated airway smooth muscle. Rapid stretching of cholinergic receptor-activated airway smooth muscle from an initial length to a final length resulted in post-stretch force and myosin light chain phosphorylation that correlated significantly with initial length. Thus post-stretch muscle strips appeared to retain memory of the initial length prior to rapid stretch (mechanical strain memory). Cytoskeletal recruitment of actin- and integrin-binding proteins and Erk 1/2 MAPK appeared to be important mechanisms of mechanical strain memory. Sinusoidal length oscillation led to force attenuation during oscillation and in subsequent contractions in intact airway smooth muscle, and p38 MAPK appeared to be an important mechanism. In contrast, application of local mechanical strain to cultured airway smooth muscle cells induced local actin polymerization and cytoskeletal stiffening. It is conceivable that deep inspiration-induced bronchoprotection may be a manifestation of mechanical strain memory such that mechanical deformation from past breathing cycles modulated the mechanical performance of airway smooth muscle in subsequent cycles in a continuous and dynamic manner.

  9. A clinical comparison of disposable airway devices | Strydom ...

    African Journals Online (AJOL)

    Cuff pressures were significantly higher in the Ambu™ and LMA Unique™ (p = 0.001). Maximum airway pressure attainable after 5 minutes was significantly higher in the Ambu™ (p = 0.036). Airway trauma as graded by visible blood on the device was low, and similar between groups (p = 0.237). Secretions were negligible ...

  10. Sleep-Disordered Breathing in Heart Failure - A Therapeutic Dilemma.

    Science.gov (United States)

    Haruki, Nobuhiko; Floras, John S

    2017-06-23

    Sleep-disordered breathing (SDB) occurs in approximately 50% of patients with reduced left ventricular ejection fraction receiving contemporary heart failure (HF) therapies. Obstructive (OSA) and central sleep apneas (CSA) interrupt breathing by different mechanisms but impose qualitatively similar autonomic, chemical, mechanical, and inflammatory burdens on the heart and circulation. Because contemporary evidence-based drug and device HF therapies have little or no mitigating effect on the acute or long-term consequences of such stimuli, there is a sound mechanistic rationale for targeting SDB to reduce cardiovascular event rates and prolong life. However, the promise of observational studies and randomized trials of small size and duration describing a beneficial effect of treating SDB in HF via positive airway pressure was not realized in 2 recent randomized outcome-driven trials: SAVE, which evaluated the cardiovascular effect of treating OSA in a cohort without HF, and SERVE-HF, which reported the results of a strategy of random allocation of minute-ventilation-triggered adaptive servo-ventilation (ASV) for HF patients with CSA. Whether effective treatment of either OSA or CSA improves the HF trajectory by reducing cardiovascular morbidity or mortality has yet to be definitively established. ADVENT-HF, designed to determine the effect of treating both CSA and non-sleepy OSA HF patients with a peak-airflow triggered ASV algorithm, could resolve this present clinical equipoise concerning the treatment of SDB.

  11. The lung cancer breath signature: a comparative analysis of exhaled breath and air sampled from inside the lungs

    Science.gov (United States)

    Capuano, Rosamaria; Santonico, Marco; Pennazza, Giorgio; Ghezzi, Silvia; Martinelli, Eugenio; Roscioni, Claudio; Lucantoni, Gabriele; Galluccio, Giovanni; Paolesse, Roberto; di Natale, Corrado; D'Amico, Arnaldo

    2015-11-01

    Results collected in more than 20 years of studies suggest a relationship between the volatile organic compounds exhaled in breath and lung cancer. However, the origin of these compounds is still not completely elucidated. In spite of the simplistic vision that cancerous tissues in lungs directly emit the volatile metabolites into the airways, some papers point out that metabolites are collected by the blood and then exchanged at the air-blood interface in the lung. To shed light on this subject we performed an experiment collecting both the breath and the air inside both the lungs with a modified bronchoscopic probe. The samples were measured with a gas chromatography-mass spectrometer (GC-MS) and an electronic nose. We found that the diagnostic capability of the electronic nose does not depend on the presence of cancer in the sampled lung, reaching in both cases an above 90% correct classification rate between cancer and non-cancer samples. On the other hand, multivariate analysis of GC-MS achieved a correct classification rate between the two lungs of only 76%. GC-MS analysis of breath and air sampled from the lungs demonstrates a substantial preservation of the VOCs pattern from inside the lung to the exhaled breath.

  12. 46 CFR 197.312 - Breathing supply hoses.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The maximum...

  13. Effect of inspiration on airway dimensions measured in maximal inspiration CT images of subjects without airflow limitation

    DEFF Research Database (Denmark)

    Petersen, Jens; Wille, Mathilde M.W.; Raket, Lars Lau

    2014-01-01

    . Automated software was utilized to segment lungs and airways, identify segmental bronchi, and match airway branches in all images of the same subject. Inspiration level was defined as segmented total lung volume (TLV) divided by predicted total lung capacity (pTLC). Mixed-effects models were used to predict......OBJECTIVES: To study the effect of inspiration on airway dimensions measured in voluntary inspiration breath-hold examinations. METHODS: 961 subjects with normal spirometry were selected from the Danish Lung Cancer Screening Trial. Subjects were examined annually for five years with low-dose CT...... • The effect of inspiration is greater in higher-generation (more peripheral) airwaysAirways of generation 5 and beyond are as distensible as lung parenchyma • Airway dimensions measured from CT should be adjusted for inspiration level....

  14. Mucociliary clearance, airway inflammation and nasal symptoms in urban motorcyclists

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    Tereza C.S. Brant

    2014-01-01

    Full Text Available OBJECTIVES: There is evidence that outdoor workers exposed to high levels of air pollution exhibit airway inflammation and increased airway symptoms. We hypothesized that these workers would experience increased airway symptoms and decreased nasal mucociliary clearance associated with their exposure to air pollution. METHODS: In total, 25 non-smoking commercial motorcyclists, aged 18-44 years, were included in this study. These drivers work 8-12 hours per day, 5 days per week, driving on urban streets. Nasal mucociliary clearance was measured by the saccharine transit test; airway acidification was measured by assessing the pH of exhaled breath condensate; and airway symptoms were measured by the Sino-nasal Outcome Test-20 questionnaire. To assess personal air pollution exposure, the subjects used a passive-diffusion nitrogen dioxide (NO2 concentration-monitoring system during the 14 days before each assessment. The associations between NO2 and the airway outcomes were analyzed using the Mann-Whitney test and the Chi-Square test. Clinicaltrials.gov: NCT01976039. RESULTS: Compared with clearance in healthy adult males, mucociliary clearance was decreased in 32% of the motorcyclists. Additionally, 64% of the motorcyclists had airway acidification and 92% experienced airway symptoms. The median personal NO2 exposure level was 75 mg/m3 for these subjects and a significant association was observed between NO2 and impaired mucociliary clearance (p = 0.036. CONCLUSION: Non-smoking commercial motorcyclists exhibit increased airway symptoms and airway acidification as well as decreased nasal mucociliary clearance, all of which are significantly associated with the amount of exposure to air pollution.

  15. Airway inflammation in chronic obstructive pulmonary disease (COPD): a true paradox.

    Science.gov (United States)

    Eapen, Mathew Suji; Myers, Stephen; Walters, Eugene Haydn; Sohal, Sukhwinder Singh

    2017-10-01

    Chronic obstructive pulmonary disease (COPD) is primarily an airway condition, which mainly affects cigarette smokers and presents with shortness of breath that is progressive and poorly reversible. In COPD research, there has been a long held belief that airway disease progression is due to inflammation. Although this may be true in the airway lumen with innate immunity activated by the effect of smoke or secondary to infection, the accurate picture of inflammatory cells in the airway wall, where the pathophysiological COPD remodeling occurs, is uncertain and debatable. Areas covered: The current review provides a comprehensive literature survey of the changes in the main inflammatory cells in human COPD patients and focuses on contrarian views that affect the prevailing dogma on inflammation. The review also delves into the role of oxidative stress and inflammasomes in modulating the immune response in COPD. Further, the effects of inflammation in affecting the epithelium, fibroblasts, and airway remodeling are discussed. Expert commentary: Inflammation as a driving force for airway wall damage and remodelling in early COPD is at the very least 'oversimplified' and is likely to be misleading. This has serious implications for rational thinking about the illness, including pathogenesis and designing therapy.

  16. A comprehensive scoring system in correlation with perioperative airway management for neonatal Pierre Robin Sequence.

    Directory of Open Access Journals (Sweden)

    Ning Yin

    Full Text Available To evaluate a comprehensive scoring system which combines clinical manifestations of Pierre Robin Sequence (PRS including severity of breathing difficulties, body weight and preoperative Cormack-Lehane grade, for its correlation with perioperative PRS airway management decision.Forty PRS children were retrospectively recruited after surgery. Specialists examined all subjects and scored for clinical manifestations (1´ - 4´, weight gain (1´- 4´, dyspnea scores (1´- 4´, and Cormack-Lehane grade (1´- 4´. The correlation of the integrated scores and the necessity of endotracheal intubation or laryngeal mask application were analyzed. In addition, the score correlation with postoperative dyspnea and/or low pulse oxygen saturation (SPO2 levels after extubation was determined.In our study every individual patient had a score from 0´ to 16´, while the higher in the numbers represented higher risk of breathing difficulty. All patients with comprehensive scores 13 points required a laryngeal mask assisted airway management and were considered to have difficult airways. Dyspnea after extubation and postoperative low SPO2 occurred among patients who scored over 10 points.In PRS patients, preoperative weight gaining status and severity of dyspnea in combination with Cormack-Lehane classification provide a scoring system that could help to optimize airway management decisions such as endotracheal intubation or laryngeal mask airway placement and has the potential to predict postoperative dyspnea or low SPO2 levels.

  17. The effect of CO2 on ventilation and breath-holding during exercise and while breathing through an added resistance.

    Science.gov (United States)

    Clark, T J; Godfrey, S

    1969-05-01

    1. Ventilation was measured while subjects were made to rebreathe from a bag containing CO(2) and O(2) in order to expose them to a steadily rising CO(2) tension (P(CO2)). The object of the experiments was to determine the effect of a variety of stimuli upon the increase in ventilation and fall in breath-holding time which occurs in response to the rising P(CO2).2. Steady-state exercise at 200 kg.m/min resulted in a small fall in the slope of the ventilation-CO(2) response curve (S(V)) and a small, though not statistically significant, fall in the P(CO2) at which ventilation would be zero by extrapolation (B(V)). There was a marked fall in the slope of the breath-holding-CO(2) response curve (S(BH)) and an increase in the P(CO2) at which breath-holding time became zero by extrapolation (B(BH)).3. These results have been interpreted with the aid of a model of the control of breath-holding and it is suggested that there is no change in CO(2) sensitivity on exercise, either during rebreathing or breath-holding.4. An increase in the resistance to breathing caused a marked reduction in S(V) and B(V), but no change in the breath-holding-CO(2) response curve. These findings suggest that the flattening of the ventilation-CO(2) response curve is mechanical in origin and acute airway obstruction produces no change in CO(2) sensitivity.5. On the basis of these results, we suggest that more information about CO(2) sensitivity can be obtained by a combination of ventilation and breath-holding-CO(2) response curves.

  18. Comparison of Laryngeal Mask Airway Supreme and Laryngeal Mask Airway Proseal with respect to oropharyngeal leak pressure during laparoscopic cholecystectomy: a randomised controlled trial.

    Science.gov (United States)

    Beleña, José M; Núñez, Mónica; Anta, Diego; Carnero, Maria; Gracia, José L; Ayala, José L; Alvarez, Raquel; Yuste, Javier

    2013-03-01

    A comparison of the efficacy and safety of the Laryngeal Mask Airway (LMA) Supreme (LMAS) versus the LMA Proseal (LMAP) in elective laparoscopic cholecystectomy. To compare the LMAS with LMAP in terms of ventilatory efficacy, airway leak pressure (airway protection), ease-of-use and complications. Prospective, single-blind, randomised, controlled study. The Hospital del Sureste and Hospital Ramon y Cajal, Madrid, between May 2009 and March 2011. The Hospital del Sureste is a secondary hospital and Hospital Ramon y Cajal is a tertiary hospital. Patients undergoing elective laparoscopic cholecystectomy were studied following informed consent. Inclusion criteria were American Society of Anesthesiologists physical status I to III and age 18 or more. Exclusion criteria were BMI more than 40 kg m, symptomatic hiatus hernia or severe gastro-oesophageal reflux. Anaesthesiologists experienced in the use of LMAP and LMAS participated in the trial. One hundred twenty-two patients were randomly allocated to LMAS or LMAP. Our primary outcome measure was the oropharyngeal leak pressure (OLP). Secondary outcomes were the time and number of attempts for insertion, ease of insertion of the drain tube, adequacy of ventilation and the incidence of complication. Patients were interviewed postoperatively to evaluate the presence of sore throat, dysphagia or dysphonia. Two patients were excluded when surgery changed from laparoscopic to open. A total of 120 patients were finally included in the analysis. The mean OLP in the LMAP group was significantly higher than that in the LMAS group (30.7 ± 6.2 versus 26.8 ± 4.1 cmH2O;P drain tube, complications and postoperative pharyngolaryngeal adverse events were similar in both groups. The LMAP has a higher OLP and achieves a higher maximum tidal volume compared to the LMAS, in patients undergoing elective laparoscopic cholecystectomy. The success of the first attempt insertion was higher for the LMAS.

  19. Liquid breathing - Prevention of pulmonary arterial-venous shunting during acceleration.

    Science.gov (United States)

    Sass, D. J.; Ritman, E. L.; Caskey, P. E.; Banchero, N.; Wood, E. H.

    1972-01-01

    Dependent pulmonary atelectasis, arterial-venous shunting, and downward displacement of the heart caused by the gravitational-inertial force environment were prevented in dogs breathing oxygenated liquid fluorocarbon in a whole-body water-immersion respirator. Partial closure of the major airways during part of the expiratory phase of liquid respiration was a significant problem initially but was minimized in subsequent studies.

  20. Symptoms of insomnia among patients with obstructive sleep apnea before and after two years of positive airway pressure treatment.

    Science.gov (United States)

    Björnsdóttir, Erla; Janson, Christer; Sigurdsson, Jón F; Gehrman, Philip; Perlis, Michael; Juliusson, Sigurdur; Arnardottir, Erna S; Kuna, Samuel T; Pack, Allan I; Gislason, Thorarinn; Benediktsdóttir, Bryndis

    2013-12-01

    To assess the changes of insomnia symptoms among patients with obstructive sleep apnea (OSA) from starting treatment with positive airway pressure (PAP) to a 2-y follow-up. Longitudinal cohort study. Landspitali--The National University Hospital of Iceland. There were 705 adults with OSA who were assessed prior to and 2 y after starting PAP treatment. PAP treatment for OSA. All patients underwent a medical examination along with a type 3 sleep study and answered questionnaires on health and sleep before and 2 y after starting PAP treatment. The change in prevalence of insomnia symptoms by subtype was assessed by questionnaire and compared between individuals who were using or not using PAP at follow-up. Symptoms of middle insomnia were most common at baseline and improved significantly among patients using PAP (from 59.4% to 30.7%, P insomnia tended to persist regardless of PAP treatment, and symptoms of late insomnia were more likely to improve among patients not using PAP. Patients with symptoms of initial and late insomnia at baseline were less likely to adhere to PAP (odds ratio [OR] 0.56, P = 0.007, and OR 0.53, P insomnia. Symptoms of initial and late insomnia, however, tended to persist regardless of positive airway pressure treatment and had a negative effect on adherence. Targeted treatment for insomnia may be beneficial for patients with obstructive sleep apnea comorbid with insomnia and has the potential to positively affect adherence to positive airway pressure.

  1. Evaluation of Pressure Generated by Resistors From Different Positive Expiratory Pressure Devices.

    Science.gov (United States)

    Fagevik Olsén, Monika; Carlsson, Maria; Olsén, Erik; Westerdahl, Elisabeth

    2015-10-01

    Breathing exercises with positive expiratory pressure (PEP) are used to improve pulmonary function and airway clearance. Different PEP devices are available, but there have been no studies that describe the pressure generated by different resistors. The purpose of this study was to compare pressures generated from the proprietary resistor components of 4 commercial flow-dependent PEP valves with all other parameters kept constant. Resistors from 4 flow-regulated PEP devices (Pep/Rmt system, Wellspect HealthCare; Pipe P breathing exerciser, Koo Medical Equipment; Mini-PEP, Philips Respironics [including resistors by Rüsch]; and 15-mm endo-adapter, VBM Medizintechnik) were tested randomly by a blinded tester at constant flows of 10 and 18 L/min from an external gas system. All resistors were tested 3 times. Resistors with a similar diameter produced statistically significant different pressures at the same flow. The differences were smaller when the flow was 10 L/min compared with 18 L/min. The differences were also smaller when the diameter of the resistor was increased. The pressures produced by the 4 resistors of the same size were all significantly different when measuring 1.5- and 2.0-mm resistors at a flow of 10 L/min and 2.0-mm resistors at a flow of 18 L/min (P < .001). There were no significant differences between any of the resistors when testing sizes of 4.5 and 5.0 mm at either flow. The Mini-PEP and adapter resistors gave the highest pressures. Pressures generated by the different proprietary resistor components of 4 commercial PEP devices were not comparable, even though the diameter of the resistors is reported to be the same. The pressures generated were significantly different, particularly when using small-diameter resistors at a high flow. Therefore, the resistors may not be interchangeable. This is important information for clinicians, particularly when considering PEP for patients who do not tolerate higher pressures. Copyright © 2015 by

  2. Details of regional particle deposition and airflow structures in a realistic model of human tracheobronchial airways: two-phase flow simulation.

    Science.gov (United States)

    Rahimi-Gorji, Mohammad; Gorji, Tahereh B; Gorji-Bandpy, Mofid

    2016-07-01

    In the present investigation, detailed two-phase flow modeling of airflow, transport and deposition of micro-particles (1-10µm) in a realistic tracheobronchial airway geometry based on CT scan images under various breathing conditions (i.e. 10-60l/min) was considered. Lagrangian particle tracking has been used to investigate the particle deposition patterns in a model comprising mouth up to generation G6 of tracheobronchial airways. The results demonstrated that during all breathing patterns, the maximum velocity change occurred in the narrow throat region (Larynx). Due to implementing a realistic geometry for simulations, many irregularities and bending deflections exist in the airways model. Thereby, at higher inhalation rates, these areas are prone to vortical effects which tend to entrap the inhaled particles. According to the results, deposition fraction has a direct relationship with particle aerodynamic diameter (for dp=1-10µm). Enhancing inhalation flow rate and particle size will largely increase the inertial force and consequently, more particle deposition is evident suggesting that inertial impaction is the dominant deposition mechanism in tracheobronchial airways. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Hyperinflation and intrinsic positive end-expiratory pressure: less room to breathe.

    Science.gov (United States)

    Krieger, Bruce P

    2009-01-01

    Clinically, the symptoms and limited exercise capabilities of patients with chronic obstructive pulmonary disease (COPD) correlate better with changes in lung volumes than with airflow measurements. The realization of the clinical importance of hyperinflation has been overshadowed for decades by the use of forced expiratory volume during 1 s (FEV(1)) and the ratio of the FEV(1) to the forced expiratory vital capacity (FEV(1)/FVC) to categorize the severity and progression of COPD. Hyperinflation is defined as an elevation in the end-expiratory lung volume or functional residual capacity. When severe hyperinflation encroaches upon inspiratory capacity and limits vital capacity, it results in elevated intrinsic positive end-expiratory pressure (PEEPi) that places the diaphragm at a mechanical disadvantage and increases the work of breathing. Severe hyperinflation is the major physiologic cause of the resulting hypercarbic respiratory failure and patients' inability to transition (i.e. wean) from mechanical ventilatory support to spontaneous breathing. This paper reviews the basic physiologic principles of hyperinflation and its clinical manifestations as demonstrated by PEEPi. Also reviewed are the adverse effects of hyperinflation and PEEPi in critically ill patients with COPD, and methods for minimizing or counterbalancing these effects. Copyright 2009 S. Karger AG, Basel.

  4. Effects of short-term pressure-controlled ventilation on gas exchange, airway pressures, and gas distribution in patients with acute lung injury/ARDS: comparison with volume-controlled ventilation.

    Science.gov (United States)

    Prella, Maura; Feihl, François; Domenighetti, Guido

    2002-10-01

    The potential clinical benefits of pressure-controlled ventilation (PCV) over volume-controlled ventilation (VCV) in patients with acute lung injury (ALI) or ARDS still remain debated. We compared PCV with VCV in patients with ALI/ARDS with respect to the following physiologic end points: (1) gas exchange and airway pressures, and (2) CT scan intrapulmonary gas distribution at end-expiration. Prospective, observational study. A multidisciplinary ICU in a nonuniversity, acute-care hospital. Ten patients with ALI or ARDS (9 men and 1 woman; age range, 17 to 80 years). Sequential ventilation in PCV and VCV with a constant inspiratory/expiratory ratio, tidal volume, respiratory rate, and total positive end-expiratory pressure; measurement of gas exchange and airway pressures; and achievement of CT sections at lung base, hilum, and apex for the quantitative analysis of lung densities and of aerated vs nonaerated zones. PaO(2), PaCO(2), and PaO(2)/fraction of inspired oxygen ratio levels did not differ between PCV and VCV. Peak airway pressure (Ppeak) was significantly lower in PCV compared with VCV (26 +/- 2 cm H(2)O vs 31 +/- 2 cm H(2)O; p mean +/- SEM). The surface areas of the nonaerated zones as well as the total areas at each section level were unchanged in PCV compared with VCV, except at the apex level, where there was a significantly greater nonaerated area in VCV (11 +/- 2 cm(2) vs 9 +/- 2 cm(2); p mean CT number of each lung (20 lungs from 10 patients) was similar in the two modes, as were the density values at the basal and apical levels; the hilum mean CT number was - 442 +/- 28 Hounsfield units (HU) in VCV and - 430 +/- 26 HU in PCV (p lower Ppeaks through the precise titration of the lung distending pressure, and might be applied to avoid regional overdistension by means of a more homogeneous gas distribution.

  5. Breathing and Singing: Objective Characterization of Breathing Patterns in Classical Singers.

    Science.gov (United States)

    Salomoni, Sauro; van den Hoorn, Wolbert; Hodges, Paul

    2016-01-01

    Singing involves distinct respiratory kinematics (i.e. movements of rib cage and abdomen) to quiet breathing because of different demands on the respiratory system. Professional classical singers often advocate for the advantages of an active control of the abdomen on singing performance. This is presumed to prevent shortening of the diaphragm, elevate the rib cage, and thus promote efficient generation of subglottal pressure during phonation. However, few studies have investigated these patterns quantitatively and inter-subject variability has hindered the identification of stereotypical patterns of respiratory kinematics. Here, seven professional classical singers and four untrained individuals were assessed during quiet breathing, and when singing both a standard song and a piece of choice. Several parameters were extracted from respiratory kinematics and airflow, and principal component analysis was used to identify typical patterns of respiratory kinematics. No group differences were observed during quiet breathing. During singing, both groups adapted to rhythmical constraints with decreased time of inspiration and increased peak airflow. In contrast to untrained individuals, classical singers used greater percentage of abdominal contribution to lung volume during singing and greater asynchrony between movements of rib cage and abdomen. Classical singers substantially altered the coordination of rib cage and abdomen during singing from that used for quiet breathing. Despite variations between participants, principal component analysis revealed consistent pre-phonatory inward movements of the abdominal wall during singing. This contrasted with untrained individuals, who demonstrated synchronous respiratory movements during all tasks. The inward abdominal movements observed in classical singers elevates intra-abdominal pressure and may increase the length and the pressure-generating capacity of rib cage expiratory muscles for potential improvements in voice

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

    Directory of Open Access Journals (Sweden)

    N.G. Koulouris

    2011-09-01

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

  7. An Acute Bout of a Controlled Breathing Frequency Lowers Sympathetic Neural Outflow but not Blood Pressure in Healthy Normotensive Subjects

    Science.gov (United States)

    MCCLAIN, SHANNON L.; BROOKS, ALEXA M.; JARVIS, SARA S.

    2017-01-01

    Controlled or paced breathing is often used as a stress reduction technique but the impact on blood pressure (BP) and sympathetic outflow have not been consistently reported. The purpose of this study was to determine whether a controlled breathing (12 breaths/min, CB) rate would be similar to an individual’s spontaneous breathing (SB) rate. Secondly, would a CB rate of 12 breaths/min alter heart rate (HR), BP, and indices of muscle sympathetic nerve activity (MSNA). Twenty-one subjects (10 women, 11 men) performed two trials: SB, where the subject chose a comfortable breathing rate; and CB, where the subject breathed at a pace of 12 breaths/min. Each trial was 6 min during which respiratory waveforms, HR, BP (systolic, SBP; diastolic, DBP), and MSNA were recorded. During CB, the 6 min average breathing frequency (14±4 vs 12±1 breaths/min, P<0.05 for SB and CB, respectively), MSNA burst frequency (18±12 vs 14±10 bursts/min, P<0.01) and MSNA burst incidence (28±19 vs 21± 6 bursts/100 heart beats, P<0.01) were significantly lower than during SB. HR (66±9 vs 67±9 beats/min, P<0.05) was higher during CB. SBP (120±13 vs 121±15 mmHg, P=0.741), DBP (56±8 vs 57±9 mmHg, P=0.768), and MSNA total activity (166±94 vs 145±102 a.u./min, P=0.145) were not different between the breathing conditions. In conclusion, an acute reduction in breathing frequency such as that observed during CB elicited a decrease in indices of MSNA (burst frequency and incidence) with no change in BP. PMID:28344733

  8. Retrospective, nonrandomized controlled study on autoadjusting, dual-pressure positive airway pressure therapy for a consecutive series of complex insomnia disorder patients

    Directory of Open Access Journals (Sweden)

    Krakow B

    2017-03-01

    Full Text Available Barry Krakow,1–3 Natalia D McIver,1,2 Victor A Ulibarri,1,2 Michael R Nadorff4,5 1Sleep & Human Health Institute, 2Maimonides Sleep Arts & Sciences, Ltd, Albuquerque, 3Los Alamos Medical Center, Los Alamos, NM, 4Department of Psychology, Mississippi State University, Mississippi, MS, 5Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX, USA Purpose: Emerging evidence shows that positive airway pressure (PAP treatment of obstructive sleep apnea (OSA and upper airway resistance syndrome (UARS in chronic insomnia patients (proposed “complex insomnia” disorder leads to substantial decreases in insomnia severity. Although continuous PAP (CPAP is the pressure mode most widely researched, intolerance to fixed pressurized air is rarely investigated or described in comorbidity patients. This retrospective study examined dual pressure, autoadjusting PAP modes in chronic, complex insomnia disorder patients.Patients and methods: Chronic insomnia disorder patients (mean [SD] insomnia severity index [ISI] =19.11 [3.34] objectively diagnosed with OSA or UARS and using either autobilevel PAP device or adaptive servoventilation (ASV device after failing CPAP therapy (frequently due to intolerance to pressurized air, poor outcomes, or emergence of CSA were divided into PAP users (≥20 h/wk and partial users (<20 h/wk for comparison. Subjective and objective baseline and follow-up measures were analyzed.Results: Of the 302 complex insomnia patients, PAP users (n=246 averaged 6.10 (1.78 nightly hours and 42.71 (12.48 weekly hours and partial users (n=56 averaged 1.67 (0.76 nightly hours and 11.70 (5.31 weekly hours. For mean (SD decreases in total ISI scores, a significant (group × time interaction was observed (F[1,300]=13.566; P<0.0001 with PAP users (–7.59 [5.92]; d=1.63 showing superior results to partial users (-4.34 [6.13]; d=0.81. Anecdotally, patients reported better tolerability with advanced PAP

  9. Treatment of presumed acute cardiogenic pulmonary oedema in an ambulance system by nurses using Boussignac continuous positive airway pressure

    NARCIS (Netherlands)

    Dieperink, Willem; Weelink, E. E. M.; van der Horst, I. C. C.; de Vos, R.; Jaarsma, T.; Aarts, L. P. H. J.; Zijlstra, F.; Nijsten, M. W. N.

    Background: Early initiation of continuous positive airway pressure (CPAP) applied by face mask benefits patients with acute cardiogenic pulmonary oedema (ACPE). The simple disposable Boussignac CPAP (BCPAP) has been used in ambulances by physicians. In the Netherlands, ambulances are manned by

  10. Airway basement membrane perimeter in human airways is not a constant; potential implications for airway remodeling in asthma.

    Science.gov (United States)

    McParland, Brent E; Paré, Peter D; Johnson, Peter R A; Armour, Carol L; Black, Judith L

    2004-08-01

    Many studies that demonstrate an increase in airway smooth muscle in asthmatic patients rely on the assumption that bronchial internal perimeter (P(i)) or basement membrane perimeter (P(bm)) is a constant, i.e., not affected by fixation pressure or the degree of smooth muscle shortening. Because it is the basement membrane that has been purported to be the indistensible structure, this study examines the assumption that P(bm) is not affected by fixation pressure. P(bm) was determined for the same human airway segment (n = 12) fixed at distending pressures of 0 cmH(2)O and 21 cmH(2)O in the absence of smooth muscle tone. P(bm) for the segment fixed at 0 cmH(2)O was determined morphometrically, and the P(bm) for the same segment, had the segment been fixed at 21 cmH(2)O, was predicted from knowing the luminal volume and length of the airway when distended to 21 cmH(2)O (organ bath-derived P(i)). To ensure an accurate transformation of the organ bath-derived P(i) value to a morphometry-derived P(bm) value, had the segment been fixed at 21 cmH(2)O, the relationship between organ bath-derived P(i) and morphometry-derived P(bm) was determined for five different bronchial segments distended to 21 cmH(2)O and fixed at 21 cmH(2)O (r(2) = 0.99, P < 0.0001). Mean P(bm) for bronchial segments fixed at 0 cmH(2)O was 9.4 +/- 0.4 mm, whereas mean predicted P(bm), had the segments been fixed at 21 cmH(2)O, was 14.1 +/- 0.5 mm (P < 0.0001). This indicates that P(bm) is not a constant when isolated airway segments without smooth muscle tone are fixed distended to 21 cmH(2)O. The implication of these results is that the increase in smooth muscle mass in asthma may have been overestimated in some previous studies. Therefore, further studies are required to examine the potential artifact using whole lungs with and without abolition of airway smooth muscle tone and/or inflation.

  11. Chronic adaptations of lung function in breath-hold diving fishermen

    Directory of Open Access Journals (Sweden)

    Cristiane Diniz

    2014-04-01

    Full Text Available Objectives: The aim of this study was to verify and analyze the existence of chronic adaptations of lung function in freediving fishermen whose occupation is artisanal fishing. Material and Methods: This was a cross-sectional study involving 11 breath-hold diving fishermen and 10 non-breath-hold diving fishermen (control from the village of Bitupitá in the municipality of Barroquinha (Ceará - Brazil. Anthropometric measurements, chest and abdominal circumferences as well as spirometric and respiratory muscle strength tests were conducted according to the specifications of the American Thoracic Society/European Respiratory Society (ATS/ERS. In order to compare the measured values versus the predicted values, Student t test was used in the case of parametric test and Wilcoxon test in the case of nonparametric test. To compare the inter-group means Student t test was used for parametric test and Mann-Whitney test for the nonparametric one. The level of significance was set at α = 5%. Results: The forced vital capacity (FVC (4.9±0.6 l vs. 4.3±0.4 l and forced expiratory volume in 1 s (FEV1 (4.0±0.5 l vs. 3.6±0.3 l were, respectively, higher in the group of divers compared to the control group (p ≤ 0.05. Furthermore, in the group of free divers, the measured FVC, FEV1 and FEV1/FVC ratios were significantly greater than the predicted ones. No differences were found between the measured respiratory pressures. Conclusions: These results indicate that breath-hold diving seems to produce chronic adaptations of the respiratory system, resulting in elevated lung volumes with no airway obstruction.

  12. Optimization of sampling parameters for standardized exhaled breath sampling.

    Science.gov (United States)

    Doran, Sophie; Romano, Andrea; Hanna, George B

    2017-09-05

    The lack of standardization of breath sampling is a major contributing factor to the poor repeatability of results and hence represents a barrier to the adoption of breath tests in clinical practice. On-line and bag breath sampling have advantages but do not suit multicentre clinical studies whereas storage and robust transport are essential for the conduct of wide-scale studies. Several devices have been developed to control sampling parameters and to concentrate volatile organic compounds (VOCs) onto thermal desorption (TD) tubes and subsequently transport those tubes for laboratory analysis. We conducted three experiments to investigate (i) the fraction of breath sampled (whole vs. lower expiratory exhaled breath); (ii) breath sample volume (125, 250, 500 and 1000ml) and (iii) breath sample flow rate (400, 200, 100 and 50 ml/min). The target VOCs were acetone and potential volatile biomarkers for oesophago-gastric cancer belonging to the aldehyde, fatty acids and phenol chemical classes. We also examined the collection execution time and the impact of environmental contamination. The experiments showed that the use of exhaled breath-sampling devices requires the selection of optimum sampling parameters. The increase in sample volume has improved the levels of VOCs detected. However, the influence of the fraction of exhaled breath and the flow rate depends on the target VOCs measured. The concentration of potential volatile biomarkers for oesophago-gastric cancer was not significantly different between the whole and lower airway exhaled breath. While the recovery of phenols and acetone from TD tubes was lower when breath sampling was performed at a higher flow rate, other VOCs were not affected. A dedicated 'clean air supply' overcomes the contamination from ambient air, but the breath collection device itself can be a source of contaminants. In clinical studies using VOCs to diagnose gastro-oesophageal cancer, the optimum parameters are 500mls sample volume

  13. Design of Wearable Breathing Sound Monitoring System for Real-Time Wheeze Detection

    Directory of Open Access Journals (Sweden)

    Shih-Hong Li

    2017-01-01

    Full Text Available In the clinic, the wheezing sound is usually considered as an indicator symptom to reflect the degree of airway obstruction. The auscultation approach is the most common way to diagnose wheezing sounds, but it subjectively depends on the experience of the physician. Several previous studies attempted to extract the features of breathing sounds to detect wheezing sounds automatically. However, there is still a lack of suitable monitoring systems for real-time wheeze detection in daily life. In this study, a wearable and wireless breathing sound monitoring system for real-time wheeze detection was proposed. Moreover, a breathing sounds analysis algorithm was designed to continuously extract and analyze the features of breathing sounds to provide the objectively quantitative information of breathing sounds to professional physicians. Here, normalized spectral integration (NSI was also designed and applied in wheeze detection. The proposed algorithm required only short-term data of breathing sounds and lower computational complexity to perform real-time wheeze detection, and is suitable to be implemented in a commercial portable device, which contains relatively low computing power and memory. From the experimental results, the proposed system could provide good performance on wheeze detection exactly and might be a useful assisting tool for analysis of breathing sounds in clinical diagnosis.

  14. Evaluating the Effect of Flow and Interface Type on Pressures Delivered With Bubble CPAP in a Simulated Model.

    Science.gov (United States)

    Bailes, Stephanie A; Firestone, Kimberly S; Dunn, Diane K; McNinch, Neil L; Brown, Miraides F; Volsko, Teresa A

    2016-03-01

    Bubble CPAP, used for spontaneously breathing infants to avoid intubation or postextubation support, can be delivered with different interface types. This study compared the effect that interfaces had on CPAP delivery. We hypothesized that there would be no difference between set and measured levels between interface types. A validated preterm infant nasal airway model was attached to the ASL 5000 breathing simulator. The simulator was programmed to deliver active breathing of a surfactant-deficient premature infant with breathing frequency at 70 breaths/min inspiratory time of 0.30 s, resistance of 150 cm H2O/L/s, compliance of 0.5 mL/cm H2O, tidal volume of 5 mL, and esophageal pressure of -10 cm H2O. Nasal CPAP prongs, size 4030, newborn and infant RAM cannulas were connected to a nasal airway model and a bubble CPAP system. CPAP levels were set at 4, 5, 6, 7, 8, and 9 cm H2O with flows of 6, 8, and 10 L/min each. Measurements were recorded after 1 min of stabilization. The analysis was performed using SAS 9.4. The Kolmogorov-Smirnov test assessed normality of the data. The Friedman test was used to compare non-normally distributed repeated measures. The Wilcoxon signed-rank test was used to conduct post hoc analysis. All tests were 2-sided, and P values of CPAP levels, 4-6 cm H2O, measured CPAP dropped precipitously with the nasal prongs with the highest flow setting. At higher CPAP levels, 7-9 cm H2O measured CPAP concomitantly increased as the flow setting increased. Statistically significant differences in set and measured CPAP occurred for all devices across all CPAP levels, with the measured CPAP less than set for all conditions, P CPAP. The concomitant drop in measured pressure with high and low flows could be attributed to increased resistance to spontaneous breathing or insufficient flow to meet inspiratory demand. Clinicians should be aware of the effect that the interface and flow have on CPAP delivery. Copyright © 2016 by Daedalus Enterprises.

  15. TRPM8 mechanism of autonomic nerve response to cold in respiratory airway

    Directory of Open Access Journals (Sweden)

    Wang Cong-Yi

    2008-06-01

    Full Text Available Abstract Breathing cold air without proper temperature exchange can induce strong respiratory autonomic responses including cough, airway constriction and mucosal secretion, and can exacerbate existing asthma conditions and even directly trigger an asthma attack. Vagal afferent fiber is thought to be involved in the cold-induced respiratory responses through autonomic nerve reflex. However, molecular mechanisms by which vagal afferent fibers are excited by cold remain unknown. Using retrograde labeling, immunostaining, calcium imaging, and electrophysiological recordings, here we show that a subpopulation of airway vagal afferent nerves express TRPM8 receptors and that activation of TRPM8 receptors by cold excites these airway autonomic nerves. Thus activation of TRPM8 receptors may provoke autonomic nerve reflex to increase airway resistance. This putative autonomic response may be associated with cold-induced exacerbation of asthma and other pulmonary disorders, making TRPM8 receptors a possible target for prevention of cold-associated respiratory disorders.

  16. Features of motivation of the crewmembers in an enclosed space at atmospheric pressure changes during breathing inert gases.

    Science.gov (United States)

    Komarevcev, Sergey

    Since the 1960s, our psychologists are working on experimenting with small groups in isolation .It was associated with the beginning of spaceflight and necessity to study of human behaviors in ways different from the natural habitat of man .Those, who study human behavior especially in isolation, know- that the behavior in isolation markedly different from that in the natural situations. It associated with the development of new, more adaptive behaviors (1) What are the differences ? First of all , isolation is achieved by the fact ,that the group is in a closed space. How experiments show - the crew members have changed the basic personality traits, such as motivation Statement of the problem and methods. In our experimentation we were interested in changing the features of human motivation (strength, stability and direction of motivation) in terms of a closed group in the modified atmosphere pressure and breathing inert gases. Also, we were interested in particular external and internal motivation of the individual in the circumstances. To conduct experimentation , we used an experimental barocomplex GVK -250 , which placed a group of six mans. A task was to spend fifteen days in isolation on barokomplex when breathing oxigen - xenon mixture of fifteen days in isolation on the same complex when breathing oxygen- helium mixture and fifteen days of isolation on the same complex when breathing normal air All this time, the subjects were isolated under conditions of atmospheric pressure changes , closer to what you normally deal divers. We assumed that breathing inert mixtures can change the strength and stability , and with it , the direction and stability of motivation. To check our results, we planned on using the battery of psychological techniques : 1. Schwartz technique that measures personal values and behavior in society, DORS procedure ( measurement of fatigue , monotony , satiety and stress ) and riffs that give the test once a week. Our assumption is

  17. Breathing circuit compliance and accuracy of displayed tidal volume during pressure-controlled ventilation of infants: A quality improvement project.

    Science.gov (United States)

    Glenski, Todd A; Diehl, Carrie; Clopton, Rachel G; Friesen, Robert H

    2017-09-01

    Anesthesia machines have evolved to deliver desired tidal volumes more accurately by measuring breathing circuit compliance during a preuse self-test and then incorporating the compliance value when calculating expired tidal volume. The initial compliance value is utilized in tidal volume calculation regardless of whether the actual compliance of the breathing circuit changes during a case, as happens when corrugated circuit tubing is manually expanded after the preuse self-test but before patient use. We noticed that the anesthesia machine preuse self-test was usually performed on nonexpanded pediatric circuit tubing, and then the breathing circuit was subsequently expanded for clinical use. We aimed to demonstrate that performing the preuse self-test in that manner could lead to incorrectly displayed tidal volume on the anesthesia machine monitor. The goal of this quality improvement project was to change the usual practice and improve the accuracy of displayed tidal volume in infants undergoing general anesthesia. There were four stages of the project: (i) gathering baseline data about the performance of the preuse self-test and using infant and adult test lungs to measure discrepancies of displayed tidal volumes when breathing circuit compliance was changed after the initial preuse self-test; (ii) gathering clinical data during pressure-controlled ventilation comparing anesthesia machine displayed tidal volume with actual spirometry tidal volume in patients less than 10 kg before (machine preuse self-test performed while the breathing circuit was nonexpanded) and after an intervention (machine preuse self-test performed after the breathing circuit was fully expanded); (iii) performing department-wide education to help implement practice change; (iv) gathering postintervention data to determine the prevalence of proper machine preuse self-test. At constant pressure-controlled ventilation through fully expanded circuit tubing, displayed tidal volume was 83

  18. Predicting uptake of continuous positive airway pressure (CPAP) therapy in obstructive sleep apnoea (OSA)

    DEFF Research Database (Denmark)

    Skinner, Timothy; McNeil, Lindsay; Olaithe, Michelle

    2013-01-01

    diagnosed with OSA. Epworth sleepiness scale (ESS), Fatigue Severity Scale, Depression Anxiety Stress Scale and Illness Perception Questionnaire-Revised (IPQ-R) were administered at time of sleep study. These, patient demographics and sleep study variables were used to determine factors predicting patient......Purpose: Obstructive sleep apnoea (OSA) is a common disorder, for which continuous positive airway pressure (CPAP) therapy is a standard treatment. Despite its well-established efficacy, many patients choose not to initiate CPAP treatment. The present study investigated the degree to which...

  19. [Airway humidification practices in Chilean intensive care units].

    Science.gov (United States)

    Retamal, Jaime; Castillo, Juan; Bugedo, Guillermo; Bruhn, Alejandro

    2012-11-01

    In patients with an artificial airway, inspired gases can be humidified and heated using a passive (heat and moisture exchange filter - HMEF), or an active system (heated humidifier). To assess how humidification is carried out and what is the usual clinical practice in this field in Chilean intensive care units (ICUs). A specific survey to evaluate humidification system features as well as caregivers' preferences regarding humidification systems, was carried out on the same day in all Chilean ICUs. Fifty-five ICUs were contacted and 44 of them completed the survey. From a total of 367 patients, 254 (69%) required humidification because they were breathing through an artificial airway. A heated humidifier was employed only in 12 patients (5%). Forty-three ICUs (98%) used HMEF as their routine humidification system. In 52% of surveyed ICUs, heated humidifiers were not available. In Chile the main method to humidify and heat inspired gases in patients with an artificial airway is the HMEF. Although there are clear indications for the use of heated humidifiers, they are seldom employed.

  20. Aspergillus spp. colonization in exhaled breath condensate of lung cancer patients from Puglia Region of Italy.

    Science.gov (United States)

    Carpagnano, Giovanna E; Lacedonia, Donato; Palladino, Grazia Pia; Logrieco, Giuseppe; Crisetti, Elisabetta; Susca, Antonia; Logrieco, Antonio; Foschino-Barbaro, Maria P

    2014-02-18

    Airways of lung cancer patients are often colonized by fungi. Some of these colonizing fungi, under particular conditions, produce cancerogenic mycotoxins. Given the recent interest in the infective origin of lung cancer, with this preliminary study we aim to give our small contribution to this field of research by analysing the fungal microbiome of the exhaled breath condensate of lung cancer patients from Puglia, a region of Italy. We enrolled 43 lung cancer patients and 21 healthy subjects that underwent exhaled breath condensate and bronchial brushing collection. The fungal incidence and nature of sample collected were analysed by using a selected media for Aspergillus species. For the first time we were able to analyse the fungal microbioma of the exhaled breath condensate. 27.9% of lung cancer patients showed a presence of Aspergillus niger, or A. ochraceus or Penicillium ssp. while none of the healthy subjects did so. The results confirmed the high percentage of fungal colonization of the airways of lung cancer patients from Puglia, suggesting the need to conduct further analyses in this field in order to evaluate the exact pathogenetic role of these fungi in lung cancer as well as to propose efficient, empirical therapy.

  1. Randomised trial of elective continuous positive airway pressure (CPAP) compared with rescue CPAP after extubation

    OpenAIRE

    Robertson, N; Hamilton, P

    1998-01-01

    AIM—To determine if a weaning regimen on flow driver continuous positive airway pressure (CPAP) would decrease the number of ventilator days but increase the number of CPAP days when compared with a rescue regimen.
METHODS—Fifty eight babies of 24-32 weeks gestation with respiratory distress syndrome (RDS) were studied prospectively. After extubation they were randomly allocated to receive CPAP for 72 hours (n=29) according to a weaning regimen, or were placed in headbox ...

  2. Electronic Nose Breathprints Are Independent of Acute Changes in Airway Caliber in Asthma

    Directory of Open Access Journals (Sweden)

    Jan van der Maten

    2010-10-01

    Full Text Available Molecular profiling of exhaled volatile organic compounds (VOC by electronic nose technology provides breathprints that discriminate between patients with different inflammatory airway diseases, such as asthma and COPD. However, it is unknown whether this is determined by differences in airway caliber. We hypothesized that breathprints obtained by electronic nose are independent of acute changes in airway caliber in asthma. Ten patients with stable asthma underwent methacholine provocation (Visit 1 and sham challenge with isotonic saline (Visit 2. At Visit 1, exhaled air was repetitively collected pre-challenge, after reaching the provocative concentration (PC20 causing 20% fall in forced expiratory volume in 1 second (FEV1 and after subsequent salbutamol inhalation. At Visit 2, breath was collected pre-challenge, post-saline and post-salbutamol. At each occasion, an expiratory vital capacity was collected after 5 min of tidal breathing through an inspiratory VOC-filter in a Tedlar bag and sampled by electronic nose (Cyranose 320. Breathprints were analyzed with principal component analysis and individual factors were compared with mixed model analysis followed by pairwise comparisons. Inhalation of methacholine led to a 30.8 ± 3.3% fall in FEV1 and was followed by a significant change in breathprint (p = 0.04. Saline inhalation did not induce a significant change in FEV1, but altered the breathprint (p = 0.01. However, the breathprint obtained after the methacholine provocation was not significantly different from that after saline challenge (p = 0.27. The molecular profile of exhaled air in patients with asthma is altered by nebulized aerosols, but is not affected by acute changes in airway caliber. Our data demonstrate that breathprints by electronic nose are not confounded by the level of airway obstruction.

  3. Pressure support ventilation vs Continuous positive airway pressure for treating of acute cardiogenic pulmonary edema: A pilot study.

    Science.gov (United States)

    Pagano, Antonio; Numis, Fabio G; Rosato, Valerio; Russo, Teresa; Porta, Giovanni; Bosso, Giorgio; Serra, Claudia; Masarone, Mario; Visone, Giuseppe; Paladino, Fiorella

    2018-04-24

    Non-invasive ventilation is usually adopted as a support to medical therapy in patients with acute pulmonary edema, but which modality between Pressure Support Ventilation (PSV) and Continuous Positive Airway Pressure (CPAP) has better favourable effects is not been yet well known. Aim of this observational study was to provide data on these different non-invasive ventilation modalities in the management of acute cardiogenic pulmonary edema. One-hundred-fifty-three patients consecutively admitted to the Emergency Room of two different Center were enrolled and randomly assigned to CPAP or PSV. Data relative to mortality, need of endotracheal intubation, sequential blood gas analysis were compared. Furthermore, there were no significant differences regarding mortality in the two groups, but patients treated with PSV had a significant lower rate of endotracheal intubation and a higher improvement of blood gas analyses parameters. In conclusion, our data support only a slight advantage in favour to PSV versus CPAP. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Fractionated breath condensate sampling: H2O2 concentrations of the alveolar fraction may be related to asthma control in children

    Directory of Open Access Journals (Sweden)

    Trischler Jordis

    2012-02-01

    Full Text Available Abstract Background Asthma is a chronic inflammatory disease of the airways but recent studies have shown that alveoli are also subject to pathophysiological changes. This study was undertaken to compare hydrogen peroxide (H2O2 concentrations in different parts of the lung using a new technique of fractioned breath condensate sampling. Methods In 52 children (9-17 years, 32 asthmatic patients, 20 controls measurements of exhaled nitric oxide (FENO, lung function, H2O2 in exhaled breath condensate (EBC and the asthma control test (ACT were performed. Exhaled breath condensate was collected in two different fractions, representing mainly either the airways or the alveoli. H2O2 was analysed in the airway and alveolar fractions and compared to clinical parameters. Results The exhaled H2O2 concentration was significantly higher in the airway fraction than in the alveolar fraction comparing each single pair (p = 0.003, 0.032 and 0.040 for the whole study group, the asthmatic group and the control group, respectively. Asthma control, measured by the asthma control test (ACT, correlated significantly with the H2O2 concentrations in the alveolar fraction (r = 0.606, p = 0.004 but not with those in the airway fraction in the group of children above 12 years. FENO values and lung function parameters did not correlate to the H2O2 concentrations of each fraction. Conclusion The new technique of fractionated H2O2 measurement may differentiate H2O2 concentrations in different parts of the lung in asthmatic and control children. H2O2 concentrations of the alveolar fraction may be related to the asthma control test in children.

  5. Modeling water vapor and heat transfer in the normal and the intubated airways.

    Science.gov (United States)

    Tawhai, Merryn H; Hunter, Peter J

    2004-04-01

    Intubation of the artificially ventilated patient with an endotracheal tube bypasses the usual conditioning regions of the nose and mouth. In this situation any deficit in heat or moisture in the air is compensated for by evaporation and thermal transfer from the pulmonary airway walls. To study the dynamics of heat and water transport in the intubated airway, a coupled system of nonlinear equations is solved in airway models with symmetric geometry and anatomically based geometry. Radial distribution of heat, water vapor, and velocity in the airway are described by power-law equations. Solution of the time-dependent system of equations yields dynamic airstream and mucosal temperatures and air humidity. Comparison of model results with two independent experimental studies in the normal and intubated airway shows a close correlation over a wide range of minute ventilation. Using the anatomically based model a range of spatially distributed temperature paths is demonstrated, which highlights the model's ability to predict thermal behavior in airway regions currently inaccessible to measurement. Accurate representation of conducting airway geometry is shown to be necessary for simulating mouth-breathing at rates between 15 and 100 l x min(-1), but symmetric geometry is adequate for the low minute ventilation and warm inspired air conditions that are generally supplied to the intubated patient.

  6. Grain Entrapment Pressure on the Torso: Can You Breathe while Buried in Grain?

    Science.gov (United States)

    Moore, Kevin G; Jones, Carol L

    2017-04-26

    The pressure applied to the chest and back of a simulated grain entrapment victim was measured. Pressure sensors were attached to the chest and back of a manikin that was buried in grain in the vertical position. Measurements were made in four grain types at four grain depths ranging from the top of the manikin's shoulders to 0.61 m (24 in.) over the head. The pressure ranged from 1.6 to 4.0 kPa (0.23 to 0.57 psi). Based on available physiological information, this amount of pressure is unlikely to limit the respiration of an otherwise healthy adult male victim. However, other factors, such as the victim's age, gender, and body position in the grain, may influence respiration. The aspiration of grain appears to be the most likely asphyxiation risk during grain bin entrapment. Entering a grain storage bin is inherently dangerous, and Occupational Safety and Health Administration (OSHA) guidelines for permit-required confined spaces and grain handling facilities must be followed. Due to the risk of grain aspiration during engulfment, the development of safety equipment that could help protect the airway of a victim should be investigated. Copyright© by the American Society of Agricultural Engineers.

  7. Increased respiratory neural drive and work of breathing in exercise-induced laryngeal obstruction.

    Science.gov (United States)

    Walsted, Emil S; Faisal, Azmy; Jolley, Caroline J; Swanton, Laura L; Pavitt, Matthew J; Luo, Yuan-Ming; Backer, Vibeke; Polkey, Michael I; Hull, James H

    2018-02-01

    Exercise-induced laryngeal obstruction (EILO), a phenomenon in which the larynx closes inappropriately during physical activity, is a prevalent cause of exertional dyspnea in young individuals. The physiological ventilatory impact of EILO and its relationship to dyspnea are poorly understood. The objective of this study was to evaluate exercise-related changes in laryngeal aperture on ventilation, pulmonary mechanics, and respiratory neural drive. We prospectively evaluated 12 subjects (6 with EILO and 6 healthy age- and gender-matched controls). Subjects underwent baseline spirometry and a symptom-limited incremental exercise test with simultaneous and synchronized recording of endoscopic video and gastric, esophageal, and transdiaphragmatic pressures, diaphragm electromyography, and respiratory airflow. The EILO and control groups had similar peak work rates and minute ventilation (V̇e) (work rate: 227 ± 35 vs. 237 ± 35 W; V̇e: 103 ± 20 vs. 98 ± 23 l/min; P > 0.05). At submaximal work rates (140-240 W), subjects with EILO demonstrated increased work of breathing ( P respiratory neural drive ( P respiratory mechanics and diaphragm electromyography with endoscopic video, we demonstrate, for the first time, increased work of breathing and respiratory neural drive in association with the development of EILO. Future detailed investigations are now needed to understand the role of upper airway closure in causing exertional dyspnea and exercise limitation. NEW & NOTEWORTHY Exercise-induced laryngeal obstruction is a prevalent cause of exertional dyspnea in young individuals; yet, how laryngeal closure affects breathing is unknown. In this study we synchronized endoscopic video with respiratory physiological measurements, thus providing the first detailed commensurate assessment of respiratory mechanics and neural drive in relation to laryngeal closure. Laryngeal closure was associated with increased work of breathing and respiratory neural drive preceded by an

  8. Small airways dysfunction in long-term survivors of pediatric stem cell transplantation

    DEFF Research Database (Denmark)

    Uhlving, Hilde Hylland; Mathiesen, Sidsel; Buchvald, Frederik

    2015-01-01

    BACKGROUND: Chronic graft-versus-host disease (cGvHD) in the lungs is a life-threatening complication of allogeneic hematopoietic stem cell transplantation (HSCT). Pulmonary cGvHD is initiated in the peripheral airways, and diagnosis may be delayed by low sensitivity of standard pulmonary function...... performed spirometry, whole-body plethysmography and MBWN2 . From MBWN2 the lung clearance index (LCI) and indices reflecting ventilation inhomogeneity arising close to the acinar lung zone (Sacin ) and in the conductive airway zone (Scond ) were derived. Subjective respiratory morbidity was assessed using...... tests. Multiple breath nitrogen washout (MBWN2 ) is a promising, sensitive method to assess small airways function. This is the first report on MBWN2 in survivors of pediatric HSCT. METHODS: This cross-sectional study undertaken 3-10 years post-HSCT, included 64 patients and 64 matched controls who all...

  9. Gadolinium prevents high airway pressure-induced permeability increases in isolated rat lungs.

    Science.gov (United States)

    Parker, J C; Ivey, C L; Tucker, J A

    1998-04-01

    To determine the initial signaling event in the vascular permeability increase after high airway pressure injury, we compared groups of lungs ventilated at different peak inflation pressures (PIPs) with (gadolinium group) and without (control group) infusion of 20 microM gadolinium chloride, an inhibitor of endothelial stretch-activated cation channels. Microvascular permeability was assessed by using the capillary filtration coefficient (Kfc), a measure of capillary hydraulic conductivity. Kfc was measured after ventilation for 30-min periods with 7, 20, and 30 cmH2O PIP with 3 cmH2O positive end-expiratory pressure and with 35 cmH2O PIP with 8 cmH2O positive end-expiratory pressure. In control lungs, Kfc increased significantly to 1.8 and 3.7 times baseline after 30 and 35 cmH2O PIP, respectively. In the gadolinium group, Kfc was unchanged from baseline (0.060 +/- 0.010 ml . min-1 . cmH2O-1 . 100 g-1) after any PIP ventilation period. Pulmonary vascular resistance increased significantly from baseline in both groups before the last Kfc measurement but was not different between groups. These results suggest that microvascular permeability is actively modulated by a cellular response to mechanical injury and that stretch-activated cation channels may initiate this response through increases in intracellular calcium concentration.

  10. Relationships between hippocampal activity and breathing patterns

    DEFF Research Database (Denmark)

    Harper, R M; Poe, G R; Rector, D M

    1998-01-01

    Single cell discharge, EEG activity, and optical changes accompanying alterations in breathing patterns, as well as the knowledge that respiratory musculature is heavily involved in movement and other behavioral acts, implicate hippocampal regions in some aspects of breathing control. The control...... is unlikely to reside in oscillatory breathing movements, because such patterns emerge in preparations retaining only the medulla (and perhaps only the spinal cord). However, momentary changes in breathing patterns induced by affect, startle, whole-body movement changes, or compensatory ventilatory changes...... of hippocampal contributions to breathing control should be viewed in the context that significant interactions exist between blood pressure changes and ventilation, and that modest breathing challenges, such as exposure to hypercapnia or to increased resistive loads, bring into action a vast array of brain...

  11. Simulation of late inspiratory rise in airway pressure during pressure support ventilation.

    Science.gov (United States)

    Yu, Chun-Hsiang; Su, Po-Lan; Lin, Wei-Chieh; Lin, Sheng-Hsiang; Chen, Chang-Wen

    2015-02-01

    Late inspiratory rise in airway pressure (LIRAP, Paw/ΔT) caused by inspiratory muscle relaxation or expiratory muscle contraction is frequently seen during pressure support ventilation (PSV), although the modulating factors are unknown. We investigated the effects of respiratory mechanics (normal, obstructive, restrictive, or mixed), inspiratory effort (-2, -8, or -15 cm H2O), flow cycle criteria (5-40% peak inspiratory flow), and duration of inspiratory muscle relaxation (0.18-0.3 s) on LIRAP during PSV using a lung simulator and 4 types of ventilators. LIRAP occurred with all lung models when inspiratory effort was medium to high and duration of inspiratory muscle relaxation was short. The normal lung model was associated with the fastest LIRAP, whereas the obstructive lung model was associated with the slowest. Unless lung mechanics were normal or mixed, LIRAP was unlikely to occur when inspiratory effort was low. Different ventilators were also associated with differences in LIRAP speed. Except for within the restrictive lung model, changes in flow cycle level did not abolish LIRAP if inspiratory effort was medium to high. Increased duration of inspiratory relaxation also led to the elimination of LIRAP. Simulation of expiratory muscle contraction revealed that LIRAP occurred only when expiratory muscle contraction occurred sometime after the beginning of inspiration. Our simulation study reveals that both respiratory resistance and compliance may affect LIRAP. Except for under restrictive lung conditions, LIRAP is unlikely to be abolished by simply lowering flow cycle criteria when inspiratory effort is strong and relaxation time is rapid. LIRAP may be caused by expiratory muscle contraction when it occurs during inspiration. Copyright © 2015 by Daedalus Enterprises.

  12. All-cause mortality from obstructive sleep apnea in male and female patients with and without continuous positive airway pressure treatment

    DEFF Research Database (Denmark)

    Jennum, Poul; Tønnesen, Philip; Ibsen, Rikke

    2015-01-01

    BACKGROUND: More information is needed about the effect on mortality of continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA), especially in women. METHODS: We employed a historical cohort study design, using data from 25,389 patients with a diagnosis of OSA...

  13. Wire-guided (Seldinger technique intubation through a face mask in urgent, difficult and grossly distorted airways

    Directory of Open Access Journals (Sweden)

    Jake M Heier

    2012-01-01

    Full Text Available We report two cases of successful urgent intubation using a Seldinger technique for airway management through an anesthesia facemask, while maintaining ventilation in patients with difficult airways and grossly distorted airway anatomy. In both cases, conventional airway management techniques were predicted to be difficult or impossible, and a high likelihood for a surgical airway was present. This technique was chosen as it allows tracheal tube placement through the nares during spontaneous ventilation with the airway stented open and oxygen delivery with either continuous positive airway pressure and/or pressure support ventilation. This unhurried technique may allow intubation when other techniques are unsuitable, while maintaining control of the airway.

  14. Effects of tidal volume on work of breathing during lung-protective ventilation in patients with acute lung injury and acute respiratory distress syndrome.

    Science.gov (United States)

    Kallet, Richard H; Campbell, Andre R; Dicker, Rochelle A; Katz, Jeffrey A; Mackersie, Robert C

    2006-01-01

    To assess the effects of step-changes in tidal volume on work of breathing during lung-protective ventilation in patients with acute lung injury (ALI) or the acute respiratory distress syndrome (ARDS). Prospective, nonconsecutive patients with ALI/ARDS. Adult surgical, trauma, and medical intensive care units at a major inner-city, university-affiliated hospital. Ten patients with ALI/ARDS managed clinically with lung-protective ventilation. Five patients were ventilated at a progressively smaller tidal volume in 1 mL/kg steps between 8 and 5 mL/kg; five other patients were ventilated at a progressively larger tidal volume from 5 to 8 mL/kg. The volume mode was used with a flow rate of 75 L/min. Minute ventilation was maintained constant at each tidal volume setting. Afterward, patients were placed on continuous positive airway pressure for 1-2 mins to measure their spontaneous tidal volume. Work of breathing and other variables were measured with a pulmonary mechanics monitor (Bicore CP-100). Work of breathing progressively increased (0.86 +/- 0.32, 1.05 +/- 0.40, 1.22 +/- 0.36, and 1.57 +/- 0.43 J/L) at a tidal volume of 8, 7, 6, and 5 mL/kg, respectively. In nine of ten patients there was a strong negative correlation between work of breathing and the ventilator-to-patient tidal volume difference (R = -.75 to -.998). : The ventilator-delivered tidal volume exerts an independent influence on work of breathing during lung-protective ventilation in patients with ALI/ARDS. Patient work of breathing is inversely related to the difference between the ventilator-delivered tidal volume and patient-generated tidal volume during a brief trial of unassisted breathing.

  15. Unilateral Hypoglossal Nerve Palsy after Use of the Laryngeal Mask Airway Supreme

    Directory of Open Access Journals (Sweden)

    Kenichi Takahoko

    2014-01-01

    Full Text Available Purpose. Hypoglossal nerve palsy after use of the laryngeal mask airway (LMA is an exceptionally rare complication. We present the first case of unilateral hypoglossal nerve palsy after use of the LMA Supreme. Clinical Features. A healthy 67-year-old female was scheduled for a hallux valgus correction under general anesthesia combined with femoral and sciatic nerve blocks. A size 4 LMA Supreme was inserted successfully at the first attempt and the cuff was inflated with air at an intracuff pressure of 60 cmH2O using cuff pressure gauge. Anesthesia was maintained with oxygen, nitrous oxide (67%, and sevoflurane under spontaneous breathing. The surgery was uneventful and the duration of anesthesia was two hours. The LMA was removed as the patient woke and there were no immediate postoperative complications. The next morning, the patient complained of dysarthria and dysphasia. These symptoms were considered to be caused by the LMA compressing the nerve against the hyoid bone. Conservative treatment was chosen and the paralysis recovered completely after 5 months. Conclusion. Hypoglossal nerve injury may occur despite correct positioning of the LMA under the appropriate intracuff pressure. A follow-up period of at least 6 months should be taken into account for the recovery.

  16. Airway Clearance Techniques (ACTs)

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    Full Text Available ... Clinician Career Development Awards Clinician Training Awards Mutation Analysis Program Network News Network News: March 2018 Network ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

  17. Airway Clearance Techniques (ACTs)

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    Full Text Available ... today. ANNUAL FUND Become a Corporate Supporter Cause Marketing Make a Charitable Gift Our Corporate Supporters Workplace ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

  18. Airway Clearance Techniques (ACTs)

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    Full Text Available ... Clinician Career Development Awards Clinician Training Awards Mutation Analysis Program Network News Network News: June 2018 Network ... for airway clearance. Facebook Twitter Email More Related Content Medications Autogenic Drainage Positive Expiratory Pressure High-Frequency ...

  19. Airway Clearance Techniques (ACTs)

    Science.gov (United States)

    ... infant or child manage their lung health, watch parents of children with CF and a respiratory therapist talk about the different techniques they use for airway ... Positive Expiratory Pressure High-Frequency Chest Wall Oscillation (the Vest) Follow ...

  20. Bilateral parotitis in a patient under continuous positive airway pressure treatment.

    Science.gov (United States)

    Abdullayev, Ruslan; Saral, Filiz Cosku; Kucukebe, Omer Burak; Sayiner, Hakan Sezgin; Bayraktar, Cem; Akgun, Sadik

    Many conditions such as bacterial and viral infectious diseases, mechanical obstruction due to air and calculi and drugs can cause parotitis. We present a case of unusual bilateral parotitis in a patient under non-invasive continuous positive airway pressure (CPAP) therapy for chronic obstructive pulmonary disease exacerbation in intensive care unit. A 36-year-old patient was admitted to intensive care unit with the diagnosis of chronic obstructive pulmonary disease exacerbation. Antibiotherapy, bronchodilator therapy and non-invasive positive pressure ventilation were applied as treatment regimen. Painless swellings developed on the 3rd day of admission on the right and a day after this on the left parotid glands. Amylase levels were increased and ultrasonographic evaluation revealed bilateral parotitis. No intervention was made and the therapy was continued. The patient was discharged on the 6th day with clinical improvement and regression of parotid swellings without any complications. Parotitis may have occurred after retrograde air flow in the Stensen duct during CPAP application. After the exclusion of possible viral and bacteriological etiologies and possible drug reactions we can focus on this diagnosis. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  1. Work of breathing during lung-protective ventilation in patients with acute lung injury and acute respiratory distress syndrome: a comparison between volume and pressure-regulated breathing modes.

    Science.gov (United States)

    Kallet, Richard H; Campbell, Andre R; Dicker, Rochelle A; Katz, Jeffrey A; Mackersie, Robert C

    2005-12-01

    Pressure-control ventilation (PCV) and pressure-regulated volume-control (PRVC) ventilation are used during lung-protective ventilation because the high, variable, peak inspiratory flow rate (V (I)) may reduce patient work of breathing (WOB) more than the fixed V (I) of volume-control ventilation (VCV). Patient-triggered breaths during PCV and PRVC may result in excessive tidal volume (V(T)) delivery unless the inspiratory pressure is reduced, which in turn may decrease the peak V (I). We tested whether PCV and PRVC reduce WOB better than VCV with a high, fixed peak V (I) (75 L/min) while also maintaining a low V(T) target. Fourteen nonconsecutive patients with acute lung injury or acute respiratory distress syndrome were studied prospectively, using a random presentation of ventilator modes in a crossover, repeated-measures design. A target V(T) of 6.4 + 0.5 mL/kg was set during VCV and PRVC. During PCV the inspiratory pressure was set to achieve the same V(T). WOB and other variables were measured with a pulmonary mechanics monitor (Bicore CP-100). There was a nonsignificant trend toward higher WOB (in J/L) during PCV (1.27 + 0.58 J/L) and PRVC (1.35 + 0.60 J/L), compared to VCV (1.09 + 0.59 J/L). While mean V(T) was not statistically different between modes, in 40% of patients, V(T) markedly exceeded the lung-protective ventilation target during PRVC and PCV. During lung-protective ventilation, PCV and PRVC offer no advantage in reducing WOB, compared to VCV with a high flow rate, and in some patients did not allow control of V(T) to be as precise.

  2. Oral continuous positive airway pressure (CPAP) following nasal injury in a preterm infant.

    Science.gov (United States)

    Carlisle, H R; Kamlin, C O F; Owen, L S; Davis, P G; Morley, C J

    2010-03-01

    Non-invasive respiratory support is increasingly popular but is associated with complications including nasal trauma. The present report describes a novel method of oral continuous positive airway pressure (CPAP) delivery in an extremely premature infant with severe nasal septum erosion. The distal end of a cut down endotracheal tube was passed through a small hole made in the teat of a dummy (infant pacifier) and sutured in place. The dummy was secured in the infant's mouth and CPAP was delivered to the pharynx. The device was well tolerated and the infant was successfully managed using this technique for 48 days, avoiding endotracheal intubation and ventilation.

  3. Pediatric supraglottic airway devices in clinical practice: A prospective observational study.

    Science.gov (United States)

    Kleine-Brueggeney, Maren; Gottfried, Anne; Nabecker, Sabine; Greif, Robert; Book, Malte; Theiler, Lorenz

    2017-09-02

    Supraglottic airway devices (SGA) are commonly used in pediatric anesthesia and serve as primary or back-up devices for difficult airway management. Most SGA are marketed without proper clinical evaluation. The purpose of this study was to evaluate the performance of the pediatric LMA Supreme™, Air-Q® and Ambu® Aura-i™. This prospective observational study was performed at Bern University Hospital, Switzerland. With ethics committee approval and a waiver for written informed consent 240 children undergoing elective surgery with an ASA class I-III and a weight of 5-30 kg were included. Three different pediatric supraglottic airway devices were assessed: The LMA Supreme™, Air-Q® and Ambu® Aura-i™. Primary outcome parameter was airway leak pressure. Secondary outcome parameters included first attempt and overall success rate, insertion time, fiberoptic view through the SGA, and adverse events. The primary hypothesis was that the mean airway leak pressure of each tested SGA was 20 cmH 2 O ± 10%. None of the SGA showed a mean airway leak pressure of 20 cmH 2 O ± 10%, but mean airway leak pressures differed significantly between devices [LMA Supreme™ 18.0 (3.4) cmH 2 O, Air-Q® 15.9 (3.2) cmH 2 O, Ambu® Aura-i™ 17.3 (3.7) cmH 2 O, p < 0.001]. First attempt success rates (LMA Supreme™ 100%, Air-Q® 90%, Ambu® Aura-i™ 91%, p = 0.02) and overall success rates (LMA Supreme™ 100%, Air-Q® 91%, Ambu® Aura-i™ 95%, p = 0.02) also differed significantly. Insertion times ranged from 20 (7) seconds (Air-Q®) to 24 (6) seconds (LMA Supreme™, Airway leak pressures ranged from 16 to 18 cmH 2 O, enabling positive pressure ventilation with all successful SGA. The highest success rates were achieved by the LMA Supreme™, which was also

  4. Potential of Mass Spectrometry in Developing Clinical Laboratory Biomarkers of Nonvolatiles in Exhaled Breath.

    Science.gov (United States)

    Beck, Olof; Olin, Anna-Carin; Mirgorodskaya, Ekaterina

    2016-01-01

    Exhaled breath contains nonvolatile substances that are part of aerosol particles of submicrometer size. These particles are formed and exhaled as a result of normal breathing and contain material from distal airways of the respiratory system. Exhaled breath can be used to monitor biomarkers of both endogenous and exogenous origin and constitutes an attractive specimen for medical investigations. This review summarizes the present status regarding potential biomarkers of nonvolatile compounds in exhaled breath. The field of exhaled breath condensate is briefly reviewed, together with more recent work on more selective collection procedures for exhaled particles. The relation of these particles to the surfactant in the terminal parts of the respiratory system is described. The literature on potential endogenous low molecular weight compounds as well as protein biomarkers is reviewed. The possibility to measure exposure to therapeutic and abused drugs is demonstrated. Finally, the potential future role and importance of mass spectrometry is discussed. Nonvolatile compounds exit the lung as aerosol particles that can be sampled easily and selectively. The clinical applications of potential biomarkers in exhaled breath comprise diagnosis of disease, monitoring of disease progress, monitoring of drug therapy, and toxicological investigations. © 2015 American Association for Clinical Chemistry.

  5. Comparison of manual versus automatic continuous positive airway pressure titration and the development of a predictive equation for therapeutic continuous positive airway pressure in Chinese patients with obstructive sleep apnoea.

    Science.gov (United States)

    Luo, Jiaying; Xiao, Sichang; Qiu, Zhihui; Song, Ning; Luo, Yuanming

    2013-04-01

    Whether the therapeutic nasal continuous positive airway pressure (CPAP) derived from manual titration is the same as derived from automatic titration is controversial. The purpose of this study was to compare the therapeutic pressure derived from manual titration with automatic titration. Fifty-one patients with obstructive sleep apnoea (OSA) (mean apnoea/hypopnoea index (AHI) = 50.6 ± 18.6 events/h) who were newly diagnosed after an overnight full polysomnography and who were willing to accept CPAP as a long-term treatment were recruited for the study. Manual titration during full polysomnography monitoring and unattended automatic titration with an automatic CPAP device (REMstar Auto) were performed. A separate cohort study of one hundred patients with OSA (AHI = 54.3 ± 18.9 events/h) was also performed by observing the efficacy of CPAP derived from manual titration. The treatment pressure derived from automatic titration (9.8 ± 2.2 cmH(2)O) was significantly higher than that derived from manual titration (7.3 ± 1.5 cmH(2)O; P titration (54.3 ± 18.9 events/h before treatment and 3.3 ± 1.7 events/h after treatment; P titration pressure derived from REMstar Auto is usually higher than the pressure derived from manual titration. © 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology.

  6. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... infant or child manage their lung health, watch parents of children with CF and a respiratory therapist talk about the different techniques they use for airway ... Positive Expiratory Pressure High-Frequency Chest Wall Oscillation (the Vest) Follow ...

  7. EIT based pulsatile impedance monitoring during spontaneous breathing in cystic fibrosis.

    Science.gov (United States)

    Krueger-Ziolek, Sabine; Schullcke, Benjamin; Gong, Bo; Müller-Lisse, Ullrich; Moeller, Knut

    2017-06-01

    both subject groups were speculated to be caused by higher breathing efforts of the CF patients due to airway obstruction leading to higher intrathoracic pressures, and thus to greater changes in lung perfusion.

  8. Study of cyclic and steady particle motion in a realistic human airway model using phase-Doppler anemometry

    Science.gov (United States)

    Jedelský, Jan; Lízal, František; Jícha, Miroslav

    2012-04-01

    Transport and deposition of particles in human airways has been of research interest for many years. Various experimental methods such as constant temperature anemometry, particle image velocimetry and laser-Doppler based techniques were employed for study of aerosol transport in the past. We use Phase-Doppler Particle Analyser (P/DPA) for time resolved size and velocity measurement of liquid aerosol particles in a size range 1 to 8 μm. The di-2ethylhexyl sabacate (DEHS) particles were produced by condensation monodisperse aerosol generator. A thin-wall transparent model of human airways with non-symmetric bifurcations and non-planar geometry containing parts from throat to 3rd-4th generation of bronchi was fabricated for the study. Several cyclic (sinusoidal) breathing regimes were simulated using pneumatic breathing mechanism. Analogous steady-flow regimes were also investigated and used for comparison. An analysis of the particle velocity data was performed with aim to gain deeper understanding of the transport phenomena in the realistic bifurcating airway system. Flows of particles of different sizes in range 1 - 10 μm was found to slightly differ for extremely high Stokes numbers. Differences in steady and cyclic turbulence intensities were documented in the paper. Systematically higher turbulence intensity was found for cyclic flows and mainly in the expiration breathing phase. Negligible differences were found for behaviour of different particle size classes in the inspected range 1 to 8 μm. Possibility of velocity spectra estimation of air flow using the P/DPA data is discussed.

  9. Study of cyclic and steady particle motion in a realistic human airway model using phase-Doppler anemometry

    Directory of Open Access Journals (Sweden)

    Jícha Miroslav

    2012-04-01

    Full Text Available Transport and deposition of particles in human airways has been of research interest for many years. Various experimental methods such as constant temperature anemometry, particle image velocimetry and laser-Doppler based techniques were employed for study of aerosol transport in the past. We use Phase-Doppler Particle Analyser (P/DPA for time resolved size and velocity measurement of liquid aerosol particles in a size range 1 to 8 μm. The di-2ethylhexyl sabacate (DEHS particles were produced by condensation monodisperse aerosol generator. A thin-wall transparent model of human airways with non-symmetric bifurcations and non-planar geometry containing parts from throat to 3rd-4th generation of bronchi was fabricated for the study. Several cyclic (sinusoidal breathing regimes were simulated using pneumatic breathing mechanism. Analogous steady-flow regimes were also investigated and used for comparison. An analysis of the particle velocity data was performed with aim to gain deeper understanding of the transport phenomena in the realistic bifurcating airway system. Flows of particles of different sizes in range 1 – 10 μm was found to slightly differ for extremely high Stokes numbers. Differences in steady and cyclic turbulence intensities were documented in the paper. Systematically higher turbulence intensity was found for cyclic flows and mainly in the expiration breathing phase. Negligible differences were found for behaviour of different particle size classes in the inspected range 1 to 8 μm. Possibility of velocity spectra estimation of air flow using the P/DPA data is discussed.

  10. The patient inflating valve in anaesthesia and resuscitation breathing systems.

    Science.gov (United States)

    Fenton, P M; Bell, G

    2013-03-01

    Patient inflating valves combined with self-inflating bags are known to all anaesthetists as resuscitation devices and are familiar as components of draw-over anaesthesia systems. Their variants are also commonplace in transfer and home ventilators. However, the many variations in structure and function have led to difficulties in their optimal use, definition and classification. After reviewing the relevant literature, we defined a patient inflating valve as a one-way valve that closes an exit port to enable lung inflation, also permitting exhalation and spontaneous breathing, the actions being automatic. We present a new classification based on the mechanism of valve opening/closure; namely elastic recoil of a flexible flap/diaphragm, sliding spindle opened by a spring/magnet or a hollow balloon collapsed by external pressure. The evolution of these valves has been driven by the difficulties documented in critical incidents, which we have used along with information from modern International Organization for Standardization standards to identify 13 ideal properties, the top six of which are non-jamming, automatic, no bypass effect, no rebreathing or air entry at patient end, low resistance, robust and easy to service. The Ambu and the Laerdal valves have remained popular due to their simplicity and reliability. Two new alternatives, the Fenton and Diamedica valves, offer the benefits of location away from the patient while retaining a small functional dead space. They also offer the potential for greater use of hybrid continuous flow/draw-over systems that can operate close to atmospheric pressure. The reliable application of positive end-expiratory pressure/continuous positive airway pressure remains a challenge.

  11. Autogenic drainage for airway clearance in cystic fibrosis.

    Science.gov (United States)

    McCormack, Pamela; Burnham, Paul; Southern, Kevin W

    2017-10-06

    Autogenic drainage is an airway clearance technique that was developed by Jean Chevaillier in 1967. The technique is characterised by breathing control using expiratory airflow to mobilise secretions from smaller to larger airways. Secretions are cleared independently by adjusting the depth and speed of respiration in a sequence of controlled breathing techniques during exhalation. The technique requires training, concentration and effort from the individual. It is important to systematically review the evidence demonstrating that autogenic drainage is an effective intervention for people with cystic fibrosis. To compare the clinical effectiveness of autogenic drainage in people with cystic fibrosis with other physiotherapy airway clearance techniques. We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews, as well as two trials registers (31 August 2017).Dtae of most recent search of the Cochrane Cystic Fibrosis Trials Register: 25 September 2017. We identified randomised and quasi-randomised controlled studies comparing autogenic drainage to another airway clearance technique or no therapy in people with cystic fibrosis for at least two treatment sessions. Data extraction and assessments of risk of bias were independently performed by two authors. The authors assessed the quality of the evidence using the GRADE system. The authors contacted two investigators for further information pertinent to their published studies. Searches retrieved 35 references to 21 individual studies, of which seven (n = 208) were eligible for inclusion. One study was of parallel design with the remaining six being cross-over in design; participant numbers ranged from 17 to 75. The total study duration varied between four days and two years. The age of participants ranged between seven and 63 years with a wide

  12. Effects of Continuous Positive Airway Pressure on Cognitive and Functional Outcome of Stroke Patients with Obstructive Sleep Apnea : A Randomized Controlled Trial

    NARCIS (Netherlands)

    Aaronson, J.A.; Hofman, W.F.; van Bennekom, C.A.M.; van Bezeij, T.; van den Aardweg, J.G.; Groet, E.; Kylstra, W.A.; Schmand, B.

    2016-01-01

    STUDY OBJECTIVES: Obstructive sleep apnea (OSA) in stroke patients is associated with worse functional and cognitive status during inpatient rehabilitation. We hypothesized that a four-week period of continuous positive airway pressure (CPAP) treatment would improve cognitive and functional

  13. In vitro study on work of breathing during non-invasive ventilation using a new variable flow generator.

    Science.gov (United States)

    Flink, Rutger C; van Kaam, Anton H; de Jongh, Frans H

    2015-07-01

    In an attempt to reduce the work of breathing (WOB) and the risk of respiratory failure, preterm infants are increasingly treated with nasal synchronised biphasic positive airway pressure (BPAP) via the Infant Flow SiPAP system. However, the relatively high resistance of the generator limits the pressure amplitude (PA) and pressure build-up (PB) of this system. This in vitro study investigates the impact of a new generator with improved fluid mechanics on the WOB, PA and PB during BPAP. Using a low compliance lung model, WOB, PA and PB, were measured during BPAP using the old and the new Infant Flow generators. Airway resistance (tube sizes 2.5 mm, 3.0 mm and 3.5 mm), nasal interface sizes (small, medium and large) and four different ventilator settings were used to mimic different clinical conditions. Compared with the old generator, the new generator significantly reduced the WOB between 10% and 70%, depending on the measurement configuration. The maximum PA was higher when using the new (6-7 cm H2O) generator versus the old (3-4 cm H2O) generator. During the first 100 ms of inspiration, the new generator reached between 33% and 40% of the peak pressure compared with 11-20% for the old generator. This in vitro study shows that a new generator of the Infant Flow SiPAP device results in a significant reduction in WOB and an increase in PA and PB during BPAP. The results of this study need to be confirmed under variable clinical conditions in preterm infants. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  14. Effects of Continuous Positive Airway Pressure on Cognitive and Functional Outcome of Stroke Patients with Obstructive Sleep Apnea: A Randomized Controlled Trial

    NARCIS (Netherlands)

    Aaronson, Justine A.; Hofman, Winni F.; van Bennekom, Coen A. M.; van Bezeij, Tijs; van den Aardweg, Joost G.; Groet, Erny; Kylstra, Wytske A.; Schmand, Ben

    2016-01-01

    Obstructive sleep apnea (OSA) in stroke patients is associated with worse functional and cognitive status during inpatient rehabilitation. We hypothesized that a four-week period of continuous positive airway pressure (CPAP) treatment would improve cognitive and functional outcomes. We performed a

  15. Positive expiratory pressure - Common clinical applications and physiological effects.

    Science.gov (United States)

    Fagevik Olsén, Monika; Lannefors, Louise; Westerdahl, Elisabeth

    2015-03-01

    Breathing out against resistance, in order to achieve positive expiratory pressure (PEP), is applied by many patient groups. Pursed lips breathing and a variety of devices can be used to create the resistance giving the increased expiratory pressure. Effects on pulmonary outcomes have been discussed in several publications, but the expected underlying physiology of the effect is seldom discussed. The aim of this article is to describe the purpose, performance, clinical application and underlying physiology of PEP when it is used to increase lung volumes, decrease hyperinflation or improve airway clearance. In clinical practice, the instruction how to use an expiratory resistance is of major importance since it varies. Different breathing patterns during PEP increase or reduce expiratory flow, result in movement of EPP centrally or peripherally and can increase or decrease lung volume. It is therefore necessary to give the right instructions to obtain the desired effects. As the different PEP techniques are being used by diverse patient groups it is not possible to give standard instructions. Based on the information given in this article the instructions have to be adjusted to give the optimal effect. There is no consensus regarding optimal treatment frequency and number of cycles included in each treatment session and must also be individualized. In future research, more precise descriptions are needed about physiological aims and specific instructions of how the treatments have been performed to assure as good treatment quality as possible and to be able to evaluate and compare treatment effects. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Effect of a patient engagement tool on positive airway pressure adherence: analysis of a German healthcare provider database.

    Science.gov (United States)

    Woehrle, Holger; Arzt, Michael; Graml, Andrea; Fietze, Ingo; Young, Peter; Teschler, Helmut; Ficker, Joachim H

    2018-01-01

    This study investigated the addition of a real-time feedback patient engagement tool on positive airway pressure (PAP) adherence when added to a proactive telemedicine strategy. Data from a German healthcare provider (ResMed Healthcare Germany) were retrospectively analyzed. Patients who first started PAP therapy between 1 September 2009 and 30 April 2014, and were managed using telemedicine (AirView™; proactive care) or telemedicine + patient engagement tool (AirView™ + myAir™; patient engagement) were eligible. Patient demographics, therapy start date, sleep-disordered breathing indices, device usage hours, and therapy termination rate were obtained and compared between the two groups. The first 500 patients managed by telemedicine-guided care and a patient engagement tool were matched with 500 patients managed by telemedicine-guided care only. The proportion of nights with device usage ≥4 h was 77 ± 25% in the patient engagement group versus 63 ± 32% in the proactive care group (p < 0.001). Therapy termination occurred less often in the patient engagement group (p < 0.001). The apnea-hypopnea index was similar in the two groups, but leak was significantly lower in the patient engagement versus proactive care group (2.7 ± 4.0 vs 4.1 ± 5.3 L/min; p < 0.001). Addition of a patient engagement tool to telemonitoring-guided proactive care was associated with higher device usage and lower leak. This suggests that addition of an engagement tool may help improve PAP therapy adherence and reduce mask leak. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Elective use of the Ventrain for upper airway obstruction during high-frequency jet ventilation.

    Science.gov (United States)

    Fearnley, Robert A; Badiger, Sheela; Oakley, Richard J; Ahmad, Imran

    2016-09-01

    The safety of high pressure source ventilation (jet ventilation) is dependent upon upper airway patency to facilitate adequate passive expiration and prevent increasing intrathoracic pressure and its associated deleterious sequelae. Distortions in airway anatomy may make passive expiration inadequate or impossible in some patients. We report the elective use of the Ventrain device to provide ventilation in a clinical setting of upper airway obstruction in a patient with post radiation fibrosis that had previously prevented passive expiration during attempted high pressure source ventilation. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Oral appliance therapy versus nasal continuous positive airway pressure in obstructive sleep apnea: a randomized, placebo-controlled trial on psychological distress

    NARCIS (Netherlands)

    Aarab, Ghizlane; Nikolopoulou, Maria; Ahlberg, Jari; Heymans, Martijn W.; Hamburger, Hans L.; de Lange, Jan; Lobbezoo, Frank

    2017-01-01

    The aim of this randomized placebo-controlled trail was to compare the effects of an objectively titrated mandibular advancement device (MAD) with those of nasal continuous positive airway pressure (nCPAP) and an intraoral placebo device on symptoms of psychological distress in OSA patients. In a

  19. Sleep architecture, insulin resistance and the nasal cycle: Implications for positive airway pressure therapy

    Directory of Open Access Journals (Sweden)

    Catherine A.P. Crofts

    2018-03-01

    Full Text Available Background: The global pandemic of metabolic disease is worsening. The metabolic theory of obesity proposes that hormonal changes, especially hyperinsulinaemia, precede metabolic disease development. Although quality sleep is recognised as a key factor for good health, less is known about disrupted sleep as a risk factor for hyperinsulinaemia.   Aim: To explore the relationship between sleep, especially sleep architecture and the nasal cycle, on insulin secretion in obstructive sleep apnoea (OSA with comorbid metabolic disease. This review includes a discussion of the potential role of Rest-Activity-Cycler positive airway pressure (RACer-PAP, a novel non-pharmacological OSA treatment strategy.   Methods: A narrative review of all the relevant papers known to the authors was conducted. This review also included results from a polysomnographic sleep clinic pilot study (n = 3 comparing sleep efficiency of RACer-PAP to nasal continuous positive airways pressure (n-CPAP in OSA patients.   Results: Metabolic disease is strongly associated with disturbed sleep. Sleep architecture influences cerebral hormonal secretion, lateral shifts in the autonomic nervous system and nasal airflow dominance. Disturbed sleep shortens short-wave sleep periods, decreasing insulin sensitivity and glucose tolerance. Improvements to metabolic function during n-CPAP treatment are inconsistent. If RACer-PAP demonstrates superior effects on sleep architecture and autonomic function, it may offer advantages in OSA patients with comorbid metabolic disease.   Conclusion: Improving sleep architecture by maintaining the nasal cycle proposes a novel non-pharmacological treatment paradigm for treating OSA with comorbid metabolic disease. Research is required to demonstrate if RACer-PAP therapy influences whole night sleep architecture, sympathovagal balance and markers of metabolic disease.

  20. The impact of dysfunctional breathing on the assessment of asthma control.

    Science.gov (United States)

    Veidal, Sandra; Jeppegaard, Maria; Sverrild, Asger; Backer, Vibeke; Porsbjerg, Celeste

    2017-02-01

    Dysfunctional breathing (DB) is a respiratory disorder, which involves a pattern of breathing too deeply, too superficially and/or too rapidly. In asthma patients, DB may lead to an overestimation of the severity of asthma symptoms, and hence potentially to overtreatment. However, it is not known to which degree DB may affect estimates of asthma control, in a specialist clinical setting. The MAPOut-study examined all patients referred consecutively over a 12-months period for specialist assessment of asthma at the Respiratory Outpatient Clinic at Bispebjerg Hospital in Copenhagen. All patients were examined with the Nijmegen questionnaire with a DB defined as a score ≥23 and the ACQ questionnaire. Linear regression analysis of predictors of ACQ score was performed. Asthma was defined as asthma symptoms and a positive asthma test. Of the 256 patients referred to the lung clinic, data on both the Nijmegen questionnaire and ACQ score was obtained in 127 patients, who were included in the present analysis. Median (range) age: 30 (15-63) years, and 76 (59.8%) were females. DB was found in 31 (24.4%). Asthmatic patients with co-existing DB had a poorer asthma control compared to asthmatics without DB (Median (range) ACQ score: 2.40 (0.20-4.60) vs 1.20 (0.00-4.40); p < 0.001.). A regression analysis showed that the effect of DB on asthma control was independent of airway hyperresponsiveness or airway inflammation in patients with DB. Dysfunctional breathing is common among asthma patients in a specialist setting, and results in a clinically significant underestimation of asthma control, which may potentially lead to overtreatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Role of Aquaporin Water Channels in Airway Fluid Transport, Humidification, and Surface Liquid Hydration

    Science.gov (United States)

    Song, Yuanlin; Jayaraman, Sujatha; Yang, Baoxue; Matthay, Michael A.; Verkman, A.S.

    2001-01-01

    Several aquaporin-type water channels are expressed in mammalian airways and lung: AQP1 in microvascular endothelia, AQP3 in upper airway epithelia, AQP4 in upper and lower airway epithelia, and AQP5 in alveolar epithelia. Novel quantitative methods were developed to compare airway fluid transport–related functions in wild-type mice and knockout mice deficient in these aquaporins. Lower airway humidification, measured from the moisture content of expired air during mechanical ventilation with dry air through a tracheotomy, was 54–56% efficient in wild-type mice, and reduced by only 3–4% in AQP1/AQP5 or AQP3/AQP4 double knockout mice. Upper airway humidification, measured from the moisture gained by dry air passed through the upper airways in mice breathing through a tracheotomy, decreased from 91 to 50% with increasing ventilation from 20 to 220 ml/min, and reduced by 3–5% in AQP3/AQP4 knockout mice. The depth and salt concentration of the airway surface liquid in trachea was measured in vivo using fluorescent probes and confocal and ratio imaging microscopy. Airway surface liquid depth was 45 ± 5 μm and [Na+] was 115 ± 4 mM in wild-type mice, and not significantly different in AQP3/AQP4 knockout mice. Osmotic water permeability in upper airways, measured by an in vivo instillation/sample method, was reduced by ∼40% by AQP3/AQP4 deletion. In doing these measurements, we discovered a novel amiloride-sensitive isosmolar fluid absorption process in upper airways (13% in 5 min) that was not affected by aquaporin deletion. These results establish the fluid transporting properties of mouse airways, and indicate that aquaporins play at most a minor role in airway humidification, ASL hydration, and isosmolar fluid absorption. PMID:11382807

  2. Upper airway resistance syndrome.

    Science.gov (United States)

    Montserrat, J M; Badia, J R

    1999-03-01

    This article reviews the clinical picture, diagnosis and management of the upper airway resistance syndrome (UARS). Presently, there is not enough data on key points like the frequency of UARS and the morbidity associated with this condition. Furthermore, the existence of LIARS as an independent sleep disorder and its relation with snoring and obstructive events is in debate. The diagnosis of UARS is still a controversial issue. The technical limitations of the classic approach to monitor airflow with thermistors and inductance plethysmography, as well as the lack of a precise definition of hypopnea, may have led to a misinterpretation of UARS as an independent diagnosis from the sleep apnea/hypopnea syndrome. The diagnosis of this syndrome can be missed using a conventional polysomnographic setting unless appropriate techniques are applied. The use of an esophageal balloon to monitor inspiratory effort is currently the gold standard. However, other sensitive methods such as the use of a pneumotachograph and, more recently, nasal cannula/pressure transducer systems or on-line monitoring of respiratory impedance with the forced oscillation technique may provide other interesting possibilities. Recognition and characterization of this subgroup of patients within sleep breathing disorders is important because they are symptomatic and may benefit from treatment. Management options to treat UARS comprise all those currently available for sleep apnea/hypopnea syndrome (SAHS). However, the subset of patients classically identified as LIARS that exhibit skeletal craneo-facial abnormalities might possibly obtain further benefit from maxillofacial surgery.

  3. Sleep-induced periodic breathing and apnea: a theoretical study.

    Science.gov (United States)

    Khoo, M C; Gottschalk, A; Pack, A I

    1991-05-01

    To elucidate the mechanisms that lead to sleep-disordered breathing, we have developed a mathematical model that allows for dynamic interactions among the chemical control of respiration, changes in sleep-waking state, and changes in upper airway patency. The increase in steady-state arterial PCO2 accompanying sleep is shown to be inversely related to the ventilatory response to CO2. Chemical control of respiration becomes less stable during the light stage of sleep, despite a reduction in chemoresponsiveness, due to a concomitant increase in "plant gain" (i.e., responsiveness of blood gases to ventilatory changes). The withdrawal of the "wakefulness drive" during sleep onset represents a strong perturbation to respiratory control: higher magnitudes and rates of withdrawal of this drive favor instability. These results may account for the higher incidence of periodic breathing observed during light sleep and sleep onset. Periodic ventilation can also result from repetitive alternations between sleep onset and arousal. The potential for instability is further compounded if the possibility of upper airway occlusion is also included. In systems with high controller gains, instability is mediated primarily through chemoreflex overcompensation. However, in systems with depressed chemoresponsiveness, rapid sleep onset and large blood gas fluctuations trigger repetitive episodes of arousal and hyperpnea alternating with apneas that may or may not be obstructive. Between these extremes, more complex patterns can arise from the interaction between chemoreflex-mediated oscillations of shorter-cycle-duration (approximately 36 s) and longer-wavelength (approximately 60-80 s) state-driven oscillations.

  4. Cardiorespiratory and autonomic interactions during snoring related resistive breathing.

    Science.gov (United States)

    Mateika, J H; Mitru, G

    2001-03-15

    We hypothesized that blood pressure (BP) is less during snoring as compared to periods of non-snoring in non-apneic individuals. Furthermore, we hypothesized that this reduction may be accompanied by a simultaneous decrease in sympathetic (SNSA) and parasympathetic (PNSA) nervous system activity and an increase in heart rate (HR). N/A. N/A. N/A. The variables mentioned above in addition to breathing frequency were measured in 9 subjects during NREM sleep. In addition, the lowest systolic (SBP) and diastolic blood pressure (DBP) during inspiration and the highest SBP and DBP during expiration was determined breath-by-breath from segments selected from each NREM cycle. Heart rate variability was used as a marker of autonomic nervous system activity. Our results showed that BP during snoring decreased compared to non-snoring and the breath-by-breath BP analysis suggested that this difference may have been mediated by changes in intrathoracic pressure. In conjunction with the decrease in BP, SNSA decreased and HR increased however PNSA remained constant. Thus, a decrease in PNSA was likely not the primary mechanism responsible for the HR response. We conclude that BP responses and SNSA during snoring are similar to that reported previously in non-snoring individuals. However, the causal mechanisms maybe different and manifested in other measures such as HR. Thus, nocturnal cardiovascular and autonomic function maybe uniquely different in non-apneic snoring individuals.

  5. Comparison of three continuous positive airway pressure (CPAP) interfaces in healthy Beagle dogs during medetomidine-propofol constant rate infusions.

    Science.gov (United States)

    Meira, Carolina; Joerger, Fabiola B; Kutter, Annette P N; Waldmann, Andreas; Ringer, Simone K; Böehm, Stephan H; Iff, Samuel; Mosing, Martina

    2018-03-01

    To compare the efficacy of three continuous positive airway pressure (CPAP) interfaces in dogs on gas exchange, lung volumes, amount of leak during CPAP and rebreathing in case of equipment failure or disconnection. Randomized, prospective, crossover, experimental trial. Ten purpose-bred Beagle dogs. Dogs were in dorsal recumbency during medetomidine-propofol constant rate infusions, breathing room air. Three interfaces were tested in each dog in a consecutive random order: custom-made mask (M), conical face mask (FM) and helmet (H). End-expiratory lung impedance (EELI) measured by electrical impedance tomography was assessed with no interface (baseline), with the interface only (No-CPAP for 3 minutes) and at 15 minutes of 7 cmH 2 O CPAP (CPAP-delivery). PaO 2 was assessed at No-CPAP and CPAP-delivery, partial pressure of inspired carbon dioxide (PICO 2 ; rebreathing assessment) at No-CPAP and the interface leak (ΔP leak ) at CPAP-delivery. Mixed-effects linear regression models were used for statistical analysis (pCPAP-delivery, all interfaces increased EELI by 7% (pCPAP, less rebreathing occurred with M (0.5 kPa, 4 mmHg) than with FM (1.8 kPa, 14 mmHg) and with H (1.4 kPa, 11 mmHg), but also lower PaO 2 was measured with M (9.3 kPa, 70 mmHg) than with H (11.9 kPa, 90 mmHg) and FM (10.8 kPa, 81 mmHg). All three interfaces can be used to provide adequate CPAP in dogs. The leak during CPAP-delivery and the risk of rebreathing and hypoxaemia, when CPAP is not maintained, can be significant. Therefore, animals should always be supervised during administration of CPAP with any of the three interfaces. The performance of the custom-made M was not superior to the other interfaces. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

  6. Rule-based detection of intrathoracic airway trees

    International Nuclear Information System (INIS)

    Sonka, M.; Park, W.; Hoffman, E.A.

    1996-01-01

    New sensitive and reliable methods for assessing alterations in regional lung structure and function are critically important for the investigation and treatment of pulmonary diseases. Accurate identification of the airway tree will provide an assessment of airway structure and will provide a means by which multiple volumetric images of the lung at the same lung volume over time can be used to assess regional parenchymal changes. The authors describe a novel rule-based method for the segmentation of airway trees from three-dimensional (3-D) sets of computed tomography (CT) images, and its validation. The presented method takes advantage of a priori anatomical knowledge about pulmonary airway and vascular trees and their interrelationships. The method is based on a combination of 3-D seeded region growing that is used to identify large airways, rule-based two-dimensional (2-D) segmentation of individual CT slices to identify probable locations of smaller diameter airways, and merging of airway regions across the 3-D set of slices resulting in a tree-like airway structure. The method was validated in 40 3-mm-thick CT sections from five data sets of canine lungs scanned via electron beam CT in vivo with lung volume held at a constant pressure. The method's performance was compared with that of the conventional 3-D region growing method. The method substantially outperformed an existing conventional approach to airway tree detection

  7. Comparison of pulsed versus continuous oxygen delivery using realistic adult nasal airway replicas

    Directory of Open Access Journals (Sweden)

    Chen JZ

    2017-08-01

    Full Text Available John Z Chen,1 Ira M Katz,2 Marine Pichelin,2 Kaixian Zhu,3 Georges Caillibotte,2 Michelle L Noga,4 Warren H Finlay,1 Andrew R Martin1 1Department of Mechanical Engineering, University of Alberta, Edmonton, AB, Canada; 2Medical R&D, Air Liquide Santé International, Centre de Recherche Paris-Saclay, Les Loges-en-Josas, 3Centre Explor!, Air Liquide Healthcare, Gentilly, France; 4Radiology and Diagnostic Imaging, University of Alberta, Edmonton, AB, Canada Background: Portable oxygen concentrators (POCs typically include pulse flow (PF modes to conserve oxygen. The primary aims of this study were to develop a predictive in vitro model for inhaled oxygen delivery using a set of realistic airway replicas, and to compare PF for a commercial POC with steady flow (SF from a compressed oxygen cylinder. Methods: Experiments were carried out using a stationary compressed oxygen cylinder, a POC, and 15 adult nasal airway replicas based on airway geometries derived from medical images. Oxygen delivery via nasal cannula was tested at PF settings of 2.0 and 6.0, and SF rates of 2.0 and 6.0 L/min. A test lung simulated three breathing patterns representative of a chronic obstructive pulmonary disease patient at rest, during exercise, and while asleep. Volume-averaged fraction of inhaled oxygen (FiO2 was calculated by analyzing oxygen concentrations sampled at the exit of each replica and inhalation flow rates over time. POC pulse volumes were also measured using a commercial O2 conserver test system to attempt to predict FiO2 for PF. Results: Relative volume-averaged FiO2 using PF ranged from 68% to 94% of SF values, increasing with breathing frequency and tidal volume. Three of 15 replicas failed to trigger the POC when used with the sleep breathing pattern at the 2.0 setting, and four of 15 replicas failed to trigger at the 6.0 setting. FiO2 values estimated from POC pulse characteristics followed similar trends but were lower than those derived from

  8. Phosphotyrosine phosphatase and tyrosine kinase inhibition modulate airway pressure-induced lung injury.

    Science.gov (United States)

    Parker, J C; Ivey, C L; Tucker, A

    1998-11-01

    We determined whether drugs which modulate the state of protein tyrosine phosphorylation could alter the threshold for high airway pressure-induced microvascular injury in isolated perfused rat lungs. Lungs were ventilated for successive 30-min periods with peak inflation pressures (PIP) of 7, 20, 30, and 35 cmH2O followed by measurement of the capillary filtration coefficient (Kfc), a sensitive index of hydraulic conductance. In untreated control lungs, Kfc increased by 1.3- and 3.3-fold relative to baseline (7 cmH2O PIP) after ventilation with 30 and 35 cmH2O PIP. However, in lungs treated with 100 microM phenylarsine oxide (a phosphotyrosine phosphatase inhibitor), Kfc increased by 4.7- and 16.4-fold relative to baseline at these PIP values. In lungs treated with 50 microM genistein (a tyrosine kinase inhibitor), Kfc increased significantly only at 35 cmH2O PIP, and the three groups were significantly different from each other. Thus phosphotyrosine phosphatase inhibition increased the susceptibility of rat lungs to high-PIP injury, and tyrosine kinase inhibition attenuated the injury relative to the high-PIP control lungs.

  9. Boussignac continuous positive airway pressure for the management of acute cardiogenic pulmonary edema: prospective study with a retrospective control group

    Directory of Open Access Journals (Sweden)

    Aarts Leon PHJ

    2007-12-01

    Full Text Available Abstract Background Continuous positive airway pressure (CPAP treatment for acute cardiogenic pulmonary edema can have important benefits in acute cardiac care. However, coronary care units are usually not equipped and their personnel not adequately trained for applying CPAP with mechanical ventilators. Therefore we investigated in the coronary care unit setting the feasibility and outcome of the simple Boussignac mask-CPAP (BCPAP system that does not need a mechanical ventilator. Methods BCPAP was introduced in a coronary care unit where staff had no CPAP experience. All consecutive patients transported to our hospital with acute cardiogenic pulmonary edema, a respiratory rate > 25 breaths/min and a peripheral arterial oxygen saturation of Results During the 2-year prospective BCPAP study period 108 patients were admitted with acute cardiogenic pulmonary edema. Eighty-four of these patients (78% were treated at the coronary care unit of which 66 (61% were treated with BCPAP. During the control period 66 patients were admitted over a 1-year period of whom 31 (47% needed respiratory support in the intensive care unit. BCPAP treatment was associated with a reduced hospital length of stay and fewer transfers to the intensive care unit for intubation and mechanical ventilation. Overall estimated savings of approximately € 3,800 per patient were achieved with the BCPAP strategy compared to conventional treatment. Conclusion At the coronary care unit, BCPAP was feasible, medically effective, and cost-effective in the treatment of acute cardiogenic pulmonary edema. Endpoints included mortality, coronary care unit and hospital length of stay, need of ventilatory support, and cost (savings.

  10. Airway hyperresponsiveness; smooth muscle as the principal actor [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Anne-Marie Lauzon

    2016-03-01

    Full Text Available Airway hyperresponsiveness (AHR is a defining characteristic of asthma that refers to the capacity of the airways to undergo exaggerated narrowing in response to stimuli that do not result in comparable degrees of airway narrowing in healthy subjects. Airway smooth muscle (ASM contraction mediates airway narrowing, but it remains uncertain as to whether the smooth muscle is intrinsically altered in asthmatic subjects or is responding abnormally as a result of the milieu in which it sits. ASM in the trachea or major bronchi does not differ in its contractile characteristics in asthmatics, but the more pertinent peripheral airways await complete exploration. The mass of ASM is increased in many but not all asthmatics and therefore cannot be a unifying hypothesis for AHR, although when increased in mass it may contribute to AHR. The inability of a deep breath to reverse or prevent bronchial narrowing in asthma may reflect an intrinsic difference in the mechanisms that lead to softening of contracted ASM when subjected to stretch. Cytokines such as interleukin-13 and tumor necrosis factor-α promote a more contractile ASM phenotype. The composition and increased stiffness of the matrix in which ASM is embedded promotes a more proliferative and pro-inflammatory ASM phenotype, but the expected dedifferentiation and loss of contractility have not been shown. Airway epithelium may drive ASM proliferation and/or molecular remodeling in ways that may lead to AHR. In conclusion, AHR is likely multifactorial in origin, reflecting the plasticity of ASM properties in the inflammatory environment of the asthmatic airway.

  11. Compressed air demand-type firefighter's breathing system, volume 1. [design analysis and performance tests

    Science.gov (United States)

    Sullivan, J. L.

    1975-01-01

    The commercial availability of lightweight high pressure compressed air vessels has resulted in a lightweight firefighter's breathing apparatus. The improved apparatus, and details of its design and development are described. The apparatus includes a compact harness assembly, a backplate mounted pressure reducer assembly, a lightweight bubble-type facemask with a mask mounted demand breathing regulator. Incorporated in the breathing regulator is exhalation valve, a purge valve and a whistle-type low pressure warning that sounds only during inhalation. The pressure reducer assembly includes two pressure reducers, an automatic transfer valve and a signaling device for the low pressure warning. Twenty systems were fabricated, tested, refined through an alternating development and test sequence, and extensively examined in a field evaluation program. Photographs of the apparatus are included.

  12. Effects of slow breathing rate on heart rate variability and arterial baroreflex sensitivity in essential hypertension.

    Science.gov (United States)

    Li, Changjun; Chang, Qinghua; Zhang, Jia; Chai, Wenshu

    2018-05-01

    This study is to investigate the effects of slow breathing on heart rate variability (HRV) and arterial baroreflex sensitivity in essential hypertension.We studied 60 patients with essential hypertension and 60 healthy controls. All subjects underwent controlled breathing at 8 and 16 breaths per minute. Electrocardiogram, respiratory, and blood pressure signals were recorded simultaneously. We studied effects of slow breathing on heart rate, blood pressure and respiratory peak, high-frequency (HF) power, low-frequency (LF) power, and LF/HF ratio of HRV with traditional and corrected spectral analysis. Besides, we tested whether slow breathing was capable of modifying baroreflex sensitivity in hypertensive subjects.Slow breathing, compared with 16 breaths per minute, decreased the heart rate and blood pressure (all P hypertensive subjects. Slow breathing increased baroreflex sensitivity in hypertensive subjects (from 59.48 ± 6.39 to 78.93 ± 5.04 ms/mm Hg, P hypertension. Besides, slow breathing increased baroreflex sensitivity in hypertensive subjects. These demonstrate slow breathing is indeed capable of shifting sympatho-vagal balance toward vagal activities and increasing baroreflex sensitivity, suggesting a safe, therapeutic approach for essential hypertension.

  13. Airway Management of the Patient with Maxillofacial Trauma: Review of the Literature and Suggested Clinical Approach

    Directory of Open Access Journals (Sweden)

    Michal Barak

    2015-01-01

    Full Text Available According to the Advanced Trauma Life Support recommendations for managing patients with life-threatening injuries, securing the airway is the first task of a primary caregiver. Airway management of patients with maxillofacial trauma is complex and crucial because it can dictate a patient’s survival. Securing the airway of patients with maxillofacial trauma is often extremely difficult because the trauma involves the patient’s airway and their breathing is compromised. In these patients, mask ventilation and endotracheal intubation are anticipated to be difficult. Additionally, some of these patients may not yet have been cleared of a cervical spine injury, and all are regarded as having a full stomach and having an increased risk of regurgitation and pulmonary aspiration. The requirements of the intended maxillofacial operation may often preclude the use of an oral intubation tube, and alternative methods for securing the airway should be considered before the start of the surgery. In order to improve the clinical outcome of patients with maxillofacial trauma, cooperation between maxillofacial surgeons, anesthesiologists, and trauma specialists is needed. In this review, we discuss the complexity and difficulties of securing the airway of patients with maxillofacial trauma and present our approach for airway management of such patients.

  14. Bilateral diaphragmatic paralysis after cardiac surgery: ventilatory assistance by nasal mask continuous positive airway pressure.

    Science.gov (United States)

    Hoch, B; Zschocke, A; Barth, H; Leonhardt, A

    2001-01-01

    The case of an 8-month-old boy with bilateral diaphragmatic paralysis after surgical reoperation for congenital heart disease is presented. In order to avoid repeated intubation and long-term mechanical ventilation or tracheotomy, we used nasal mask continuous positive airway pressure (CPAP) as an alternative method for assisted ventilation. Within 24 hours the boy accepted the nasal mask and symptoms such as dyspnea and sweating disappeared. Respiratory movements became regular and oxygen saturation increased. Nasal mask CPAP may serve as an alternative treatment of bilateral diaphragmatic paralysis in infants, thereby avoiding tracheotomy or long-term mechanical ventilation.

  15. Practice parameters for the surgical modifications of the upper airway for obstructive sleep apnea in adults.

    Science.gov (United States)

    Aurora, R Nisha; Casey, Kenneth R; Kristo, David; Auerbach, Sanford; Bista, Sabin R; Chowdhuri, Susmita; Karippot, Anoop; Lamm, Carin; Ramar, Kannan; Zak, Rochelle; Morgenthaler, Timothy I

    2010-10-01

    appliances, which are more often appropriate in mild and moderate OSA patients, have been considered and found ineffective or undesirable (Option). UPPP as a sole procedure, with or without tonsillectomy, does not reliably normalize the AHI when treating moderate to severe obstructive sleep apnea syndrome. Therefore, patients with severe OSA should initially be offered positive airway pressure therapy, while those with moderate OSA should initially be offered either PAP therapy or oral appliances (Option). Use of multi-level or stepwise surgery (MLS), as a combined procedure or as stepwise multiple operations, is acceptable in patients with narrowing of multiple sites in the upper airway, particularly if they have failed UPPP as a sole treatment (Option). LAUP is not routinely recommended as a treatment for obstructive sleep apnea syndrome (Standard). RFA can be considered as a treatment in patients with mild to moderate obstructive sleep apnea who cannot tolerate or who are unwilling to adhere to positive airway pressure therapy, or in whom oral appliances have been considered and found ineffective or undesirable (Option). Palatal implants may be effective in some patients with mild obstructive sleep apnea who cannot tolerate or who are unwilling to adhere to positive airway pressure therapy, or in whom oral appliances have been considered and found ineffective or undesirable (Option). Postoperatively, after an appropriate period of healing, patients should undergo follow-up evaluation including an objective measure of the presence and severity of sleep-disordered breathing and oxygen saturation, as well as clinical assessment for residual symptoms. Additionally, patients should be followed over time to detect the recurrence of disease (Standard). While there has been significant progress made in surgical techniques for the treatment of OSA, there is a lack of rigorous data evaluating surgical modifications of the upper airway. Systematic and methodical investigations are

  16. Slow loaded breathing training improves blood pressure, lung capacity and arm exercise endurance for older people with treated and stable isolated systolic hypertension.

    Science.gov (United States)

    Ublosakka-Jones, Chulee; Tongdee, Phailin; Pachirat, Orathai; Jones, David A

    2018-03-28

    Hypertension and reduced lung function are important features of aging. Slow loaded breathing training reduces resting blood pressure and the question is whether this can also improve lung function. Thirty-two people (67 ± 5 years, 16 male) with controlled isolated systolic hypertension undertook an eight weeks randomised controlled training trial with an inspiratory load of 25% maximum inspiratory pressure (MIP) at 6 breaths per minute (slow loaded breathing; SLB) or deep breathing control (CON). Outcome measures were resting blood pressure (BP) and heart rate; MIP; lung capacity; chest and abdominal expansion; arm cranking exercise endurance at 50% heart rate reserve. Home based measurement of resting systolic BP decreased by 20 mm Hg (15 to 25) (Mean and 95%CI) for SLB and by 5 mm Hg (1 to 7) for CON. Heart rate and diastolic BP also decreased significantly for SLB but not CON. MIP increased by 15.8 cm H 2 O (11.8 to 19.8) and slow vital capacity by 0.21 L (0.15 to 0.27) for SLB but not for CON. Chest and abdominal expansion increased by 2.3 cm (2.05 to 2.55) and 2.5 cm (2.15 to 2.85), respectively for SLB and by 0.5 cm (0.26 to 0.74) and 1.7 cm (1.32 to 2.08) for CON. Arm exercise time increased by 4.9 min (3.65 to 5.15) for SLB with no significant change for CON. Slow inspiratory muscle training is not only effective in reducing resting BP, even in older people with well controlled isolated systolic hypertension but also increases inspiratory muscle strength, lung capacity and arm exercise duration. Copyright © 2018. Published by Elsevier Inc.

  17. Sexual function and obstructive sleep apnea-hypopnea : A randomized clinical trial evaluating the effects of oral-appliance and continuous positive airway pressure therapy

    NARCIS (Netherlands)

    Hoekema, Aarnoud; Stel, Anna-Lucia; Stegenga, Boudewijn; van der Hoeven, Johannes H.; Wijkstra, Peter J.; van Driel, Mels F.; de Bont, Lambert G. M.

    Introduction. The obstructive sleep apnea-hypopnea syndrome (OSAHS) is associated with sexual dysfunction. Although successful treatment with continuous positive airway pressure (CPAP) has been demonstrated to improve sexual function, the effects of oral-appliance therapy are unknown. Aim. The aims

  18. Dioscorin pre-treatment protects A549 human airway epithelial cells from hydrogen peroxide-induced oxidative stress.

    Science.gov (United States)

    Hsu, Jeng-Yuan; Chu, Jao-Jia; Chou, Ming-Chih; Chen, Ya-Wen

    2013-10-01

    Hydrogen peroxide (H(2)O(2)) is a highly reactive oxygen species involved in lung and bronchial epithelium injury. Increased H(2)O(2) levels have been reported in expired breath condensates of patients with inflammatory airway diseases such as chronic obstructive pulmonary disease. Protecting airway epithelial cells from oxidative stress is an important task in the prevention and management of airway diseases. Previous studies demonstrate that yam (Dioscorea batatas Decne) has antioxidant and anti-trypsin activities. This study evaluated the validity of dioscorin in vitro. The results showed that dioscorin attenuated the alteration of H(2)O(2) on G2/M cell cycle arrest. This might be associated with the activation of IκB and subsequent inactivation of NF-κB. Furthermore, dioscorin suppressed IL-8 secretion and reduced changes of adhesion molecule expressions in H(2)O(2)-injured A549 cells. These results help in understanding the potential of traditional Chinese herbal medicine as treatment for airway inflammatory diseases.

  19. Dynamic airway pressure-time curve profile (Stress Index): a systematic review.

    Science.gov (United States)

    Terragni, Pierpaolo; Bussone, Guido; Mascia, Luciana

    2016-01-01

    The assessment of respiratory mechanics at the bedside is necessary in order to identify the most protective ventilatory strategy. Indeed in the last 20 years, adverse effects of positive ventilation to the lung structures have led to a reappraisal of the objectives of mechanical ventilation. The ventilator setting requires repeated readjustment over the period of mechanical ventilation dependency and careful respiratory monitoring to minimize the risks, preventing further injury and permitting the lung and airways healing. Among the different methods that have been proposed and validated, the analysis of dynamic P-t curve (named Stress Index, SI) represents an adequate tool available at the bedside, repeatable and, therefore, able to identify the amount of overdistension occurring in the daily clinical practice, when modifying positive end-expiratory pressure. In this review we will analyze the evidence that supports respiratory mechanics assessment at the bedside and the application of the dynamic P/t curve profile (SI) to optimize protective ventilation in patients with acute respiratory failure.

  20. A Randomized Trial of Low-Flow Oxygen versus Nasal Continuous Positive Airway Pressure in Preterm Infants

    DEFF Research Database (Denmark)

    Heiring, Christian; Steensberg, Jesper; Bjerager, Mia

    2015-01-01

    BACKGROUND: Nasal continuous positive airway pressure (nCPAP) stabilizes the residual volume and may decrease the risk of 'atelectotrauma', potentially promoting lung development in neonates. OBJECTIVES: To assess whether replacing nCPAP by low-flow O2 by nasal cannula affects lung function...... the a/A pO2 ratio or weight gain negatively. Thus, prolonged nCPAP seems not to have a positive effect on lung function at 28 days of life and replacement by low-flow O2 could reduce the cost of equipment and increase the ease of nursing....

  1. Negative-Pressure Pulmonary Edema.

    Science.gov (United States)

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

    2016-10-01

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

  2. Use of extraglottic airways in patients undergoing ambulatory laparoscopic surgery without the need for tracheal intubation

    Directory of Open Access Journals (Sweden)

    T Suhitharan

    2013-01-01

    Full Text Available Background: Second generation extraglottic airway devices with gastric access and separate breathing channels have ushered in a new era where their use is increasingly prevalent in surgical patients who would have been traditionally intubated for general anesthesia. New innovations like the i-gel, which is constructed of a thermoplastic elastomer, provide an airtight seal around patient′s perilaryngeal anatomy without the inflatable cuff mechanism found in the laryngeal mask airway supreme (LMAS. Methods: We conducted a randomized controlled trial comparing the LMAS with the i-gel in 70 anesthetized paralyzed patients undergoing laparoscopic female sterilization. Our primary outcome measure was the oropharyngeal leak pressure (OLP. We studied secondary outcomes of successful first attempt insertion rates, time and ease of the airway and gastric tube insertion, leak fractions and pharyngeal morbidity. Results: We found no difference in the OLP between LMAS and i-gel, 25.9 (4.2 versus 24.4 (4.3 s, P=0.153. Both devices had similar first attempt insertion rates (LMAS 94% vs. i-gel 91% with similar ease and comparable times to achieve an effective airway, LMAS 14.7 (2.7 versus i-gel 16.5 (9.6 s, P=0.306, although gastric tube insertion was easier and faster for the LMAS, 7.9 (1.9 versus i-gel 14.8 (7.7 s, P<0.005. Intraoperatively, there was a significantly greater leak fraction with the i-gel of 0.06 (0.03 versus 0.04 (0.02 with the LMAS, P=0.013. Three patients (8.6% with LMAS had mild sore throat; one patient (2.9% had mucosal injury. No complications were documented in the i-gel group. Conclusions: Both these extraglottic airway devices offer similar OLPs, high insertion success rates at the first attempt with similar ease and insertion times (albeit longer gastric tube insertion with i-gel. Both provided effective ventilation despite a higher leak fraction with i-gel that was clinically inconsequential.

  3. The Role of Continuous Positive Airway Pressure Therapy in the Management of Respiratory Distress in Extremely Premature Infants

    OpenAIRE

    Sekar, Kris

    2006-01-01

    The use of mechanical ventilation for the treatment of respiratory distress syndrome (RDS) in low birth weight infants may cause barotrauma, volutrauma, and chronic lung disease. Different continuous positive airway pressure (CPAP) delivery systems exist, each with its own practical and clinical advantages and disadvantages. CPAP can be used as either a primary or an adjunctive respiratory support for RDS. Research demonstrates that CPAP decreases the incidence of respiratory failure after ex...

  4. Multiple-Breath Washout Outcomes Are Sensitive to Inflammation and Infection in Children with Cystic Fibrosis.

    Science.gov (United States)

    Ramsey, Kathryn A; Foong, Rachel E; Grdosic, Jasmine; Harper, Alana; Skoric, Billy; Clem, Charles; Davis, Miriam; Turkovic, Lidija; Stick, Stephen M; Davis, Stephanie D; Ranganathan, Sarath C; Hall, Graham L

    2017-09-01

    The lung clearance index is a measure of ventilation distribution derived from the multiple-breath washout technique. The lung clearance index is increased in the presence of lower respiratory tract inflammation and infection in infants with cystic fibrosis; however, the associations during the preschool years are unknown. We assessed the ability of the lung clearance index to detect the presence and extent of lower respiratory tract inflammation and infection in preschool children with cystic fibrosis. Ventilation distribution outcomes were assessed at 82 visits with 58 children with cystic fibrosis and at 38 visits with 31 healthy children aged 3-6 years. Children with cystic fibrosis also underwent bronchoalveolar lavage fluid collection for detection of lower respiratory tract inflammation and infection. Associations between multiple-breath washout indices and the presence and extent of airway inflammation and infection were assessed using linear mixed effects models. Lung clearance index was elevated in children with cystic fibrosis (mean [SD], 8.00 [1.45]) compared with healthy control subjects (6.67 [0.56]). In cystic fibrosis, the lung clearance index was elevated in individuals with lower respiratory tract infections (difference compared with uninfected [95% confidence interval], 0.62 [0.06, 1.18]) and correlated with the extent of airway inflammation. These data suggest that the lung clearance index may be a useful surveillance tool for monitoring the presence and extent of lower airway inflammation and infection in preschool children with cystic fibrosis.

  5. Effect of device-guided breathing exercises on blood pressure in hypertensive patients with type 2 diabetes mellitus : A randomized controlled trial

    NARCIS (Netherlands)

    Logtenberg, Susan J.; Kleefstra, Nanne; Houweling, Sebastlaan T.; Groenier, Klaas H.; Bilo, Henk J.

    Objective In patients with type 2 diabetes mellitus (DM2), it is hard to reach treatment objectives for blood pressure (BP) with classical treatment options. Recently, reducing breathing frequency has been advocated as a method to reduce BP. We examined if an electronic device such as Resperate, by

  6. Differential effects of airway anesthesia on ozone-induced pulmonary responses in human subjects.

    Science.gov (United States)

    Schelegle, E S; Eldridge, M W; Cross, C E; Walby, W F; Adams, W C

    2001-04-01

    We examined the effect of tetracaine aerosol inhalation, a local anesthetic, on lung volume decrements, rapid shallow breathing, and subjective symptoms of breathing discomfort induced by the acute inhalation of 0.30 ppm ozone for 65 min in 22 ozone-sensitive healthy human subjects. After 50 min of ozone inhalation FEV(1) was reduced 24%, breathing frequency was increased 40%, tidal volume was decreased 31%, and total subjective symptom score was increased (71.2, compared with 3.8 for filtered air exposure). Inhalation of tetracaine aerosol resulted in marked reductions in ozone-induced subjective symptoms of throat tickle and/or irritation (92.1%), cough (78.5%), shortness of breath (72.5%), and pain on deep inspiration (69.4%). In contrast, inhalation of tetracaine aerosol (mass median aerodynamic diameter of 3.52 microm with a geometric standard deviation of 1.92) resulted in only minor and inconsistent rectification of FEV(1) decrements (5.0%) and breathing frequency (-3.8%) that was not significantly different from that produced by saline aerosol alone (FEV(1), 5.1% and breathing frequency, -2.7%). Our data are consistent with afferent endings located within the large conducting airways of the tracheobronchial tree being primarily responsible for ozone-induced subjective symptoms and provides strong evidence that ozone-induced inhibition of maximal inspiratory effort is not dependent on conscious sensations of inspiratory discomfort.

  7. Craniofacial changes and symptoms of sleep-disordered breathing in healthy children

    Directory of Open Access Journals (Sweden)

    Maria Christina Thomé Pacheco

    2015-06-01

    Full Text Available INTRODUCTION: The main cause of mouth breathing and sleep-disordered breathing (SDB in childhood is associated with upper airway narrowing to varying degrees. OBJECTIVE: The aim of this study was to assess the prevalence of morphological and functional craniofacial changes and the main clinical symptoms of SDB in healthy children. METHODS: A cross-sectional observational study was conducted. A sample comprising 687 healthy schoolchildren, aged 7-12 years old and attending public schools, was assessed by medical history, clinical medical and dental examination, and respiratory tests. The self-perceived quality of life of mouth breathing children was obtained by a validated questionnaire. RESULTS: Out of the total sample, 520 children were nose breathers (NB while 167 (24.3% were mouth breathers (MB; 32.5% had severe hypertrophy of the palatine tonsils, 18% had a Mallampati score of III or IV, 26.1% had excessive overjet and 17.7% had anterior open bite malocclusion. Among the MB, 53.9% had atresic palate, 35.9% had lip incompetence, 33.5% reported sleepiness during the day, 32.2% often sneezed, 32.2% had a stuffy nose, 19.6% snored, and 9.4% reported having the feeling to stop breathing while asleep. However, the self-perception of their quality of life was considered good. CONCLUSION: High prevalence of facial changes as well as signs and symptoms of mouth breathing were found among health children, requiring early diagnosis and treatment to reduce the risk of SDB.

  8. The effect of obstructive sleep apnea and treatment with continuous positive airway pressure on stroke rehabilitation: rationale, design and methods of the TOROS study

    NARCIS (Netherlands)

    Aaronson, J.A.; van Bennekom, C.A.M.; Hofman, W.F.; van Bezeij, T.; van den Aardweg, J.G.; Groet, E.; Kylstra, W.A.; Schmand, B.A.

    2014-01-01

    BACKGROUND: Obstructive sleep apnea is a common sleep disorder in stroke patients. Obstructive sleep apnea is associated with stroke severity and poor functional outcome. Continuous positive airway pressure seems to improve functional recovery in stroke rehabilitation. To date, the effect of

  9. Design and Validation of a Breathing Detection System for Scuba Divers

    Directory of Open Access Journals (Sweden)

    Corentin Altepe

    2017-06-01

    Full Text Available Drowning is the major cause of death in self-contained underwater breathing apparatus (SCUBA diving. This study proposes an embedded system with a live and light-weight algorithm which detects the breathing of divers through the analysis of the intermediate pressure (IP signal of the SCUBA regulator. A system composed mainly of two pressure sensors and a low-power microcontroller was designed and programmed to record the pressure sensors signals and provide alarms in absence of breathing. An algorithm was developed to analyze the signals and identify inhalation events of the diver. A waterproof case was built to accommodate the system and was tested up to a depth of 25 m in a pressure chamber. To validate the system in the real environment, a series of dives with two different types of workload requiring different ranges of breathing frequencies were planned. Eight professional SCUBA divers volunteered to dive with the system to collect their IP data in order to participate to validation trials. The subjects underwent two dives, each of 52 min on average and a maximum depth of 7 m. The algorithm was optimized for the collected dataset and proved a sensitivity of inhalation detection of 97.5% and a total number of 275 false positives (FP over a total recording time of 13.9 h. The detection algorithm presents a maximum delay of 5.2 s and requires only 800 bytes of random-access memory (RAM. The results were compared against the analysis of video records of the dives by two blinded observers and proved a sensitivity of 97.6% on the data set. The design includes a buzzer to provide audible alarms to accompanying dive buddies which will be triggered in case of degraded health conditions such as near drowning (absence of breathing, hyperventilation (breathing frequency too high and skip-breathing (breathing frequency too low measured by the improper breathing frequency. The system also measures the IP at rest before the dive and indicates with

  10. Pediatric cardiac catheterization procedure with dexmedetomidine sedation: Radiographic airway patency assessment

    Directory of Open Access Journals (Sweden)

    Ashwini Thimmarayappa

    2015-01-01

    Full Text Available Aims: The aim of the study was to measure airway patency objectively during dexmedetomidine sedation under radiographic guidance in spontaneously breathing pediatric patients scheduled for cardiac catheterization procedures. Subjects and Methods: Thirty-five patients in the age group 5-10 years scheduled for cardiac catheterization procedures were enrolled. All study patients were given loading dose of dexmedetomidine at 1 mg/kg/min for 10 min and then maintenance dose of 1.5 mg/kg/h. Radiographic airway patency was assessed at the start of infusion (0 min and after 30 min. Antero-posterior (AP diameters were measured manually at the nasopharyngeal and retroglossal levels. Dynamic change in airway between inspiration and expiration was considered a measure of airway collapsibility. Patients were monitored for hemodynamics, recovery time and complications. Statistical Analysis: Student paired t-test was used for data analysis. P < 0.05 was considered significant. Results: Minimum and maximum AP diameters were compared at 0 and 30 min. Nasopharyngeal level showed significant reduction in the minimum (6.27 ± 1.09 vs. 4.26 ± 1.03, P < 0.0001 and maximum (6.51 ± 1.14 vs. 5.99 ± 1.03, P < 0.0001 diameters. Similarly retroglossal level showed significant reduction in the minimum (6.98 ± 1.09 vs. 5.27 ± 1.15, P < 0.0001 and maximum (7.49 ± 1.22 vs. 6.92 ± 1.12, P < 0.0003 diameters. The degree of collapsibility was greater at 30 min than baseline ( P < 0.0001. There was a significant decrease in heart rate ( P < 0.0001, and the average recovery time was 39.86 ± 12.22 min. Conclusion: Even though airway patency was maintained in all children sedated with dexmedetomidine, there were significant reductions in the upper airway dimensions measured, so all precautions to manage the airway failure should be taken.

  11. The effects of metronome breathing on the variability of autonomic activity measurements.

    Science.gov (United States)

    Driscoll, D; Dicicco, G

    2000-01-01

    Many chiropractors hypothesize that spinal manipulation affects the autonomic nervous system (ANS). However, the ANS responses to chiropractic manipulative therapy are not well documented, and more research is needed to support this hypothesis. This study represents a step toward the development of a reliable method by which to document that chiropractic manipulative therapy does affect the ANS by exploring the use of paced breathing as a way to reduce the inherent variability in ANS measurements. To examine the hypothesis that the variability of ANS measurements would be reduced if breathing were paced to a metronome at 12 breaths/min. The study was performed at Parker College Research Institute. Eight normotensive subjects were recruited from the student body and staff. Respiration frequency was measured through a strain gauge. A 3-lead electrocardiogram (ECG) was used to register the electric activity of the heart, and arterial tonometry monitors were used to record the left and right radial artery blood pressures. Signals were recorded on an IBM-compatible computer with a sampling frequency of 100 Hz. Normal breathing was used for the first 3 recordings, and breathing was paced to a metronome for the final 3 recordings at 12 breaths/min. Fourier analysis was performed on the beat-by-beat fluctuations of the ECG-determined R-R interval and systolic arterial pressure (SBP). Low-frequency fluctuations (LF; 0.04-0.15 Hz) reflected sympathetic activity, whereas high-frequency fluctuations (HF; 0.15-0.4 Hz) represented parasympathetic activity. Sympathovagal indices were determined from the ratio of the two bandwidths (LF/HF). The coefficient of variation (CV%) for autonomic parameters was calculated ([average/SD] x 100%) to compare breathing normally and breathing to a metronome with respect to variability. One-way analysis of variance was used to detect differences. A value of P Metronome breathing did not produce any significant changes in blood pressure for the

  12. pH in exhaled breath condensate and nasal lavage as a biomarker of air pollution-related inflammation in street traffic-controllers and office-workers

    Directory of Open Access Journals (Sweden)

    Thamires Marques de Lima

    2013-12-01

    Full Text Available OBJECTIVE: To utilize low-cost and simple methods to assess airway and lung inflammation biomarkers related to air pollution. METHODS: A total of 87 male, non-smoking, healthy subjects working as street traffic-controllers or office-workers were examined to determine carbon monoxide in exhaled breath and to measure the pH in nasal lavage fluid and exhaled breath condensate. Air pollution exposure was measured by particulate matter concentration, and data were obtained from fixed monitoring stations (8-h work intervals per day, during the 5 consecutive days prior to the study. RESULTS: Exhaled carbon monoxide was two-fold greater in traffic-controllers than in office-workers. The mean pH values were 8.12 in exhaled breath condensate and 7.99 in nasal lavage fluid in office-workers; these values were lower in traffic-controllers (7.80 and 7.30, respectively. Both groups presented similar cytokines concentrations in both substrates, however, IL-1β and IL-8 were elevated in nasal lavage fluid compared with exhaled breath condensate. The particulate matter concentration was greater at the workplace of traffic-controllers compared with that of office-workers. CONCLUSION: The pH values of nasal lavage fluid and exhaled breath condensate are important, robust, easy to measure and reproducible biomarkers that can be used to monitor occupational exposure to air pollution. Additionally, traffic-controllers are at an increased risk of airway and lung inflammation during their occupational activities compared with office-workers.

  13. Traditional Chinese herbal formula relieves snoring by modulating activities of upper airway related nerves in aged rats

    Directory of Open Access Journals (Sweden)

    Chung KT

    2018-05-01

    Full Text Available Kou-Toung Chung,* Chih-Hsiang Hsu,* Ching-Lung Lin, Sheue-Er Wang, Chung-Hsin WuDepartment of Life Science, National Taiwan Normal University, Taipei, Taiwan*These authors contributed equally to this workAim: The present study investigated whether intraperitoneal treatment with the herbal formula B210 ([B210]; a herbal composition of Gastrodia elata and Cinnamomum cassia can reduce snoring in aged rats. Also, we studied possible neural mechanisms involved in B210 treatment and subsequent reduced snoring in rats.Methods and result: We compared pressure and frequency of snoring, activities of phrenic nerve (PNA, activities of recurrent laryngeal nerve (RLNA and activities of hypoglossal nerve (HNA, inspiratory time (TI and expiratory time (TE of PNA, and pre-inspiratory time (Pre-TI of HNA in aged rats between sham and B210 treatment groups (30 mg/mL dissolved in DMSO. We found that aged rats that received B210 treatment had significantly reduced pressure and frequency of snoring than rats who received sham treatment. Also, we observed that aged rats that received B210 treatment had significantly increased PNA, RLNA, and HNA, extended TI and TE of PNA, and prolonged Pre-TI of HNA compared to rats that received sham treatment. In other words, B210 treatment may relieve snoring through modulating activities and breathing time of upper airway related nerves in aged rats.Conclusion: We suggested that the B210 might be a potential herbal formula for snoring remission.Keywords: Chinese herbal medicine, snoring remission, upper airway, phrenic nerve, recurrent laryngeal nerve, hypoglossal nerve

  14. The effects of progressive muscular relaxation and breathing control technique on blood pressure during pregnancy

    Directory of Open Access Journals (Sweden)

    Mahboobeh Aalami

    2016-01-01

    Full Text Available Background: Hypertensive disorders in pregnancy are the main cause of maternal and fetal mortality; however, they have no definite effective treatment. The researchers aimed to study the effects of progressive muscular relaxation and breathing control technique on blood pressure (BP during pregnancy. Materials and Methods: This three-group clinical trial was conducted in Mashhad health centers and governmental hospitals. Sixty pregnant (after 20 weeks of gestational age women with systolic BP ≥ 135 mmHg or diastolic BP ≥ 85 mmHg were assigned to three groups. Progressive muscular relaxation and breathing control exercises were administered to the two experimental groups once a week in person and in the rest of the days by instructions given on a CD for 4 weeks. BP was checked before and after the interventions. BP was measured before and after 15 min subjects' waiting without any especial intervention in the control group. Results: After 4 weeks of intervention, the systolic (by a mean of 131.3 to 117.2, P = 0.001 and by a mean of 131.05 to 120.5, P = 0.004, respectively and diastolic (by a mean of 79.2 to 72.3, P = 0.001 and by a mean of 80.1 to 76.5, P = 0.047, respectively BPs were significantly decreased in progressive muscular relaxation and breathing control groups, but they were not statistically significant in the control group. Conclusions: The interventions were effective on decreasing systolic and diastolic BP to normal range after 4 weeks in both the groups. The effects of both the interventions were more obvious on systolic BP compared to diastolic BP.

  15. The effect of obstructive sleep apnea and treatment with continuous positive airway pressure on stroke rehabilitation: rationale, design and methods of the TOROS study

    NARCIS (Netherlands)

    Aaronson, Justine A.; van Bennekom, Coen A. M.; Hofman, Winni F.; van Bezeij, Tijs; van den Aardweg, Joost G.; Groet, Erny; Kylstra, Wytske A.; Schmand, Ben A.

    2014-01-01

    Obstructive sleep apnea is a common sleep disorder in stroke patients. Obstructive sleep apnea is associated with stroke severity and poor functional outcome. Continuous positive airway pressure seems to improve functional recovery in stroke rehabilitation. To date, the effect of continuous positive

  16. News from the Breath Analysis Summit 2011.

    Science.gov (United States)

    Corradi, Massimo; Mutti, Antonio

    2012-06-01

    (oxygen, nitrogen, water vapour and CO(2)) in patient respiratory monitoring have served as a platform for technological growth in clinical breath-testing applications. A few exhaled breath tests have demonstrated clinical utility and are in widespread use, and several FDA-approved devices are available. These widely used exhaled breath tests include detection of blood alcohol concentration and exhaled CO(2). Other clinical applications of exhaled breath analysis include testing for H. pylori infection, lactose intolerance, heart transplant rejection and, more recently, monitoring of airway inflammation by means of exhaled NO. Examination of exhaled breath has the potential to change the existing routine approaches in human medicine. The rapidly developing new analytical and computer technologies along with novel, unorthodox ideas are prerequisites for future advances in this field. Scientists who participated in the Breath Analysis Summit 2011 were invited to submit a full length paper to the Journal of Breath Research and this issue includes eight articles which describe the different applications of breath analysis. We thank all the authors for their valuable contribution and we trust that this collection will provide useful information and an update to this rapidly evolving field, giving an example of integration among scientists who address the same topic-breath analysis-from different and complementary perspectives, from basic to clinical research.

  17. Computational Fluid Dynamics Modeling of Bacillus anthracis Spore Deposition in Rabbit and Human Respiratory Airways

    Energy Technology Data Exchange (ETDEWEB)

    Kabilan, Senthil; Suffield, Sarah R.; Recknagle, Kurtis P.; Jacob, Rick E.; Einstein, Daniel R.; Kuprat, Andrew P.; Carson, James P.; Colby, Sean M.; Saunders, James H.; Hines, Stephanie; Teeguarden, Justin G.; Straub, Tim M.; Moe, M.; Taft, Sarah; Corley, Richard A.

    2016-09-30

    Three-dimensional computational fluid dynamics and Lagrangian particle deposition models were developed to compare the deposition of aerosolized Bacillus anthracis spores in the respiratory airways of a human with that of the rabbit, a species commonly used in the study of anthrax disease. The respiratory airway geometries for each species were derived from computed tomography (CT) or µCT images. Both models encompassed airways that extended from the external nose to the lung with a total of 272 outlets in the human model and 2878 outlets in the rabbit model. All simulations of spore deposition were conducted under transient, inhalation-exhalation breathing conditions using average species-specific minute volumes. The highest exposure concentration was modeled in the rabbit based upon prior acute inhalation studies. For comparison, human simulation was also conducted at the same concentration. Results demonstrated that regional spore deposition patterns were sensitive to airway geometry and ventilation profiles. Due to the complex airway geometries in the rabbit nose, higher spore deposition efficiency was predicted in the upper conducting airways compared to the human at the same air concentration of anthrax spores. As a result, higher particle deposition was predicted in the conducting airways and deep lung of the human compared to the rabbit lung due to differences in airway branching pattern. This information can be used to refine published and ongoing biokinetic models of inhalation anthrax spore exposures, which currently estimate deposited spore concentrations based solely upon exposure concentrations and inhaled doses that do not factor in species-specific anatomy and physiology.

  18. Deep breathing exercises with positive expiratory pressure at a higher rate improve oxygenation in the early period after cardiac surgery--a randomised controlled trial.

    Science.gov (United States)

    Urell, Charlotte; Emtner, Margareta; Hedenström, Hans; Tenling, Arne; Breidenskog, Marie; Westerdahl, Elisabeth

    2011-07-01

    In addition to early mobilisation, a variety of breathing exercises are used to prevent postoperative pulmonary complications after cardiac surgery. The optimal duration of the treatment is not well evaluated. The aim of this study was to determine the effect of 30 versus 10 deep breaths hourly, while awake, with positive expiratory pressure on oxygenation and pulmonary function the first days after cardiac surgery. A total of 181 patients, undergoing cardiac surgery, were randomised into a treatment group, performing 30 deep breaths hourly the first postoperative days, or into a control group performing 10 deep breaths hourly. The main outcome measurement arterial blood gases and the secondary outcome pulmonary function, evaluated with spirometry, were determined on the second postoperative day. Preoperatively, both study groups were similar in terms of age, SpO(2), forced expiratory volume in 1s and New York Heart Association classification. On the second postoperative day, arterial oxygen tension (PaO(2)) was 8.9 ± 1.7 kPa in the treatment group and 8.1 ± 1.4 kPa in the control group (p = 0.004). Arterial oxygen saturation (SaO(2)) was 92.7 ± 3.7% in the treatment group and 91.1 ± 3.8% in the control group (p = 0.016). There were no differences in measured lung function between the groups or in compliance to the breathing exercises. Compliance was 65% of possible breathing sessions. A significantly increased oxygenation was found in patients performing 30 deep breaths the first two postoperative days compared with control patients performing 10 deep breaths hourly. These results support the implementation of a higher rate of deep breathing exercises in the initial phase after cardiac surgery. Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

  19. Evaluation of changes in sleep breathing patterns after primary palatoplasty in cleft children

    Directory of Open Access Journals (Sweden)

    Justice E. Reilly

    2014-09-01

    Full Text Available Introduction: There is a need to more clearly understand the characteristics of breathing patterns in children with cleft palate inthe first year of life, as there is little data available to guide current practice. Pierre Robin patients are known to have a higher incidence, however we hypothesised sleep breathing disturbance is not confined to this sub-group of cleft patient. Methods: We conducted a prospective observational study of sleep disordered breathing patterns in a cohort of infants with oronasal clefts (cleft palate with or without cleft lip to describe the spectrum of sleep breathing patterns both pre and post palate repair. Sleep breathing studies were performed pre- and post-operatively in sequential infants referred to a regional cleft lip andpalate unit. Results of sleep breathing studies were analysed according to American Academy of Sleep Medicine scoring guidelines and correlated with clinical history and details of peri-operative respiratory compromise. The degree of sleep disordered breathingwas characterised using desaturation indices (number of desaturations from baseline SpO2 of >=4%, per hour. Results: Thirty-nine infants were included in this study, twenty-five female and fourteen male. Twelve had isolated Cleft Palate aspart of an associated syndrome. Patients were categorised into Isolated Cleft Palate, Isolated Cleft Palate in the context of Pierre Robin Sequence, and those with Cleft Lip and Palate. All groups demonstrated some degree of sleep breathing abnormality. Not unsurprisingly the eight infants with Pierre Robin Sequence had a significantly higher desaturation index before surgicalintervention (p=0.043, and were more likely to require a pre-operative airway intervention (p=0.009. Palate repair in this group did not alter the relative distribution of patients in each severity category of sleep disorder breathing. Surgical repair ofthe secondary palate in the remaining children was associated with some

  20. Cardiorespiratory interactions during resistive load breathing.

    Science.gov (United States)

    Calabrese, P; Perrault, H; Dinh, T P; Eberhard, A; Benchetrit, G

    2000-12-01

    The addition to the respiratory system of a resistive load results in breathing pattern changes and in negative intrathoracic pressure increases. The aim of this study was to use resistive load breathing as a stimulus to the cardiorespiratory interaction and to examine the extent of the changes in heart rate variability (HRV) and respiratory sinus arrhythmia (RSA) in relation to the breathing pattern changes. HRV and RSA were studied in seven healthy subjects where four resistive loads were applied in a random order during the breath and 8-min recording made in each condition. The HRV spectral power components were computed from the R-R interval sequences, and the RSA amplitude and phase were computed from the sinusoid fitting the instantaneous heart rate within each breath. Adding resistive loads resulted in 1) increasing respiratory period, 2) unchanging heart rate, and 3) increasing HRV and changing RSA characteristics. HRV and RSA characteristics are linearly correlated to the respiratory period. These modifications appear to be linked to load-induced changes in the respiratory period in each individual, because HRV and RSA characteristics are similar at a respiratory period obtained either by loading or by imposed frequency breathing. The present results are discussed with regard to the importance of the breathing cycle duration in these cardiorespiratory interactions, suggesting that these interactions may depend on the time necessary for activation and dissipation of neurotransmitters involved in RSA.

  1. Effects of continuous positive airway pressure on neurocognitive function in obstructive sleep apnea patients: The Apnea Positive Pressure Long-term Efficacy Study (APPLES).

    Science.gov (United States)

    Kushida, Clete A; Nichols, Deborah A; Holmes, Tyson H; Quan, Stuart F; Walsh, James K; Gottlieb, Daniel J; Simon, Richard D; Guilleminault, Christian; White, David P; Goodwin, James L; Schweitzer, Paula K; Leary, Eileen B; Hyde, Pamela R; Hirshkowitz, Max; Green, Sylvan; McEvoy, Linda K; Chan, Cynthia; Gevins, Alan; Kay, Gary G; Bloch, Daniel A; Crabtree, Tami; Dement, William C

    2012-12-01

    To determine the neurocognitive effects of continuous positive airway pressure (CPAP) therapy on patients with obstructive sleep apnea (OSA). The Apnea Positive Pressure Long-term Efficacy Study (APPLES) was a 6-month, randomized, double-blind, 2-arm, sham-controlled, multicenter trial conducted at 5 U.S. university, hospital, or private practices. Of 1,516 participants enrolled, 1,105 were randomized, and 1,098 participants diagnosed with OSA contributed to the analysis of the primary outcome measures. Active or sham CPAP MEASUREMENTS: THREE NEUROCOGNITIVE VARIABLES, EACH REPRESENTING A NEUROCOGNITIVE DOMAIN: Pathfinder Number Test-Total Time (attention and psychomotor function [A/P]), Buschke Selective Reminding Test-Sum Recall (learning and memory [L/M]), and Sustained Working Memory Test-Overall Mid-Day Score (executive and frontal-lobe function [E/F]) The primary neurocognitive analyses showed a difference between groups for only the E/F variable at the 2 month CPAP visit, but no difference at the 6 month CPAP visit or for the A/P or L/M variables at either the 2 or 6 month visits. When stratified by measures of OSA severity (AHI or oxygen saturation parameters), the primary E/F variable and one secondary E/F neurocognitive variable revealed transient differences between study arms for those with the most severe OSA. Participants in the active CPAP group had a significantly greater ability to remain awake whether measured subjectively by the Epworth Sleepiness Scale or objectively by the maintenance of wakefulness test. CPAP treatment improved both subjectively and objectively measured sleepiness, especially in individuals with severe OSA (AHI > 30). CPAP use resulted in mild, transient improvement in the most sensitive measures of executive and frontal-lobe function for those with severe disease, which suggests the existence of a complex OSA-neurocognitive relationship. Registered at clinicaltrials.gov. Identifier: NCT00051363. Kushida CA; Nichols DA; Holmes

  2. Assessing breathing motion by shape matching of lung and diaphragm surfaces

    Science.gov (United States)

    Urschler, Martin; Bischof, Horst

    2005-04-01

    Studying complex thorax breating motion is an important research topic for accurate fusion of functional and anatomical data, radiotherapy planning or reduction of breathing motion artifacts. We investigate segmented CT lung, airway and diaphragm surfaces at several different breathing states between Functional Residual and Total Lung Capacity. In general, it is hard to robustly derive corresponding shape features like curvature maxima from lung and diaphragm surfaces since diaphragm and rib cage muscles tend to deform the elastic lung tissue such that e.g. ridges might disappear. A novel registration method based on the shape context approach for shape matching is presented where we extend shape context to 3D surfaces. The shape context approach was reported as a promising method for matching 2D shapes without relying on extracted shape features. We use the point correspondences for a non-rigid thin-plate-spline registration to get deformation fields that describe the movement of lung and diaphragm. Our validation consists of experiments on phantom and real sheep thorax data sets. Phantom experiments make use of shapes that are manipulated with known transformations that simulate breathing behaviour. Real thorax data experiments use a data set showing lungs and diaphragm at 5 distinct breathing states, where we compare subsets of the data sets and qualitatively and quantitatively asses the registration performance by using manually identified corresponding landmarks.

  3. Validation study of two-microphone acoustic reflectometry for determination of breathing tube placement in 200 adult patients.

    Science.gov (United States)

    Raphael, David T; Benbassat, Maxim; Arnaudov, Dimiter; Bohorquez, Alex; Nasseri, Bita

    2002-12-01

    Acoustic reflectometry allows the construction of a one-dimensional image of a cavity, such as the airway or the esophagus. The reflectometric area-distance profile consists of a constant cross-sectional area segment (length of endotracheal tube), followed either by a rapid increase in the area beyond the carina (tracheal intubation) or by an immediate decrease in the area (esophageal intubation). Two hundred adult patients were induced and intubated, without restrictions on anesthetic agents or airway adjunct devices. A two-microphone acoustic reflectometer was used to determine whether the breathing tube was placed in the trachea or esophagus. A blinded reflectometer operator, seated a distance away from the patient, interpreted the acoustic area-distance profile alone to decide where the tube was placed. Capnography was used as the gold standard. Of 200 tracheal intubations confirmed by capnography, the reflectometer operator correctly identified 198 (99% correct tracheal intubation identification rate). In two patients there were false-negative results, patients with a tracheal intubation were interpreted as having an esophageal intubation. A total of 14 esophageal intubations resulted, all correctly identified by reflectometry, for a 100% esophageal intubation identification rate. Acoustic reflectometry is a rapid, noninvasive method by which to determine whether breathing tube placement is correct (tracheal) or incorrect (esophageal). Reflectometry determination of tube placement may be useful in airway emergencies, particularly in cases where visualization of the glottic area is not possible and capnography may fail, as in patients with cardiac arrest.

  4. Impact of airway gas exchange on the multiple inert gas elimination technique: theory.

    Science.gov (United States)

    Anderson, Joseph C; Hlastala, Michael P

    2010-03-01

    The multiple inert gas elimination technique (MIGET) provides a method for estimating alveolar gas exchange efficiency. Six soluble inert gases are infused into a peripheral vein. Measurements of these gases in breath, arterial blood, and venous blood are interpreted using a mathematical model of alveolar gas exchange (MIGET model) that neglects airway gas exchange. A mathematical model describing airway and alveolar gas exchange predicts that two of these gases, ether and acetone, exchange primarily within the airways. To determine the effect of airway gas exchange on the MIGET, we selected two additional gases, toluene and m-dichlorobenzene, that have the same blood solubility as ether and acetone and minimize airway gas exchange via their low water solubility. The airway-alveolar gas exchange model simulated the exchange of toluene, m-dichlorobenzene, and the six MIGET gases under multiple conditions of alveolar ventilation-to-perfusion, VA/Q, heterogeneity. We increased the importance of airway gas exchange by changing bronchial blood flow, Qbr. From these simulations, we calculated the excretion and retention of the eight inert gases and divided the results into two groups: (1) the standard MIGET gases which included acetone and ether and (2) the modified MIGET gases which included toluene and m-dichlorobenzene. The MIGET mathematical model predicted distributions of ventilation and perfusion for each grouping of gases and multiple perturbations of VA/Q and Qbr. Using the modified MIGET gases, MIGET predicted a smaller dead space fraction, greater mean VA, greater log(SDVA), and more closely matched the imposed VA distribution than that using the standard MIGET gases. Perfusion distributions were relatively unaffected.

  5. Membrane Currents in Airway Smooth Muscle: Mechanisms and Therapeutic Implications

    Directory of Open Access Journals (Sweden)

    Luke J Janssen

    1997-01-01

    Full Text Available Electrophysiological and pharmacological techniques were used to characterize the membrane conductance changes underlying spasmogen-evoked depolarization in airway smooth muscle (ASM. Changes included a transient activation of chloride ion channels and prolonged suppression of potassium ion channels; both changes are triggered by release of internally sequestered calcium ion and in turn cause opening of voltage-dependent calcium channels. The resultant influx of calcium ions contributes to contraction as well as to refilling of the internal calcium ion pool. Bronchodilators, on the other hand, act in part through activation of potassium channels, with consequent closure of calcium channels. The tools used to study ion channels in ASM are described, and the investigations of the roles of ion channels in ASM physiology (autacoid-evoked depolarization and hyperpolarization and pathophysiology (airway hyperresponsiveness are summarized. Finally, how the relationship between ion channels and ASM function/dysfunction may relate to the treatment of asthma and related breathing disorders is discussed.

  6. Noninvasive CPAP with face mask: comparison among new air-entrainment masks and the Boussignac valve.

    Science.gov (United States)

    Mistraletti, Giovanni; Giacomini, Matteo; Sabbatini, Giovanni; Pinciroli, Riccardo; Mantovani, Elena S; Umbrello, Michele; Palmisano, Debora; Formenti, Paolo; Destrebecq, Anne L L; Iapichino, Gaetano

    2013-02-01

    The performances of 2 noninvasive CPAP systems (high flow and low flow air-entrainment masks) were compared to the Boussignac valve in 3 different scenarios. Scenario 1: pneumatic lung simulator with a tachypnea pattern (tidal volume 800 mL at 40 breaths/min). Scenario 2: Ten healthy subjects studied during tidal breaths and tachypnea. Scenario 3: Twenty ICU subjects enrolled for a noninvasive CPAP session. Differences between set and effective CPAP level and F(IO(2)), as well as the lowest airway pressure and the pressure swing around the imposed CPAP level, were analyzed. The lowest airway pressure and swing were correlated to the pressure-time product (area of the airway pressure curve below the CPAP level) measured with the simulator. P(aO(2)) was a subject's further performance index. Lung simulator: Boussignac F(IO(2)) was 0.54, even if supplied with pure oxygen. The air-entrainment masks had higher swing than the Boussignac (P = .007). Pressure-time product correlated better with pressure swing (Spearman correlation coefficient [ρ] = 0.97) than with lowest airway pressure (ρ = 0.92). In healthy subjects, the high-flow air-entrainment mask showed lower difference between set and effective F(IO(2)) (P mask had lower swing than the Boussignac valve (P = .03) with similar P(aO(2)) increase. High-flow air-entrainment mask showed the best performance in human subjects. During high flow demand, the Boussignac valve delivered lower than expected F(IO(2)) and showed higher dynamic hyper-pressurization than the air-entrainment masks. © 2013 Daedalus Enterprises.

  7. Airway smooth muscle cells : regulators of airway inflammation

    NARCIS (Netherlands)

    Zuyderduyn, Suzanne

    2007-01-01

    Airways from asthmatic subjects are more responsive to bronchoconstrictive stimuli than airways from healthy subjects. Airway smooth muscle (ASM) cells mediate contraction of the airways by responding to the bronchoconstrictive stimuli, which was thought to be the primary role of ASM cells. In this

  8. The Effect of mechanical resistive loading on optimal respiratory signals and breathing patterns under added dead space and CO2 breathing

    Directory of Open Access Journals (Sweden)

    Lin Shyan-Lung

    2016-01-01

    Full Text Available Current study aims to investigate how the respiratory resistive loading affects the behaviour of the optimal chemical-mechanical respiratory control model, the respiratory signals and breathing pattern are optimized under external dead space loading and CO2 breathing. The respiratory control was modelled to include a neuro-muscular drive as the control output to derive the waveshapes of instantaneous airflow, lung volume profiles, and breathing pattern, including total/alveolar ventilation, breathing frequency, tidal volume, inspiratory/expiratory duration, duty cycle, and arterial CO2 pressure. The simulations were performed under various respiratory resistive loads, including no load, inspiratory resistive load, expiratory resistive load, and continuous resistive load. The dead space measurement was described with Gray’s derivation, and simulation results were studied and compared with experimental findings.

  9. In vitro surfactant and perfluorocarbon aerosol deposition in a neonatal physical model of the upper conducting airways.

    Directory of Open Access Journals (Sweden)

    Estibalitz Goikoetxea

    Full Text Available OBJECTIVE: Aerosol delivery holds potential to release surfactant or perfluorocarbon (PFC to the lungs of neonates with respiratory distress syndrome with minimal airway manipulation. Nevertheless, lung deposition in neonates tends to be very low due to extremely low lung volumes, narrow airways and high respiratory rates. In the present study, the feasibility of enhancing lung deposition by intracorporeal delivery of aerosols was investigated using a physical model of neonatal conducting airways. METHODS: The main characteristics of the surfactant and PFC aerosols produced by a nebulization system, including the distal air pressure and air flow rate, liquid flow rate and mass median aerodynamic diameter (MMAD, were measured at different driving pressures (4-7 bar. Then, a three-dimensional model of the upper conducting airways of a neonate was manufactured by rapid prototyping and a deposition study was conducted. RESULTS: The nebulization system produced relatively large amounts of aerosol ranging between 0.3±0.0 ml/min for surfactant at a driving pressure of 4 bar, and 2.0±0.1 ml/min for distilled water (H2Od at 6 bar, with MMADs between 2.61±0.1 µm for PFD at 7 bar and 10.18±0.4 µm for FC-75 at 6 bar. The deposition study showed that for surfactant and H2Od aerosols, the highest percentage of the aerosolized mass (∼65% was collected beyond the third generation of branching in the airway model. The use of this delivery system in combination with continuous positive airway pressure set at 5 cmH2O only increased total airway pressure by 1.59 cmH2O at the highest driving pressure (7 bar. CONCLUSION: This aerosol generating system has the potential to deliver relatively large amounts of surfactant and PFC beyond the third generation of branching in a neonatal airway model with minimal alteration of pre-set respiratory support.

  10. Effectiveness and safety of a prehospital program of continuous positive airway pressure (CPAP) in an urban setting.

    Science.gov (United States)

    Willmore, Andrew; Dionne, Richard; Maloney, Justin; Ouston, Ed; Stiell, Ian

    2015-11-01

    Continuous positive airway pressure (CPAP) is commonly used in the treatment of acute cardiogenic pulmonary edema (ACPE) and acute exacerbations of chronic obstructive pulmonary disease (AECOPD). In-hospital evidence is robust: CPAP has been shown to improve respiratory status and to reduce intubation rates. There is less evidence on prehospital CPAP, although the emergency medical services (EMS) adoption of this modality is increasing. The objectives of this study were to 1) measure the effectiveness of prehospital CPAP on morbidity, mortality, and transport times; and 2) audit the selection of patients by medics for appropriateness and safety. We conducted a before-and-after study from August 1 to October 31 in 2010 and 2011, before and after the implementation of prehospital CPAP in a city of one million people with large rural areas. Medics were trained to apply CPAP to patients with respiratory distress and a presumed diagnosis of ACPE or AECOPD. Charts were selected using the search criteria of the chief complaint of shortness of breath, emergent transport to hospital, and any patients receiving CPAP in the field. Data extracted from ambulance call reports and hospital records were analysed with appropriate univariate statistics. A total of 373 patients enrolled (186 pre-non-invasive ventilation [NIV] and 187 post-NIV), mean age 71.5 years, female 51.4%, and final diagnoses of ACPE 18.9%, AECOPD 21.9%. In the post group of 84 patients meeting NIV criteria, 41.6% received NIV; and of 102 patients not meeting the criteria, 5.2% received NIV. There were 12 minor adverse events in 36 applications (33.3%) as per protocol. Comparing post versus pre, there were higher rates of emergency department (ED) NIV (20.0% v. 13.4%, pCPAP in our prehospital setting with respect to morbidity, mortality, and length of stay. EMS must exercise caution in making the decision to invest in the equipment and training required to implement prehospital CPAP.

  11. Validation of the System One RemStar Auto A-Flex for Obstructive Sleep Apnea Treatment and Detection of Residual Apnea-Hypopnea Index

    DEFF Research Database (Denmark)

    Gagnadoux, Frédéric; Pevernagie, Dirk; Jennum, Poul

    2017-01-01

    the performance of the System One RemStar Auto A-Flex (Philips Respironics, Murrysville, PA, USA) automatically adjusted positive airway pressure (APAP) mode to manually titrated, fixed pressure CPAP and to validate the device's breathing event detection capabilities against attended in-laboratory PSG. METHODS...

  12. Upper airway muscles awake and asleep.

    Science.gov (United States)

    Sériès, Frédéric

    2002-06-01

    Upper airway (UA) structures are involved in different respiratory and non-respiratory tasks. The coordination of agonist and antagonist UA dilators is responsible for their mechanical function and their ability to maintain UA patency throughout the respiratory cycle. The activity of these muscles is linked with central respiratory activity but also depends on UA pressure changes and is greatly influenced by sleep. UA muscles are involved in determining UA resistance and stability (i.e. closing pressure), and the effect of sleep on these variables may be accounted for by its effect on tonic and phasic skeletal muscle activities. The mechanical effects of UA dilator contraction also depend on their physiological properties (capacity to generate tension in vitro, activity of the anaerobic enzymatic pathway, histo-chemical characteristics that may differ between subjects who may or may not have sleep-related obstructive breathing disorders). These characteristics may represent an adaptive process to an increased resistive loading of these muscles. The apparent discrepancy between the occurrence of UA closure and an increased capacity to generate tension in sleep apnea patients may be due to a reduction in the effectiveness of UA muscle contraction in these patients; such an increase in tissue stiffness could be accounted for by peri-muscular tissue characteristics. Therefore, understanding of UA muscle physiological characteristics should take into account its capacity for force production and its mechanical coupling with other UA tissues. Important research goals for the future will be to integrate these issues with other physiological features of the disease, such as UA size and dimension, histological characteristics of UA tissues and the effect of sleep on muscle function. Such integration will better inform understanding of the role of pharyngeal UA muscles in the pathophysiology of the sleep apnea/hypopnea syndrome.

  13. Sleep disordered breathing in children with achondroplasia.

    Science.gov (United States)

    Zaffanello, Marco; Cantalupo, Gaetano; Piacentini, Giorgio; Gasperi, Emma; Nosetti, Luana; Cavarzere, Paolo; Ramaroli, Diego Alberto; Mittal, Aliza; Antoniazzi, Franco

    2017-02-01

    Children with achondroplasia often have breathing problems, especially during sleep. The most important treatments are adenotonsillectomy (for treating upper obstruction) and/or neurosurgery (for resolving cervicomedullar junction stenosis). We reviewed the scientific literature on polysomnographic investigations which assessed the severity of respiratory disorders during sleep. Recent findings have highlighted the importance of clinical investigations in patients with achondroplasia, differentiating between those that look for neurological patterns and those that look for respiratory problems during sleep. In particular, magnetic resonance imaging (MRI) and somatosensory evoked potentials are the main tools to evaluate necessary neurosurgery and over myelopathy, respectively. The use of polysomnography enables clinicians to identify children with upper airway obstruction and to quantify disease severity; it is not suitable for MRI and/or neurosurgery considerations.

  14. [The clinical effect of airway pressure release ventilation for acute lung injury/acute respiratory distress syndrome].

    Science.gov (United States)

    Song, Shaohua; Tian, Huiyu; Yang, Xiufen; Hu, Zhenjie

    2016-01-01

    To evaluate the effect of airway pressure release ventilation (APRV) in patients with acute lung injury/acute respiratory distress syndrome (ALI/ARDS), to evaluate the extent of ventilator-induced lung injury (VILI), and to explore its possible mechanism. A prospective study was conducted in the Department of Critical Care Medicine of the First Hospital of Hebei Medical University from December 2010 to February 2012. The patients with ALI/ARDS were enrolled. They were randomly divided into two groups. The patients in APRV group were given APRV pattern, while those in control group were given lung protection ventilation, synchronized intermittent mandatory ventilation with positive end-expiratory pressure (SIMV+PEEP). All patients were treated with AVEA ventilator. The parameters such as airway peak pressure (Ppeak), mean airway pressure (Pmean), pulse oxygen saturation (SpO2), mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), arterial blood gas, urine output (UO), the usage of sedation and muscle relaxation drugs were recorded. AVEA ventilator "turning point (Pflex) operation" was used to describe the quasi-static pressure volume curve (P-V curve). High and low inflection point (UIP, LIP) and triangular Pflex volume (Vdelta) were automatically measured and calculated. The ventilation parameters were set, and the 24-hour P-V curve was recorded again in order to be compared with subsequent results. Venous blood was collected before treatment, 24 hours and 48 hours after ventilation to measure lung surfactant protein D (SP-D) and large molecular mucus in saliva (KL-6) by enzyme linked immunosorbent assay (ELISA), and the correlation between the above two parameters and prognosis on 28 days was analyzed by multinomial logistic regression. Twenty-six patients with ALI/ARDS were enrolled, and 22 of them completed the test with 10 in APRV group and 12 in control group. The basic parameters and P-V curves between two groups were similar before

  15. Type of mask may impact on continuous positive airway pressure adherence in apneic patients.

    Directory of Open Access Journals (Sweden)

    Jean Christian Borel

    Full Text Available RATIONALE: In obstructive sleep apnea patients (OSA, continuous positive airway pressure (CPAP adherence is crucial to improve symptoms and cardiometabolic outcomes. The choice of mask may influence CPAP adherence but this issue has never been addressed properly. OBJECTIVE: To evaluate the impact of nasal pillows, nasal and oronasal masks on CPAP adherence in a cohort of OSA. METHODS: Newly CPAP treated OSA participating in "Observatoire Sommeil de la Fédération de Pneumologie", a French national prospective cohort, were included between March 2009 and December 2011. Anthropometric data, medical history, OSA severity, sleepiness, depressive status, treatment modalities (auto-CPAP versus fixed pressure, pressure level, interface type, use of humidifiers and CPAP-related side effects were included in multivariate analysis to determine independent variables associated with CPAP adherence. RESULTS: 2311 OSA (age = 57(12 years, apnea+hypopnea index = 41(21/h, 29% female were included. Nasal masks, oronasal masks and nasal pillows were used by 62.4, 26.2 and 11.4% of the patients, respectively. In univariate analysis, oronasal masks and nasal pillows were associated with higher risk of CPAP non-adherence. CPAP non-adherence was also associated with younger age, female gender, mild OSA, gastroesophageal reflux, depression status, low effective pressure and CPAP-related side effects. In multivariate analysis, CPAP non-adherence was associated with the use of oronasal masks (OR = 2.0; 95%CI = 1.6; 2.5, depression, low effective pressure, and side effects. CONCLUSION: As oronasal masks negatively impact on CPAP adherence, a nasal mask should be preferred as the first option. Patients on oronasal masks should be carefully followed.

  16. Type of mask may impact on continuous positive airway pressure adherence in apneic patients.

    Science.gov (United States)

    Borel, Jean Christian; Tamisier, Renaud; Dias-Domingos, Sonia; Sapene, Marc; Martin, Francis; Stach, Bruno; Grillet, Yves; Muir, Jean François; Levy, Patrick; Series, Frederic; Pepin, Jean-Louis

    2013-01-01

    In obstructive sleep apnea patients (OSA), continuous positive airway pressure (CPAP) adherence is crucial to improve symptoms and cardiometabolic outcomes. The choice of mask may influence CPAP adherence but this issue has never been addressed properly. To evaluate the impact of nasal pillows, nasal and oronasal masks on CPAP adherence in a cohort of OSA. Newly CPAP treated OSA participating in "Observatoire Sommeil de la Fédération de Pneumologie", a French national prospective cohort, were included between March 2009 and December 2011. Anthropometric data, medical history, OSA severity, sleepiness, depressive status, treatment modalities (auto-CPAP versus fixed pressure, pressure level, interface type, use of humidifiers) and CPAP-related side effects were included in multivariate analysis to determine independent variables associated with CPAP adherence. 2311 OSA (age = 57(12) years, apnea+hypopnea index = 41(21)/h, 29% female) were included. Nasal masks, oronasal masks and nasal pillows were used by 62.4, 26.2 and 11.4% of the patients, respectively. In univariate analysis, oronasal masks and nasal pillows were associated with higher risk of CPAP non-adherence. CPAP non-adherence was also associated with younger age, female gender, mild OSA, gastroesophageal reflux, depression status, low effective pressure and CPAP-related side effects. In multivariate analysis, CPAP non-adherence was associated with the use of oronasal masks (OR = 2.0; 95%CI = 1.6; 2.5), depression, low effective pressure, and side effects. As oronasal masks negatively impact on CPAP adherence, a nasal mask should be preferred as the first option. Patients on oronasal masks should be carefully followed.

  17. The classical Starling resistor model often does not predict inspiratory airflow patterns in the human upper airway.

    Science.gov (United States)

    Owens, Robert L; Edwards, Bradley A; Sands, Scott A; Butler, James P; Eckert, Danny J; White, David P; Malhotra, Atul; Wellman, Andrew

    2014-04-15

    The upper airway is often modeled as a classical Starling resistor, featuring a constant inspiratory airflow, or plateau, over a range of downstream pressures. However, airflow tracings from clinical sleep studies often show an initial peak before the plateau. To conform to the Starling model, the initial peak must be of small magnitude or dismissed as a transient. We developed a method to simulate fast or slow inspirations through the human upper airway, to test the hypothesis that this initial peak is a transient. Eight subjects [4 obstructive sleep apnea (OSA), 4 controls] slept in an "iron lung" and wore a nasal mask connected to a continuous/bilevel positive airway pressure machine. Downstream pressure was measured using an epiglottic catheter. During non-rapid eye movement (NREM) sleep, subjects were hyperventilated to produce a central apnea, then extrathoracic pressure was decreased slowly (∼2-4 s) or abruptly (resistor model, the upper airway exhibits marked NED in some subjects.

  18. Computational fluid dynamics modeling of Bacillus anthracis spore deposition in rabbit and human respiratory airways

    Energy Technology Data Exchange (ETDEWEB)

    Kabilan, S.; Suffield, S. R.; Recknagle, K. P.; Jacob, R. E.; Einstein, D. R.; Kuprat, A. P.; Carson, J. P.; Colby, S. M.; Saunders, J. H.; Hines, S. A.; Teeguarden, J. G.; Straub, T. M.; Moe, M.; Taft, S. C.; Corley, R. A.

    2016-09-01

    Three-dimensional computational fluid dynamics and Lagrangian particle deposition models were developed to compare the deposition of aerosolized Bacillus anthracis spores in the respiratory airways of a human with that of the rabbit, a species commonly used in the study of anthrax disease. The respiratory airway geometries for each species were derived respectively from computed tomography (CT) and µCT images. Both models encompassed airways that extended from the external nose to the lung with a total of 272 outlets in the human model and 2878 outlets in the rabbit model. All simulations of spore deposition were conducted under transient, inhalation–exhalation breathing conditions using average species-specific minute volumes. Two different exposure scenarios were modeled in the rabbit based upon experimental inhalation studies. For comparison, human simulations were conducted at the highest exposure concentration used during the rabbit experimental exposures. Results demonstrated that regional spore deposition patterns were sensitive to airway geometry and ventilation profiles. Due to the complex airway geometries in the rabbit nose, higher spore deposition efficiency was predicted in the nasal sinus compared to the human at the same air concentration of anthrax spores. In contrast, higher spore deposition was predicted in the lower conducting airways of the human compared to the rabbit lung due to differences in airway branching pattern. This information can be used to refine published and ongoing biokinetic models of inhalation anthrax spore exposures, which currently estimate deposited spore concentrations based solely upon exposure concentrations and inhaled doses that do not factor in species-specific anatomy and physiology for deposition.

  19. Auto-titrating versus fixed continuous positive airway pressure for the treatment of obstructive sleep apnea: a systematic review with meta-analyses

    Directory of Open Access Journals (Sweden)

    Ip Stanley

    2012-03-01

    Full Text Available Abstract Background Obstructive sleep apnea is a relatively common disorder that can lead to lost productivity and cardiovascular disease. The form of positive airway treatment that should be offered is unclear. Methods MEDLINE and the Cochrane Central Trials registry were searched for English language randomized controlled trials comparing auto-titrating positive airway pressure (APAP with continuous positive airway pressure (CPAP in adults with obstructive sleep apnea (inception through 9/2010. Six researchers extracted information on study design, potential bias, patient characteristics, interventions and outcomes. Data for each study were extracted by one reviewer and confirmed by another. Random effects model meta-analyses were performed for selected outcomes. Results Twenty-four randomized controlled trials met the inclusion criteria. In individual studies, APAP and fixed CPAP resulted in similar changes from baseline in the apnea-hypopnea index, most other sleep study measures and quality of life. By meta-analysis, APAP improved compliance by 11 minutes per night (95% CI, 3 to 19 minutes and reduced sleepiness as measured by the Epworth Sleepiness Scale by 0.5 points (95% CI, 0.8 to 0.2 point reduction compared with fixed CPAP. Fixed CPAP improved minimum oxygen saturation by 1.3% more than APAP (95% CI, 0.4 to 2.2%. Studies had relatively short follow-up and generally excluded patients with significant comorbidities. No study reported on objective clinical outcomes. Conclusions Statistically significant differences were found but clinical importance is unclear. Because the treatment effects are similar between APAP and CPAP, the therapy of choice may depend on other factors such as patient preference, specific reasons for non-compliance and cost.

  20. The effect of disease and respiration on airway shape in patients with moderate persistent asthma.

    Directory of Open Access Journals (Sweden)

    Spyridon Montesantos

    Full Text Available Computational models of gas transport and aerosol deposition frequently utilize idealized models of bronchial tree structure, where airways are considered a network of bifurcating cylinders. However, changes in the shape of the lung during respiration affect the geometry of the airways, especially in disease conditions. In this study, the internal airway geometry was examined, concentrating on comparisons between mean lung volume (MLV and total lung capacity (TLC. A set of High Resolution CT images were acquired during breath hold on a group of moderate persistent asthmatics at MLV and TLC after challenge with a broncho-constrictor (methacholine and the airway trees were segmented and measured. The airway hydraulic diameter (Dh was calculated through the use of average lumen area (Ai and average internal perimeter (Pi at both lung volumes and was found to be systematically higher at TLC by 13.5±9% on average, with the lower lobes displaying higher percent change in comparison to the lower lobes. The average internal diameter (Din was evaluated to be 12.4±6.8% (MLV and 10.8±6.3% (TLC lower than the Dh, for all the examined bronchi, a result displaying statistical significance. Finally, the airway distensibility per bronchial segment and per generation was calculated to have an average value of 0.45±0.28, exhibiting high variability both between and within lung regions and generations. Mixed constriction/dilation patterns were recorded between the lung volumes, where a number of airways either failed to dilate or even constricted when observed at TLC. We conclude that the Dh is higher than Din, a fact that may have considerable effects on bronchial resistance or airway loss at proximal regions. Differences in caliber changes between lung regions are indicative of asthma-expression variability in the lung. However, airway distensibility at generation 3 seems to predict distensibility more distally.

  1. Effects of continuous positive airway pressure on energy intake in obstructive sleep apnea: A pilot sham-controlled study

    OpenAIRE

    Shechter, Ari; Kovtun, Kyle; St-Onge, Marie-Pierre

    2016-01-01

    Obesity is among the leading risk factors for obstructive sleep apnea (OSA). A reciprocal relationship between obesity and OSA has been proposed, which may be due to excessive food intake. We conducted a pilot study to test the effects of continuous positive airway pressure (CPAP) on energy intake (EI) in OSA patients using a sham-controlled crossover design. In-laboratory total daily EI was assessed after 2 mo of active and sham CPAP. Four men were enrolled (age ± SEM: 51.8 ± 2.1 y; body mas...

  2. Noninvasive ventilation in patients with acute cardiogenic pulmonary edema

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    Andrea Bellone

    2013-07-01

    Full Text Available The term noninvasive ventilation (NIV encompasses two different modes of delivering positive airway pressure, namely continuous positive airway pressure (CPAP and bilevel positive airway pressure (bilevel-PAP. The two modes are different since CPAP does not actively assist inspiration whereas bilevel-PAP does. Bilevel-PAP is a type of noninvasive ventilation that helps keep the upper airways of the lungs open by providing a flow of air delivered through a face mask. The air is pressurized by a machine, which delivers it to the face mask through long, plastic hosing. With bilevel-PAP, the doctor prescribes specific alternating pressures: a higher pressure is used to breathe in (inspiratory positive airway pressure and a lower pressure is used to breath out (expiratory positive airway pressure. Noninvasive ventilation has been shown to reduce the rate of tracheal intubation. The main indications are exacerbation of chronic obstructive pulmonary disease and acute cardiogenic pulmonary edema (ACPE. This last is a common cause of respiratory failure with high incidence and high mortality rate. Clinical findings of ACPE are related to the increased extra-vascular water in the lungs and the resulting reduced lung compliance, increased airway resistance and elevated inspiratory muscle load which generates a depression in pleural pressure. These large pleural pressure swings are responsible for hemodynamic changes by increasing left ventricular afterload, myocardial transmural pressure, and venous return. These alterations can be detrimental to patients with left ventricular systolic dysfunction. Under these circumstances, NIV, either by CPAP or bilevel-PAP, improves vital signs, gas exchange, respiratory mechanics and hemodynamics by reducing left ventricular afterload and preload. In the first randomized study which compared the effectiveness of CPAP plus medical treatment vs medical treatment alone, the CPAP group showed a significant decrease in its

  3. Intrathoracic pressure regulation during cardiopulmonary resuscitation: a feasibility case-series.

    Science.gov (United States)

    Segal, Nicolas; Parquette, Brent; Ziehr, Jonathon; Yannopoulos, Demetris; Lindstrom, David

    2013-04-01

    Intrathoracic pressure regulation (IPR) is a novel, noninvasive therapy intended to increase cardiac output and blood pressure in hypotensive states by generating a negative end expiratory pressure of -12 cm H2O between positive pressure ventilations. In this first feasibility case-series, we tested the hypothesis that IPR improves End tidal (ET) CO2 during cardiopulmonary resuscitation (CPR). ETCO2 was used as a surrogate measure for circulation. All patients were treated initially with manual CPR and an impedance threshold device (ITD). When IPR-trained medics arrived on scene the ITD was removed and an IPR device (CirQLATOR™) was attached to the patient's advanced airway (intervention group). The IPR device lowered airway pressures to -9 mmHg after each positive pressure ventilation for the duration of the expiratory phase. ETCO2, was measured using a capnometer incorporated into the defibrillator system (LifePak™). Values are expressed as mean ± SEM. Results were compared using paired and unpaired Student's t test. p values of <0.05 were considered statistically significant. ETCO2 values in 11 patients in the case series were compared pre and during IPR therapy and also compared to 74 patients in the control group not treated with the new IPR device. ETCO2 values increased from an average of 21 ± 1 mmHg immediately before IPR application to an average value of 32 ± 5 mmHg and to a maximum value of 45 ± 5mmHg during IPR treatment (p<0.001). In the control group ETCO2 values did not change significantly. Return of spontaneous circulation (ROSC) rates were 46% (34/74) with standard CPR and ITD versus 73% (8/11) with standard CPR and the IPR device (p<0.001). ETCO2 levels and ROSC rates were significantly higher in the study intervention group. These findings demonstrate that during CPR circulation may be significantly augmented by generation of a negative end expiratory pressure between each breath. Copyright © 2012 Elsevier Ireland Ltd. All rights

  4. [Manual airway clearance techniques in adults and adolescents: What level of evidence?

    Science.gov (United States)

    Cabillic, Michel; Gouilly, Pascal; Reychler, Gregory

    2016-04-13

    The aim of this systematic literature review was to grade the levels of evidence of the most widely used manual airway clearance techniques. A literature search was conducted over the period 1995-2014 from the Medline, PEDro, ScienceDirect, Cochrane Library, REEDOC and kinedoc databases, with the following keywords: "postural drainage", "manual vibrations", "manual chest percussion", "directed cough", "increased expiratory flow", "ELTGOL", "autogenic drainage" and "active cycle of breathing technique". Two-hundred and fifty-six articles were identified. After removing duplicates and reading the titles and abstracts, 63 articles were selected, including 9 systematic reviews. This work highlights the lack of useful scientific data and the difficulty of determining levels of evidence for manual airway clearance techniques. Techniques were assessed principally with patients with sputum production (cystic fibrosis, DDB, COPD, etc.). It also shows the limited pertinence of outcome measures to quantify congestion and hence the efficacy of airway clearance techniques. The 1994 consensus conference summary table classifying airway clearance techniques according to physical mechanism provides an interesting tool for assessment, grouping together techniques having identical mechanisms of action. From the findings of the present systematic review, it appears that only ELTGOL, autogenic drainage and ACBT present levels of evidence "B". All other techniques have lower levels of evidence. II. Copyright © 2016. Published by Elsevier Masson SAS.

  5. Bubble vs conventional continuous positive airway pressure for prevention of extubation failure in preterm very low birth weight infants: a pilot study.

    Science.gov (United States)

    Yadav, Sucheta; Thukral, Anu; Sankar, M Jeeva; Sreenivas, V; Deorari, Ashok K; Paul, Vinod K; Agarwal, Ramesh

    2012-09-01

    To compare the efficacy of bubble and conventional nasal continuous positive airway pressure (CPAP) in preventing extubation failure (EF) in preterm infants. Infants of gestation ≤32 wk and birth weight <1500 g, ready for initial extubation within first wk of life were randomly allocated to either bubble (n = 16) or conventional (n = 16) CPAP. A standardized protocol was used for extubation. Bubble CPAP was delivered by Fischer and Paykel equipment using short binasal prongs and conventional CPAP was delivered by a ventilator using Argyle short binasal prongs. CPAP was initiated at a pressure of 4-6 cm of H(2)O and FiO(2) of 0.4-0.5 and adjusted to maintain normal saturation (90-93%) and comfortable breathing. Primary outcome was EF, defined as need for mechanical ventilation within 72 h of extubation. Baseline characteristics including birth weight (g; 1027 ± 243 vs. 1018 ± 227; p = 0.83), gestation (wk; 28.7 ± 1.8 vs. 28.4 ± 1.6; p = 0.30), infants <28 wk gestation (6 vs. 7, p = 0.72) were comparable between the two groups. Respiratory distress syndrome was the indication for ventilation in 13 (81%) and 14 (87%) infants on bubble CPAP and conventional CPAP groups respectively. (p = 0.99). There was no difference in the EF rates between the bubble (n = 4) and conventional CPAP (n = 9) groups. (RR 0.49; 95% CI 0.20-1.2; p = 0.14). Median time to extubation failure was also comparable between the two groups (h; median [range]: 29 [14-49] vs. 17 [7-28]; p = 0.35). The possibility that bubble CPAP may be associated with reduced EF as suggested in this pilot study requires further investigation in an adequately powered multicentric study.

  6. Double blind randomised controlled trial of two different breathing techniques in the management of asthma.

    Science.gov (United States)

    Slader, C A; Reddel, H K; Spencer, L M; Belousova, E G; Armour, C L; Bosnic-Anticevich, S Z; Thien, F C K; Jenkins, C R

    2006-08-01

    Previous studies have shown that breathing techniques reduce short acting beta(2) agonist use and improve quality of life (QoL) in asthma. The primary aim of this double blind study was to compare the effects of breathing exercises focusing on shallow nasal breathing with those of non-specific upper body exercises on asthma symptoms, QoL, other measures of disease control, and inhaled corticosteroid (ICS) dose. This study also assessed the effect of peak flow monitoring on outcomes in patients using breathing techniques. After a 2 week run in period, 57 subjects were randomised to one of two breathing techniques learned from instructional videos. During the following 30 weeks subjects practised their exercises twice daily and as needed for relief of symptoms. After week 16, two successive ICS downtitration steps were attempted. The primary outcome variables were QoL score and daily symptom score at week 12. Overall there were no clinically important differences between the groups in primary or secondary outcomes at weeks 12 or 28. The QoL score remained unchanged (0.7 at baseline v 0.5 at week 28, p = 0.11 both groups combined), as did lung function and airway responsiveness. However, across both groups, reliever use decreased by 86% (p0.10 between groups). Peak flow monitoring did not have a detrimental effect on asthma outcomes. Breathing techniques may be useful in the management of patients with mild asthma symptoms who use a reliever frequently, but there is no evidence to favour shallow nasal breathing over non-specific upper body exercises.

  7. Avaliação do teste de respiração espontânea na extubação de neonatos pré-termo Spontaneous breathing trial evaluation in preterm newborns extubation

    Directory of Open Access Journals (Sweden)

    Lívia Barboza Andrade

    2010-06-01

    workload. The spontaneous breathing trial (SBT, performed immediately before extubation, can provide useful information on the patient's spontaneous breathing ability. This study aimed to assess the SBT effectiveness for extubation success prediction in mechanically ventilated preterm infants. METHODS: After Ethics Committee approval, an observational, longitudinal, prospective study was conducted. A sample of 60 preterm infants compliant with the weaning criteria was categorized in two groups: 'SBT' group (n=30, with the patients who underwent 30 minutes spontaneous breathing trial (SBT with continuous positive pressure airway (CPAP, and the control group (n=30 where the extubation was performed without spontaneous breathing trial. The heart rate (HR, respiratory rate (RR, pulse oxymetry oxygen saturation (SpO2 and the Silverman-Andersen score were recorded before and 10, 20 and 30 minutes after the spontaneous breathing trial. Were also assessed for both groups, and versus extubation success or failure, the weight, gestational age, Apgar score, mean airway pressure, inspired oxygen concentration, and tracheal tube time. The Chi-square test was used for categorical variables and the Mann-Whitney test for non-normal distribution. Extubation success was defined as a 48 hours period with no reintubation requirement. RESULTS: No significant differences were identified between the groups for the analyzed variables, except for the mean airway pressure. A significant association was shown between spontaneous breathing trial and successful extubation. CONCLUSION: The significant association between SBT and extubation success may contribute for prediction of successful weaning in preterm infants.

  8. A 64-year old man who sustained many episodes of acute cardiogenic pulmonary edema successfully treated with Boussignac continuous positive airway pressure : A case report

    NARCIS (Netherlands)

    Dieperink, Willem; van der Horst, Iwan C. C.; Nannenberg-Koops, Jaqueline W.; Brouwer, Henk W.; Jaarsma, T.; Nieuwland, Wybe; Zijlstra, Felix; Nijsten, Maarten W. N.

    2007-01-01

    Continuous positive airway pressure (CPAP) is standard treatment for patients with acute cardiogenic pulmonary edema. We describe a patient who had 21 episodes of acute cardiogenic pulmonary edema due to very poor patient compliance. This 64-year old man had end-stage congestive heart failure based

  9. Regional aerosol deposition in human upper airways

    International Nuclear Information System (INIS)

    Swift, D.L.

    1989-01-01

    During the report period significant progress on the quantitative understanding of regional upper airway deposition of airborne particle has been realized. Replicate models of the human upper airways obtained from post-mortem casting of the nasal, oral, pharyngeal, laryngeal and upper tracheal regions and in vivo magnetic resonance imaging (MRI) of the same regions of adults and children have been employed to determine the overall and local deposition characteristics of aerosols in the ultrafine (1--100 μm diameter) and fine (0.8--12 μm diameter) region. Studies have been carried out for both nasal and oral breathing during inspiratory and expiratory flow at constant flow rates representative of rest and states of exercise. The results of these investigations indicate that particles in the size range of ''unattached'' radon progeny (1--3 nm) are deposited in both the nasal and oral passages with high efficiency (60--80%) for both inspiration and expiration, with the nasal deposition being somewhat greater (5--10%) than oral deposition. The effect of flow rate on upper airway deposition for both pathways is not great; data analysis indicates that the deposition for all flow rates from 4--50 liters/minute can be grouped by plotting deposition vs Q- 1/8 , where Q is flow rate, a far weaker dependency than observed for inertial deposition. Diffusional transport is the primary mechanism of deposition, and size dependence can be accounted for by plotting, deposition percent vs D n where D is particle diffusion coefficient and n ranges from 0.5--0.66. 2 refs

  10. Exhaled breath condensate nitrates, but not nitrites or FENO, relate to asthma control.

    Science.gov (United States)

    Malinovschi, Andrei; Pizzimenti, Stefano; Sciascia, Savino; Heffler, Enrico; Badiu, Iuliana; Rolla, Giovanni

    2011-07-01

    Asthma is a chronic respiratory disease, characterised by airways inflammation, obstruction and hyperresponsiveness. Asthma control is the goal of asthma treatment, but many patients have sub-optimal control. Exhaled NO and exhaled breath condensate (EBC) NO metabolites (nitrites and nitrates) measurements are non-invasive tools to assess airways inflammation. Our aim was to investigate the relationships between asthma control and the above-named biomarkers of airways inflammation. Thirty-nine non-smoking asthmatic patients (19 women) aged 50 (21-80) years performed measurements of exhaled NO (FENO), EBC nitrates, nitrites and pH, and answered Asthma Control Questionnaire (ACQ) and Asthma Control Test (ACT)-questionnaire. The ACT and ACQ score were strongly interrelated (ρ = -0.84, p 0.05). EBC nitrates were negatively related to ACT score (ρ = -0.34, p = 0.03) and positively related to ACQ score (ρ = 0.41, p = 0.001) while no relation of EBC nitrites to either ACQ or ACT score was found (p>0.05). EBC nitrates were the only biomarker that was significantly related to asthma control. This suggests that nitrates, but not nitrites or FENO, reflect an aspect of airways inflammation that is closer related to asthma symptoms. Therefore there is a potential role for EBC nitrates in objective assessment of asthma control. Copyright © 2010 Elsevier Ltd. All rights reserved.

  11. Management of Sleep Disordered Breathing in Patients with Heart Failure.

    Science.gov (United States)

    Oates, Connor P; Ananthram, Manjula; Gottlieb, Stephen S

    2018-04-03

    This paper reviews treatment options for sleep disordered breathing (SDB) in patients with heart failure. We sought to identify therapies for SDB with the best evidence for long-term use in patients with heart failure and to minimize uncertainties in clinical practice by examining frequently discussed questions: what is the role of continuous positive airway pressure (CPAP) in patients with heart failure? Is adaptive servo-ventilation (ASV) safe in patients with heart failure? To what extent is SDB a modifiable risk factor? Consistent evidence has demonstrated that the development of SDB in patients with heart failure is a poor prognostic indicator and a risk factor for cardiovascular mortality. However, despite numerous available interventions for obstructive sleep apnea and central sleep apnea, it remains unclear what effect these therapies have on patients with heart failure. To date, all major randomized clinical trials have failed to demonstrate a survival benefit with SDB therapy and one major study investigating the use of adaptive servo-ventilation demonstrated harm. Significant questions persist regarding the management of SDB in patients with heart failure. Until appropriately powered trials identify a treatment modality that increases cardiovascular survival in patients with SDB and heart failure, a patient's heart failure management should remain the priority of medical care.

  12. Deposition of inhaled radionuclides in bronchial airways: Implications for extrapolation modeling

    International Nuclear Information System (INIS)

    Balashazy, I.; Hofmann, W.; Heistracher, T.

    1996-01-01

    The laboratory rat has frequently been used as a human surrogate to estimate potential health effects following the inhalation of radioactive aerosol particles. Interspecies differences in biological response are commonly related to interspecies differences in particle deposition efficiencies. In addition, the documented site selectivity of bronchial carcinomas suggests that localized particle deposition patterns within bronchial airway bifurcations may have important implications for inhalation risk assessments. Interspecies differences in particle deposition patterns may be related primarily to differences in airway morphometries. Thus the validity of extrapolating rat deposition data to human inhalation conditions depends on their morphometric similarities and differences. It is well known that there are significant structural differences between the human - rather symmetric - and the rat - monopodial - airway systems. In the present approach, we focus on localized deposition patterns and deposition efficiencies in selected asymmetric bronchial airway bifurcations, whose diameters, lengths and branching angles were derived from the stochastic airway models of human and rat lungs (Koblinger and Hofmann, 1985;1988), which are based on the morphometric data of Raabe et al. (1976). The effects of interspecies differences in particle deposition patterns are explored in this study for two asymmetric bifurcation geometries in segmental bronchi and terminal bronchioles of both the human and rat lungs at different particle sizes. In order to examine the effect of flow rate on particle deposition in the human lung, we selected two different minute volumes, i.e., 10 and 60 1 min -1 , which are representative of low and heavy physical activity breathing conditions. In the case of the rat we used a minute volume of 0.234 1 min -1 (Hofmann et al., 1993)

  13. Magnetic resonance imaging in children: common problems and possible solutions for lung and airways imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ciet, Pierluigi; Tiddens, Harm A.W.M. [Erasmus Medical Center, Department of Radiology, Sophia Children' s Hospital, Rotterdam (Netherlands); Erasmus Medical Center, Department of Pediatric Pulmonology and Allergology, Sophia Children' s Hospital, Rotterdam (Netherlands); Wielopolski, Piotr A. [Erasmus Medical Center, Department of Radiology, Sophia Children' s Hospital, Rotterdam (Netherlands); Wild, Jim M. [University of Sheffield, Academic Radiology, Sheffield (United Kingdom); Lee, Edward Y. [Boston Children' s Hospital and Harvard Medical School, Departments of Radiology and Medicine, Pulmonary Divisions, Boston, MA (United States); Morana, Giovanni [Ca' Foncello Regional Hospital, Department of Radiology, Treviso (Italy); Lequin, Maarten H. [University Medical Center, Department of Radiology, Wilhelmina Children' s Hospital, Utrecht (Netherlands)

    2015-12-15

    Pediatric chest MRI is challenging. High-resolution scans of the lungs and airways are compromised by long imaging times, low lung proton density and motion. Low signal is a problem of normal lung. Lung abnormalities commonly cause increased signal intensities. Among the most important factors for a successful MRI is patient cooperation, so the long acquisition times make patient preparation crucial. Children usually have problems with long breath-holds and with the concept of quiet breathing. Young children are even more challenging because of higher cardiac and respiratory rates giving motion blurring. For these reasons, CT has often been preferred over MRI for chest pediatric imaging. Despite its drawbacks, MRI also has advantages over CT, which justifies its further development and clinical use. The most important advantage is the absence of ionizing radiation, which allows frequent scanning for short- and long-term follow-up studies of chronic diseases. Moreover, MRI allows assessment of functional aspects of the chest, such as lung perfusion and ventilation, or airways and diaphragm mechanics. In this review, we describe the most common MRI acquisition techniques on the verge of clinical translation, their problems and the possible solutions to make chest MRI feasible in children. (orig.)

  14. Intratidal Overdistention and Derecruitment in the Injured Lung: A Simulation Study.

    Science.gov (United States)

    Amini, Reza; Herrmann, Jacob; Kaczka, David W

    2017-03-01

    Ventilated patients with the acute respiratory distress syndrome (ARDS) are predisposed to cyclic parenchymal overdistention and derecruitment, which may worsen existing injury. We hypothesized that intratidal variations in global mechanics, as assessed at the airway opening, would reflect such distributed processes. We developed a computational lung model for determining local instantaneous pressure distributions and mechanical impedances continuously during a breath. Based on these distributions and previous literature, we simulated the within-breath variability of airway segment dimensions, parenchymal viscoelasticity, and acinar recruitment in an injured canine lung for tidal volumes( V T ) of 10, 15, and 20 mL·kg -1 and positive end-expiratory pressures (PEEP) of 5, 10, and 15 cm H 2 O. Acini were allowed to transition between recruited and derecruited states when exposed to stochastically determined critical opening and closing pressures, respectively. For conditions of low V T and low PEEP, we observed small intratidal variations in global resistance and elastance, with a small number of cyclically recruited acini. However, with higher V T and PEEP, larger variations in resistance and elastance were observed, and the majority of acini remained open throughout the breath. Changes in intratidal resistance, elastance, and impedance followed well-defined parabolic trajectories with tracheal pressure, achieving minima near 12 to 16 cm H 2 O. Intratidal variations in lung mechanics may allow for optimization of ventilator settings in patients with ARDS, by balancing lung recruitment against parenchymal overdistention. Titration of airway pressures based on variations in intratidal mechanics may mitigate processes associated with injurious ventilation.

  15. ProSeal laryngeal mask airway as an alternative to standard endotracheal tube in securing upper airway in the patients undergoing beating-heart coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Kalpana Shah

    2017-01-01

    Full Text Available Background: ProSeal laryngeal mask airways (PLMAs are routinely used after failed tracheal intubation as airway rescue, facilitating tracheal intubation by acting as a conduit and to secure airway during emergencies. In long duration surgeries, use of endotracheal tube (ETT is associated with various hemodynamic complications, which are minimally affected during PLMA use. However, except for few studies, there are no significant data available that promote the use of laryngeal mask during cardiac surgery. This prospective study was conducted with the objective of demonstrating the advantages of PLMA over ETT in the patients undergoing beating-heart coronary artery bypass graft (CABG. Methodology: This prospective, interventional study was carried out in 200 patients who underwent beating-heart CABG. Patients were randomized in equal numbers to either ETT group or PLMA group, and various hemodynamic and respiratory parameters were observed at different time points. Results: Patients in PLMA group had mean systolic blood pressure 126.10 ± 5.31 mmHg compared to the patients of ETT group 143.75 ± 6.02 mmHg. Pulse rate in the PLMA group was less (74.52 ± 10.79 per min (P < 0.05 compared to ETT group (81.72 ± 9.8. Thus, hemodynamic changes were significantly lower (P < 0.05 in PLMA than in ETT group. Respiratory parameters such as oxygen saturation, pressure CO 2 (pCO 2 , peak airway pressure, and lung compliance were similar to ETT group at all evaluation times. The incidence of adverse events was also lower in PLMA group. Conclusion: In experience hand, PLMA offers advantages over the ETT in airway management in the patients undergoing beating-heart CABG.

  16. Effect of parenchymal stiffness on canine airway size with lung inflation.

    Directory of Open Access Journals (Sweden)

    Robert H Brown

    2010-04-01

    Full Text Available Although airway patency is partially maintained by parenchymal tethering, this structural support is often ignored in many discussions of asthma. However, agonists that induce smooth muscle contraction also stiffen the parenchyma, so such parenchymal stiffening may serve as a defense mechanism to prevent airway narrowing or closure. To quantify this effect, specifically how changes in parenchymal stiffness alter airway size at different levels of lung inflation, in the present study, we devised a method to separate the effect of parenchymal stiffening from that of direct airway narrowing. Six anesthetized dogs were studied under four conditions: baseline, after whole lung aerosol histamine challenge, after local airway histamine challenge, and after complete relaxation of the airways. In each of these conditions, we used High resolution Computed Tomography to measure airway size and lung volume at five different airway pressures (0, 12, 25, 32, and 45 cm H(2O. Parenchymal stiffening had a protective effect on airway narrowing, a fact that may be important in the airway response to deep inspiration in asthma. When the parenchyma was stiffened by whole lung aerosol histamine challenge, at every lung volume above FRC, the airways were larger than when they were directly challenged with histamine to the same initial constriction. These results show for the first time that a stiff parenchyma per se minimizes the airway narrowing that occurs with histamine challenge at any lung volume. Thus in clinical asthma, it is not simply increased airway smooth muscle contraction, but perhaps a lack of homogeneous parenchymal stiffening that contributes to the symptomatic airway hyperresponsiveness.

  17. The influence of upper airways diameter on the intensity of obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Jolanta Szymańska

    2014-03-01

    Full Text Available Introduction and Objective. Obstructive sleep apnea (OSA is characterized by at least 5 ten-second-long episodes of apnea or hypopnea, per hour of sleep. This disease may lead to severe, life-threatening complications. Therefore, risk analysis and its influence on disease intensity is crucial for proper implementation of preventive treatments. Objective. To determine the relation between the intensity of OSA expressed in Apnea-Hypopnea Index (AHI, and the anterior-posterior diameter of upper airways at the levels of soft palate and tongue base. Material and Method. Medical records of 41 patients with sleep apnea (AHI>4 diagnosed through polysomnographic examination obstructive were used for the study. The data consisted of: age and gender, polysomnographic examination results (AHI, lateral cephalogram with cephalomertic analysis, together with measurements of the upper and lower pharyngeal depth according to McNamara. Statistical analysis was carried out in accordance with Pearson’s r correlation coefficient test (Statistica 8.0 software package. Results. Analysis of the influence of upper airways diameter on the intensity of OSA showed that the value of upper Airways diameter at the tongue base level had no statistically significant impact on the value of AHI (p=0.795. However, a statistically significant impact of the value of upper airways diameter on the AHI value (p=0.008 at the soft palate level was observed. Patients with OSA have narrowed upper airways diameter. The value of AHI increases with the decrease of upper diameter and is not dependent on a lower diameter value. Patients with a decreased upper airways diameter should be informed about potential breathing disorders during sleep.

  18. Continuous positive airway pressure reduces blood pressure in patients with obstructive sleep apnea; a systematic review and meta-analysis with 1000 patients.

    Science.gov (United States)

    Schein, Andressa S O; Kerkhoff, Alessandra C; Coronel, Christian C; Plentz, Rodrigo D M; Sbruzzi, Graciele

    2014-09-01

    Obstructive sleep apnea (OSA) may lead to the development of hypertension and therapy with continuous positive airway pressure (CPAP) can promote reduction in blood pressure. The objective of this study is to review systematically the effects of CPAP on blood pressure in patients with OSA. The search was conducted in the following databases, from their beginning until February 2013: MEDLINE, Embase, Cochrane CENTRAL, Lilacs and PEDro. In addition, a manual search was performed on references of published studies. Randomized clinical trials (RCTs) that used CPAP compared with placebo CPAP or subtherapeutic CPAP for treatment of patients with OSA and that evaluated office SBP and DBP and 24-h ambulatory blood pressure were selected. Sixteen RCTs were included among 3409 publications, totaling 1166 patients. The use of CPAP resulted in reductions in office SBP [-3.20  mmHg; 95% confidence interval (CI) -4.67 to -1.72] and DBP (-2.87  mmHg; 95% CI -5.18 to -0.55); in night-time SBP (-4.92  mmHg; 95% CI -8.70 to -1.14); in mean 24-h blood pressure (-3.56  mmHg; 95% CI -6.79 to -0.33), mean night-time blood pressure (-2.56  mmHg; 95% CI -4.43 to -0.68) and 24-h DBP (-3.46  mmHg; 95% CI -6.75 to -0.17). However, no significant change was observed in daytime SBP (-0.74  mmHg; 95% CI -3.90 to 2.41) and daytime DBP (-1.86  mmHg; 95% CI -4.55 to 0.83). Treatment with CPAP promoted significantly but small reductions in blood pressure in individuals with OSA. Further studies should be performed to evaluate the effects of long-term CPAP and the impact on cardiovascular risk.

  19. Positive pressure ventilation in the management of acute and chronic cardiac failure: a systematic review and meta-analysis.

    Science.gov (United States)

    Nadar, Sunil; Prasad, Neeraj; Taylor, Rod S; Lip, Gregory Y H

    2005-03-18

    Chronic heart failure (CHF) is a common condition and is associated with excess morbidity and mortality, in spite of the many advances in its treatment. Chronic stable heart failure is also associated with an increased incidence of sleep-related breathing disorders, such as central sleep apnoea (CSA) and Cheyne Stokes respiration (CSR). Continuous positive airways pressure (CPAP) has been shown to alleviate the symptoms of CHF, improve left ventricular function and oxygenation. To a certain extent, CPAP also abolishes sleep-related breathing disorders in patients with chronic heart failure. In patients with acute pulmonary oedema, the use of positive pressure ventilation improves cardiac haemodynamic indices, as well as symptoms and oxygenation, and is associated with a lower need for intubation. However, some studies have cast doubts about its safety and suggest a higher rate of myocardial infarction associated with its use. In our opinion, non-invasive positive pressure ventilation and CPAP offers an adjunctive mode of therapy in patients with acute pulmonary oedema and chronic heart failure, who may not be suitable for intubation and in those not responsive to conventional therapies. Non-invasive ventilation also helps to improve oxygenation in those patients with exhaustion and respiratory acidosis. Many trials are still ongoing and the results of these studies would throw more light on the present role of non-invasive ventilation in the management of CHF.

  20. Airway distensibility in Chronic Obstructive Airway Disease

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Pedersen, Jesper Holst; Dirksen, Asger

    2013-01-01

    Rationale – Chronic Obstructive Pulmonary Disease (COPD) is a combination of chronic bronchitis and emphysema, which both may lead to airway obstruction. Under normal circumstances, airway dimensions vary as a function of inspiration level. We aim to study the influence of COPD and emphysema......-20% (mild), 20%-30% (moderate) or >30% (severe). Spirometry was performed annually and participants were divided into severity groups according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Data were analysed in a mixed effects regression model with log(airway lumen diameter...... and emphysema, respectively. Conclusions – Airway distensibility decreases significantly with increasing severity of both GOLD status and emphysema, indicating that in COPD the dynamic change in airway calibre during respiration is compromised. Chronic bronchitis and emphysema appear to be interacting...

  1. Comparison of quiet breathing and controlled ventilation in the high-resolution CT assessment of airway disease in infants with cystic fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Long, Frederick R.; Adler, Brent H. [Children' s Radiological Institute, Children' s Hospital, Columbus, OH (United States); Williams, Roger S. [Christiana Hospitals, Department of Radiology, Newark, DE (United States); Castile, Robert G. [Children' s Hospital, Section of Pulmonary Medicine, Department of Pediatrics, Columbus, OH (United States)

    2005-11-01

    Respiratory motion and low lung volumes limit the quality of HRCT examinations in infants and young children. To assess the effects of respiratory motion and lung inflation on the ability to diagnose airway abnormalities and air trapping (AT) using HRCT in infants with cystic fibrosis (CF). HRCT images of the lungs were obtained at four anatomical levels in 16 sedated children (age 2.4{+-}1.1 years, mean{+-}SD) with CF using controlled ventilation at full lung inflation (CVCT-I), at resting end exhalation (CVCT-E), and during quiet breathing (CT-B). Two blinded reviewers independently and then by consensus scored all images for the presence or absence of bronchiectasis (BE), bronchial wall thickening (BWT), and AT. Of the 64 images evaluated, BE was identified in 19 (30%) of the CVCT-I images compared to 6 (9%) of the CVCT-E images (P=0.006) and 4 (6%) of the CT-B images (P=0.044). AT was seen in 29 (45%) of the CVCT-E images compared to 14 (22%) of the CVCT-I images (P=0.012) and 12 (19%) of the CT-B images (P=0.012). There were no significant differences in the detection of BWT among the three methods. Summary: In infants with CF, fully inflating the lung improved the ability to diagnose early BE, and obtaining motion-free images at end exhalation enhanced the detection of AT. (orig.)

  2. Therapeutical options for the treatment of Cheyne-Stokes respiration.

    Science.gov (United States)

    Randerath, Winfried J

    2009-03-07

    The awareness of Cheyne-Stokes respiration (CSR) and of the co-existence of the obstructive sleep apnoea syndrome and central breathing disturbances has rapidly grown in recent years. CSR is defined by a waxing and waning pattern of the breathing amplitude. Sleep related breathing disorders in patients with heart failure are associated with impaired clinical outcome and survival. While continuous positive airway pressure treatment (CPAP) is widely used to treat CSR, it has failed to improve overall survival of heart failure patients. Nevertheless, it has been shown that CPAP reduces mortality if breathing disturbances were sufficiently eliminated. Therefore, optimal suppression of CSR is critical. While CPAP reduces CSR by 50% on average, adaptive servoventilation (ASV) normalises CSR in most patients. ASV devices apply different levels of pressure support: during periods of hypoventilation the inspiratory pressure is increased while it is reduced to the lowest possible level during hyperventilation. The devices deliver an expiratory pressure to overcome upper airways obstruction. Pressure support is defined by the difference between expiratory and inspiratory pressure. Thus, while pressure support is fixed in bilevel devices, it varies under ASV. However, the hypothesis that ASV might improve survival in CSR patients has to be proved in prospective studies in CPAP nonresponders. There is a lack of evidence on the use of bilevel devices in CSR. However, ASV has proven both to effectively treat CSR and to be superior to CPAP in respiratory and sleep parameters in short term and medium term studies. Nevertheless, data on the long term use and the influence on cardiac parameters are necessary.

  3. Breathing adapted radiotherapy for breast cancer: comparison of free breathing gating with the breath-hold technique

    DEFF Research Database (Denmark)

    Korreman, Stine Sofia; Pedersen, Anders N; Nøttrup, Trine Jakobi

    2005-01-01

    BACKGROUND AND PURPOSE: Adjuvant radiotherapy after breast-conserving surgery for breast cancer implies a risk of late cardiac and pulmonary toxicity. This is the first study to evaluate cardiopulmonary dose sparing of breathing adapted radiotherapy (BART) using free breathing gating......, and to compare this respiratory technique with voluntary breath-hold. PATIENTS AND METHODS: 17 patients were CT-scanned during non-coached breathing manoeuvre including free breathing (FB), end-inspiration gating (IG), end-expiration gating (EG), deep inspiration breath-hold (DIBH) and end-expiration breath......-hold (EBH). The Varian Real-time Position Management system (RPM) was used to monitor respiratory movement and to gate the scanner. For each breathing phase, a population based internal margin (IM) was estimated based on average chest wall excursion, and incorporated into an individually optimised three...

  4. The role of telemedicine and mobile health in the monitoring of sleep-breathing disorders: improving patient outcomes

    Directory of Open Access Journals (Sweden)

    Villanueva JA

    2017-02-01

    Full Text Available Jair A Villanueva,1,* Monique C Suarez,2,* Onintza Garmendia,2,3 Vera Lugo,2 Concepción Ruiz,2 Josep M Montserrat,2–5 1Unit of Biophysics and Bioengineering, Faculty of Medicine, University of Barcelona, 2Sleep Unit, Respiratory Medicine Department, Hospital Clinic, Barcelona, 3Center for Biomedical Research in Respiratory Diseases (CIBERES, Madrid, 4Faculty of Medicine, University of Barcelona, 5August Pi i Sunyer Biomedical Research Institute (IDIBAPS, Barcelona, Spain *These authors contributed equally to this work Abstract: Although the concepts are broad, telemedicine and mobile health (mHealth can be defined as a methodology to provide health care remotely and improve health services and outcomes using telecommunication tools. The widespread adoption of these technologies and current health care challenges, such as the aging population and increasing costs, has encouraged interest in the development of new strategies involving telemedicine. Overall, there is a lack of evidence rigorously assessing the impact of telemedicine and mHealth. Therefore, proper randomized controlled trials, with cost-effectiveness and impact on quality-of-life analysis, are urgently needed. They should also focus on specific populations and their comorbidities, since customizing telemedicine approaches is paramount to ensure success. Obstructive sleep apnea is a highly prevalent chronic condition and the most common of sleep-breathing disorders, and telemedicine and mHealth could play a pivotal role in the different phases of its management. In the future, using new devices capable of signal acquisition and analysis will refine obstructive sleep apnea diagnosis; even smartphones’ built-in sensors could offer improved comfort and the possibility of home sleep monitoring. Continuous positive airway pressure titration could be performed with wireless devices, whose parameters can be changed remotely from sleep centers. Finally, the follow-up phase could be

  5. Investigation of airways using MDCT for visual and quantitative assessment in COPD patients

    Directory of Open Access Journals (Sweden)

    Pierre-Yves Brillet

    2008-03-01

    Full Text Available Pierre-Yves Brillet1, Catalin I Fetita2, Amaury Saragaglia2, Anne-Laure Brun3, Catherine Beigelman-Aubry3, Françoise Prêteux2, Philippe A Grenier31Department of Radiology, Avicenne Hospital, Assistance Publique–Hôpitaux de Paris, Université Léonard de Vinci–Paris Nord, EA 2361, Bobigny, France; 2ARTEMIS Department, Institut National des Télécommunications, Université Paris V, Evry, France; 3Department of Radiology, Pitié-Salpêtrière Hospital, Assistance Publique–Hôpitaux de Paris, Université Pierre et Marie Curie, Paris, FranceAbstract: Multidetector computed tomography (MDCT acquisition during a single breath hold using thin collimation provides high resolution volumetric data set permitting multiplanar and three dimensional reconstruction of the proximal airways. In chronic obstructive pulmonary disease (COPD patients, this technique provides an accurate assessment of bronchial wall thickening, tracheobronchial deformation, outpouchings reflecting dilatation of the submucous glands, tracheobronchomalacia, and expiratory air trapping. New software developed to segment adequately the lumen and walls of the airways on MDCT scans allows quantitative assessment of the airway dimensions which has shown to be reliable in clinical practice. This technique can become important in longitudinal studies of the pathogenesis of COPD, and in the assessment of therapeutic interventions.Keywords: COPD – tracheobronchial tree, multidetector CT – airway remodeling, tracheobronchomalacia

  6. Comparison of HFNC, bubble CPAP and SiPAP on aerosol delivery in neonates: An in-vitro study.

    Science.gov (United States)

    Sunbul, Fatemah S; Fink, James B; Harwood, Robert; Sheard, Meryl M; Zimmerman, Ralph D; Ari, Arzu

    2015-11-01

    Aerosol drug delivery via high flow nasal cannula (HFNC), bubble continuous positive airway pressure (CPAP), and synchronized inspiratory positive airway pressure (SiPAP) has not been quantified in spontaneously breathing premature infants. The purpose of this study was to compare aerosol delivery via HFNC, bubble CPAP, and SiPAP in a model of a simulated spontaneously breathing preterm infant. The types of CPAP systems and nebulizer positions used during aerosol therapy will impact aerosol deposition in simulated spontaneously breathing infants. Quantitative, comparative, in-vitro study. A breath simulator was set to preterm infant settings (VT : 9 ml, RR: 50 bpm and Ti: 0.5 sec) and connected to the trachea of an anatomical upper airway model of a preterm infant via collecting filter distal to the trachea. The HFNC (Optiflow; Fisher & Paykel), Bubble CPAP (Fisher & Paykel), and SiPAP (Carefusion) were attached to the nares of the model via each device's proprietary nasal cannula and set to deliver a baseline of 5 cm H2 O pressure. Albuterol sulfate (2.5 mg/0.5 ml) was aerosolized with a mesh nebulizer (Aeroneb Solo) positioned(1) proximal to the patient and(2) prior to the humidifier (n = 5). The drug was eluted from the filter with 0.1 N HCl and analyzed via spectrophotometry (276 nm). Data were analyzed using descriptive statistics, t-tests, and one-way analysis of variance (ANOVA), with P CPAP (1.24 ± 0.24; p = 0.008). Placement of the nebulizer prior to the humidifier increased deposition with all devices (P < 0.05). Aerosol can be delivered via all three devices used in this study. Device selection and nebulizer position impacted aerosol delivery in this simulated model of a spontaneously breathing preterm infant. © 2014 Wiley Periodicals, Inc.

  7. Is the Relationship between Race and Continuous Positive Airway Pressure Adherence Mediated by Sleep Duration?

    Science.gov (United States)

    Billings, Martha E.; Rosen, Carol L.; Wang, Rui; Auckley, Dennis; Benca, Ruth; Foldvary-Schaefer, Nancy; Iber, Conrad; Zee, Phyllis; Redline, Susan; Kapur, Vishesh K.

    2013-01-01

    Study Objectives: Black race has been associated with decreased continuous positive airway pressure (CPAP) adherence. Short sleep duration, long sleep latency, and insomnia complaints may affect CPAP adherence as they affect sleep and opportunity to use CPAP. We assessed whether self-reported sleep measures were associated with CPAP adherence and if racial variations in these sleep characteristics may explain racial differences in CPAP adherence. Design: Analysis of data from a randomized controlled trial (HomePAP), which investigated home versus laboratory-based diagnosis and treatment of obstructive sleep apnea. Setting: Seven American Academy of Sleep Medicine-accredited sleep centers in five cities in the United States. Patients or Participants: Enrolled subjects (n = 191) with apnea-hypopnea index ≥ 15 and sleepiness (Epworth Sleepiness Scale > 12). Interventions: N/A. Measurements and Results: Multivariable regression was used to assess if subjective sleep measures and symptoms predicted 3-mo CPAP use. Mediation analysis was used to assess if sleep measures mediated the association of race with CPAP adherence. Black participants reported shorter sleep duration and longer sleep latency at baseline than white and Hispanic participants. Shorter sleep duration and longer sleep latency predicted worse CPAP adherence. Sleep duration mediated the association of black race with lower CPAP adherence. However, insomnia symptoms were not associated with race or CPAP adherence. Conclusions: Among subjects with similar severity of obstructive sleep apnea and sleepiness, baseline self-reported sleep duration and latency, but not perceived insomnia, predicted CPAP adherence over 3 mo. Sleep duration explains some of the observed differences in CPAP use by race. Sleep duration and latency should be considered when evaluating poor CPAP adherence. Clinical Trial Information: Portable Monitoring for Diagnosis and Management of Sleep Apnea (HomePAP) URL: http

  8. Effect of Continuous Positive Airway Pressure on Stroke Rehabilitation: A Pilot Randomized Sham-Controlled Trial

    Science.gov (United States)

    Khot, Sandeep P.; Davis, Arielle P.; Crane, Deborah A.; Tanzi, Patricia M.; Li Lue, Denise; Claflin, Edward S.; Becker, Kyra J.; Longstreth, W.T.; Watson, Nathaniel F.; Billings, Martha E.

    2016-01-01

    Study Objectives: Obstructive sleep apnea (OSA) predicts poor functional outcome after stroke and increases the risk for recurrent stroke. Less is known about continuous positive airway pressure (CPAP) treatment on stroke recovery. Methods: In a pilot randomized, double-blind, sham-controlled trial, adult stroke rehabilitation patients were assigned to auto-titrating or sham CPAP without diagnostic testing for OSA. Change in Functional Independence Measure (FIM), a measure of disability, was assessed between rehabilitation admission and discharge. Results: Over 18 months, 40 patients were enrolled and 10 withdrew from the study: 7 from active and 3 from sham CPAP (p > 0.10). For the remaining 30 patients, median duration of CPAP use was 14 days. Average CPAP use was 3.7 h/night, with at least 4 h nightly use among 15 patients. Adherence was not influenced by treatment assignment or stroke severity. In intention-to-treat analyses (n = 40), the median change in FIM favored active CPAP over sham but did not reach statistical significance (34 versus 26, p = 0.25), except for the cognitive component (6 versus 2.5, p = 0.04). The on-treatment analyses (n = 30) yielded similar results (total FIM: 32 versus 26, p = 0.11; cognitive FIM: 6 versus 2, p = 0.06). Conclusions: A sham-controlled CPAP trial among stroke rehabilitation patients was feasible in terms of recruitment, treatment without diagnostic testing and adequate blinding—though was limited by study retention and CPAP adherence. Despite these limitations, a trend towards a benefit of CPAP on recovery was evident. Tolerance and adherence must be improved before the full benefits of CPAP on recovery can be assessed in larger trials. Citation: Khot SP, Davis AP, Crane DA, Tanzi PM, Li Lue D, Claflin ES, Becker KJ, Longstreth WT, Watson NF, Billings ME. Effect of continuous positive airway pressure on stroke rehabilitation: a pilot randomized sham-controlled trial. J Clin Sleep Med 2016;12(7):1019–1026. PMID

  9. Influence of Very High Breathing Resistance on Exercise Tolerance, Part 1 - Dry Exercise

    Science.gov (United States)

    2016-01-01

    endurance times. 15. SUBJECT TERMS control of breathing, ventilation, CO2, carbon dioxide, hypercapnia, CO2 retention , dyspnea, exercise, performance...to be near his exercise capacity , until the subject could no longer continue. Subjects were asked to give scores of Relative Perceived Exertion (RPE...span gas (5% CO2 and 16% O2 in nitrogen). The pressure transducer outputs were compared to a water manometer. Data analysis Breath by breath

  10. Delivery room continuous positive airway pressure and early pneumothorax in term newborn infants.

    Science.gov (United States)

    Clevenger, L; Britton, J R

    2017-01-01

    To assess the association between delivery room (DR) continuous positive airway pressure (CPAP) and pneumothorax (PT) in term newborns. Two studies performed in community hospitals used data extracted from computerized records of term newborns. Infants receiving positive pressure ventilation in the DR were excluded. Tabulated data included receipt of DR CPAP, PT on the day of birth, and gestational age (GA). In a case-control study from 2001-2013, infants with PT were compared to controls without PT but with respiratory distress or hypoxia persisting from birth for receipt of DR CPAP. In a cohort study from 2014-2016, infants receiving and not receiving DR CPAP were compared for the incidence of PT. In the case-control study, data were obtained for 169 cases and 850 controls. Compared to controls, PT infants were more likely to have received DR CPAP (16.8% vs. 40.2%, respectively, P CPAP (Adjusted Odds Ratio [AOR] = 3.30, 95% confidence interval [CI] = 2.31, 4.72, P CPAP and 4.8% of 228 infants receiving DR CPAP (P CPAP significantly predicted PT (OR = 59.59, 95% CI = 23.34, 147.12, P CPAP in delivery rooms are associated with increased risk of PT. A cause-and-effect relationship between CPAP and PT cannot be claimed in this study. Further research is needed to better understand this relationship.

  11. Continuous positive airway pressure and conventional mechanical ventilation in the treatment of meconium aspiration syndrome.

    Science.gov (United States)

    Goldsmith, J P

    2008-12-01

    Meconium aspiration syndrome (MAS) is a complex syndrome that ranges in severity from mild respiratory distress to severe respiratory failure, persistent pulmonary hypertension of the newborn and sometimes death. Understanding of the syndrome's complicated pathophysiology will help determine the appropriate treatment strategy, including the use of continuous positive airway pressure (CPAP), conventional mechanical ventilation (CMV) and other therapies. Approximately 30 to 50% of infants diagnosed with MAS will require CPAP or mechanical ventilation. The optimum modes of ventilation for MAS are not known. Very few studies have been conducted to determine 'best' ventilatory strategies. Despite the introduction, over the last two decades, of innovative ventilatory treatments for this disease (for example, surfactant, high-frequency ventilation, inhaled nitric oxide, extracorporeal membrane oxygenation), the majority of infants can be successfully managed with CPAP or mechanical ventilation alone.

  12. Cardiovascular risk in patients with sleep apnoea with or without continuous positive airway pressure therapy

    DEFF Research Database (Denmark)

    Lamberts, Morten; Nielsen, O W; Lip, G Y H

    2014-01-01

    BACKGROUND: The prognostic significance of age and continuous positive airway pressure (CPAP) therapy on cardiovascular disease in patients with sleep apnoea has not been assessed previously. METHODS: Using nationwide databases, the entire Danish population was followed from 2000 until 2011. First......-time sleep apnoea diagnoses and use of CPAP therapy were determined. Incidence rate ratios (IRRs) of ischaemic stroke and myocardial infarction (MI) were analysed using Poisson regression models. RESULTS: Amongst 4.5 million individuals included in the study, 33 274 developed sleep apnoea (mean age 53, 79......% men) of whom 44% received persistent CPAP therapy. Median time to initiation of CPAP therapy was 88 days (interquartile range 34-346). Patients with sleep apnoea had more comorbidities compared to the general population. Crude rates of MI and ischaemic stroke were increased for sleep apnoea patients...

  13. Double blind randomised controlled trial of two different breathing techniques in the management of asthma

    Science.gov (United States)

    Slader, C A; Reddel, H K; Spencer, L M; Belousova, E G; Armour, C L; Bosnic‐Anticevich, S Z; Thien, F C K; Jenkins, C R

    2006-01-01

    Background Previous studies have shown that breathing techniques reduce short acting β2 agonist use and improve quality of life (QoL) in asthma. The primary aim of this double blind study was to compare the effects of breathing exercises focusing on shallow nasal breathing with those of non‐specific upper body exercises on asthma symptoms, QoL, other measures of disease control, and inhaled corticosteroid (ICS) dose. This study also assessed the effect of peak flow monitoring on outcomes in patients using breathing techniques. Methods After a 2 week run in period, 57 subjects were randomised to one of two breathing techniques learned from instructional videos. During the following 30 weeks subjects practised their exercises twice daily and as needed for relief of symptoms. After week 16, two successive ICS downtitration steps were attempted. The primary outcome variables were QoL score and daily symptom score at week 12. Results Overall there were no clinically important differences between the groups in primary or secondary outcomes at weeks 12 or 28. The QoL score remained unchanged (0.7 at baseline v 0.5 at week 28, p = 0.11 both groups combined), as did lung function and airway responsiveness. However, across both groups, reliever use decreased by 86% (p0.10 between groups). Peak flow monitoring did not have a detrimental effect on asthma outcomes. Conclusion Breathing techniques may be useful in the management of patients with mild asthma symptoms who use a reliever frequently, but there is no evidence to favour shallow nasal breathing over non‐specific upper body exercises. PMID:16517572

  14. Nasal continuous positive airway pressure treatment: current realities and future.

    Science.gov (United States)

    Berthon-Jones, M; Lawrence, S; Sullivan, C E; Grunstein, R

    1996-11-01

    Nasal continuous positive airway pressure (CPAP) is a highly effective treatment for obstructive sleep apnea syndrome. The apnea/hypopnea index (AHI) is reduced 10-fold, but the patient dropout rate is up to 30%, and usage is typically 20/hour were recruited, with written informed consent. Subjects slept for a diagnostic night, followed by a treatment night, in the laboratory, using the AutoSet system with full polysomnographic monitoring of respiratory and sleep variables. Arousals were scored using ASDA criteria. Hypopneas were scored when there was a 50% reduction in ventilation for > 10 seconds, associated with a 4% drop in oxygen saturation. For comparison, the ASDA arousal index in 16 normal subjects (without nasal CPAP) is provided. Results are given as mean +/- standard error of the mean. AHI was reduced from 55 +/- 3 to 1.5 +/- 0.35 events/hour (p < 0.0001). The arousal index was reduced from 65 +/- 3 to 18 +/- 2 events/hour (p < 0.0001), identical to the value in the 16 healthy normal subjects. There was a 158% +/- 21% increase in slow-wave sleep (p = 0.01) and a 186% +/- 27% increase in rapid eye movement sleep (p = 0.013). The AutoSet self-adjusting nasal CPAP system adequately treats obstructive sleep apnea syndrome on the first night under laboratory conditions.

  15. Using the Electronic Nose to Identify Airway Infection during COPD Exacerbations.

    Directory of Open Access Journals (Sweden)

    Hanaa Shafiek

    Full Text Available The electronic nose (e-nose detects volatile organic compounds (VOCs in exhaled air. We hypothesized that the exhaled VOCs print is different in stable vs. exacerbated patients with chronic obstructive pulmonary disease (COPD, particularly if the latter is associated with airway bacterial infection, and that the e-nose can distinguish them.Smell-prints of the bacteria most commonly involved in exacerbations of COPD (ECOPD were identified in vitro. Subsequently, we tested our hypothesis in 93 patients with ECOPD, 19 of them with pneumonia, 50 with stable COPD and 30 healthy controls in a cross-sectional case-controlled study. Secondly, ECOPD patients were re-studied after 2 months if clinically stable. Exhaled air was collected within a Tedlar bag and processed by a Cynarose 320 e-nose. Breath-prints were analyzed by Linear Discriminant Analysis (LDA with "One Out" technique and Sensor logic Relations (SLR. Sputum samples were collected for culture.ECOPD with evidence of infection were significantly distinguishable from non-infected ECOPD (p = 0.018, with better accuracy when ECOPD was associated to pneumonia. The same patients with ECOPD were significantly distinguishable from stable COPD during follow-up (p = 0.018, unless the patient was colonized. Additionally, breath-prints from COPD patients were significantly distinguished from healthy controls. Various bacteria species were identified in culture but the e-nose was unable to identify accurately the bacteria smell-print in infected patients.E-nose can identify ECOPD, especially if associated with airway bacterial infection or pneumonia.

  16. Coordinated Respiratory Motor Activity in Nerves Innervating the Upper Airway Muscles in Rats.

    Directory of Open Access Journals (Sweden)

    Satoshi Tachikawa

    Full Text Available Maintaining the patency of the upper airway during breathing is of vital importance. The activity of various muscles is related to the patency of the upper airway. In the present study, we examined the respiratory motor activity in the efferent nerves innervating the upper airway muscles to determine the movements of the upper airway during respiration under normocapnic conditions (pH = 7.4 and in hypercapnic acidosis (pH = 7.2. Experiments were performed on arterially perfused decerebrate rats aged between postnatal days 21-35. We recorded the efferent nerve activity in a branch of the cervical spinal nerve innervating the infrahyoid muscles (CN, the hypoglossal nerve (HGN, the external branch of the superior laryngeal nerve (SLN, and the recurrent laryngeal nerve (RLN with the phrenic nerve (PN. Inspiratory nerve discharges were observed in all these nerves under normocapnic conditions. The onset of inspiratory discharges in the CN and HGN was slightly prior to those in the SLN and RLN. When the CO2 concentration in the perfusate was increased from 5% to 8% to prepare for hypercapnic acidosis, the peak amplitudes of the inspiratory discharges in all the recorded nerves were increased. Moreover, hypercapnic acidosis induced pre-inspiratory discharges in the CN, HGN, SLN, and RLN. The onset of pre-inspiratory discharges in the CN, HGN, and SLN was prior to that of discharges in the RLN. These results suggest that the securing of the airway that occurs a certain time before dilation of the glottis may facilitate ventilation and improve hypercapnic acidosis.

  17. Integrated care pathways for airway diseases (AIRWAYS-ICPs)

    NARCIS (Netherlands)

    Bousquet, J.; Addis, A.; Adcock, I.; Agache, I.; Agusti, A.; Alonso, A.; Annesi-Maesano, I.; Anto, J. M.; Bachert, C.; Baena-Cagnani, C. E.; Bai, C.; Baigenzhin, A.; Barbara, C.; Barnes, P. J.; Bateman, E. D.; Beck, L.; Bedbrook, A.; Bel, E. H.; Benezet, O.; Bennoor, K. S.; Benson, M.; Bernabeu-Wittel, M.; Bewick, M.; Bindslev-Jensen, C.; Blain, H.; Blasi, F.; Bonini, M.; Bonini, S.; Boulet, L. P.; Bourdin, A.; Bourret, R.; Bousquet, P. J.; Brightling, C. E.; Briggs, A.; Brozek, J.; Buhl, R.; Bush, A.; Caimmi, D.; Calderon, M.; Calverley, P.; Camargos, P. A.; Camuzat, T.; Canonica, G. W.; Carlsen, K. H.; Casale, T. B.; Cazzola, M.; Cepeda Sarabia, A. M.; Cesario, A.; Chen, Y. Z.; Chkhartishvili, E.; Chavannes, N. H.; Chiron, R.; Chuchalin, A.; Chung, K. F.; Cox, L.; Crooks, G.; Crooks, M. G.; Cruz, A. A.; Custovic, A.; Dahl, R.; Dahlen, S. E.; de Blay, F.; Dedeu, T.; Deleanu, D.; Demoly, P.; Devillier, P.; Didier, A.; Dinh-Xuan, A. T.; Djukanovic, R.; Dokic, D.; Douagui, H.; Dubakiene, R.; Eglin, S.; Elliot, F.; Emuzyte, R.; Fabbri, L.; Fink Wagner, A.; Fletcher, M.; Fokkens, W. J.; Fonseca, J.; Franco, A.; Frith, P.; Furber, A.; Gaga, M.; Garcés, J.; Garcia-Aymerich, J.; Gamkrelidze, A.; Gonzales-Diaz, S.; Gouzi, F.; Guzmán, M. A.; Haahtela, T.; Harrison, D.; Hayot, M.; Heaney, L. G.; Heinrich, J.; Hellings, P. W.; Hooper, J.; Humbert, M.; Hyland, M.; Iaccarino, G.; Jakovenko, D.; Jardim, J. R.; Jeandel, C.; Jenkins, C.; Johnston, S. L.; Jonquet, O.; Joos, G.; Jung, K. S.; Kalayci, O.; Karunanithi, S.; Keil, T.; Khaltaev, N.; Kolek, V.; Kowalski, M. L.; Kull, I.; Kuna, P.; Kvedariene, V.; Le, L. T.; Lodrup Carlsen, K. C.; Louis, R.; MacNee, W.; Mair, A.; Majer, I.; Manning, P.; de Manuel Keenoy, E.; Masjedi, M. R.; Melen, E.; Melo-Gomes, E.; Menzies-Gow, A.; Mercier, G.; Mercier, J.; Michel, J. P.; Miculinic, N.; Mihaltan, F.; Milenkovic, B.; Molimard, M.; Momas, I.; Montilla-Santana, A.; Morais-Almeida, M.; Morgan, M.; N'Diaye, M.; Nafti, S.; Nekam, K.; Neou, A.; Nicod, L.; O'Hehir, R.; Ohta, K.; Paggiaro, P.; Palkonen, S.; Palmer, S.; Papadopoulos, N. G.; Papi, A.; Passalacqua, G.; Pavord, I.; Pigearias, B.; Plavec, D.; Postma, D. S.; Price, D.; Rabe, K. F.; Radier Pontal, F.; Redon, J.; Rennard, S.; Roberts, J.; Robine, J. M.; Roca, J.; Roche, N.; Rodenas, F.; Roggeri, A.; Rolland, C.; Rosado-Pinto, J.; Ryan, D.; Samolinski, B.; Sanchez-Borges, M.; Schünemann, H. J.; Sheikh, A.; Shields, M.; Siafakas, N.; Sibille, Y.; Similowski, T.; Small, I.; Sola-Morales, O.; Sooronbaev, T.; Stelmach, R.; Sterk, P. J.; Stiris, T.; Sud, P.; Tellier, V.; To, T.; Todo-Bom, A.; Triggiani, M.; Valenta, R.; Valero, A. L.; Valiulis, A.; Valovirta, E.; van Ganse, E.; Vandenplas, O.; Vasankari, T.; Vestbo, J.; Vezzani, G.; Viegi, G.; Visier, L.; Vogelmeier, C.; Vontetsianos, T.; Wagstaff, R.; Wahn, U.; Wallaert, B.; Whalley, B.; Wickman, M.; Williams, D. M.; Wilson, N.; Yawn, B. P.; Yiallouros, P. K.; Yorgancioglu, A.; Yusuf, O. M.; Zar, H. J.; Zhong, N.; Zidarn, M.; Zuberbier, T.

    2014-01-01

    The objective of Integrated Care Pathways for Airway Diseases (AIRWAYS-ICPs) is to launch a collaboration to develop multi-sectoral care pathways for chronic respiratory diseases in European countries and regions. AIRWAYS-ICPs has strategic relevance to the European Union Health Strategy and will

  18. Integrated care pathways for airway diseases (AIRWAYS-ICPs)

    NARCIS (Netherlands)

    Bousquet, J.; Addis, A.; Adcock, I.; Agache, I.; Agusti, A.; Alonso, A.; Annesi-Maesano, I.; Anto, J. M.; Bachert, C.; Baena-Cagnani, C. E.; Bai, C.; Baigenzhin, A.; Barbara, C.; Barnes, P. J.; Bateman, E. D.; Beck, L.; Bedbrook, A.; Bel, E. H.; Benezet, O.; Bennoor, K. S.; Benson, M.; Bernabeu-Wittel, M.; Bewick, M.; Bindslev-Jensen, C.; Blain, H.; Blasi, F.; Bonini, M.; Bonini, S.; Boulet, L. P.; Bourdin, A.; Bourret, R.; Bousquet, P. J.; Brightling, C. E.; Briggs, A.; Brozek, J.; Buh, R.; Bush, A.; Caimmi, D.; Calderon, M.; Calverley, P.; Camargos, P. A.; Camuzat, T.; Canonica, G. W.; Carlsen, K. H.; Casale, T. B.; Cazzola, M.; Sarabia, A. M. Cepeda; Cesario, A.; Chen, Y. Z.; Chkhartishvili, E.; Chavannes, N. H.; Chiron, R.; Chuchalin, A.; Chung, K. F.; Cox, L.; Crooks, G.; Crooks, M. G.; Cruz, A. A.; Custovic, A.; Dahl, R.; Dahlen, S. E.; De Blay, F.; Dedeu, T.; Deleanu, D.; Demoly, P.; Devillier, P.; Didier, A.; Dinh-Xuan, A. T.; Djukanovic, R.; Dokic, D.; Douagui, H.; Dubakiene, R.; Eglin, S.; Elliot, F.; Emuzyte, R.; Fabbri, L.; Wagner, A. Fink; Fletcher, M.; Fokkens, W. J.; Fonseca, J.; Franco, A.; Frith, P.; Furber, A.; Gaga, M.; Garces, J.; Garcia-Aymerich, J.; Gamkrelidze, A.; Gonzales-Diaz, S.; Gouzi, F.; Guzman, M. A.; Haahtela, T.; Harrison, D.; Hayot, M.; Heaney, L. G.; Heinrich, J.; Hellings, P. W.; Hooper, J.; Humbert, M.; Hyland, M.; Iaccarino, G.; Jakovenko, D.; Jardim, J. R.; Jeandel, C.; Jenkins, C.; Johnston, S. L.; Jonquet, O.; Joos, G.; Jung, K. S.; Kalayci, O.; Karunanithi, S.; Keil, T.; Khaltaev, N.; Kolek, V.; Kowalski, M. L.; Kull, I.; Kuna, P.; Kvedariene, V.; Le, L. T.; Carlsen, K. C. Lodrup; Louis, R.; MacNee, W.; Mair, A.; Majer, I.; Manning, P.; Keenoy, E. de Manuel; Masjedi, M. R.; Meten, E.; Melo-Gomes, E.; Menzies-Gow, A.; Mercier, G.; Mercier, J.; Michel, J. P.; Miculinic, N.; Mihaltan, F.; Milenkovic, B.; Molimard, M.; Mamas, I.; Montilla-Santana, A.; Morais-Almeida, M.; Morgan, M.; N'Diaye, M.; Nafti, S.; Nekam, K.; Neou, A.; Nicod, L.; O'Hehir, R.; Ohta, K.; Paggiaro, P.; Palkonen, S.; Palmer, S.; Papadopoulos, N. G.; Papi, A.; Passalacqua, G.; Pavord, I.; Pigearias, B.; Plavec, D.; Postma, D. S.; Price, D.; Rabe, K. F.; Pontal, F. Radier; Redon, J.; Rennard, S.; Roberts, J.; Robine, J. M.; Roca, J.; Roche, N.; Rodenas, F.; Roggeri, A.; Rolland, C.; Rosado-Pinto, J.; Ryan, D.; Samolinski, B.; Sanchez-Borges, M.; Schunemann, H. J.; Sheikh, A.; Shields, M.; Siafakas, N.; Sibille, Y.; Similowski, T.; Small, I.; Sola-Morales, O.; Sooronbaev, T.; Stelmach, R.; Sterk, P. J.; Stiris, T.; Sud, P.; Tellier, V.; To, T.; Todo-Bom, A.; Triggiani, M.; Valenta, R.; Valero, A. L.; Valiulis, A.; Valovirta, E.; Van Ganse, E.; Vandenplas, O.; Vasankari, T.; Vestbo, J.; Vezzani, G.; Viegi, G.; Visier, L.; Vogelmeier, C.; Vontetsianos, T.; Wagstaff, R.; Wahn, U.; Wallaert, B.; Whalley, B.; Wickman, M.; Williams, D. M.; Wilson, N.; Yawn, B. P.; Yiallouros, P. K.; Yorgancioglu, A.; Yusuf, O. M.; Zar, H. J.; Zhong, N.; Zidarn, M.; Zuberbier, T.

    The objective of Integrated Care Pathways for Airway Diseases (AIRWAYS-ICPs) is to launch a collaboration to develop multi-sectoral care pathways for chronic respiratory diseases in European countries and regions. AIRWAYS-ICPs has strategic relevance to the European Union Health Strategy and will

  19. Continuous positive airway pressure breathing increases the spread of sensory blockade after low-thoracic epidural injection of lidocaine.

    NARCIS (Netherlands)

    Visser, W.A.; Gielen, M.J.M.; Giele, J.L.P.

    2006-01-01

    Factors affecting the distribution of sensory blockade after epidural injection of local anesthetics remain incompletely clarified. To evaluate if increasing intrathoracic pressure affects the spread of thoracic epidural anesthesia, we randomized 20 patients who received an epidural catheter at the

  20. The role of high airway pressure and dynamic strain on ventilator-induced lung injury in a heterogeneous acute lung injury model.

    Science.gov (United States)

    Jain, Sumeet V; Kollisch-Singule, Michaela; Satalin, Joshua; Searles, Quinn; Dombert, Luke; Abdel-Razek, Osama; Yepuri, Natesh; Leonard, Antony; Gruessner, Angelika; Andrews, Penny; Fazal, Fabeha; Meng, Qinghe; Wang, Guirong; Gatto, Louis A; Habashi, Nader M; Nieman, Gary F

    2017-12-01

    Acute respiratory distress syndrome causes a heterogeneous lung injury with normal and acutely injured lung tissue in the same lung. Improperly adjusted mechanical ventilation can exacerbate ARDS causing a secondary ventilator-induced lung injury (VILI). We hypothesized that a peak airway pressure of 40 cmH 2 O (static strain) alone would not cause additional injury in either the normal or acutely injured lung tissue unless combined with high tidal volume (dynamic strain). Pigs were anesthetized, and heterogeneous acute lung injury (ALI) was created by Tween instillation via a bronchoscope to both diaphragmatic lung lobes. Tissue in all other lobes was normal. Airway pressure release ventilation was used to precisely regulate time and pressure at both inspiration and expiration. Animals were separated into two groups: (1) over-distension + high dynamic strain (OD + H DS , n = 6) and (2) over-distension + low dynamic strain (OD + L DS , n = 6). OD was caused by setting the inspiratory pressure at 40 cmH 2 O and dynamic strain was modified by changing the expiratory duration, which varied the tidal volume. Animals were ventilated for 6 h recording hemodynamics, lung function, and inflammatory mediators followed by an extensive necropsy. In normal tissue (N T ), OD + L DS caused minimal histologic damage and a significant reduction in BALF total protein (p < 0.05) and MMP-9 activity (p < 0.05), as compared with OD + H DS . In acutely injured tissue (ALI T ), OD + L DS resulted in reduced histologic injury and pulmonary edema (p < 0.05), as compared with OD + H DS . Both N T and ALI T are resistant to VILI caused by OD alone, but when combined with a H DS , significant tissue injury develops.

  1. Evaluation of a new pediatric positive airway pressure mask.

    Science.gov (United States)

    Kushida, Clete A; Halbower, Ann C; Kryger, Meir H; Pelayo, Rafael; Assalone, Valerie; Cardell, Chia-Yu; Huston, Stephanie; Willes, Leslee; Wimms, Alison J; Mendoza, June

    2014-09-15

    The choice and variety of pediatric masks for continuous positive airway pressure (CPAP) is limited in the US. Therefore, clinicians often prescribe modified adult masks. Until recently a mask for children aged mask for children aged 2-7 years (Pixi; ResMed Ltd, Sydney, Australia). Patients aged 2-7 years were enrolled and underwent in-lab baseline polysomnography (PSG) using their previous mask, then used their previous mask and the VPAP III ST-A flow generator for ≥ 10 nights at home. Thereafter, patients switched to the Pixi mask for ≥ 2 nights before returning for a PSG during PAP therapy via the Pixi mask. Patients then used the Pixi mask at home for ≥ 21 nights. Patients and their parents/guardians returned to the clinic for follow-up and provided feedback on the Pixi mask versus their previous mask. AHI with the Pixi mask was 1.1 ± 1.5/h vs 2.6 ± 5.4/h with the previous mask (p = 0.3538). Parents rated the Pixi mask positively for: restfulness of the child's sleep, trouble in getting the child to sleep, and trouble in having the child stay asleep. The Pixi mask was also rated highly for leaving fewer or no marks on the upper lip and under the child's ears, and being easy to remove. The Pixi mask is suitable for children aged 2-7 years and provides an alternative to other masks available for PAP therapy in this age group. © 2014 American Academy of Sleep Medicine.

  2. A Patient-Specific Airway Branching Model for Mechanically Ventilated Patients

    Directory of Open Access Journals (Sweden)

    Nor Salwa Damanhuri

    2014-01-01

    Full Text Available Background. Respiratory mechanics models have the potential to guide mechanical ventilation. Airway branching models (ABMs were developed from classical fluid mechanics models but do not provide accurate models of in vivo behaviour. Hence, the ABM was improved to include patient-specific parameters and better model observed behaviour (ABMps. Methods. The airway pressure drop of the ABMps was compared with the well-accepted dynostatic algorithm (DSA in patients diagnosed with acute respiratory distress syndrome (ARDS. A scaling factor (α was used to equate the area under the pressure curve (AUC from the ABMps to the AUC of the DSA and was linked to patient state. Results. The ABMps recorded a median α value of 0.58 (IQR: 0.54–0.63; range: 0.45–0.66 for these ARDS patients. Significantly lower α values were found for individuals with chronic obstructive pulmonary disease (P<0.001. Conclusion. The ABMps model allows the estimation of airway pressure drop at each bronchial generation with patient-specific physiological measurements and can be generated from data measured at the bedside. The distribution of patient-specific α values indicates that the overall ABM can be readily improved to better match observed data and capture patient condition.

  3. Evaluation of Endotracheal Tube Scraping on Airway Resistance.

    Science.gov (United States)

    Scott, J Brady; Dubosky, Meagan N; Vines, David L; Sulaiman, Adewunmi S; Jendral, Kyle R; Singh, Gagan; Patel, Ankeet; Kaplan, Carl A; Gurka, David P; Balk, Robert A

    2017-11-01

    Spontaneous breathing trials (SBTs) are used to assess the readiness for discontinuation of mechanical ventilation. When airway resistance (R aw ) is elevated, the imposed work of breathing can lead to prolongation of mechanical ventilation. Biofilm and mucus build-up within the endotracheal tube (ETT) can increase R aw . Scraping the ETT can remove the biofilm build-up and decrease mechanical R aw . The primary aim of this study was to evaluate the impact of ETT scraping on R aw . The secondary aim was to determine whether decreasing R aw would impact subsequent SBT success. Intubated, mechanically ventilated subjects were enrolled if they failed an SBT and had an R aw of > 10 cm H 2 O/L/s. SBT failure was based on institutional guidelines, and R aw was calculated by subtracting the difference between the measured peak and plateau pressures using a square flow waveform with an inspiratory flow set at 60 L/min. The endOclear device was inserted into the ETT and withdrawn per manufacturer's guidelines. Scraping was repeated until the ETT was cleared. Change in R aw was compared pre- and post-ETT scraping using a paired t test. A Mann-Whitney U test evaluated the difference in percentage change in R aw between SBT groups. Twenty-nine subjects completed the study. The mean pre- and post-ETT scraping R aw values were 15.17 ± 3.83 and 12.05 ± 3.19 cm H 2 O/L/s, respectively ( P < .001). Subsequent SBT success was 48%; however, there was no difference in percentage change in R aw between subsequent passed SBT (18.61% [interquartile range 8.90-33.93%]) and failed SBT (23.88% [interquartile range 0.00-34.80%]), U = 78.5, z = -0.284, P = .78. No adverse events were noted with ETT scraping. This study demonstrated that ETT scraping can reduce R aw . The decrease in R aw post-ETT scraping did not affect subsequent SBT success. Copyright © 2017 by Daedalus Enterprises.

  4. Effect of inspiration on airway dimensions measured in maximal inspiration CT images of subjects without airflow limitation

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Jens; Raket, Lars Lau; Nielsen, Mads [University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Wille, Mathilde M.W.; Dirksen, Asger [University of Copenhagen, Department of Respiratory Medicine, Gentofte Hospital, Hellerup (Denmark); Feragen, Aasa [University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Max Planck Institute for Intelligent Systems and Max Planck Institute for Developmental Biology, Tuebingen (Germany); Pedersen, Jesper H. [Rigshospitalet, University Hospital of Copenhagen, Department of Cardio-Thoracic Surgery RT, Copenhagen (Denmark); Bruijne, Marleen de [University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Erasmus MC Rotterdam, Departments of Medical Informatics and Radiology, Rotterdam (Netherlands)

    2014-09-15

    To study the effect of inspiration on airway dimensions measured in voluntary inspiration breath-hold examinations. 961 subjects with normal spirometry were selected from the Danish Lung Cancer Screening Trial. Subjects were examined annually for five years with low-dose CT. Automated software was utilized to segment lungs and airways, identify segmental bronchi, and match airway branches in all images of the same subject. Inspiration level was defined as segmented total lung volume (TLV) divided by predicted total lung capacity (pTLC). Mixed-effects models were used to predict relative change in lumen diameter (ALD) and wall thickness (AWT) in airways of generation 0 (trachea) to 7 and segmental bronchi (R1-R10 and L1-L10) from relative changes in inspiration level. Relative changes in ALD were related to relative changes in TLV/pTLC, and this distensibility increased with generation (p < 0.001). Relative changes in AWT were inversely related to relative changes in TLV/pTLC in generation 3-7 (p < 0.001). Segmental bronchi were widely dispersed in terms of ALD (5.7 ± 0.7 mm), AWT (0.86 ± 0.07 mm), and distensibility (23.5 ± 7.7 %). Subjects who inspire more deeply prior to imaging have larger ALD and smaller AWT. This effect is more pronounced in higher-generation airways. Therefore, adjustment of inspiration level is necessary to accurately assess airway dimensions. (orig.)

  5. Tunable Quantum Spin Liquidity in the 1 /6 th-Filled Breathing Kagome Lattice

    Science.gov (United States)

    Akbari-Sharbaf, A.; Sinclair, R.; Verrier, A.; Ziat, D.; Zhou, H. D.; Sun, X. F.; Quilliam, J. A.

    2018-06-01

    We present measurements on a series of materials, Li2 In1 -xScx Mo3 O8 , that can be described as a 1 /6 th-filled breathing kagome lattice. Substituting Sc for In generates chemical pressure which alters the breathing parameter nonmonotonically. Muon spin rotation experiments show that this chemical pressure tunes the system from antiferromagnetic long range order to a quantum spin liquid phase. A strong correlation with the breathing parameter implies that it is the dominant parameter controlling the level of magnetic frustration, with increased kagome symmetry generating the quantum spin liquid phase. Magnetic susceptibility measurements suggest that this is related to distinct types of charge order induced by changes in lattice symmetry, in line with the theory of Chen et al. [Phys. Rev. B 93, 245134 (2016), 10.1103/PhysRevB.93.245134]. The specific heat for samples at intermediate Sc concentration, which have the minimum breathing parameter, show consistency with the predicted U (1 ) quantum spin liquid.

  6. [Possibilities of bi-level positive pressure ventilation in chronic hypoventilation].

    Science.gov (United States)

    Saaresranta, Tarja; Anttalainen, Ulla; Polo, Olli

    2011-01-01

    During the last decade, noninvasive bi-level positive pressure ventilation has enabled respiratory support in inpatient wards and at home. In many cases, a bi-level airway pressure ventilator can be used to avoid artificial airway and respirator therapy, and may shorten hospital stay and save costs. The treatment alleviates the patient's dyspnea and fatigue, whereby the quality of life improves, and in certain situations also the life span increases. The implementation of bi-level positive pressure ventilation by the physician requires knowledge of the basics of respiratory physiology and familiarization with the bi-level airway pressure ventilator.

  7. Trefoil factor-2 reverses airway remodeling changes in allergic airways disease.

    Science.gov (United States)

    Royce, Simon G; Lim, Clarice; Muljadi, Ruth C; Samuel, Chrishan S; Ververis, Katherine; Karagiannis, Tom C; Giraud, Andrew S; Tang, Mimi L K

    2013-01-01

    Trefoil factor 2 (TFF2) is a small peptide with an important role in mucosal repair. TFF2 is up-regulated in asthma, suggesting a role in asthma pathogenesis. Given its known biological role in promoting epithelial repair, TFF2 might be expected to exert a protective function in limiting the progression of airway remodeling in asthma. The contribution of TFF2 to airway remodeling in asthma was investigated by examining the expression of TFF2 in the airway and lung, and evaluating the effects of recombinant TFF2 treatment on established airway remodeling in a murine model of chronic allergic airways disease (AAD). BALB/c mice were sensitized and challenged with ovalbumin (OVA) or saline for 9 weeks, whereas mice with established OVA-induced AAD were treated with TFF2 or vehicle control (intranasally for 14 d). Effects on airway remodeling, airway inflammation, and airway hyperresponsiveness were then assessed, whereas TFF2 expression was determined by immunohistochemistry. TFF2 expression was significantly increased in the airways of mice with AAD, compared with expression levels in control mice. TFF2 treatment resulted in reduced epithelial thickening, subepithelial collagen deposition, goblet-cell metaplasia, bronchial epithelium apoptosis, and airway hyperresponsiveness (all P < 0.05, versus vehicle control), but TFF2 treatment did not influence airway inflammation. The increased expression of endogenous TFF2 in response to chronic allergic inflammation is insufficient to prevent the progression of airway inflammation and remodeling in a murine model of chronic AAD. However, exogenous TFF2 treatment is effective in reversing aspects of established airway remodeling. TFF2 has potential as a novel treatment for airway remodeling in asthma.

  8. [Successful airway management using i-gel in 7 patients undergoing awake craniotomy].

    Science.gov (United States)

    Matsunami, Katsuaki; Sanuki, Michiyoshi; Yasuuji, Masakazu; Nakanuno, Ryuichi; Kato, Takahiro; Kawamoto, Masashi

    2014-07-01

    In order to secure airway during awake craniotomy, we used i-gel to perform positive-pressure ventilation in 7 patients for their anesthetic management. During removal of a tumor around the motor speech center, anesthetic management including asleep-awake-asleep technique was applied for speech testing. The technique, insertion and re-insertion of i-gel, was needed and it was easy in all the patients. During positive-pressure ventilation, peak pressure, tidal volume both for inspiration and expiration, and endtidal-CO2 were not markedly altered. Leakage around i-gel, and its differences between inspiration and expiration were negligible, while the tidal volume was adequate. We conclude that i-gel is useful for anesthetic management for awake craniotomy procedure for both securing airway and ventilation.

  9. Tissue sensitivity of the rat upper and lower extrapulmonary airways to the inhaled electrophilic air pollutants diacetyl and acrolein.

    Science.gov (United States)

    Cichocki, Joseph A; Smith, Gregory J; Morris, John B

    2014-11-01

    The target site for inhaled vapor-induced injury often differs in mouth-breathing humans compared with nose-breathing rats, thus complicating the use of rat inhalation toxicity data for assessment of human risk. We sought to examine sensitivity of respiratory/transitional nasal (RTM) and tracheobronchial (TBM) mucosa to two electrophilic irritant vapors: diacetyl and acrolein. Computational fluid dynamic physiologically based pharmacokinetic modeling was coupled with biomarker assessment to establish delivered dose-response relationships in RTM and TBM in male F344 rats following 6 h exposure to diacetyl or acrolein. Biomarkers included glutathione status, proinflammatory and antioxidant gene mRNA levels, and nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Modeling revealed that 0.0094-0.1653 μg acrolein/min-cm(2) and 3.9-21.6 μg diacetyl/min-cm(2) were deposited into RTM/TBM. Results indicate RTM and TBM were generally of similar sensitivity to diacetyl and acrolein. For instance, both tissues displayed induction of antioxidant and proinflammatory genes, and nuclear accumulation of Nrf2 after electrophile exposure. Hierarchical cellular response patterns were similar in RTM and TBM but differed between vapors. Specifically, diacetyl exposure induced proinflammatory and antioxidant genes concomitantly at low exposure levels, whereas acrolein induced antioxidant genes at much lower exposure levels than that required to induce proinflammatory genes. Generally, diacetyl was less potent than acrolein, as measured by maximal induction of transcripts. In conclusion, the upper and lower extrapulmonary airways are of similar sensitivity to inhaled electrophilic vapors. Dosimetrically based extrapolation of nasal responses in nose-breathing rodents may provide an approach to predict risk to the lower airways of humans during mouth-breathing. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All

  10. Experience of nasal continuous positive airway pressure (cpap) by infant flow driver in a neonatal unit of a developing country

    International Nuclear Information System (INIS)

    Iqbal, A.; Waqar, T.; Safdar, C.A.; Iqbal, T.

    2014-01-01

    Objective: To study the safety and efficacy of nasal continuous positive airways pressure by infant flow drivers in neonates admitted with respiratory problems. Study Design: Quasi-experimental study. Place and Duration of Study: This study was conducted at CMH Lahore from April 2012 to March 2013. Subjects and Methods: All infants who were treated with nasal continuous positive airway pressure (nCPAP) for various indications at neonatal intensive care unit (NICU) of CMH Lahore were evaluated for gestational, age, weight, gender, indications and duration on nCPAP, pre-defined outcomes, complications and length of hospital stay. Efficacy was defined as the ability to manage an infant on nCPAP alone thus avoiding the need for mechanical ventilation. Results: During the study period, 343 neonates were admitted in NICU, forty five neonates were placed on nCPAP. Mean gestational age was 33.85+ 3 weeks. Mean weight was 2043 + 770 grams. Main indications for applying nCPAP were respiratory distress syndrome (48.9%) and neonatal pneumonia (17.8%). Most common complication was abdominal distension (6.7%). Out of 45 infants placed on nCPAP, 32 (71.1%) were managed on nCPAP alone while 13 (28.9%) needed mechanical ventilation after nCPAP failure. Conclusion: Nasal CPAP by an infant flow driver is a useful method to manage respiratory distress in neonates. It reduces the need for mechanical ventilation and can be used as first line respiratory support before mechanical ventilation. (author)

  11. Evaluation of obstructive airway lesions in complex congenital heart disease using composite volume-rendered images from multislice CT

    International Nuclear Information System (INIS)

    Choo, Ki Seok; Kim, Chang Won; Lee, Tae Hong; Kim, Suk; Kim, Kun Il; Lee, Hyoung Doo; Ban, Ji Eun; Sung, Si Chan; Chang, Yun Hee

    2006-01-01

    Multislice CT (MSCT) allows high-quality volume-rendered (VR) and composite volume-rendered images. To investigate the clinical usefulness of composite VR images in the evaluation of the relationship between cardiovascular structures and the airway in children with complex congenital heart disease (CHD). Four- or 16-slice MSCT scanning was performed consecutively in 77 children (mean age 6.4 months) with CHD and respiratory symptoms, a chest radiographic abnormality, or abnormal course of the pulmonary artery on ECHO. MSCT scanning was performed during breathing or after sedation. Contrast medium (2 ml/kg) was administered through a pedal venous route or arm vein in all patients. The VR technique was used to reconstruct the cardiovascular structures and airway, and then both VR images were composed using the commercial software (VoxelPlus 2 ; Daejeon, Korea). Stenoses were seen in the trachea in 1 patient and in the bronchi in 14 patients (19%). Other patients with complex CHD did not have significant airway stenoses. Composite VR images with MSCT can provide more exact airway images in relationship to the surrounding cardiovascular structures and thus help in optimizing management strategies in treating CHD. (orig.)

  12. Evaluation of a new simple collection device for sampling of microparticles in exhaled breath.

    Science.gov (United States)

    Seferaj, Sabina; Ullah, Shahid; Tinglev, Åsa; Carlsson, Sten; Winberg, Jesper; Stambeck, Peter; Beck, Olof

    2018-03-12

    The microparticle fraction of exhaled breath is of interest for developing clinical biomarkers. Exhaled particles may contain non-volatile components from all parts of the airway system, formed during normal breathing. This study aimed to evaluate a new, simple sampling device, based on impaction, for collecting microparticles from exhaled breath. Performance of the new device was compared with that of the existing SensAbues membrane filter device. The analytical work used liquid chromatography-tandem mass spectrometry methods. The new device collected three subsamples and these were separately analysed from eight individuals. No difference was observed between the centre position (0.91 ng/sample) and the side positions (1.01 ng/sample) using major phosphatidylcholine (PC) 16:0/16:0 as the analyte. Exhaled breath was collected from eight patients on methadone maintenance treatment. The intra-individual variability in measured methadone concentration between the three collectors was 8.7%. In another experiment using patients on methadone maintenance treatment, the sampling efficiency was compared with an established filter device. Compared to the existing device, the efficiency of the new device was 121% greater for methadone and 1450% greater for DPPC. The data from lipid analysis also indicated that a larger fraction of the collected material was from the distal parts. Finally, a study using an optical particle counter indicated that the device preferentially collects the larger particle fraction. In conclusion, this study demonstrates the usefulness of the new device for collecting non-volatile components from exhaled breath. The performance of the device was superior to the filter device in several aspects.

  13. Positive pressure ventilation and cranial volume in newborn infants.

    OpenAIRE

    Milligan, D W

    1981-01-01

    The relationship between changes in airways pressure, pleural pressure, and cranial volume was studied in a group of sick newborn infants requiring ventilatory assistance. Cranial volume increased appreciably only when lung compliance was such that more than 20% of the applied airways pressure was transmitted to the pleural space, or if the absolute pleural pressure was greater than 4 cmH2O above atmospheric pressure. The findings stress the need for more-critical monitoring during periods of...

  14. Effect of oxygen and heliox breathing on air bubbles in adipose tissue during 25-kPa altitude exposures

    DEFF Research Database (Denmark)

    Randsoe, T.; Kvist, T.M.; Hyldegaard, O.

    2008-01-01

    and heliox breathing. Preoxygenation enhanced bubble disappearance compared with oxygen and heliox breathing but did not prevent bubble growth. The results indicate that oxygen breathing at 25 kPa promotes air bubble growth in adipose tissue regardless of the tissue nitrogen pressure Udgivelsesdato: 2008/11...

  15. Relationship between regional ventilation and aerosol deposition in tidal breathing

    Energy Technology Data Exchange (ETDEWEB)

    Trajan, M.; Logus, J.W.; Enns, E.G.; Man, S.F.

    1984-07-01

    The regional distribution of the deposition of 1.2 micron particles of 99mTc sulfur colloid inhaled by tidal breathing was compared with the distribution of ventilation as measured by a 133Xe washout technique. Twelve subjects were studied, 6 with normal pulmonary function tests, 5 with air-flow limitation, and 1 with unilateral phrenic nerve paralysis. Both xenon and aerosol were inhaled at tidal volume by the subjects while seated upright. A large field gamma camera acquired posterior scans. Thirteen experiments were also done on 7 dogs: 1 with extrathoracic obstruction of the airway to 1 lung, and 12 with bronchoconstriction from the instillation of methacholine chloride into the airways of a lower lobe. Two of these dogs were studied with a gamma camera system, and the others were studied with a Picker multi-probe system. Both in humans and in dogs, an increase in time constant, which indicated a decrease in ventilation, was associated with an increase in peripheral aerosol deposition when normalized for ventilation. It is suggested that the increased residence time is responsible for the increased deposition in regions that received lesser ventilation.

  16. Relationship between regional ventilation and aerosol deposition in tidal breathing

    International Nuclear Information System (INIS)

    Trajan, M.; Logus, J.W.; Enns, E.G.; Man, S.F.

    1984-01-01

    The regional distribution of the deposition of 1.2 micron particles of 99mTc sulfur colloid inhaled by tidal breathing was compared with the distribution of ventilation as measured by a 133Xe washout technique. Twelve subjects were studied, 6 with normal pulmonary function tests, 5 with air-flow limitation, and 1 with unilateral phrenic nerve paralysis. Both xenon and aerosol were inhaled at tidal volume by the subjects while seated upright. A large field gamma camera acquired posterior scans. Thirteen experiments were also done on 7 dogs: 1 with extrathoracic obstruction of the airway to 1 lung, and 12 with bronchoconstriction from the instillation of methacholine chloride into the airways of a lower lobe. Two of these dogs were studied with a gamma camera system, and the others were studied with a Picker multi-probe system. Both in humans and in dogs, an increase in time constant, which indicated a decrease in ventilation, was associated with an increase in peripheral aerosol deposition when normalized for ventilation. It is suggested that the increased residence time is responsible for the increased deposition in regions that received lesser ventilation

  17. Nasal airway and septal variation in unilateral and bilateral cleft lip and palate.

    Science.gov (United States)

    Starbuck, John M; Friel, Michael T; Ghoneima, Ahmed; Flores, Roberto L; Tholpady, Sunil; Kula, Katherine

    2014-10-01

    Cleft lip and palate (CLP) affects the dentoalveolar and nasolabial facial regions. Internal and external nasal dysmorphology may persist in individuals born with CLP despite surgical interventions. 7-18 year old individuals born with unilateral and bilateral CLP (n = 50) were retrospectively assessed using cone beam computed tomography. Anterior, middle, and posterior nasal airway volumes were measured on each facial side. Septal deviation was measured at the anterior and posterior nasal spine, and the midpoint between these two locations. Data were evaluated using principal components analysis (PCA), multivariate analysis of variance (MANOVA), and post-hoc ANOVA tests. PCA results show partial separation in high dimensional space along PC1 (48.5% variance) based on age groups and partial separation along PC2 (29.8% variance) based on CLP type and septal deviation patterns. MANOVA results indicate that age (P = 0.007) and CLP type (P ≤ 0.001) significantly affect nasal airway volume and septal deviation. ANOVA results indicate that anterior nasal volume is significantly affected by age (P ≤ 0.001), whereas septal deviation patterns are significantly affected by CLP type (P ≤ 0.001). Age and CLP type affect nasal airway volume and septal deviation patterns. Nasal airway volumes tend to be reduced on the clefted sides of the face relative to non-clefted sides of the face. Nasal airway volumes tend to strongly increase with age, whereas septal deviation values tend to increase only slightly with age. These results suggest that functional nasal breathing may be impaired in individuals born with the unilateral and bilateral CLP deformity. © 2014 Wiley Periodicals, Inc.

  18. Routine use of humidification with nasal continuous positive airway pressure.

    Science.gov (United States)

    Worsnop, C J; Miseski, S; Rochford, P D

    2010-09-01

    Heated humidification can reduce nasal symptoms caused by continuous positive airway pressure (CPAP) treatment, but its routine use has not been studied over the medium term in a randomized controlled trial. The aim of this study is to determine if heated humidification would reduce nasal symptoms and improve adherence with CPAP treatment in all patients with sleep apnoea irrespective of whether they had nasal symptoms initially. A randomized, parallel group design. Patients were treated for 3 months with a Fisher & Paykel HC201 pump with built-in heated humidification, or with the heater disabled and without water. Adherence was measured with a timer built into the pumps. Nasal symptoms were measured with a 10-cm visual analogue scale. There were 25 in the humidification group and 29 in the non-humidification group. After 12 weeks mean (standard deviation) adherence with CPAP was 4.7 (2.4) and 4.5 (2.2) hours per night respectively. Nasal symptoms that were reduced were nose blocked* 6 (12), 18 (26); sneezing* 4 (8), 15 (25); dry nose* 8 (12), 24 (33); stuffy nose* 7 (14), 22(31); dry mouth* 13 (18), 33(36); and runny nose* 6 (17), 14 (29). Parameters marked with an asterisk '*' had P humidification with CPAP in all patients with sleep apnoea reduced nasal symptoms, but did not improve adherence. © 2010 The Authors. Internal Medicine Journal © 2010 Royal Australasian College of Physicians.

  19. Medical Issues: Breathing

    Science.gov (United States)

    ... Information Packets Equipment Pool Living With SMA Medical Issues Palliative Breathing Orthopedics Nutrition Equipment Daily Life At ... curesma.org > support & care > living with sma > medical issues > breathing Breathing Breathing problems are the most common ...

  20. IMAGE-BASED IN VIVO QUANTITATIVE ASSESSMENT OF HUMAN AIRWAY OPENING AND CONTRACTILITY BY FIBER OPTICAL NASOPHARYNGOSCOPY IN HEALTHY AND ASTHMATIC SUBJECTS

    Directory of Open Access Journals (Sweden)

    LINHONG DENG

    2013-04-01

    Full Text Available Assessment of human airway lumen opening is important in diagnosing and understanding the mechanisms of airway dysfunctions such as the excessive airway narrowing in asthma and chronic obstructive pulmonary disease (COPD. Although there are indirect methods to evaluate the airway calibre, direct in vivo measurement of the airway calibre has not been commonly available. With recent advent of the flexible fiber optical nasopharyngoscope with video recording it has become possible to directly visualize the passages of upper and lower airways. However, quantitative analysis of the recorded video images has been technically challenging. Here, we describe an automatic image processing and analysis method that allows for batch analysis of the images recorded during the endoscopic procedure, thus facilitates image-based quantification of the airway opening. Video images of the airway lumen of volunteer subject were acquired using a fiber optical nasopharyngoscope, and subsequently processed using Gaussian smoothing filter, threshold segmentation, differentiation, and Canny image edge detection, respectively. Thus the area of the open airway lumen was identified and computed using a predetermined converter of the image scale to true dimension of the imaged object. With this method we measured the opening/narrowing of the glottis during tidal breathing with or without making "Hee" sound or cough. We also used this method to measure the opening/narrowing of the primary bronchus of either healthy or asthmatic subjects in response to histamine and/or albuterol treatment, which also provided an indicator of the airway contractility. Our results demonstrate that the image-based method accurately quantified the area change waveform of either the glottis or the bronchus as observed by using the optical nasopharygoscope. Importantly, the opening/narrowing of the airway lumen generally correlated with the airflow and resistance of the airways, and could

  1. Characterizing adult human nasal airway dimensions

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Griffith, W.C.

    1994-01-01

    Respiratory tract models used in calculating radiation dose from exposure to inhaled radioactive aerosols have only recently focused attention on the importance of the nasal airways (NAs). Because the NAs are the first tissues of the respiratory tract available for aerosol deposition in normally nose-breathing people, any deposition of aerosol in this anatomical structure will reduce the amounts available to be deposited in the remainder of the respiratory tract. Thus, uncertainties in estimating the deposition fractions in the NAs will propagate throughout the remainder of the respiratory tract, creating errors in the calculated dose estimates. Additionally, there is evidence that the NAs are also at risk for induction of cancer from exposure to certain occupational aerosols such as wood dust, leather dust, chromium, and nickel. The purpose of this investigation was to conduct an anatomical study to assess the variabilities in NA dimensions

  2. Influence of Head and Neck Position on Oropharyngeal Leak Pressure and Cuff Position with the ProSeal Laryngeal Mask Airway and the I-Gel: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar Mishra

    2015-01-01

    Full Text Available Background. This study was designed to assess and compare the effect of head and neck position on the oropharyngeal leak pressures and cuff position (employing fibreoptic view of the glottis and ventilation scores between ProSeal LMA and the I-gel. Material and Methods. After induction of anesthesia, the supraglottic device was inserted and ventilation confirmed. The position of the head was randomly changed from neutral to flexion, extension, and lateral rotation (left. The oropharyngeal leak pressures, fibreoptic view of glottis, ventilation scores, and delivered tidal volumes and end tidal CO2 were noted in all positions. Results. In both groups compared with neutral position, oropharyngeal leak pressures were significantly higher with flexion and lower with extension but similar with rotation of head and neck. However the oropharyngeal leak pressure was significantly higher for ProSeal LMA compared with the I-gel in all positions. Peak airway pressures were significantly higher with flexion in both groups (however this did not affect ventilation, lower with extension in ProSeal group, and comparable in I-gel group but did not change significantly with rotation of head and neck in both groups. Conclusion. Effective ventilation can be done with both ProSeal LMA and I-gel with head in all the above positions. ProSeal LMA has a better margin of safety than I-gel due to better sealing pressures except in flexion where the increase in airway pressure is more with the former. Extreme precaution should be taken in flexion position in ProSeal LMA.

  3. Social Stress Induced Pressure Breathing and Consequent Blood Pressure Oscillation

    NARCIS (Netherlands)

    Fokkema, Dirk S.; Koolhaas, Jaap M.; Meulen, Jan van der; Schoemaker, Regien

    1986-01-01

    A large amplitude blood pressure oscillation occurs during social defeat in a territorial fight between male rats, and during the application of a psychosocial stimulus associated with this defeat. Synchronous recording of blood pressure, intrathoracic pressure and diaphragm activity shows that the

  4. Positive airway pressure treatment

    Science.gov (United States)

    ... it. After using PAP regularly, you may notice: Better concentration and memory Feeling more alert and less sleepy during the day Improved sleep for your bed partner Being more productive at ... and a better mood Normal sleep patterns Lower blood pressure (in ...

  5. Optimal level of continuous positive airway pressure: auto-adjusting titration versus titration with a predictive equation.

    Science.gov (United States)

    Choi, Ji Ho; Jun, Young Joon; Oh, Jeong In; Jung, Jong Yoon; Hwang, Gyu Ho; Kwon, Soon Young; Lee, Heung Man; Kim, Tae Hoon; Lee, Sang Hag; Lee, Seung Hoon

    2013-05-01

    The aims of the present study were twofold. We sought to compare two methods of titrating the level of continuous positive airway pressure (CPAP) - auto-adjusting titration and titration using a predictive equation - with full-night manual titration used as the benchmark. We also investigated the reliability of the two methods in patients with obstructive sleep apnea syndrome (OSAS). Twenty consecutive adult patients with OSAS who had successful, full-night manual and auto-adjusting CPAP titration participated in this study. The titration pressure level was calculated with a previously developed predictive equation based on body mass index and apnea-hypopnea index. The mean titration pressure levels obtained with the manual, auto-adjusting, and predictive equation methods were 9.0 +/- 3.6, 9.4 +/- 3.0, and 8.1 +/- 1.6 cm H2O,respectively. There was a significant difference in the concordance within the range of +/- 2 cm H2O (p = 0.019) between both the auto-adjusting titration and the titration using the predictive equation compared to the full-night manual titration. However, there was no significant difference in the concordance within the range of +/- 1 cm H2O (p > 0.999). When compared to full-night manual titration as the standard method, auto-adjusting titration appears to be more reliable than using a predictive equation for determining the optimal CPAP level in patients with OSAS.

  6. Kidney motion during free breathing and breath hold for MR-guided radiotherapy

    International Nuclear Information System (INIS)

    Stam, Mette K; Van Vulpen, Marco; Intven, Martijn; Crijns, Sjoerd P M; Lagendijk, Jan J W; Raaymakers, Bas W; Barendrecht, Maurits M; Zonnenberg, Bernard A

    2013-01-01

    Current treatments for renal cell carcinoma have a high complication rate due to the invasiveness of the treatment. With the MRI-linac it may be possible to treat renal tumours non-invasively with high-precision radiotherapy. This is expected to reduce complications. To deliver a static dose distribution, radiation gating will be used. In this study the reproducibility and efficiency of free breathing gating and a breath hold treatment of the kidney was investigated. For 15 patients with a renal lesion the kidney motion during 2 min of free breathing and 10 consecutive expiration breath holds was studied with 2D cine MRI. The variability in kidney expiration position and treatment efficiency for gating windows of 1 to 20 mm was measured for both breathing patterns. Additionally the time trend in free breathing and the variation in expiration breath hold kidney position with baseline shift correction was determined. In 80% of the patients the variation in expiration position during free breathing is smaller than 2 mm. No clinically relevant time trends were detected. The variation in expiration breath hold is for all patients larger than the free breathing expiration variation. Gating on free breathing is, for gating windows of 1 to 5 mm more efficient than breath hold without baseline correction. When applying a baseline correction to the breath hold it increases the treatment efficiency. The kidney position is more reproducible in expiration free breathing than non-guided expiration breath hold. For small gating windows it is also more time efficient. Since free breathing also seems more comfortable for the patients it is the preferred breathing pattern for MRI-Linac treatments of the kidney. (paper)

  7. 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

  8. Relationship between loss in parenchymal elastic recoil pressure and maximal airway narrowing in subjects with alpha1-antitrypsin deficiency

    NARCIS (Netherlands)

    Cheung, D.; Schot, R.; Zwinderman, A. H.; Zagers, H.; Dijkman, J. H.; Sterk, P. J.

    1997-01-01

    Airway hyperresponsiveness is characterized by an increase in sensitivity and excessive airway narrowing to inhaled bronchoconstrictor stimuli. There is experimental evidence that maximal airway narrowing is related to lung elasticity in normal and asthmatic subjects. We hypothesized that reduced

  9. Open-lung protective ventilation with pressure control ventilation, high-frequency oscillation, and intratracheal pulmonary ventilation results in similar gas exchange, hemodynamics, and lung mechanics.

    Science.gov (United States)

    Sedeek, Khaled A; Takeuchi, Muneyuki; Suchodolski, Klaudiusz; Vargas, Sara O; Shimaoka, Motomu; Schnitzer, Jay J; Kacmarek, Robert M

    2003-11-01

    Pressure control ventilation (PCV), high-frequency oscillation (HFO), and intratracheal pulmonary ventilation (ITPV) may all be used to provide lung protective ventilation in acute respiratory distress syndrome, but the specific approach that is optimal remains controversial. Saline lavage was used to produce acute respiratory distress syndrome in 21 sheep randomly assigned to receive PCV, HFO, or ITPV as follows: positive end-expiratory pressure (PCV and ITPV) and mean airway pressure (HFO) were set in a pressure-decreasing manner after lung recruitment that achieved a ratio of Pao2/Fio2 > 400 mmHg. Respiratory rates were 30 breaths/min, 120 breaths/min, and 8 Hz, respectively, for PCV, ITPV, and HFO. Eucapnia was targeted with peak carinal pressure of no more than 35 cm H2O. Animals were then ventilated for 4 h. There were no differences among groups in gas exchange, lung mechanics, or hemodynamics. Tidal volume (PCV, 8.9 +/- 2.1 ml/kg; ITPV, 2.7 +/- 0.8 ml/kg; HFO, approximately 2.0 ml/kg) and peak carinal pressure (PCV, 30.6 +/- 2.6 cm H2O; ITPV, 22.3 +/- 4.8 cm H2O; HFO, approximately 24.3 cm H2O) were higher in PCV. Pilot histologic data showed greater interstitial hemorrhage and alveolar septal expansion in PCV than in HFO or ITPV. These data indicate that HFO, ITPV, and PCV when applied with an open-lung protective ventilatory strategy results in the same gas exchange, lung mechanics, and hemodynamic response, but pilot data indicate that lung injury may be greater with PCV.

  10. Respiratory physiology during early life.

    Science.gov (United States)

    Stocks, J

    1999-08-01

    Despite the rapid adaptation to extrauterine life, the respiratory system of an infant is not simply a miniaturized version of that of an adult, since the rapid somatic growth that occurs during the first year of life is accompanied by major developmental changes in respiratory physiology. The highly compliant chest wall of the infant results in relatively low transpulmonary pressures at end expiration with increased tendency of the small peripheral airways to close during tidal breathing. This not only impairs gas exchange and ventilation-perfusion balance, particularly in dependent parts of the lung, but, together with the small absolute size of the airways, renders the infant and young child particularly susceptible to airway obstruction. Premature airways are highly compliant structures compared with those of mature newborns or adults. This increased compliance can cause airway collapse, resulting in increased airways resistance, flow limitation, poor gas exchange and increased work of breathing. Although there is clear evidence that airway reactivity is present from birth, its role in wheezing lower respiratory tract illnesses in young infants may be overshadowed by pre-existing abnormalities of airway geometry and lung mechanics, or by pathological changes such as airway oedema and mucus hypersecretion. Attempts to assess age-related changes in airway reactivity or response to aerosol therapy in the very young is confounded by changes in breathing patterns and the fact that infants are preferential nose breathers. There is increasing evidence that pre-existing abnormalities of respiratory function, associated with adverse events during foetal life (including maternal smoking during pregnancy), and familial predisposition to wheezing are important determinants of wheezing illnesses during the first years of life. This emphasizes the need to identify and minimize any factors that threaten the normal development of the lung during this critical period if

  11. HEMODYNAMIC STATUS IN AIRWAY MANAGEMENT DURING GENERAL ANESTHESIA: COMPARISON OF THREE METHODS

    OpenAIRE

    K MONTAZERI; KH NAGHIBI; A.A AKHOUNDI

    2000-01-01

    Introduction. The laryngeal mask airway (LMA) was recently introduced in general anesthesia as an alternative to the face mask or tracheal intubation for airway maintenance. Methods. The effects of LMA insertion, face mask or tracheal intubation on homodynamic status were studied in 195 normotensive patients who underwent elective transurethral lithotripsy (TUL). The patients were monitored with blood pressure measurement and pulse oximetry. Anesthesia was induced with sodium thiopental,...

  12. Characteristics of turbulent particle transport in human airways under steady and cyclic flows

    International Nuclear Information System (INIS)

    Jedelsky, Jan; Lizal, Frantisek; Jicha, Miroslav

    2012-01-01

    Highlights: ► PDA data allow to estimate PSD of particle velocity fluctuations in realistic model. ► PSD of micron-sized particles is independent of their size up to 700 Hz. ► Such particles follow air flow and turb. diffusion contributes to their deposition. ► Cyclic flow PSDs contain more TKE at high freq. than equivalent steady-flow PSDs. ► Exp. breathing phase differs from insp. phase at high frequency part of the spectra. - Abstract: Motion of monodispersed aerosol particles suspended in air flow has been studied on realistic transparent model of human airways using Phase Doppler Particle Analyser (P/DPA). Time-resolved velocity data for particles in size range 1–8 μm were processed using Fuzzy Slotting Technique to estimate the power spectral density (PSD) of velocity fluctuations. The optimum processing setup for our data was found and recommendations for future experiments to improve PSD quality were suggested. Typical PSD plots at mainstream positions of the trachea and the upper bronchi are documented and differences among (1) steady-flow regimes and equivalent cyclic breathing regimes, (2) inspiration and expiration breathing phase and (3) behaviour of particles of different sizes are described in several positions of the airway model. Systematically higher level of velocity fluctuations in the upper part of the frequency range (30–500 Hz) was found for cyclic flows in comparison with corresponding steady flows. Expiratory flows in both the steady and cyclic cases produce more high-frequency fluctuations compared to inspiratory flows. Negligible differences were found for flow of particles in the inspected size range 1–8 μm at frequencies below 500 Hz. This finding was explained by Stokes number analysis. Implied match of the air and particle flows thereby indicates turbulent diffusion as important deposition mechanism and confirms the capability to use the P/DPA data as the air flow velocity estimate.

  13. Influence of bronchial diameter change on the airflow dynamics based on a pressure-controlled ventilation system.

    Science.gov (United States)

    Ren, Shuai; Cai, Maolin; Shi, Yan; Xu, Weiqing; Zhang, Xiaohua Douglas

    2018-03-01

    Bronchial diameter is a key parameter that affects the respiratory treatment of mechanically ventilated patients. In this paper, to reveal the influence of bronchial diameter on the airflow dynamics of pressure-controlled mechanically ventilated patients, a new respiratory system model is presented that combines multigeneration airways with lungs. Furthermore, experiments and simulation studies to verify the model are performed. Finally, through the simulation study, it can be determined that in airway generations 2 to 7, when the diameter is reduced to half of the original value, the maximum air pressure (maximum air pressure in lungs) decreases by nearly 16%, the maximum flow decreases by nearly 30%, and the total airway pressure loss (sum of each generation pressure drop) is more than 5 times the original value. Moreover, in airway generations 8 to 16, with increasing diameter, the maximum air pressure, maximum flow, and total airway pressure loss remain almost constant. When the diameter is reduced to half of the original value, the maximum air pressure decreases by 3%, the maximum flow decreases by nearly 5%, and the total airway pressure loss increases by 200%. The study creates a foundation for improvement in respiratory disease diagnosis and treatment. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Sustained inflation and incremental mean airway pressure trial during conventional and high-frequency oscillatory ventilation in a large porcine model of acute respiratory distress syndrome

    Directory of Open Access Journals (Sweden)

    Wunder Christian

    2006-06-01

    Full Text Available Abstract Background To compare the effect of a sustained inflation followed by an incremental mean airway pressure trial during conventional and high-frequency oscillatory ventilation on oxygenation and hemodynamics in a large porcine model of early acute respiratory distress syndrome. Methods Severe lung injury (Ali was induced in 18 healthy pigs (55.3 ± 3.9 kg, mean ± SD by repeated saline lung lavage until PaO2 decreased to less than 60 mmHg. After a stabilisation period of 60 minutes, the animals were randomly assigned to two groups: Group 1 (Pressure controlled ventilation; PCV: FIO2 = 1.0, PEEP = 5 cmH2O, VT = 6 ml/kg, respiratory rate = 30/min, I:E = 1:1; group 2 (High-frequency oscillatory ventilation; HFOV: FIO2 = 1.0, Bias flow = 30 l/min, Amplitude = 60 cmH2O, Frequency = 6 Hz, I:E = 1:1. A sustained inflation (SI; 50 cmH2O for 60s followed by an incremental mean airway pressure (mPaw trial (steps of 3 cmH2O every 15 minutes were performed in both groups until PaO2 no longer increased. This was regarded as full lung inflation. The mPaw was decreased by 3 cmH2O and the animals reached the end of the study protocol. Gas exchange and hemodynamic data were collected at each step. Results The SI led to a significant improvement of the PaO2/FiO2-Index (HFOV: 200 ± 100 vs. PCV: 58 ± 15 and TAli: 57 ± 12; p 2-reduction (HFOV: 42 ± 5 vs. PCV: 62 ± 13 and TAli: 55 ± 9; p Ali: 6.1 ± 1 vs. T75: 3.4 ± 0.4; PCV: TAli: 6.7 ± 2.4 vs. T75: 4 ± 0.5; p Conclusion A sustained inflation followed by an incremental mean airway pressure trial in HFOV improved oxygenation at a lower mPaw than during conventional lung protective ventilation. HFOV but not PCV resulted in normocapnia, suggesting that during HFOV there are alternatives to tidal ventilation to achieve CO2-elimination in an "open lung" approach.

  15. Protective effects of valproic acid against airway hyperresponsiveness and airway remodeling in a mouse model of allergic airways disease.

    Science.gov (United States)

    Royce, Simon G; Dang, William; Ververis, Katherine; De Sampayo, Nishika; El-Osta, Assam; Tang, Mimi L K; Karagiannis, Tom C

    2011-12-01

    Airway remodeling and airway hyperresponsiveness are major aspects of asthma pathology that are not targeted optimally by existing anti-inflammatory drugs. Histone deacetylase inhibitors have a wide range of effects that may potentially abrogate aspects of remodeling. One such histone deacetylase inhibitor is valproic acid (2-propylvaleric acid). Valproic acid is used clinically as an anti-epileptic drug and is a potent inhibitor of class I histone deacetylases but also inhibits class II histone deacetylases. We used valproic acid as a molecular model of histone deacetylase inhibition in vivo in chronic allergic airways disease mice with airway remodeling and airway hyperresponsiveness. Wild-type Balb/c mice with allergic airways disease were treated with valproic acid or vehicle control. Airway inflammation was assessed by bronchoalveolar lavage fluid cell counts and examination of lung tissue sections. Remodeling was assessed by morphometric analysis of histochemically stained slides and lung function was assessed by invasive plethysmography measurement of airway resistance. Valproic acid treatment did not affect inflammation parameters; however, valproic acid treatment resulted in reduced epithelial thickness as compared to vehicle treated mice (p < 0.01), reduced subepithelial collagen deposition (p < 0.05) and attenuated airway hyperresponsiveness (p < 0.05 and p < 0.01 for the two highest doses of methacholine, respectively). These findings show that treatment with valproic acid can reduce structural airway remodeling changes and hyperresponsiveness, providing further evidence for the potential use of histone deacetylase inhibitors for the treatment of asthma.

  16. Airway stents

    Science.gov (United States)

    Keyes, Colleen

    2018-01-01

    Stents and tubes to maintain the patency of the airways are commonly used for malignant obstruction and are occasionally employed in benign disease. Malignant airway obstruction usually results from direct involvement of bronchogenic carcinoma, or by extension of carcinomas occurring in the esophagus or the thyroid. External compression from lymph nodes or metastatic disease from other organs can also cause central airway obstruction. Most malignant airway lesions are surgically inoperable due to advanced disease stage and require multimodality palliation, including stent placement. As with any other medical device, stents have significantly evolved over the last 50 years and deserve an in-depth understanding of their true capabilities and complications. Not every silicone stent is created equal and the same holds for metallic stents. Herein, we present an overview of the topic as well as some of the more practical and controversial issues surrounding airway stents. We also try to dispel the myths surrounding stent removal and their supposed use only in central airways. At the end, we come to the long-held conclusion that stents should not be used as first line treatment of choice, but after ruling out the possibility of curative surgical resection or repair. PMID:29707506

  17. The deflation limb of the pressure-volume relationship in infants during high-frequency ventilation.

    Science.gov (United States)

    Tingay, David G; Mills, John F; Morley, Colin J; Pellicano, Anastasia; Dargaville, Peter A

    2006-02-15

    The importance of applying high-frequency oscillatory ventilation with a high lung volume strategy in infants is well established. Currently, a lack of reliable methods for assessing lung volume limits clinicians' ability to achieve the optimum volume range. To map the pressure-volume relationship of the lung during high-frequency oscillatory ventilation in infants, to determine at what point ventilation is being applied clinically, and to describe the relationship between airway pressure, lung volume, and oxygenation. In 12 infants, a partial inflation limb and the deflation limb of the pressure-volume relationship were mapped using a quasi-static lung volume optimization maneuver. This involved stepwise airway pressure increments to total lung capacity, followed by decrements until the closing pressure of the lung was identified. Lung volume and oxygen saturation were recorded at each airway pressure. Lung volume was measured using respiratory inductive plethysmography. A distinct deflation limb could be mapped in each infant. Overall, oxygenation and lung volume were improved by applying ventilation on the deflation limb. Maximal lung volume and oxygenation occurred on the deflation limb at a mean airway pressure of 3 and 5 cm H(2)O below the airway pressure approximating total lung capacity, respectively. Using current ventilation strategies, all infants were being ventilated near the inflation limb. It is possible to delineate the deflation limb in infants receiving high-frequency oscillatory ventilation; in doing so, greater lung volume and oxygenation can be achieved, often at lower airway pressures.

  18. Electrical activity of the diaphragm during nCPAP and high flow nasal cannula

    NARCIS (Netherlands)

    de Waal, C. G.; Hutten, G. J.; Kraaijenga, J. V.; de Jongh, F. H.; van Kaam, A. H.

    2017-01-01

    Objective To determine if the electrical activity of the diaphragm, as measure of neural respiratory drive and breathing effort, changes over time in preterm infants transitioned from nasal continuous positive airway pressure (nCPAP) to high flow nasal cannula (HFNC). Design Prospective

  19. Acute effect of pure oxygen breathing on diabetic macular edema

    DEFF Research Database (Denmark)

    Vinten, Carl Martin; La Cour, Morten; Lund-Andersen, Henrik

    2012-01-01

    Purpose. A small-scale pilot study of the pathophysiology of diabetic macular edema (DME) was made by assessing concomitant changes in macular volume (MV), mean arterial blood pressure (MABP), intraocular pressure (IOP), retinal artery diameter (RAD), and retinal vein diameter (RVD) in response...... diameters by fundus photography, intraocular pressure by pulse-air tonometry, and arterial blood pressure by sphygmomanometry. Results. After initiation of pure oxygen breathing, reductions of 2.6% in RAD (p=0.04) and 11.5% reduction in RVD (p...

  20. Comparison of low- and ultralow-dose computed tomography protocols for quantitative lung and airway assessment.

    Science.gov (United States)

    Hammond, Emily; Sloan, Chelsea; Newell, John D; Sieren, Jered P; Saylor, Melissa; Vidal, Craig; Hogue, Shayna; De Stefano, Frank; Sieren, Alexa; Hoffman, Eric A; Sieren, Jessica C

    2017-09-01

    Quantitative computed tomography (CT) measures are increasingly being developed and used to characterize lung disease. With recent advances in CT technologies, we sought to evaluate the quantitative accuracy of lung imaging at low- and ultralow-radiation doses with the use of iterative reconstruction (IR), tube current modulation (TCM), and spectral shaping. We investigated the effect of five independent CT protocols reconstructed with IR on quantitative airway measures and global lung measures using an in vivo large animal model as a human subject surrogate. A control protocol was chosen (NIH-SPIROMICS + TCM) and five independent protocols investigating TCM, low- and ultralow-radiation dose, and spectral shaping. For all scans, quantitative global parenchymal measurements (mean, median and standard deviation of the parenchymal HU, along with measures of emphysema) and global airway measurements (number of segmented airways and pi10) were generated. In addition, selected individual airway measurements (minor and major inner diameter, wall thickness, inner and outer area, inner and outer perimeter, wall area fraction, and inner equivalent circle diameter) were evaluated. Comparisons were made between control and target protocols using difference and repeatability measures. Estimated CT volume dose index (CTDIvol) across all protocols ranged from 7.32 mGy to 0.32 mGy. Low- and ultralow-dose protocols required more manual editing and resolved fewer airway branches; yet, comparable pi10 whole lung measures were observed across all protocols. Similar trends in acquired parenchymal and airway measurements were observed across all protocols, with increased measurement differences using the ultralow-dose protocols. However, for small airways (1.9 ± 0.2 mm) and medium airways (5.7 ± 0.4 mm), the measurement differences across all protocols were comparable to the control protocol repeatability across breath holds. Diameters, wall thickness, wall area fraction

  1. Possible role of differential growth in airway wall remodeling in asthma

    KAUST Repository

    Moulton, D. E.

    2011-01-20

    Possible role of differential growth in airway wall remodeling in asthma. J Appl Physiol 110: 1003-1012, 2011. First published January 20, 2011; doi:10.1152/japplphysiol.00991.2010.- Airway remodeling in patients with chronic asthma is characterized by a thickening of the airway walls. It has been demonstrated in previous theoretical models that this change in thickness can have an important mechanical effect on the properties of the wall, in particular on the phenomenon of mucosal folding induced by smooth muscle contraction. In this paper, we present a model for mucosal folding of the airway in the context of growth. The airway is modeled as a bilayered cylindrical tube, with both geometric and material nonlinearities accounted for via the theory of finite elasticity. Growth is incorporated into the model through the theory of morphoelasticity. We explore a range of growth possibilities, allowing for anisotropic growth as well as different growth rates in each layer. Such nonuniform growth, referred to as differential growth, can change the properties of the material beyond geometrical changes through the generation of residual stresses. We demonstrate that differential growth can have a dramatic impact on mucosal folding, in particular on the critical pressure needed to induce folding, the buckling pattern, as well as airway narrowing. We conclude that growth may be an important component in airway remodeling. Copyright © 2011 the American Physiological Society.

  2. Comparison of trapezius squeeze test and jaw thrust as clinical indicators for laryngeal mask airway insertion in spontaneously breathing children

    Science.gov (United States)

    Dinesh Kumar, K. K.; Bhardwaj, Neerja; Yaddanapudi, Sandhya

    2017-01-01

    Background and Aims: It is not known whether trapezius squeeze test (TPZ) is a better clinical test than jaw thrust (JT) to assess laryngeal mask airway (LMA) insertion conditions in children under sevoflurane anesthesia. Material and Methods: After the Institutional Ethics Committee approval and written informed parental consent, 124 American Society of Anesthesiologists I and II children of 2–8 years of age undergoing minor surgical procedures were randomized into TPZ and JT groups. The children were induced with 8% sevoflurane in oxygen at a fresh gas flow of 4 L/min. TPZ or JT was performed after 1 min of start of sevoflurane and then every 20 s till the test was negative, when end-tidal (ET) sevoflurane concentration was noted. Classic LMA of requisite size was inserted by a blinded anesthetist and conditions at the insertion of LMA, insertion time, and the number of attempts of LMA insertion were recorded. Results: The mean LMA insertion time was significantly longer (P < 0.001) for TPZ (145 ± 28.7 sec) compared to JT group (111.8 ± 31.0 sec). ET sevoflurane concentration at the time of LMA insertion was comparable in the two groups. LMA insertion conditions were similar in the two groups. There was no difference between the two groups regarding total number of attempts of LMA insertion. Heart rate (HR) decreased in both groups after LMA insertion (P < 0.001) but TPZ group had significantly lower HR compared with the JT group up to 5 min after LMA insertion (P = 0.03). Conclusion: Both JT and TPZ are equivalent clinical indicators in predicting the optimal conditions of LMA insertion in spontaneously breathing children; however, it takes a longer time to achieve a negative TPZ squeeze test. PMID:28413275

  3. A randomized non-crossover study comparing the ProSeal and Classic laryngeal mask airway in anaesthetized children.

    Science.gov (United States)

    Lopez-Gil, M; Brimacombe, J; Garcia, G

    2005-12-01

    We tested the hypothesis that ease of insertion, oropharyngeal leak pressure, fibreoptic position, gastric insufflation, and the frequency of mucosal trauma differ between the ProSeal laryngeal mask airway (PLMA) and the classic laryngeal mask airway (cLMA) in anaesthetized children. For the PLMA, we also assessed the ease of gastric tube placement via the PLMA drain tube and measure residual gastric volume. 240 consecutive ASA I-III children aged 1-16 yr were randomized for airway management with the ProSeal or cLMA. The time taken to provide an effective airway, the number of insertion attempts, fibreoptic position of the airway tube and frequency of mucosal trauma were similar, but oropharyngeal leak pressure was higher (33 vs 26 cm H(2)O, Ptube insertion was successful at the first attempt in 106 of 120, and at the second attempt in 14 of 120. The mean (sd; range) value for residual gastric volume was 2.2 (5.9; 0-30) ml. There were no differences in performance among sizes for the PLMA and the cLMA. We conclude that ease of insertion, fibreoptic position, and frequency of mucosal trauma are similar for the PLMA and cLMA in children, but oropharyngeal leak pressure is higher and gastric insufflation less common for the PLMA. Gastric tube insertion has a high success rate, provided the PLMA is correctly positioned.

  4. Atopic asthmatic immune phenotypes associated with airway microbiota and airway obstruction.

    Directory of Open Access Journals (Sweden)

    Benjamin A Turturice

    Full Text Available Differences in asthma severity may be related to inflammation in the airways. The lower airway microbiota has been associated with clinical features such as airway obstruction, symptom control, and response to corticosteroids.To assess the relationship between local airway inflammation, severity of disease, and the lower airway microbiota in atopic asthmatics.A cohort of young adult, atopic asthmatics with intermittent or mild/moderate persistent symptoms (n = 13 were assessed via bronchoscopy, lavage, and spirometry. These individuals were compared to age matched non-asthmatic controls (n = 6 and to themselves after six weeks of treatment with fluticasone propionate (FP. Inflammation of the airways was assessed via a cytokine and chemokine panel. Lower airway microbiota composition was determined by metagenomic shotgun sequencing.Unsupervised clustering of cytokines and chemokines prior to treatment with FP identified two asthmatic phenotypes (AP, termed AP1 and AP2, with distinct bronchoalveolar lavage inflammatory profiles. AP2 was associated with more obstruction, compared to AP1. After treatment with FP reduced MIP-1β and TNF-α and increased IL-2 was observed. A module of highly correlated cytokines that include MIP-1β and TNF-α was identified that negatively correlated with pulmonary function. Independently, IL-2 was positively correlated with pulmonary function. The airway microbiome composition correlated with asthmatic phenotypes. AP2, prior to FP treatment, was enriched with Streptococcus pneumoniae. Unique associations between IL-2 or the cytokine module and the microbiota composition of the airways were observed in asthmatics subjects prior to treatment but not after or in controls.The underlying inflammation in atopic asthma is related to the composition of microbiota and is associated with severity of airway obstruction. Treatment with inhaled corticosteroids was associated with changes in the airway inflammatory response to

  5. Continuous Positive Airway Pressure Device Time to Procurement in a Disadvantaged Population

    Directory of Open Access Journals (Sweden)

    Lourdes M. DelRosso

    2015-01-01

    Full Text Available Introduction. The management of obstructive sleep apnea (OSA in patients who cannot afford a continuous positive airway pressure (CPAP device is challenging. In this study we compare time to CPAP procurement in three groups of patients diagnosed with OSA: uninsured subsidized by a humanitarian grant (Group 1, uninsured unsubsidized (Group 2, and those with Medicare or Medicaid (Group 3. We evaluate follow-up and adherence in Group 1. We hypothesize that additional factors, rather than just the ability to obtain CPAP, may uniquely affect follow-up and adherence in uninsured patients. Methods. 30 patients were in Groups 1 and 2, respectively. 12 patients were in Group 3. Time of CPAP procurement from OSA diagnosis to CPAP initiation was assessed in all groups. CPAP adherence data was collected for Group 1 patients at 1, 3, 6, and 9 months. Results. There were no significant differences between groups in gender, age, body mass index, or apnea hypopnea index. The mean time to procurement in Group 1 was shorter compared to Group 2 but not significant. Compared to both Group 1 and Group 2, Group 3 patients had significantly shorter times to device procurement. Conclusion. Time to procurement of CPAP was significantly shorter in those with Medicaid/Medicare insurance compared to the uninsured.

  6. Supra-Epiglottic Upper Airway Volume in Elderly Patients with Obstructive Sleep Apnea Hypopnea Syndrome.

    Science.gov (United States)

    Boutet, Claire; Abdirahman Mohamed Moussa, Syad; Celle, Sébastien; Laurent, Bernard; Barthélémy, Jean-Claude; Barral, Fabrice-Guy; Roche, Frédéric

    2016-01-01

    Small upper airway measurements areas and high body mass index are recognized risk factors for obstructive sleep apnea syndrome (OSAS) in non-elderly populations; however, there is limited information regarding elderly patients. We evaluated whether upper airway volume is associated with OSAS and OSAS treated with continuous positive airway pressure (CPAP) treatment and whether BMI is correlated with upper airway volume and measurements in elderly subjects. In 60 volunteers aged 75.58±0.9 years: 20 OSAS, 20 OSAS chronically treated with CPAP, and 20 controls, semi-automatic segmentation, retropalatal distance and transverse diameter of the supra-epiglottic upper airway were evaluated using 3DT1-weighted magnetic resonance imaging. Anteroposterior to transverse diameter ratio was defined as retropalatar diameter/transverse diameter. There were no significant differences in supra-epiglottic upper airway volume between OSAS, CPAP treated patients, and controls. There were significant differences in retropalatal distance and anteroposterior to transverse diameter ratio between OSAS, CPAP treated patients, and controls (P = 0.008 and Psupra-epiglottic upper airway volume. In elderly subjects, OSAS and body mass index are not associated with changes in supra-epiglottic upper airway volume but are associated with modification of pharynx shape.

  7. Prevention of Hypoxemia During Apnea Testing: A Comparison of Oxygen Insufflation And Continuous Positive Airway Pressure.

    Science.gov (United States)

    Kramer, Andreas H; Couillard, Philippe; Bader, Ryan; Dhillon, Peter; Kutsogiannis, Demetrios J; Doig, Christopher J

    2017-08-01

    Apnea testing is an essential step in the clinical diagnosis of brain death. Current international guidelines recommend placement of an oxygen (O 2 ) insufflation catheter into the endotracheal tube to prevent hypoxemia, but use of a continuous positive airway pressure (CPAP) valve may be more effective at limiting arterial partial pressure of O 2 (PO 2 ) reduction. We performed a multicenter study assessing consecutive apnea tests in 14 intensive care units (ICUs) in two cities utilizing differing protocols. In one city, O 2 catheters are placed and arterial blood gases (ABGs) performed at intervals determined by the attending physician. In the other city, a resuscitation bag with CPAP valve is attached to the endotracheal tube, and ABGs performed every 3-5 min. We assessed arterial PO 2 , partial pressure of carbon dioxide (PCO 2 ), pH, and blood pressure at the beginning and termination of each apnea test. Thirty-six apnea tests were performed using an O 2 catheter and 50 with a CPAP valve. One test per group was aborted because of physiological instability. There were no significant differences in the degree of PO 2 reduction (-59 vs. -32 mmHg, p = 0.72), rate of PCO 2 rise (3.2 vs. 3.9 mmHg per min, p = 0.22), or pH decline (-0.02 vs. -0.03 per min, p = 0.06). Performance of ABGs at regular intervals was associated with shorter test duration (10 vs. 7 min, p pressure decline (p = 0.006). Both methods of O 2 supplementation are associated with similar changes in arterial PO 2 and PCO 2 . Performance of ABGs at regular intervals shortens apnea test duration and may avoid excessive pH reduction and consequent hemodynamic effects.

  8. Design, characterization and use of replicate human upper airways for radon dosimetry studies

    International Nuclear Information System (INIS)

    Swift, D.L.; Cheng, Y.S.; Su, Y.F.; Yeh, H.C.

    1992-01-01

    The size distribution of inhaled radon progeny aerosols is a significant factor in dosimetry. The role of the airways above the trachea is an important determinant of the respiratory distribution of both attached and unattached progeny aerosols. In order to provide information on the effect of particle size and breathing conditions on the overall and local deposition, we have developed a method to produce a replicate airway model from an in vivo magnetic resonance imaging coronal scan. The model consists of a sandwich of methacrylate elements, each element having the thickness of the scan interval. The transition between successive scan outlines traced on the front and back surfaces of each element is handsculpted in the plastic. The hollow model of the nasal passages thus produced has been characterized both morphologically and fluid-mechanically and has a flow resistance typical of a normal adult. The model has several distinct advantages for studies of radon progeny aerosol deposition. After exposure to a radioaerosol (or to an aerosol of an otherwise measurable substance) the individual elements can be separated to determine local deposition. The dimensions of specific upper-airway regions can be changed by replacing a small number of elements. The model has been incorporated in an exposure system for determining overall nandregional