Weaning from mechanical ventilation in COPD patients: interest to measure, in post-extubation, the airway occlusion pressure (P0.1), in order to indicate non-invasive pressure support ventilation (NIPSV) to prevent relapse

Aim: To compare pressure support versus T-piece trial for weaning from mechanical ventilation Methodology: Randomized clinical trial in Surgical ICU, Khyber Teaching hospital Peshawar. 48 patients who had been mechanically ventilated for at least 24 hours and were deemed suitable for weaning took part in the study. SBT with pressure support ventilation of 8cm of H2O was performed on one group of patients for two hours while the other group received a 30-minute SBT with pressure support ventilation. It was successful when extubation process is completed, (being able to go 72 hours without mechanical ventilation after the first SBT). Results: Extubation was successful in 83.3% who received pressure support ventilation and in 75% who employed a T-piece. The patients who required reintubation were 12% with support pressure and 16.7% with T piece ventilation. Mortality rate in support pressure group is 16.7% while 25% in T piece ventilation group. Conclusion: Pressure support ventilation for 30 minutes had a much higher success rate when it came to extubation. For spontaneous breathing trials, a shorter, less taxing ventilation approach should be used rather than the traditional one. Keywords: Extubation, Support pressure, T piece

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To assess the predictive value of the respiratory mode, automatic tube compensation, in the process of weaning from mechanical ventilation compared to another mode, namely pressure support ventilation

http://isrctn.org/> ◽

10.1186/isrctn16080446 ◽

2012 ◽

Author(s):

Jonathan Cohen

Keyword(s):

Mechanical Ventilation ◽

Pressure Support Ventilation ◽

Predictive Value ◽

Pressure Support ◽

Weaning From Mechanical Ventilation ◽

Support Ventilation ◽

Tube Compensation

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Respiratory muscle pressure analysis in pressure-support ventilation

Journal of Applied Physiology ◽

10.1152/jappl.1994.77.5.2237 ◽

1994 ◽

Vol 77 (5) ◽

pp. 2237-2243 ◽

Cited By ~ 19

Author(s):

Y. Yamada ◽

M. Shigeta ◽

K. Suwa ◽

K. Hanaoka

Keyword(s):

Pressure Support Ventilation ◽

Respiratory Muscle ◽

Pressure Support ◽

Respiratory Muscles ◽

Random Order ◽

Support Ventilation ◽

Airway Occlusion ◽

Airway Opening ◽

Airway Occlusion Pressure ◽

Inspiratory Work

The extent to which respiratory muscles are exerted during partially supported ventilation is difficult to differentiate, because these muscles and the ventilator work simultaneously to produce ventilation. We have developed a new method for determining the pressure developed by the respiratory muscles in partially supported ventilation. In seven patients on pressure-support ventilation (PSV), pressure, flow, and lung volume change were measured at the airway opening. Various PSV levels (0–15 cmH2O) were applied to each patient in random order. By utilizing a model of respiratory mechanics, we calculated the pressure developed by the respiratory muscles and the inspiratory work performed by the muscles from the measured parameters by use of the resistance and elastance of the respiratory system obtained during controlled ventilation. Increasing PSV from 0 to 15 cmH2O modulated the resultant breathing pattern, i.e., increasing tidal volume and decreasing respiratory rate. The respiratory muscle pressure, although less negative, had a shape that corresponded to the shape of airway occlusion pressure at each PSV level, and both pressures decreased concomitantly with increasing PSV. The respiratory muscle work progressively decreased with increasing PSV. This analysis enabled clear and continuous quantifications of the respiratory muscle force generation and inspiratory work during partially supported ventilation.

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Inspiratory muscle workload due to dynamic intrinsic PEEP in stable COPD patients: effects of two different settings of non-invasive pressure-support ventilation

Monaldi Archives for Chest Disease ◽

10.4081/monaldi.2004.704 ◽

2004 ◽

Vol 61 (2) ◽

Cited By ~ 6

Author(s):

M. Vitacca ◽

B. Lanini ◽

S. Nava ◽

L. Barbano ◽

R. Porta ◽

...

Keyword(s):

Pressure Support Ventilation ◽

Pressure Support ◽

Inspiratory Muscle ◽

Intrinsic Peep ◽

Transdiaphragmatic Pressure ◽

Support Ventilation ◽

Non Invasive ◽

Rehabilitation Centers ◽

Copd Patients ◽

Randomised Controlled

Background: In severe stable hypercapnic COPD patients the amount of pressure time product (PTP) spent to counterbalance their dynamic intrinsic positive end expiratory pressure (PEEPi,dyn) is high: no data are available on the best setting of non invasive pressure support ventilation (NPSV) to reduce the inspiratory muscle workload due to PEEPi,dyn. Methods: The objectives of this randomised controlled physiological study were: 1. To measure the inspiratory muscle workload due to PEEPi,dyn 2. To measure the effects on this parameter of two settings of NPSV in stable COPD patients with chronic hypercapnia admitted in a Pulmonary Division of two Rehabilitation Centers. Twenty- three stable COPD patients with chronic hypercapnia on domiciliary nocturnal NPSV for 30±20 months were submitted to an evaluation of breathing pattern, PEEPi,dyn, inspiratory muscle workload and its partitioning during both assisted and unassisted ventilation. Two settings of NPSV were randomly applied for 30 minutes each: i- “at patient’s comfort” (C): Inspiratory pressure support (IPS) was the maximal tolerated pressure able to reduce awake PaCO2 with the addition of a pre-set level of external PEEP (PEEPe); ii- “physiological setting” (PH): the level of IPS able to achieve a > 40% and < 90% decrease in transdiaphragmatic pressure in comparison to spontaneous breathing (SB). A PEEPe level able to reduce PEEPi,dyn by at least 50% was added. Results: During SB the tidal diaphragmatic pressuretime product (PTPdi/b) was 17.62±7.22 cmH2O*sec, the component due to PEEPi,dyn (PTPdiPEEPi,dyn) being 38 ± 17% (range: 16-65%). Compared to SB, PTPdiPEEPi,dyn was reduced significantly with both settings, the reduction being greater with PH compared to C. Conclusions: In conclusion in severe COPD patients with chronic hypercapnia the inspiratory muscle workload due to PEEPidyn is high and is reduced by NPSV at a greater extent when ventilator setting is tailored to patient’s mechanics.

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