RT Journal Article
SR Electronic
T1 Noninvasive detection of positive end-expiratory pressure in COPD patients recovering from acute respiratory failure
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP PA3565
DO 10.1183/13993003.congress-2016.PA3565
VO 48
IS suppl 60
A1 Lara Pisani
A1 Emanuele Bernardi
A1 Luca Fasano
A1 Marco Ferrari
A1 Nadia Corcione
A1 Francesco Tosello
A1 Elisa Pizzolato
A1 Bruno Tartaglino
A1 Stefano Nava
YR 2016
UL http://erj.ersjournals.com/content/48/suppl_60/PA3565.abstract
AB The detection of intrinsic Positive End-Expiratory Pressure (PEEPi) is one of the main clinical challenge in patients with COPD, since it requires the insertion of gastro-esophageal balloons, to record the changes of transdiaphragmatic pressure (PdiPEEPi) and flow.In this study we aimed to record the PEEPi, using a noninvasive method, comparing it with PdiPEEPi. We recorded a total of 84 measures in 7 COPD patients recovering from an episode of acute hypercapnic respiratory failure requiring mechanical ventilation. In the first part of the study we tested the hypothesys that subtle change from linear to granular pattern of diaphragm-liver interface, during M-mode echography was due to the start of diaphragm contraction. When compared to the start of the Pdi rise (i.e.indication of beginning of diaphragm contraction) the difference between the two we recording was 2.5+1.3 ms. Subsequently we measured with the echographyc method the presence of PEEPi (echoPEEPI) using the following equation:echo PEEPi= P0.1 x Tlat/100 where P0.1=mouth occlusion pressure at 100ms,Tlat= echography time latency between diaphragm contraction and onset of inspiratory flow.P0.1 was used for measuring the slope of the pressure signal to estimate the effort the patients must overcome to generate inspiratory flow. The Bland and Altman plot showed a bias of only -0,3 cmH20, between PdiPEEPi and ecoPEEPi, with estimated limits of agreement +1.1 and -1.6 cmH20 and a high interoperator concordance (interclass correlation coefficient=0.98, CI95% 0.97-0.99). We described for the first time the good agreement between an invasive recording of PEEPi and a noninvasive one.