RT Journal Article
SR Electronic
T1 Physiological techniques for detecting expiratory flow limitation during tidal breathing
JF European Respiratory Review
JO EUROPEAN RESPIRATORY REVIEW
FD European Respiratory Society
SP 147
OP 155
DO 10.1183/09059180.00001911
VO 20
IS 121
A1 N.G. Koulouris
A1 G. Hardavella
YR 2011
UL http://err.ersjournals.com/content/20/121/147.abstract
AB 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.