HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:
Guest Access | Sign In via User Name/Password

This Article Full Text (PDF) Free All Versions of this Article: chest.07-0062v1 chest.07-0062v2 132/2/471    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to My Personal Article Archive Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Walker, R. Articles by Holland, A. E Search for Related Content PubMed PubMed Citation Articles by Walker, R. Articles by Holland, A. E

REPRODUCIBILITY OF THE NEGATIVE EXPIRATORY PRESSURE TECHNIQUE IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE

¹School of Physiotherapy, La Trobe University, Melbourne, Australia 3086 ²Anaesthesiology and Critical Care, University of Queensland, Australia 4072; and ³Physiotherapy Department, The Alfred Hospital, Melbourne, Australia 3004

a.holland{at}alfred.org.au

Abstract

BackgroundTidal expiratory flow limitation (EFL) contributes to chronic dyspnoea and exercise intolerance in chronic obstructive pulmonary disease (COPD). It can be assessed with the Negative Expiratory Pressure (NEP) technique and expressed as either the percentage of the tidal volume over which EFL occurs (EFL%V_T) or according to more detailed three-point or five-point scoring systems. The aim of this study was to evaluate the reproducibility of the NEP technique in COPD.

MethodsTidal EFL was evaluated with NEP in 18 subjects with stable COPD (FEV₁ range 18-75% predicted) on two occasions (mean re-test interval 8.2 days) by the same rater. Agreement between testing occasions was assessed with the kappa statistic for the three-point & five-point EFL scores, & with the coefficient of repeatability for EFL%V_T.

ResultsOn the first testing occasion, nine subjects had no EFL, four subjects had EFL in supine, & five subjects had EFL in sitting & supine. Using the three-point score, agreement was present in 14/18 subjects at time two (kappa=0.66), indicating substantial agreement. Using the five-point score, agreement was seen in 13/18 subjects (kappa=0.61), also indicating substantial agreement. The reproducibility of EFL%V_T measurements was lower than that required to reliably detect clinical change in both sitting and supine (coefficient of repeatability 37% and 58% respectively).

ConclusionsThe three-point and five-point scores provide a reproducible assessment of EFL in COPD. Classification of EFL as a percentage of tidal volume is less reproducible and large changes are required to be confident that real clinical change has occurred.

Key Words: Pulmonary disease • chronic obstructive • Respiratory function tests • Reproducibility of results