RT Journal Article
SR Electronic
T1 Relevance of six-minute walk parameters in predicting pulmonary gas transfer
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P2193
VO 44
IS Suppl 58
A1 Muhammad Irfaan Khan
A1 Steve Scholey
YR 2014
UL http://erj.ersjournals.com/content/44/Suppl_58/P2193.abstract
AB BackgroundGas Transfer (GT) is routinely used in the assessment of ventilatory function. This study evaluates the predictive power of six minute walk (6MW) for the estimation of gas transfer, where there are issues with technical reliability or test performance.Aim To identify the strongest 6MW predictors of GT, and determine if ATS/ERS disease classification altered predictor significance.MethodsTechnically reliable, same-day lung function and 6MW results were compared in clinically stable patients (n=84), using the same pulmonary function equipment and 6MW track. Oxygen and short acting bronchodilators had been withheld prior to testing following intervention cessation guidelines. Disease classifications were based on ATS/ERS interpretation strategies. Voluntary consent and ethics submission were required.Results46 males and 38 females, aged 68 (SD = 10.1), BMI 30.6 (SD = 5.8) performed same day gas transfer and 6MW. Study included 43 obstructive, 19 restrictive, 16 mixed, and 6 normal individuals. Co-linearity adjusted multiple regression identified a predictive model based on distance walked (DW), BMI, gender, age, recovery time, lowest oxygen saturation, and total time walked (P< 0.01). DW (0.64), BMI and gender significantly correlated with actual GT (mmol/kPa/min) (R2 = 0.65), while only DW and BMI predicted gas exchange impairment and transfer coefficient. Disease classification did not affect the significance of predictor variables, although 6MWD was a greater predictor for patients with obstructive disease (0.82, R2 = 0.72).Conclusion6MW may be used to estimate GT, DW being the most important variable, with greater relevance in obstructive patients.