Feasibility and Reliability of Functional Muscle Tests in Lung Transplant Recipients

Objective This study investigates the feasibility, reliability, and correlations of recommended functional tests in lung transplant recipients shortly after surgery. Design This is an observational study. Methods Fifty patients (28 females) performed well-standardized maximum isometric back extension in a sitting position, handgrip strength, and Biering-SOrensen endurance tests shortly before discharge from the acute hospital, shortly thereafter, and 2 mos later after subacute rehabilitation. Results Back extension testing was well feasible, but only two thirds of the patients could perform the Biering-SOrensen test at baseline and they experienced a greater number of minor but no major adverse events. Absolute reliability measures and the intraclass correlation coefficients were excellent for the strength (0.97-0.98 [0.95-0.99]) and good for the endurance tests (0.69 [0.26-0.87]). Handgrip revealed high correlation with back strength (0.75) but not with Biering-SOrensen scores. Conclusions Well-controlled maximum back strength testing is feasible and reliable, and the scores are highly correlated with grip strength in lung transplant recipients shortly before hospital discharge. The Biering-SOrensen test should be limited to patients without dominant weakness and/or fear. Future research should investigate whether grip instead of back extension strength can safely be used for proper exercise prescription.