The effects of inspiratory muscle training on exercise capacity, dyspnea and lung functions in lung transplantation candidates

Abstract

Background: This study was planned with the consideration that Inspiratory Muscle Training (IMT) would contribute to the improvement of exercise capacity, dyspnea perception and lung functions by increasing respiratory muscle strength. Methods: This was designed as a prospective, randomized, double-blind study, and included 34 LTx candidates. The patients were randomly divided into two groups (PR plus IMT Group=PRIMT; Standard PR Group=SPR). All patients underwent a 3-month hospital based PR with or without IMT. Study outcomes: exercise capacity (6MWD), respiratory muscle strength (MIP, MEP), dyspnea perception (mMRC), Pulmonary Functions (FEV1, FVC, DLCO, DLCO/VA). Results: It was found that PRIMT group had much more significant increase in 6MWD (104m, p=0,03) and MIP (p=0,001) than the SPR group. Although both groups demonstrated a statistically significant decrease in the mMRC dyspnea score, no significant differences were found between the groups (p = 0.075). In all pulmonary functions, there was a slight increase in the PRIMT group (not statistically significant) and a decrease tendency in the SPR group after treatment. When comparing the delta values of the groups, a significant difference was found in favor of the PRIMT in DLCO / VA (%) (p = 0.02). Conclusion: A greater increase in exercise capacity and respiratory muscle strength was observed in the PRIMT group. The normally expected decline in respiratory function due to advanced lung disease was prevented. Our study showed that the IMT increased the benefits provided by PR. These gains obtained in the preoperative period will also be an advantage in the postoperative period.