Objective: To determine the prophylactic efficacy of short-term intensive preoperative inspiratory muscle training on the incidence of postoperative pulmonary complications in patients scheduled for cardiac surgery. Design: Single-blind, randomized controlled pilot study. Setting: TEDA International Cardiovascular Hospital, China. Subjects: In total, 197 subjects aged ⩾50 years scheduled for cardiac surgery were selected. Intervention: The intervention group ( n = 98) received five days of preoperative inspiratory muscle training on top of the usual care received by the patients in the control group ( n = 99). Main measures: The primary outcome variable was the occurrence of postoperative pulmonary complications. The secondary outcome variables were inspiratory muscle strength, lung function and length of hospitalization. Results: After cardiac surgery, a total of 10 (10.2%) of the 98 patients in the intervention group and 27 (27.3%) of 99 patients in the control group had postoperative pulmonary complications (risk ratio, 0.23; 95% confidence interval (CI), 0.09–0.58, P = 0.002). The study revealed that, compared with the control group, the intervention group had a significant increase in inspiratory muscle strength (by 10.48 cm H2O, P < 0.001), forced expiratory volume in the first second of expiration (FEV1) %predicted (by 3.75%, P = 0.030), forced vital capacity (FVC) %predicted (by 4.15%, P = 0.008) and maximal voluntary ventilation (MVV) %predicted (by 6.44%, P = 0.034). Length of hospital stay was 7.51 (2.83) days in the intervention group and 9.38 (3.10) days in the control group ( P = 0.039). Conclusion: A five-day intensive pattern of preoperative inspiratory muscle training reduced the incidence of postoperative pulmonary complications and duration of postoperative hospitalization in patients undergoing cardiac surgery.
Inspiratory muscle training for reducing postoperative pulmonary complications: A simple method but short of data?