Preoperative intensive inspiratory muscle training to prevent postoperative pulmonary complications in high-risk patients undergoing CABG surgery:A randomized clinical trial

Abstract

Context:Postoperative pulmonary complications(PPCs)after coronary artery bypass graft(CABG)surgery are a major source of morbidity and mortality,and increase length of hospital stay and resource utilization.The prehospitalization period before CABG surgery may be used to improve a patient's pulmonary condition.The efficacy of preoperative inspiratory muscle training(IMT)in reducing the incidence of PPCs in high-risk patients undergoing CABG surgery has not yet been determined.Objective:To evaluate the prophylactic efficacy of preoperative IMT on the incidence of PPCs in high-risk patients scheduled for elective CABG surgery.Design,Setting,and Patients:A single-blind,randomized clinical trial conducted at the University Medical Center Utrecht,Utrecht,the Netherlands,with enrollment between July 2002 and August 2005.Of 655 patients referred for elective CABG surgery,299(45.6%)met criteria for high risk of developing PPCs,of whom 279 were enrolled and followed up until discharge from hospital.Intervention:Patients were randomly assigned to receive either preoperative IMT(n=140)or usual care(n=139).Both groups received the same postoperative physical therapy.Main Outcome Measures:Incidence of PPCs,especially pneumonia,and duration of postoperative hospitalization.Results:Both groups were comparable at baseline.After CABG surgery,PPCs were present in 25(18.0%)of 139 patients in the IMT group and 48(35.0%)of 137 patients in the usual care group(odds ratio [OR],0.52;95%confidence interval [CI],0.30-0.92).Pneumonia occurred in 9(6.5%)of 139 patients in the IMT group and in 22(16.1%)of 137 patients in the usual care group(OR,0.40;95%CI,0.19-0.84).Median duration of postoperative hospitalization was 7 days(range,5-41 days)in the IMT group vs 8 days(range,6-70 days)in the usual care group by Mann-Whitney U statistic(z=-2.42;P=.02).Conclusion:Preoperative IMT reduced the incidence of PPCs and duration of postoperative hospitalization in patients at high risk of developing a pulmonary complication undergoing CABG surgery.