Background: The use of the incentive spirometry (IS) with expiratory positive airway pressure (EPAP) to prevent postoperative pulmonary complications (PPC) after coronary artery bypass graft (CABG) is not well established. This study sought to determine the effects of IS+EPAP after CABG.
Methods: Thirty-four patients undergoing CABG were randomly assigned to a control group or IS+EPAP group. Maximal respiratory pressures, pulmonary function test, 6-minute walk test and chest x-ray were performed at baseline as well as 1 week and 1 month after CABG.
Results: Maximal inspiratory pressure was significantly higher in the IS+EPAP group compared to controls at both 1 week and 1 month (P<.001). Maximal expiratory pressure was significantly higher at 1 month compared to 1 week in IS+EPAP group (P<.01). At 1 month, forced vital capacity and forced expiratory volume in 1 second was significantly higher in IS+EPAP compared to controls (P<.05). Inspiratory capacity was higher at 1 month in IS+EPAP group compared to controls (P<.05). The distance walked in 6-minute walk test was higher at 1 month in IS+EPAP group (P<.001) compared to controls. Lastly, radiological injury score at 1 week was lower in IS+EPAP compared to controls (P<.004).
Conclusions: In patients undergoing CABG, IS+EPAP results in improved pulmonary function and 6-minute walk distance as well as a reduction in PPC.