Comparative Effectiveness of Positive Expiratory Pressure Therapy versus Incentive Spirometry on Postoperative Pulmonary Function and Complications following Cardiopulmonary Surgery: Systematic Review and Meta-Analysis

Background: Postoperative pulmonary complications are a significant issue in the aftermath of cardiopulmonary surgery, which often causes a rise in morbidity and prolonged hospitalization. Objective: To compare the effectiveness of Positive Expiratory Pressure therapy and Incentive Spirometry on pulmonary function and postoperative pulmonary complications in patients undergoing cardiopulmonary surgery. Methodology: This study systematically collates and synthesizes the findings of various randomized controlled trials. The meta-analytic method enables the combination of existing evidence, enhancing statistical power and providing a comprehensive evaluation of the interventions’ impacts. Some electronic databases, such as PubMed, Google Scholar, Cochrane Library, and Semantic, were used to conduct the literature search to identify controlled trials published between 2010 and 2024 among adult patients with postoperative cardiopulmonary complications. Results of all the included studies were analyzed, and the meta-analysis was conducted by Review Manager, and the Cochrane Risk of Bias 2 tool was used to evaluate the risk of bias of the included controlled trials bases of its five domains. Peer-reviewed studies containing a relevant outcome measure were included, whereas duplicates, non-English articles, studies with insufficient outcome data measures, or irrelevant procedures were not. Results: A total of 155 studies were identified, of which 141 were screened after duplicate removal. Title and abstract screening yielded nine full-text articles, and five studies met the eligibility criteria. The meta-analysis showed low-level evidence supporting Positive Expiratory Pressure therapy, with a statistically significant improvement in oxygen saturation compared to Incentive Spirometry (SMD=1.47; 95% CI: 0.07-2.87; p=0.004). However, no significant difference was found for peak expiratory flow rate, with high heterogeneity (I²=95%) and a non-significant pooled effect size (SMD=1.15; p=0.37), indicating no clear advantage of either intervention for PEFR. Conclusion: Positive Expiratory Pressure therapy is associated with significant improvement in oxygen saturation compared to Incentive Spirometry, while no significant difference was observed. Both therapies demonstrated comparable effectiveness, with heterogeneous and limited evidence.