Prophylactic postoperative noninvasive ventilation in adults undergoing upper abdominal surgery: A systematic review and meta-analysis

Objectives: Postoperative pulmonary complications (PPCs) are a leading cause of morbidity and mortality following upper abdominal surgery. Applying either noninvasive ventilation (NIV) or continuous positive airway pressure (CPAP) in the early postoperative period is suggested to prevent PPC. We aimed to assess whether postoperative NIV or CPAP or both prevent PPCs compared with standard care in adults undergoing upper abdominal surgery, including in those identified at higher PPC risk. Additionally, the different interventions used were evaluated to assess whether there is a superior approach.Data sources: We searched PubMed, Embase' CINAHL, CENTRAL, and Scopus from inception to May 17, 2021.Study selection: We performed a systematic search of the literature for randomized controlled trials evaluating prophylactic NIV and/or CPAP in the postoperative period.Data extraction: Two authors independently performed study selection and data extraction. Individual study risk of bias was assessed using the PEDro scale, and certainty in outcomes was assessed using the Grading of Recommendations Assessment, Development, and Evaluation framework.Data synthesis: We included 17 studies enrolling 6,108 patients. No significant benefit was demonstrated for postoperative NIV/CPAP to reduce PPC (risk ratio [RR], 0.89; 95% CI, 0.78-1.01; very low certainty), including in adults identified at higher PPC risk (RR, 0.91; 95% CI, 0.77-1.07; very low certainty). No intervention approach was identified as superior, and no significant benefit was demonstrated when comparing: 1) CPAP (RR, 0.90; 95% CI, 0.79-1.04; very low certainty), 2) NIV (RR, 0.68; 95% CI, 0.41-1.13; very low certainty), 3) continuous NIV/CPAP (RR, 0.90; 95% CI, 0.77-1.05; very low certainty), or 4) intermittent NIV/CPAP (RR, 0.66; 95% CI, 0.39-1.10; very low certainty) to standard care.Conclusions: These findings suggest routine provision of either prophylactic NIV or CPAP following upper abdominal surgery may not be effective to reduce PPCs' including in those identified at higher risk