Negative Pressure Wound Management in Perineal Wound Status Post Abdominoperineal Resection and Extralevator Abdominoperineal Excision : A Meta-analysis and Trial sequential analysis

Purpose: Recent evidence-based publications disclosed that negative pressure wound therapy (NPWT) may reduce the incidence rate of surgical site infection and length of hospital stay compared with conventional drainage in patient status post abdominoperineal resection (APR) and extralevator abdominoperineal excision (ELAPE). Methods: : Data sources: Eligible randomized controlled trials, retrospective and prospective studies published before June 2021 were retrieved from databases(Cochrane Library, PubMed, and Embase). Study selection: (a) the study involved patients undergoing ELAPE or APR with postoperative NPWT; (b) the study compared NWPT with conventional drainage and reported at least one outcome of interest (i.e., SSI); and (c) the study provided adequate information to calculate the effect estimated for meta-analysis. Interventions: We calculated the odds ratio (ORs) and mean differences (MDs) with 95% confidence intervals (CIs). Main outcome measures: The measure outcomes included SSI and LOS. Results: : Eight articles, involving 547 patients, met the selection criteria. Compared to conventional drainage, NPWT was associated with a significantly lower SSI rate (fixed-effect, OR 0.29; 95% CI 0.18–0.45; I 2 = 0%) in eight studies and 547 patients. Besides, NPWT was associated with a shorter LOS (fixed-effect, MD −2.00; CI −2.60 to −1.39; I 2 = 0%) than conventional drainage in three studies and 305 patients. In a trial sequential analysis, the cumulative number of patients in the analyses of both outcomes exceeded the required information size and surpassed the significance boundary in favor of NPWT, suggesting conclusive results. Conclusion: NPWT is superior to conventional drainage in both SSI rate and LOS, and the statistical power of SSI and LOS are confirmed by trial sequential analysis.