Background: Prophylactic negative-pressure wound therapy (pNPWT) may prevent surgical site infection (SSI) after laparotomy, but existing meta-analyses pooling only high-quality evidence have failed to confirm this effect. Recently, several randomized controlled trials (RCTs) have been published. We performed an updated systematic review and meta-analysis to determine if pNPWT reduces the incidence of SSI after laparotomy.

Methods: MEDLINE, Embase, CENTRAL and Web of Science were searched on the 25.08.2021 for RCTs reporting on the incidence of SSI in patients who underwent laparotomy with and without pNPWT. The systematic review was compliant with the AMSTAR2 recommendation and registered into PROSPERO. Risk ratios (RR) for SSI in patients with pNPWT, and risk difference (RD) between control and pNPWT patients, were obtained using random effects models. Heterogeneity was quantified using the I² value, and investigated using subgroup analyses, funnel plots and bubble plots. Risk of bias of included RCTs was assessed using the RoB2 tool.

Results: Eleven RCTs were included, representing 973 patients who received pNPWT and 970 patients who received standard wound dressing. Pooled RR and RD between patients with and without pNPWT were of, respectively, 0.665 (95% CI 0.49–0.91, I²: 38.7%, p = 0.0098) and −0.07 (95% CI −0.12 to −0.03, I²: 53.6%, p = 0.0018), therefore demonstrating that pNPWT decreases the incidence of SSI after laparotomy. Investigation of source of heterogeneity identified a potential small-study effect.

Conclusion: The protective effect of pNPWT against SSI after laparotomy is confirmed by high-quality pooled evidence.