Intra-Cavity Lavage and Wound Irrigation for Prevention of Surgical Site Infection: Systematic Review and Network Meta-Analysis.

Surgical site infections (SSIs) are costly and associated with poorer patient outcomes. Intra-operative surgical site irrigation and intra-cavity lavage may reduce the risk of SSIs through removal of dead or damaged tissue, metabolic waste, and site exudate. Irrigation with antibiotic or antiseptic solutions may further reduce the risk of SSI because of bacteriocidal properties. Randomized controlled trials (RCTs) have been conducted comparing irrigation solutions, but important comparisons (e.g., antibiotic vs. antiseptic irrigation) are absent. We use systematic review-based network meta-analysis (NMA) of RCTs to compare irrigation solutions for prevention of SSI. We used Cochrane methodology and included all RCTs of participants undergoing a surgical procedure with primary site closure, in which method of irrigation was the only systematic difference between groups. We used a random effects Bayesian NMA to create a connected network of comparisons. Results are presented as odds ratios (OR) of SSI, where OR <1 indicates a beneficial effect. We identified 42 eligible RCTs with 11,726 participants. Most were at unclear or high risk of bias. The RCTs included groups given no irrigation or non-antibacterial, antiseptic, or antibiotic irrigation. There was substantial heterogeneity, and a random effects model was selected. Relative to non-antibacterial irrigation, mean OR of SSI was 0.439 (95% credible interval: 0.282, 0.667) for antibiotic irrigation and 0.573 (0.321, 0.953) for antiseptic agents. No irrigation was similar to non-antibacterial irrigation (OR 0.959 [0.555, 1.660]). Antibiotic and antiseptic irrigation were ranked as most effective for preventing SSIs; this conclusion was robust to potential bias. Our NMA found that antibiotic and antiseptic irrigation had the lowest odds of SSI. There was high heterogeneity, however, and studies were at high risk of bias. A large RCT directly comparing antibiotic irrigation with both antiseptic and non-antibacterial irrigation is needed to define the standard of care for SSI prevention by site irrigation.