Mechanical and oral antibiotics bowel preparation reduce the risk of surgical site infections and anastomotic leakage in colorectal surgery: a GRADE-based meta-analysis and trial sequential analysis

The study analyzed 17 randomized controlled trials with a total of 4,633 patients comparing mechanical and oral antibiotic bowel preparation (MOABP) with mechanical bowel preparation (MBP) alone in colorectal surgery. A meta-analysis showed that MOABP significantly reduces the risk of postoperative surgical site infections (SSI) with OR = 0.44 (95% CI: 0.37–0.54, p < 0.00001, I² = 33%, moderate-quality evidence). It also reduces the risk of anastomotic leak (AL) with OR = 0.42 (95% CI: 0.30–0.50, moderate quality of evidence). Subgroup analyzes confirmed a reduction in superficial SSI, deep SSI, space and organ infection. Test sequence analysis (TSA) verified the robustness of these results. The authors concluded that MOABP reduces the risk of SSI and AL in colorectal surgery and recommend considering the addition of oral antibiotics to preoperative bowel preparation.