Antibiotic Versus Saline Irrigation During Open Appendectomy: A Systematic Review, Meta-Analysis, and Trial Sequential Analysis of Randomized Controlled Trials

Why clinicians should know about it

• Picked for Microbiology (medical) (top studies of the week, 6 September 2026): High-quality evidence in a top journal

Abstract

BACKGROUND: Surgical site infection (SSI) is a common complication after open appendectomy. The effectiveness of intra-operative antibiotic irrigation compared with saline irrigation remains uncertain. To evaluate the efficacy and safety of antibiotic irrigation versus saline irrigation during open appendectomy. METHODS: We conducted a systematic review and random-effects meta-analysis of randomized controlled trials comparing antibiotic irrigation with saline irrigation in patients undergoing open appendectomy. The literature search identified 40 records; after duplicate removal and title/abstract screening, 15 articles underwent full-text review, and five randomized controlled trials (RCTs) were included. Risk of bias was assessed using the ROB-2 tool. RESULTS: Five RCTs involving 1,080 patients were included (533 antibiotic irrigation; 547 saline), conducted in Saudi Arabia, Egypt, Iran, Iraq, and Nepal. The weighted mean age was 28.20 years, and most participants were male (54.4% vs. 57.5% in intervention and control groups). The mean follow-up was 1.1 months. All trials were rated low risk of bias. SSI occurred in 4.8% (26/533) of patients receiving antibiotic irrigation versus 8.9% (49/547) receiving saline. Antibiotic irrigation significantly reduced SSI risk (RR 0.60, 95% CI: 0.36 to 0.99; p = 0.05) with minimal heterogeneity (I2 = 6.87%). Leave-one-out analyses suggested fragility, with significance not consistently maintained when individual studies were omitted. Trial sequential analysis crossed the conventional boundary but not the monitoring boundary, and the required information size was not reached, indicating inconclusive evidence. Doi plot analysis showed minor asymmetry (LFK index -1.90). No significant differences were observed for abdominal abscess, post-operative ileus, length of stay, or operative duration. CONCLUSIONS: Antibiotic irrigation may reduce SSI after open appendectomy, but the evidence is fragile and remains insufficient by TSA. Future research should focus on minimally invasive appendectomy, with open-surgery studies reserved for settings where it remains common.

Abstract as published, via PubMed.