Objective To investigate whether oral antimicrobial prophylaxis as an adjunct to intravenous antibiotic prophylaxis reduces surgical site infections after elective colorectal surgery. Design Multicentre, randomised, double blind, placebo controlled trial. Setting 11 university and non-university hospitals in France between 25 May 2016 and 8 August 2019. Participants 926 adults scheduled for elective colorectal surgery. Intervention Patients were randomised to receive either a single 1 g dose of ornidazole (n=463) or placebo (n=463) orally 12 hours before surgery, in addition to intravenous antimicrobial prophylaxis before surgical incision. Main outcome measures The primary outcome was the proportion of patients with surgical site infection within 30 days after surgery. Secondary outcomes included individual types of surgical site infections and major postoperative complications (Clavien-Dindo classification grade 3 or higher) within 30 days after surgery. Results Of the 960 patients who were enrolled, 926 (96%) were included in the analysis. The mean age of participants was 63 years and 554 (60%) were men. Surgical site infection within 30 days after surgery occurred in 60 of 463 patients (13%) in the oral prophylaxis group and 100 of 463 (22%) in the placebo group (absolute difference −8.6%, 95% confidence interval −13.5% to −3.8%; relative risk 0.60, 95% confidence interval 0.45 to 0.80). The proportion of patients with deep infections was 4.8% in the oral prophylaxis group and 8.0% in the placebo group (absolute difference −3.2%, 95% confidence interval −6.4% to −0.1%). The proportion of patients with organ space infections was 5.0% in the oral prophylaxis group and 8.4% in the placebo group (absolute difference −3.4%, −6.7% to −0.2%). Major postoperative complications occurred in 9.1% patients in the oral prophylaxis group and 13.6% in the placebo group (absolute difference −4.5%, −8.6% to −0.5%). Conclusion Among adults undergoing elective colorectal surgery, the addition of a single 1 g dose of ornidazole compared with placebo before surgery significantly reduced surgical site infections. Trial registration ClinicalTrials.gov [NCT02618720][1]. Deidentified data about the individual participants will be shared with researchers of further studies on reasonable request. Request for data sharing will be handled in line with the data access and sharing policy of Clermont-Ferrand University Hospital. [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02618720&atom=%2Fbmj%2F379%2Fbmj-2022-071476.atom

中文翻译：

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口服抗菌药物预防对择期结直肠手术后手术部位感染的影响：多中心、随机、双盲、安慰剂对照试验

目的探讨口服抗菌药物预防作为静脉抗生素预防的辅助手段是否可以减少择期结直肠手术后的手术部位感染。设计多中心、随机、双盲、安慰剂对照试验。2016 年 5 月 25 日至 2019 年 8 月 8 日期间在法国设置了 11 家大学和非大学医院。参与者 926 名成年人计划进行择期结直肠手术。干预 患者在手术前 12 小时随机接受单剂量 1 g 奥硝唑（n=463）或安慰剂（n=463）口服，此外在手术切口前进行静脉内抗菌预防。主要结果测量 主要结果是术后 30 天内发生手术部位感染的患者比例。次要结局包括手术后 30 天内各种类型的手术部位感染和主要术后并发症（Clavien-Dindo 分级 3 级或更高）。结果 在入组的 960 名患者中，926 名 (96%) 被纳入分析。参与者的平均年龄为 63 岁，其中 554 人（60%）为男性。口服预防组 463 名患者中有 60 名（13%）和安慰剂组 463 名患者中有 100 名（22%）在术后 30 天内发生手术部位感染（绝对差异 -8.6%，95% 置信区间 -13.5% 至−3.8%；相对风险 0.60，95% 置信区间 0.45 至 0.80）。口服预防组深部感染患者的比例为 4.8%，安慰剂组为 8.0%（绝对差异 -3.2%，95% 置信区间 -6.4% 至 -0.1%）。口服预防组发生器官间隙感染的患者比例为 5.0%，安慰剂组为 8.4%（绝对差异为 -3.4%，-6.7% 至 -0.2%）。口服预防组 9.1% 的患者和安慰剂组 13.6% 的患者发生了主要的术后并发症（绝对差异为 -4.5%，-8.6% 至 -0.5%）。结论 在接受择期结直肠手术的成年人中，与安慰剂相比，术前加用 1 g 奥硝唑可显着减少手术部位感染。试验注册 ClinicalTrials.gov [NCT02618720][1]。应合理要求，将与进一步研究的研究人员共享有关个人参与者的去识别化数据。数据共享请求将根据克莱蒙费朗大学医院的数据访问和共享政策进行处理。[1]：