ImportanceSurgical site infections (SSIs)—especially anastomotic dehiscence—are major contributors to morbidity and mortality after rectal resection. The role of mechanical and oral antibiotics bowel preparation (MOABP) in preventing complications of rectal resection is currently disputed.ObjectiveTo assess whether MOABP reduces overall complications and SSIs after elective rectal resection compared with mechanical bowel preparation (MBP) plus placebo.Design, Setting, and ParticipantsThis multicenter, double-blind, placebo-controlled randomized clinical trial was conducted at 3 university hospitals in Finland between March 18, 2020, and October 10, 2022. Patients aged 18 years and older undergoing elective resection with primary anastomosis of a rectal tumor 15 cm or less from the anal verge on magnetic resonance imaging were eligible for inclusion. Outcomes were analyzed using a modified intention-to-treat principle, which included all patients who were randomly allocated to and underwent elective rectal resection with an anastomosis.InterventionsPatients were stratified according to tumor distance from the anal verge and neoadjuvant treatment given and randomized in a 1:1 ratio to receive MOABP with an oral regimen of neomycin and metronidazole (n = 277) or MBP plus matching placebo tablets (n = 288). All study medications were taken the day before surgery, and all patients received intravenous antibiotics approximately 30 minutes before surgery.Main Outcomes and MeasuresThe primary outcome was overall cumulative postoperative complications measured using the Comprehensive Complication Index. Key secondary outcomes were SSI and anastomotic dehiscence within 30 days after surgery.ResultsIn all, 565 patients were included in the analysis, with 288 in the MBP plus placebo group (median [IQR] age, 69 [62-74] years; 190 males [66.0%]) and 277 in the MOABP group (median [IQR] age, 70 [62-75] years; 158 males [57.0%]). Patients in the MOABP group experienced fewer overall postoperative complications (median [IQR] Comprehensive Complication Index, 0 [0-8.66] vs 8.66 [0-20.92]; Wilcoxon effect size, 0.146; P < .001), fewer SSIs (23 patients [8.3%] vs 48 patients [16.7%]; odds ratio, 0.45 [95% CI, 0.27-0.77]), and fewer anastomotic dehiscences (16 patients [5.8%] vs 39 patients [13.5%]; odds ratio, 0.39 [95% CI, 0.21-0.72]) compared with patients in the MBP plus placebo group.Conclusions and RelevanceFindings of this randomized clinical trial indicate that MOABP reduced overall postoperative complications as well as rates of SSIs and anastomotic dehiscences in patients undergoing elective rectal resection compared with MBP plus placebo. Based on these findings, MOABP should be considered as standard treatment in patients undergoing elective rectal resection.Trial RegistrationClinicalTrials.gov Identifier: NCT04281667

中文翻译：

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直肠切除前机械肠道准备和口服抗生素后的发病率

重要性手术部位感染（SSIs）——尤其是吻合口裂开——是直肠切除术后发病率和死亡率的主要原因。机械和口服抗生素肠道准备（MOABP）在预防直肠切除术后并发症中的作用目前存在争议。目的评估与机械肠道准备（MBP）加安慰剂相比，MOABP 是否可以减少择期直肠切除术后的总体并发症和 SSI。这项多中心、双盲、安慰剂对照随机临床试验于 2020 年 3 月 18 日至 2022 年 10 月 10 日在芬兰 3 所大学医院进行。 18 岁及以上接受直肠肿瘤一期吻合选择性切除术的患者磁共振成像中距离肛门边缘 15 厘米或更小的区域符合纳入条件。使用改良的意向治疗原则对结果进行分析，其中包括所有被随机分配并接受择期直肠切除吻合术的患者。 干预措施根据肿瘤距肛缘的距离和新辅助治疗的情况对患者进行分层按 1:1 的比例接受 MOABP 联合新霉素和甲硝唑口服方案 (n = 277) 或 MBP 加匹配的安慰剂片剂 (n = 288)。所有研究药物均在手术前一天服用，所有患者在手术前约 30 分钟接受静脉注射抗生素。 主要结果和措施 主要结果是使用综合并发症指数测量的总体累积术后并发症。关键的次要结局是术后 30 天内的 SSI 和吻合口裂开。 结果 分析中总共纳入了 565 名患者，其中 288 名患者属于 MBP 加安慰剂组（中位 [IQR] 年龄，69 [62-74] 岁；190 名男性[66.0%]），MOABP 组有 277 名（中位 [IQR] 年龄，70 [62-75] 岁；158 名男性 [57.0%]）。 MOABP 组患者的总体术后并发症较少（中位 [IQR] 综合并发症指数为 0 [0-8.66] vs 8.66 [0-20.92]；Wilcoxon 效应大小为 0.146；磷< .001），较少的 SSI（23 名患者 [8.3%] vs 48 名患者 [16.7%]；比值比，0.45 [95% CI，0.27-0.77]），以及更少的吻合口裂开（16 名患者 [5.8%] vs 39 名患者） [13.5%]；比值比，0.39 [95% CI，0.21-0.72]）与 MBP 加安慰剂组的患者相比。结论和相关性 这项随机临床试验的结果表明，MOABP 降低了总体术后并发症以及 SSI 发生率与 MBP 加安慰剂相比，接受选择性直肠切除术的患者出现吻合口裂开的情况。基于这些发现，MOABP 应被视为接受择期直肠切除术的患者的标准治疗。试验注册ClinicalTrials.gov 标识符：NCT04281667