目的 明确结肠、直肠切除吻合术前常规机械性肠道准备（mechanical bowel preparation, MBP）的安全性和有效性。方法 检索2008年1月以前MEDLINE、EMBASE、Cochrane Library、Cochrane协作网随机对照试验注册数据库、中国期刊全文数据库（CNKI）等数据库，纳入相关随机对照试验进行系统评价和Meta分析。结果 纳入12个随机对照试验共4992例结肠、直肠切除吻合病例。分析发现，MBP组与无MBP组在病死率［RR为1.02，95%CI （0.64，1.59），P=0.95］、吻合口漏发生率［RR值为1.16，95%CI（0.86，1.55），P=0.33］、再手术率［RR值为1.05，95%CI（0.81，1.35），P=0.71］、切口感染率［RR值为1.17，95%CI （0.98，1.40），P=0.08］和腹腔脓肿发生率［RR值为0.93，95%CI（0.60，1.45），P=0.75］等方面的差异无统计学意义。结论 结肠、直肠切除吻合术前无需常规进行机械性肠道准备。

Mechanical bowel preparation before elective colorectal surgery: a systematic review of global randomized clinical trials PANG Ming-hui, LUO Bin, ZHANG Wei, et al. Department of Gastroenterology，Sichuan Provincial Peoples’ Hospital, Chengdu 610072,China Corresponding author: ZHANG Wei, E-mail: donald zhang65@yahoo.com.cn Abstract Objective To investigate the safety and effectiveness of routine preoperational mechanical bowel preparation (MBP) in patients with colorectal anastomosis. Methods A global electronic and hand searching were carried to identify randomized clinical trials. After quality assessment of all included RCTs, meta-ananysis was performed with Review Manager 4.2.7. Results 12 RCTs with 4992 patients were included. When comparing MBP with None MBP group, the differences in mortality［RR 1.02，95%CI（0.64，1.59），P=0.95］, ananstomotic dehiscence［RR 为1.16，95%CI （0.86，1.55），P=0.33］, reoperation rate［RR 为1.05，95%CI （0.81，1.35），P=0.71］, wound infection［RR 为1.17，95%CI （0.98，1.40），P=0.08］and abdominal abscess ［RR 0.93，95%CI（0.60，1.45），P=0.75］ were of no significance. Conclusion we advise that mechanical bowel preparation before elective colorectal surgery can safely be abandoned.