Antimicrobial prophylaxis for colorectal surgery

  • Review
  • Intervention




Research shows that administration of prophylactic antibiotics before colorectal surgery prevents postoperative surgical wound infection (SWI). The best antibiotic choice, timing of administration and route of administration remain undetermined.


To establish the effectiveness of antimicrobial prophylaxis for the prevention of SWI in patients undergoing colorectal surgery: specifically to determine,
1 Whether it reduces risk of SWI.
2 The target spectrum/a of bacteria (aerobic and/or anaerobic).
3 The best timing and duration of antibiotic administration.
4 The most effective route of antibiotic administration (intravenous, oral or both).
5 Whether any antibiotic is clearly more effective than the currently recommended gold standard.

Search methods

CENTRAL, MEDLINE, and EMBASE, were searched from January, 1980 to December, 2007.

Selection criteria

Randomised controlled trials of prophylactic antibiotic use in elective and emergency colorectal surgery, with SWI as an outcome.

Data collection and analysis

Data were abstracted and reviewed by three authors for only the single, dichotomous outcome of SWI. 

Main results

The review included 182 trials (30,880 participants), and 50 different antibiotics, including 17 cephalosporins. Many studies had multiple variables that separated the two study groups and could not be compared to other studies that tested one antibiotic and had a single variable separating the two groups.
Meta-analyses demonstrated a statistically significant difference in postoperative SWI when prophylactic antibiotics were compared to placebo/no treatment (relative risk (RR) 0.30, 95% confidence intervals (CI) 0.22 to 0.41). No statistically significant differences were shown when comparing short- and long-term duration of prophylaxis (RR 1.06, 95% CI 0.89 to 1.27); or single dose versus multiple dose antibiotics (RR 1.17, 95% CI 0.67 to 2.05). Additional aerobic coverage and additional anaerobic coverage both showed statistically significant improvements in SWI rates (RR 0.41, 95% CI 0.23 to 0.71 and RR 0.55, 95% CI 0.35 to 0.85, respectively); as did combined oral and intravenous antibiotic prophylaxis when compared to intravenous alone (RR 0.55, 95% CI 0.41 to 0.74), or oral alone (RR 0.34, 95% CI 0.13 to 0.87).
Established gold standard regimens were no less effective than any other antibiotic choice.

Authors' conclusions

Antibiotics covering aerobic and aerobic bacteria should be delivered orally and intravenously prior to colorectal surgery.  Antibiotics delivered within this framework will reduce the risk of postoperative SWI by at least 75%.  Further research is required to establish the optimal timing and duration of dosing, and frequency of longer-term adverse effects such as Clostridium difficile pseudomembranous colitis.




研究顯示使用預防性抗生素於大腸直腸外科手術可預防術後傷口感染(surgical wound infection, SWI)。抗生素的選擇,其使用時機,以及使用的路徑仍無明確定論。




搜尋1980年一月至2007年十二月的 CENTRAL、MEDLINE、與EMBASE之文獻資料庫。






這次的分析包括182篇試驗(共包含30,880參與者),比較50種不同抗生素,其中包含17種頭孢菌素。許多文獻涵蓋多種變數,比較兩組病人的預後;這些文獻無法與其他使用一種抗生素,比較單一變數之文獻互相比較。我們使用統合分析(metaanalysis)結果顯示:手術後傷口感染在於使用預防性抗生素組別,相對於使用安慰劑/沒有接受治療之組別,在統計學上有顯著差異(相對危險度0.30,95% 信賴區間 0.22 – 0.4)。術後傷口感染在統計上並沒有顯著的不同,包括長期使用與短期使用預防性抗生素的組別(相對危險度 1.06,95%信賴區間 0.89 – 1.27),或是單一劑量與多次劑量的預防性抗生素使用(相對危險度 1.17,95%信賴區間 0.67 – 2.05)。附加涵蓋嗜氧及附加涵蓋厭氧效果的抗生素之給予,在改善術後傷口感染率上,有統計學顯著差異(分別的相對危險度0.41,95%信賴區間0.23 – 0.71;及相對危險度0.55,95%信賴區間0.35 – 0.85)。結合使用口服及經靜脈給予抗生素,相比較單純使用一種途徑之抗生素組別,在改善術後傷口感染率上,亦有統計學上差異(靜脈:相對危險度0.55,95%信賴區間0.41 – 0.74,口服:相對危險度0.34,95%信賴區間0.13 – 0.87)。 此分析顯示,公認之黃金標準預防性用藥在術後傷口之預防效果,不比其他任何抗生素差。





此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。



Plain language summary

Antibiotics need to be administered to patients prior to colorectal surgery

Abdominal surgical wound infection (SWI) in patients having operations on the large intestine occurs in about 40% of patients if antibiotics are not given. This risk can be greatly diminished by the administration of antibiotics prophylactically before surgery. This review determined the best choice of antibiotic type, and the way in which they should be administered by analysing 182 randomised controlled trials. The antibiotic(s) given must cover both aerobic and anaerobic bacteria, be given only once before surgery, and, because of current recommendations concerning colonic cleansing before surgery, should probably be given intravenously.