To the Editor:
We read with interest the article by Urbach, Kennedy, and Cohen. 1 Clearly, the number of patients with drainage after colorectal anastomosis was low in the four articles analyzed. As expressed in their conclusions, however, we would like to add two more large, well-designed randomized controlled trials 2,3 focusing on drainage after colorectal anastomoses, which were not available when the authors did their meta-analysis. These should give further credibility to their conclusions.
When the 809 patients in these two trials are added to the 414 patients in the four other studies, one notes that they become responsible for at least 50% of the weight. Realizing that summarizing all the information in these six trials into a single odds ratio may lead to oversimplification, 4 the overall (Peto) odds ratio for mortality drops from 1.38 to 0.98, clearly supporting the idea that drainage after elective colorectal anastomoses do not affect mortality. Additionally, the odds ratio for radiologic fistula remains practically the same (1.01 to 0.92), but that for wound complications drops from 1.70 to 1.20, weakening slightly the risk of deleterious effects of drainage on wound complications. The risk for respiratory complications also remains the same, but the risk of clinical fistula increased from 1.47 to 1.80 (with a nearly statistically significant OR (IC = 0.94–3.46), reinforcing the idea that drainage may actually increase the rate of (clinical) leakage.
Our conclusions remain: neither pelvic nor abdominal drainage is needed after anastomosis in elective, uncomplicated, colorectal surgery.
August 30, 1999
Abe Fingerhut MD, FACS, FRCS
Simon Msika MD, PhD
Elie Yahchouchi MD
Fethi Mérad MD
Jean-Marie Hay MD
Bertrand Millat MD
French Association for Clinical Research
References
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