Since the publication of several European guidelines,1–3 new information has become available regarding the role of mechanical bowel preparation (MBP) in reducing surgical site infection associated with colorectal surgery, and our guidelines have acknowledged that new information. When these European guidelines were published, they relied heavily on a Cochrane review from 2011,4 which included no data after 2010. In fact, the Cochrane review also acknowledged the need for more data, specifically stating, “Further research on mechanical bowel preparation or enemas versus no preparation in patients submitted for elective rectal surgery and laparoscopic colorectal surgery is warranted.4”
In our review of the data available up to 2016,5 we found that there is now new evidence from a meta-analysis (including 1769 randomly assigned patients)6 in favor of mechanical bowel preparation plus oral antibiotic bowel preparation. Although the letter to the editor written by Slim and Kartheuser refers to this new data as a “systematic review,” it is actually a meta-analysis of randomized trials and should be acknowledged as a high-level source of evidence. In addition to randomized trials, multiple large, retrospective observational studies7–11 from diverse populations of patients support our recommendation, thus explaining the grade 2B level of recommendation.
In 2016, the World Health Organization, in its global guidelines for the prevention of surgical site infection,12 also independently made the same recommendation as we did and characterized the current evidence as moderate quality, just as we did. The American College of Surgeons and Surgical Infection Society also published a similar recommendation in 2016.13 The discrepancy between the previous European guidelines and the guidelines of the World Health Organization, American College of Surgeons, and Surgical Infection Society is attributed to new evidence, and it is interesting that, in the face of the new evidence, Slim and Kartheuser state, “…the European recommendation is not to be revisited at present.”
Finally, Slim and Kartheuser refer to our guideline as “the present American recommendation,” and we request that they refer to this guideline as the North American recommendation, because several of our authors reside and practice medicine in our neighboring country, Canada.