Mechanical bowel preparation (MBP) is common practice in elective colorectal surgery. In recent literature the value of MBP is subject of discussion. We conducted a multicenter, randomized study with the goal of comparing outcome of elective colorectal resections and primary anastomoses with and without mechanical bowel preparation in terms of anastomotic leakage and other septic complications.

Within the setting of a multicenter randomized trial,1433 patients were randomized before elective colorectal surgery to receive either MBP or to have no MBP but a normal meal on the day before operation. The primary endpoint was anastomotic leakage. Secondary endpoints were septic complications (wound infection, urinary infection, pneumonia, pelvic abscesses), fascia dehiscence and death.

The incidence of anastomotic leakage was similar in both groups: 5.1% in patients without MBP versus 4.9% in patients with MBP (p=0.93; 95% confidence interval for the difference (no MBP minus MBP) ranges from –2.3% tot +2.7%). There were no significant differences in other septic complications, fascia dehiscence, or mortality. Fecal contamination, number of days until resumption of a normal diet, and duration of hospital stay were similar in both groups.

This study shows that elective colorectal surgery can be safely done without MBP. Therefore, MBP should be abandoned in elective colorectal surgery.

Inclusion Criteria:

The main inclusion criterion was elective colorectal surgery with primary anastomosis

Exclusion Criteria:

Exclusion criteria were an acute laparotomy, laparoscopic colorectal surgery, contraindications for the use of mechanical bowel preparation, an a priori deviating (ileo) stoma, and age less than 18 years old.