Background: Mechanical bowel preparation before colectomy is controversial for several reasons, including a theoretically increased risk of Clostridium difficile infection.
Objective: The primary aim of this study was to compare the incidence of C difficile infection among patients who underwent mechanical bowel preparation and those who did not. A secondary objective was to assess the association between C difficile infection and the use of oral antibiotics.
Design: This was an observational cohort study.
Setting: The Michigan Surgical Quality Collaborative Colectomy Project (n = 24 hospitals) participates in the American College of Surgeons-National Surgical Quality Improvement Program with additional targeted data specific to patients undergoing colectomies.
Patients: Included were adult patients (21 years and older) admitted to participating hospitals for elective colectomy between August 2007 and June 2009.
Main outcome measure: The main outcome measure was laboratory detection of a positive C difficile toxin assay or stool culture.
Results: Two thousand two hundred sixty-three patients underwent colectomy and fulfilled inclusion criteria. Fifty-four patients developed a C difficile infection, for a hospital median rate of 2.8% (range, 0-14.7%). Use of mechanical bowel preparation was not associated with an increased incidence of C difficile infection (P = .95). Among 1685 patients that received mechanical bowel preparation, 684 (41%) received oral antibiotics. The proportion of patients in whom C difficile infection was diagnosed after the use of preoperative oral antibiotics was smaller than the proportion of patients with C difficile infection who did not receive oral antibiotics (1.6% vs 2.9%, P = .09).
Limitations: The potential exists for underestimation of C difficile infection because of the study's strict data collection criteria and risk of undetected infection after postoperative day 30.
Conclusions: In contrast to previous single-center data, this multicenter study showed that the preoperative use of mechanical bowel preparation was not associated with increased risk of C difficile infection after colectomy. Moreover, the addition of oral antibiotics with mechanical bowel preparation did not confer any additional risk of infection.