Use of bowel preparation does not reduce postoperative infectious morbidity following minimally invasive or open hysterectomies

Background: Literature on the use of bowel preparation in gynecologic surgery is scarce and limited to minimally invasive gynecologic surgery. The decision on the use of bowel preparation before benign or malignant hysterectomies is mostly driven by extrapolating data from the colorectal literature. Objective: Bowel preparation is a controversial element within enhanced recovery protocols, and literature investigating its efficacy in gynecologic surgery is scarce. Our aim was to determine if mechanical bowel preparation alone, oral antibiotics alone, or a combination are associated with decreased rates of surgical site infections or anastomotic leaks compared to no bowel preparation following benign or malignant hysterectomy. Study Design: We identified women who underwent hysterectomy between January 2006 and July 2017 using OptumLabs, a large US commercial health plan database. Inverse propensity score weighting was used separately for benign and malignant groups to balance baseline characteristics. Primary outcomes of 30-day surgical site infection, anastomotic leaks, and major morbidity were assessed using multivariate logistic regression that adjusted for race, census region, household income, diabetes, and other unbalanced variables following propensity score weighting. Results: A total of 224,687 hysterectomies (benign, 186,148; malignant, 38,539) were identified. Median age was 45 years for the benign and 54 years for the malignant cohort. Surgical approach was as follows: benign: laparoscopic/robotic, 27.2%; laparotomy, 32.6%; vaginal, 40.2%; malignant: laparoscopic/robotic, 28.8%; laparotomy, 47.7%; vaginal, 23.5%. Bowel resection was performed in 0.4% of the benign and 2.8% of the malignant cohort. Type of bowel preparation was as follows: benign: none, 93.8%; mechanical bowel preparation only, 4.6%; oral antibiotics only, 1.1%; mechanical bowel preparation with oral antibiotics, 0.5%; malignant: none, 87.2%; mechanical bowel preparation only, 9.6%; oral antibiotics only, 1.8%; mechanical bowel preparation with oral antibiotics, 1.4%. Use of bowel preparation did not decrease rates of surgical site infections, anastomotic leaks, or major morbidity following benign or malignant hysterectomy. Among malignant abdominal hysterectomies, there was no difference in the rates of infectious morbidity between mechanical bowel preparation alone, oral antibiotics alone, or mechanical bowel preparation with oral antibiotics, compared to no preparation. Conclusion: Bowel preparation does not protect against surgical site infections or major morbidity following benign or malignant hysterectomy, regardless of surgical approach, and may be safely omitted.