Combined Mechanical and Oral Antibiotic Bowel Preparation Reduces Incisional Surgical Site Infection and Anastomotic Leak Rates After Elective Colorectal Resection An Analysis of Colectomy-Targeted ACS NSQIP

Objective: To determine the association between preoperative bowel preparation and 30-day outcomes after elective colorectal resection. Methods: Patients from the 2012 Colectomy-Targeted American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database who underwent elective colorectal resection were included for analysis and assigned to 1 of 4 groups based on the type of preoperative preparation they received [combined mechanical and oral antibiotic preparation (OAP), mechanical preparation only, OAP only, or no preoperative bowel preparation]. The association between preoperative bowel preparation status and 30-day postoperative outcomes was assessed using multivariate regression analysis to adjust for a robust array of patient- and procedure-related factors. Results: A total of 4999 patients were included for this study [1494 received (29.9%) combined mechanical and OAP, 2322 (46.5%) received mechanical preparation only, 91 (1.8%) received OAP only, and 1092 (21.8%) received no preoperative preparation]. Compared to patients receiving no preoperative preparation, patients who received combined preparation demonstrated a lower 30-day incidence of postoperative incisional surgical site infection (3.2% vs 9.0%, P < 0.001), anastomotic leakage (2.8% vs 5.7%, P = 0.001), and procedure-related hospital readmission (5.5% vs 8.0%, P = 0.03). The outcomes of patients who received either mechanical or OAP alone did not differ significantly from those who received no preparation. Conclusions: Combined bowel preparation with mechanical cleansing and oral antibiotics results in a significantly lower incidence of incisional surgical site infection, anastomotic leakage, and hospital readmission when compared to no preoperative bowel preparation.