Practice Patterns and Outcomes of Preoperative Mechanical Bowel Preparation and Oral Antibiotics for Restorative Elective Colorectal Surgery: Nationwide Analysis of the ACS-NSQIP Australian Data

Abstract

There is increasing evidence that the addition of preoperative antibiotics (OAB) reduces infectious complications after colorectal surgery. To understand practice patterns in Australia, Australian hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) collecting targeted colectomy and proctectomy data were collated. Adult patients who had elective restorative colectomy or proctectomy between January 2015 and November 2023. Eight hundred thirty-nine patients were included. Mechanical bowel preparation (MBP) alone was the most common strategy for segmental colectomy (42.46%) and proctectomy (75%). The rate of MBP and oral antibiotics (OAB) remained low (11.7% to 25.3% between 2019 and 2023). This was associated with a decline in superficial SSI (11.7% to 4%) over this time. When the cohort was divided into three groups: MBP+/OAB+ (n = 143), MBP+/OAB- (n = 458) and MBP-/OAB- (n = 238), there were no statistical differences in infectious complications between the groups. However, the MBP+/OAB+ group had the lowest superficial surgical site infection (SSI) rate in the laparoscopic (5.3%) and open surgery (9.2%) subgroups. This was associated with a significant reduction in the odds ratio (OR) 0.52 (95% CI 0.27-1.01) of developing any SSI and a reduced length of stay in the open subgroup. Despite recommendations by several international guidelines, level 1 evidence from meta-analyses and network meta-analyses as well as a Cochrane review that MBP and OAB reduce infectious complications, there remains a low uptake of MBP and OAB in major colorectal surgery at major NSQIP hospitals in Australia, with even lower uptake in smaller non-NSQIP hospitals.