Mechanical bowel preparation with pre-operative oral antibiotics in elective colorectal resections: an Australian...

Anastomotic leaks (AL) and surgical site infections (SSI) are serious complications after colorectal resection. Studies have shown the benefits of pre-operative oral antibiotics (OAB) with mechanical bowel preparation (MBP) in reducing AL and SSI rates. We aim to investigate our experience with the short-term outcomes of AL and SSI following elective colorectal resections in patients receiving OAB with MBP versus MBP only.

A retrospective analysis was performed from our database for patients who underwent elective colorectal resection between January 2019 and November 2021. Prior to August 2020, OAB was not used as part of MBP. After 2020, Neomycin and Metronidazole were used in conjunction with MBP. We evaluated differences in AL and SSI between both groups.

Five hundred and seventeen patients were included from our database with 247 having MBP while 270 had OAB and MBP. There was a significantly lower rate of AL in patients receiving MBP and OAB as compared to MBP alone (0.4% versus 3.0%, P-value = 0.03). The SSI rate at our institution was 4.4%. It was lower in patients with MBP and OAB as compared to MBP alone, but this was not clinically significant (3.3% versus 5.7%, P-value = 0.19).

The association in the reduction of AL with the addition of OAB to the MBP protocol seen here reinforces the need for future randomized controlled trials in the Australasian context. We recommend colorectal institutions in Australian and New Zealand consider OAB with MBP as part of their elective colorectal resection protocol.