C.E. Paterson1, P. Singh1, A.G. Hill1 1South Auckland Clinical School, Auckland, New Zealand
Introduction: The use of routine mechanical bowel preparation and oral antibiotics prior to elective colorectal resection is controversial. Recent evidence suggests that mechanical and oral antibiotics significantly reduce surgical site infections. However, there is a lack of consensus among international guidelines. Colorectal surgeons in Australasia were last surveyed on this topic in 2019. This study aimed to investigate how practice has changed in Australasia over the last 5 years.
Methods: A cross-sectional survey was distributed via e-mail to members of the Colorectal Surgical Society of Australia and New Zealand in June 2024. Results were anonymous and informed consent was taken upon submission of the survey. Data was collected on basic demographics, current practices on mechanical bowel preparation, oral antibiotics and probiotics. Statistical analysis was performed using R version 4.4.1.
Results: A total of 103 of 356 (29%) members submitted full responses. The mean age was 49 years, and 82% identified as male. Twenty-three percent of participants were from New Zealand, and 85% of participants worked at a tertiary centre. The median number of annual colonic resections was 50, and rectal resections was 15. For right sided colonic resections, 43% were using no preparation, 33% were using mechanical bowel preparation alone, 22% were using mechanical bowel preparation and oral antibiotics, and 2% were using oral antibiotics alone. For left sided colonic resections, 18% were using no preparation, 55% were using mechanical bowel preparation alone, 26% were using mechanical bowel preparation and oral antibiotics, and 1% were using oral antibiotics alone. For rectal resections, 2% were using no preparation, 71% were using mechanical bowel preparation alone, 27% were using mechanical bowel preparation and oral antibiotics, and 0% were using oral antibiotics alone. The most common combination of oral antibiotics was neomycin and metronidazole, and neomycin was only selected by Australian members. 15% of members recommended probiotics to their patients.
Conclusion: Routine use of mechanical bowel preparation and oral antibiotics has increased in New Zealand and Australia over the past five years. Neomycin and metronidazole was the most common oral antibiotic combination. Neomycin is not currently available in New Zealand, and this requires further consideration. A small proportion of members are recommending probiotics to their patients. Future research should analyse whether surgical site infection rates have decreased following the increased uptake of mechanical bowel preparation and oral antibiotics, and investigate any inadvertent effects such as increasing antimicrobial resistance or Clostridium difficile infections.