eP531 - Oral Antibiotic Bowel Preparation for Elective Colorectal Resections: Implications Amidst Drug Shortages

Monday, June 3, 2024

8:21 AM – 8:26 AM ET, USA

Location: Baltimore Convention Center, Room 318-320

ePoster Presenter(s)

Rodrigo Arean Sanz, MD (he/him/his)

Postdoctoral Research Fellow
Beth Israel Deaconess Medical Center
Boston, MA, United States

All of the relevant financial relationships listed below have been mitigated.
This individual has no financial relationships with ineligible companies.

Author(s)

Ana Sofia Ore, MD MSc MPH (she/her/hers)

General Surgery Resident
Beth Israel Deaconess Medical Center/ Harvard Medical School
Beth Israel Deaconess Medical Center/Harvard Medical School
Boston, MA, United States

All of the relevant financial relationships listed below have been mitigated.
This individual has no relevant relationships with ineligible companies.
ZB

Zeynep Bilgili, MD (she/her/hers)

Postdoctoral Research Fellow
Beth Israel Deaconess Medical Center, Harvard Medical School
Beth Israel Deaconess Medical Center
Boston, MA, United States

All relevant financial disclosures have been managed and will be listed below.
This individual has no financial relationships with ineligible companies.
CV

Carolina Vigna, MD

Resident
Beth Israel Deaconess Medical Center
Boston, Massachusetts, United States

Disclosure information not submitted.
KC

Kristen Crowell, MD

Assistant Professor
Beth Israel Deaconess Medical Center
Boston, Massachusetts, United States

Disclosure information not submitted.
DW

Daniel Wong, MD MHS

Member of the faculty
Beth Israel Deaconess Medical Center; Harvard Medical School
Boston, Massachusetts, United States

Disclosure information not submitted.
TC

Thomas E. Cataldo, MD, FASCRS

Assistant professor of Surgery
Harvard Medical School
Boston, Massachusetts, United States

Disclosure information not submitted.

Senior Author(s)

Evangelos Messaris, MD, Ph.D, MBA

Chief Colon and Rectal Surgery
BIDMC, Harvard Medical School
Boston, Massachusetts, United States

Disclosure information not submitted.

Purpose/Background: The combination of mechanical bowel preparation with preoperative oral antibiotics is the standard recommendation for elective colorectal resections for surgical site infection (SSI) prevention. At our institution, a scheme of neomycin combined with metronidazole is employed. However, due to a national shortage, a period where only metronidazole was used ensued. We then transitioned to a combination of levofloxacin and metronidazole. This study aims to compare the rates of anastomotic leak (AL) and SSI across these three antibiotic schemes.Methods/Interventions: All patients who underwent an elective colorectal resection from August 2021 to July 2023 for benign and malignant indications were retrospectively identified at our institution. Patients were divided into three groups based on the preoperative antibiotic scheme used: neomycin/metronidazole (NM), metronidazole alone (M), and levofloxacin/metronidazole (LM). Comparisons were made within right-sided and left-sided resection groups. The primary outcome was AL rate, and SSI (deep and superficial) was used as a secondary outcome. To confirm our results, propensity score-matched analysis was used to control for differences in baseline characteristics (i.e., age, sex, preoperative immunosuppression, operative approach, and side of resection). Patients who underwent a single antibiotic scheme were matched to those who underwent a double antibiotic scheme (NM and LM).Results/Outcomes: Of 534 patients who underwent elective colorectal resection since August 2021, 47.9% were in the NM group, 39.8% in the M group, and 10.7% in the LM group. As for the primary outcome, for left-sided resections, the AL rates across the groups were 3.40% for the NM group, 11.0% for the M group, and 3.20% for the LM group (p=0.029). For right-sided resections, AL rates were 2.80% for the NM group, 13.0% for the M group, and 4.30% for the LM group (p=0.017). No differences were found between groups in terms of SSI rates. For right-sided procedures, the length of stay differed among the groups: the NM group had a mean of 4.1 days, the M group of 4.9 days, and the LM patients stayed for a mean of 2.9 days (p=0.027). These results were confirmed after propensity score-matched analysis.Conclusion/

Discussion: Our study shows that the NM scheme significantly reduces anastomotic leak rates compared to metronidazole alone. The LM scheme also outperforms M and closely aligns with NM results. These findings emphasize the benefits of a combined antibiotic scheme over metronidazole alone in elective colorectal resections.