From overlooked to just right - putting the focus on metronidazole infusion timing for colorectal surgical prophylaxis

Sep 29, 2026

Uploaded by Jasmine

Preoperative prophylaxis efficacy depends on antibiotic infusion completion before incision. In a colorectal program, metronidazole infusions were often not finished on time, unlike cefazolin. A multidisciplinary initiative standardized metronidazole administration timing to improve infusion completion rates. The study evaluated how this process change affected surgical site infection outcomes in colorectal surgery, addressing adherence to guideline-recommended infusion windows and operative logistics.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages3

Reading Time8 min

AccessFree to download

Introduction

Antibiotic infusion timing and guideline windows

Metronidazole specifics and institutional variability

Methods and intervention

Standardizing metronidazole administration

Results and impact

Antimicrobial Stewardship & Healthcare Epidemiology (2026), 6, e13, 1–3 doi:10.1017/ash.2025.10260 Concise Communication From overlooked to just right: putting the focus on metronidazole infusion timing for colorectal surgical prophylaxis Peter Oakes MD1 , Lindsay E. Donohue PharmD2, Sunny Chiao MD3 , Susan Ketcham MSN4, Traci Hedrick MD5, Rachele Olivier MSN6 and Amy J. Mathers MD1 1Division of Infectious Diseases & International Health, Department of Medicine, University of Virginia Health, Charlottesville, VA, USA, 2Department of Pharmacy, University of Virginia Health System, Charlottesville, VA, USA, 3Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA, USA, 4Perioperative Services, University of Virginia Health System, Charlottesville, VA, USA, 5Colon and Rectal Surgery, Division of General Surgery, University of Virginia Health System, Charlottesville, VA, USA and 6Department of Quality and Performance Improvement, University of Virginia Health System, Charlottesville, VA, USA Abstract Preoperative prophylaxis efficacy depends on antibiotic infusion completion before incision. In our colorectal program, metronidazole often wasn’t completed on time, in contrast to cefazolin. A multidisciplinary effort standardized its administration timing, improving infusion completion rates. We evaluated the impact of this intervention on surgical site infections in colorectal surgery. (Received 7 September 2025; accepted 3 December 2025) Introduction Both the timing and selection of antimicrobial prophylaxis (AP) reduce the risk of surgical site infections (SSI), but the logistics around varied infusion times are often overlooked.1 National AP guidelines jointly issued in 2013 by the American Society of Health-System Pharmacists (ASHP), the Infectious Diseases Society of America, the Surgical Infection Society, and the Society for Healthcare Epidemiology of America recommend that AP should be infused (both initiated and completed) within a 60 min window before incision.2 However, this recommendation is based primarily on studies focused on first-and second-generation cephalosporins infused via rapid intravenous (IV) push over a number of minutes by an anesthesiologist prior to skin incision. Vancomycin and fluoroquinolones are well known exceptions and are permitted a longer 120 min infusion window, due to rate limitations precluding the ability to completely administer doses in the shorter time frame. Subsequent studies have validated the consequences of failing to adhere to this earlier window for vancomycin, noting increased SSI rates when infusions are initiated too close to the time of incision and describing the significant resource allocation required to coordinate the complex logistics of an operating room setting.3,4 Despite the need for slow IV drip administration and a long half-life with active metabolites promoting adequate tissue concentrations for prolonged periods of time, metronidazole (MTZ) has not been clearly specified in this Corresponding author: Peter Oakes; Email: [poakes16@gmail.com](poakes16@gmail.com) Cite this article: Oakes P, Donohue LE, Chiao S, et al. From overlooked to just right: putting the focus on metronidazole infusion timing for colorectal surgical prophylaxis. Antimicrob Steward Healthc Epidemiol 2026. doi: 10.1017/ash.2025.10260 guideline carve-out, and one prior study has noted challenges with completing MTZ infusions prior to skin incision when given as a 30 min infusion by anesthesia in the operating room.5 MTZ IV infusion is only commercially supplied as a diluted and neutralized 500 mg/100 mL solution, as the undiluted reconstituted product is not appropriate for direct IV injection due to its low pH. In the United States, it is indicated for use as preoperative AP in patients undergoing elective colorectal surgery (COLO) at a dose of 15 mg/kg (approximately 1 g for a 70 kg patient) infused over 30 – 60 min and completed approx

FAQs

Why is infusion completion before incision important for surgical prophylaxis?

Preoperative prophylaxis effectiveness depends on antibiotic infusion being completed before incision to ensure adequate perioperative exposure.

What problem prompted the intervention in the colorectal program?

Metronidazole infusions were frequently not completed on time before incision, unlike cefazolin.

How was metronidazole administration standardized?

A multidisciplinary effort standardized the administration timing of metronidazole to improve infusion completion rates prior to incision.

Sep 29, 2026

Uploaded by Jasmine