(482) Antibiotic Duration in Patients With a Planned Relaparotomy for Intra-Abdominal Infection

Introduction: Appropriate antimicrobial therapy for the management of intra-abdominal infection (IAI) continues to evolve based on available literature. The STOP-IT trial provided evidence to support four days of antibiotics in IAI post-source control but excluded patients with a planned relaparotomy. This study aimed to determine the short- and long-term recurrent infection risk in this population.

Methods: This is a single-center, retrospective, observational study of adult patients admitted to a quaternary medical center between January 1, 2016, and August 1, 2022, with IAI requiring multiple planned laparotomies. Patients were identified using Current Procedural Terminology codes for exploratory laparotomy while receiving antibiotics. Patients were designated as receiving ≤ 5 days of antibiotics (short course) or > 5 days (long course) after source control. The primary outcome was IAI recurrence within 30 days. Secondary outcomes included re-admission for procedural intervention within 90 days, surgical site infection, hospital and ICU mortality, hospital and ICU length of stay (LOS), and total antibiotic duration for IAI.

Results: Of the 104 patients that met inclusion criteria, 78 were included in analysis. Average age was 57 years (±13.3), 56% were male, 94% Caucasian, with a mean APACHE II score of 17 (±7.09). All other baseline characteristics and clinical severity markers were similar between the two groups. Regarding the primary outcome of intra-abdominal infection recurrence, there was no difference when comparing those who received short course versus those who received long course therapy (41.2% vs. 44.4%, p= 0.781). No significant differences were found between groups with respect to secondary outcomes: readmission for procedural intervention (25.5% vs.14.8%, p= 0.390), ICU mortality (7.8% vs.11.1%, p= 0.688), and hospital mortality (13.7% vs. 22.2%, p= 0.338). Patients who received short course therapy had significantly shorter ICU LOS (6.5 vs. 11.4 days, p= 0.038).

Conclusions: In patients admitted with IAI managed with planned relaparotomy those who received a short course of antimicrobial therapy were not found to have an increase in IAI recurrence compared to those with longer courses of therapy.