Antibiotic Guidance in Open Pelvic Fractures: Beyond Gustilo Anderson

Authors:
Adam Gutierrez, Andrea Gochi, April Mendoza, Genna Beattie, Gregory Victorino

Body of Abstract:
Introduction
Open pelvic fractures (OPFs), defined as a fracture in the setting of a punctured skin or internal hollow viscus organ, can present in a wide variety of complex trauma settings. Guidance for antibiotic coverage in open pelvic fractures, though, remains poorly defined. We hypothesized that antibiotic coverage and duration would be highly variable in the setting of concomitant gastrointestinal (GI) and urogenital (GU) injuries when compared to those without, and despite these differences surgical site infections would remain higher in the setting of OPF with GI/GU involvement.

Methods
We retrospectively reviewed patients diagnosed with OPF between October 2014 and June 2024. Demographics and clinical data were obtained from the trauma registry of a Level 1 Trauma center. Further data on fracture patterns and antibiotics were ascertained from medical records. The primary outcome was antibiotic treatment duration, and the secondary outcome was the occurrence of infectious complications. Univariate and multivariate logistic regression analyses were performed.

Results
Among 160 patients (19 blunt, 141 penetrating injuries; median age: 30 ± 11.6 years; 85% male), 89 (55%) had concomitant GI/GU injuries. This group had higher injury severity scores (ISS, 19 vs. 11, p < 0.001), greater rates of hypotension (19% vs. 4.2%, p = 0.007), massive transfusion protocol activation (35% vs. 9.8%, p < 0.001), and exploratory laparotomy (85% vs. 17%, p < 0.001) compared to patients without GI/GU injuries. There was no significant difference in antibiotic administration timing (<1 hour) or duration (<24 hours vs. >24 hours) (Table 1). GI/GU injuries were associated with higher rates of organ space infections and deep surgical site infections (Table 1). Multivariate analysis identified rectal injuries (OR: 5.4, 95% CI: 1.6–18.0) and washout/irrigation and debridement (OR: 42.6, 95% CI: 3.9–460.6) as predictors of prolonged antibiotic courses (>24 hours). Hypotension (OR: 12.9, 95% CI: 2.5–67.5) and ICU admission (OR: 12.3, 95% CI: 3.6–42.8) were strongly associated with development of organ space infections, ISS was associated with development of deep surgical site infection (OR: 1.1, 95% CI 1.0 – 1.2), and colon injuries were associated with development of osteomyelitis (OR: 60.3, 95% CI: 1.03–3523). Only 23% of OPF with GI/GU received broad spectrum antibiotics and antibiotic variability was significantly higher after GI/GU OPF (p<0.001) (Table 1). Conclusion Antibiotic management in OPFs remains highly variable and OPF with GI/GU injuries are frequently not initiated on broad coverage despite evidence of contamination. Larger studies are required to determine the current antibiotic practice patterns and the risks of infectious complications especially osteomyelitis in this patient population.