Prophylactic antibiotic use and infectious complications in open pelvic fractures with concomitant visceral injury.

BACKGROUND

The objective of this study was to evaluate antibiotic treatment patterns administered with prophylactic intent and infectious outcomes in open pelvic fractures (OPFs). We hypothesized that antibiotic regimen and duration would demonstrate significant variability, particularly in the presence of visceral injuries, and that prolonged or broader antibiotic use would reflect clinical complexity rather than a standardized prophylactic approach.

METHODS

A retrospective cohort study of adult trauma patients (>16 years) presenting with an OPF to a Level I trauma center between 2014 and 2024, was performed. Antibiotic timing, spectrum, duration, and regimen variability were assessed for antibiotics administered at the time of OPF diagnosis and management, reflecting prophylactic intent. Prolonged antibiotic therapy was defined as > 72 h. Infectious outcomes included superficial, deep, and organ space surgical site infections (SSI), and osteomyelitis. Multivariable logistic regression was used to identify predictors of infectious complications and prolonged antibiotic use.

RESULTS

Among 160 patients (median age 30 years; 85% male), antibiotic management demonstrated substantial variability, with 16 unique antibiotic regimens used. Patients with concomitant visceral (gastrointestinal and/or genitourinary) injuries received significantly more antibiotic combinations (p < 0.001). Among patients with visceral injury, organ space SSI occurred in 28 patients. Overall SSI occurred in 37 patients. Prolonged antibiotic therapy (≥72 h) was administered in 43 patients (27%). In multivariable analysis, transfusion (OR 2.91, p = 0.033 and colorectal injury (OR 2.87, p = 0.050) were independently associated with organ space SSI. Antibiotic spectrum and duration were not independently associated with organ space SSI or overall SSI. In analysis of all SSIs, injury severity score was independently associated with infection risk (OR1.07, p = 0.020).

CONCLUSION

Antibiotic management in OPFs remains highly variable, particularly in the setting of concomitant visceral injury. Prolonged and broader antibiotic use appeared to reflect greater injury severity, contamination burden, and operative complexity rather than standardized prophylactic strategy. These findings highlight the need for prospective studies to guide antimicrobial stewardship in this complex trauma population.