Background: Sepsis related morbidity and mortality remains high and can be directly impacted by time to appropriate empiric antibiotic selection. Aminoglycosides (AG) are one class of antimicrobials used with beta-lactams to increase coverage of resistant gram-negative bacilli. Extended interval dosing of AG achieves better pharmacodynamics along with less risk of nephrotoxicity compared to traditional dosing. However, concern for nephrotoxicity still limits widespread use of empiric AG, particularly in the renal hypoperfusive state of sepsis. The purpose of this study is to describe the effect of adding AG to empiric antibiotic regimens of septic patients.

Methods: This was a single center, retrospective cohort of adult patients (≥ 18yr) admitted to Franciscan St. Francis Health between January 2011 and December 2013. Patients were included if they had a principal diagnosis of sepsis, identified by DRG 870, 871, and 872, then were categorized into two groups: receipt of empiric AG or non-AG antibiotic regimen. Patient demographics, source of infection, concomitant antibiotics and nephrotoxins, acute kidney injury (AKI), length of stay (LOS), and patient outcomes were assessed. Primary outcome was determined at the end of hospital stay as clinical success (clinical cure and improvement).

Results: 186 patients were included in the analysis, 97 patients received AG and 89 patients did not receive AG. Clinical success was achieved in 80.4% vs. 78.7% (p = .766) of patients, respectively. AKI occurred in 57.7% of patients in the AG group and 66.3% of patients in the non-AG group (p = .23). Mean LOS was 10.6 days vs. 9.5 days (p = .228), respectively. Mean duration of AG therapy was 2.5 days.

Conclusions: In this study, clinical outcomes and LOS were not significantly different between patients in the AG and non-AG groups. Additionally, receipt of AG did not result in higher incidence of AKI compared to those who did not. Therefore, short course, extended-interval AG can be used empirically in sepsis without added risk of nephrotoxicity.