130. Comparison of Acute Kidney Injury in Patients Receiving Vancomycin Plus Traditional- versus Extended-Infusion Piperacillin-Tazobactam in a VA Medical Center
Session: Poster Abstract Session: Antimicrobial Stewardship: Adverse Drug Events
Thursday, October 8, 2015
Room: Poster Hall
Background: Piperacillin-tazobactam (PT) and vancomycin are broad-spectrum antibiotics often used in combination to treat moderate-to-severe healthcare-associated infections.  Although these antibiotics have excellent efficacy, emerging data suggest an increased risk for acute kidney injury (AKI) with concomitant administration.  Two dosing strategies are used for PT to optimize its efficacy:  traditional-infusion dosing (30-minute infusion administered every 4 to 6 hours) and extended-infusion dosing (4-hour infusion administered every 8 hours).  Recent literature suggests an increased incidence of AKI with concomitant use, but does not specifically identify which dosing strategy for PT was utilized.  These differences in infusion duration and frequency may be important factors in the development of AKI in patients who receive both PT and vancomycin.  The purpose of this study is to compare the incidence of AKI between traditional-infusion and extended-infusion PT in combination with vancomycin at our institution.    

Methods: This is a retrospective, electronic chart review of hospitalized, non-critically-ill adults, who received the combination of vancomycin with either traditional-infusion PT or extended-infusion PT for at least 72 hours.  The primary endpoint of this study is the incidence of AKI between treatment groups.  Secondary endpoints include the incidence of AKI in selected subgroups, in-hospital mortality, 30-day mortality, and length of stay. 

Results: Fifty-seven and 62 patients were included in the traditional- and extended-infusion groups, respectively.  Acute kidney injury was observed in 15.7% (9/57) of patients in the traditional-infusion group and 29% (18/62) of patients in the extended-infusion group (p=0.12).  There was a significant increase in AKI with extended-infusion PT dosing for patients with Charlson Severity Index scores ≥ 5 (p=0.023) and patients with diabetes mellitus (p=0.008).  Mortality and length of stay were similar between both groups. 

Conclusion: This study did not find a difference in the incidence of AKI with different PT dosing strategies; however, in patients with multiple co-morbidities, including diabetes mellitus, an increased incidence of AKI was observed in the extended-infusion PT group.

Mark Knaub, PharmD1, Patrick Waters, PharmD, AAHIVP2 and Lisa Young, Pharm.D., BCPS AQ-ID2, (1)Pharmacy, Jesse Brown VA Medical Center, Chicago, IL, (2)Pharmacy (119), Jesse Brown Veterans Affairs Medical Center, Chicago, IL


M. Knaub, None

P. Waters, None

L. Young, None

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