Incidence and Risk Factors of Acute Kidney Injury in Patients Receiving Concomitant Vancomycin and Continuous-Infusion Piperacillin/Tazobactam: A Retrospective Cohort Study

Annals of Pharmacotherapy, Ahead of Print.
Background: During a recent shortage of small-volume parenteral solutions, some hospitals administered piperacillin/tazobactam via continuous infusion to utilize larger fluid volumes. Although the incidence of acute kidney injury (AKI) is well documented for patients receiving intermittent or extended-infusion piperacillin/tazobactam with concomitant vancomycin, no literature exists documenting the incidence of AKI in patients receiving continuous-infusion piperacillin/tazobactam. Objective: The objective of this study is to examine the incidence and predictors of AKI in patients who received continuous-infusion piperacillin/tazobactam with concomitant intermittent-infusion vancomycin (VPT-CI) at a community hospital. Methods: A retrospective cohort study was performed on patients who received VPT-CI between December 2017 and March 2018. Patients were eligible for inclusion if they were at least 19 years of age and received at least 48 hours of combination therapy. The primary outcome was incidence of AKI. The secondary outcome was an assessment of patient and treatment characteristics to determine predictors of AKI. Results: A total of 120 patients were included in the study. The incidence of AKI in patients who received VPT-CI was 31.7%. Based on binary logistic regression analysis, risk factors associated with increased risk of AKI included admission to the intensive care unit and baseline creatinine clearance less than 60 mL/min. Conclusion and Relevance: The incidence of AKI for VPT-CI found in this study was comparable to that found with intermittent and extended-infusion piperacillin/tazobactam with concomitant vancomycin in prior literature. Additional research should further analyze risk factors for the development of AKI for patients on concomitant vancomycin and piperacillin/tazobactam therapy.