Safety of Extended Infusion Piperacillin-Tazobactam plus Vancomycin versus Standard Infusion Piperacillin-Tazobactam plus Vancomycin in General Medicine Patients with a diagnosis of Healthcare associated Pneumonia

Objective: The primary safety objective is Acute Kidney Injury (AKI), defined as an increase in serum creatinine of at least 0.5 mg/dL or a 50% increase in serum creatinine from baseline at any time during antibiotic therapy. The objective of this study is to assess safety of Extended Infusion Piperacillin-tazobactam (EIPT) and vancomycin therapy versus Standard Infusion Piperacillin-tazobactam (SIPT) and vancomycin in general medicine patients, and to evaluate if one treatment modality predisposes patients to a greater risk of nephrotoxicity. Setting: Data from a large academic medical center was analyzed over a 3 month period pre and post implementation of extended infusion piperacillin-tazobactam protocol. Design: A retrospective analysis was conducted comparing patients admitted to the hospital with a diagnosis of Healthcare Associated Pneumonia (HCAP) who received EIPT plus vancomycin versus SIPT plus vancomycin. Patients: Adult hospitalized patients on combination therapy with two or more Serum Creatinine (SCr) measurements were included. Patients were excluded if they are less than 18 years of age, are pregnant, or if they are on any form of dialysis including continuous renal replacement therapy. Conclusion: A total of 241 patients were evaluated for AKI. Safety outcomes were compared between the two treatment groups and contributing factors for developing AKI were also assessed. The incidence of AKI was significantly higher in the SIPT and vancomycin group (20.0%) compared with the EIPT and vancomycin group (10.0%) in the analysis (p=0.033). There were no significant differences in the baseline characteristics between the groups with the exception of a higher percentage of patients with a diagnosis of hypertension in the EIPT and vancomycin group (p<0.05).