Monitoring strategies and vancomycin-associated acute kidney injury in patients treated at home.

Abstract

Objectives: The 2020 vancomycin consensus guidelines recommend AUC-guided dosing over trough-based dosing to decrease nephrotoxicity. This study was performed to add data comparing these dosing methods in the outpatient setting.

Methods: This retrospective cohort study compared trough-guided versus AUC-guided dosing in patients receiving vancomycin through two home infusion pharmacies (HIPs). Multivariate analysis was performed to report adjusted relative risks, adjusting for patient demographics and clinical characteristics. Eligible patients were ≥18 years old, had an absolute neutrophil count of ≥1000 cells/mm3, a baseline serum creatinine of <2.0 mg/dL at HIP intake, and ≥7 days of IV vancomycin at home. Primary outcome was rate of acute kidney injury (AKI) events, defined as the number of AKI events per treatment days. Secondary outcomes were rate of 30 day hospital readmission and number of HIP interventions (vancomycin dose changes).

Results: Six hundred and sixty patients were included (303 trough, 357 AUC). The mean number of AKI events was 0.84 per treatment day for trough-guided versus 0.63 for AUC-guided dosing (P = 0.11). In adjusted models, there were no significant associations between the exposure and AKI events [relative risk (RR) = 0.8, 95% CI 0.5-1.2, P = 0.26], 30 day hospital readmissions (RR 1.0, 95% CI 0.8-1.3, P = 0.71) or number of pharmacy interventions (RR = 1.0, 95% CI 0.9-1.2, P = 0.67).

Conclusions: There was no significant difference in AKI rates among patients receiving vancomycin via trough- or AUC-guided monitoring and dosing through a HIP. Further evaluation is needed to determine how to improve AKI rates using AUC-guided monitoring and dosing among patients receiving vancomycin therapy at home.