Patient safety outcomes for continuous infusion vancomycin as outpatient parenteral antimicrobial therapy

Abstract Background Administration of vancomycin as a continuous infusion has been associated with reduced nephrotoxicity. Given limited published experience with continuous infusion vancomycin in outpatient parenteral antimicrobial therapy (OPAT) programs, we reviewed outcomes from our center. Methods This was a retrospective, single‐center study of adult patients receiving vancomycin OPAT as continuous or intermittent infusion for an intended treatment duration of at least 7 days. The primary outcome was time to nephrotoxicity with continuous versus intermittent infusion vancomycin while on OPAT; additional outcomes included time to any vancomycin‐associated adverse event, time to 60‐day death or readmission, and time to 60‐day emergency department encounter. Proportional hazards modeling was used to identify variables independently associated with outcomes, as well as assess the strength of association of continuous infusion with each outcome. Results Four‐hundred ninety‐two patients were included: 118 treated with continuous and 374 with intermittent vancomycin infusion. Continuous infusion was not associated with lower rates of nephrotoxicity compared to intermittent infusion (adjusted hazard ratio (aHR) 0.72, 95% CI: 0.35–1.50). There were no advantages of continuous over intermittent infusion in the rates of any adverse event (aHR 0.93, 95% CI: 0.56–1.53), 60‐day death or readmission (aHR 1.04, 95% CI: 0.68–1.61), or 60‐day emergency department encounter (aHR 1.17, 95% CI: 0.68–1.99). Vancomycin area under the concentration‐time curve (AUC) at discharge was the only modifiable factor identified that was independently associated with patient safety outcomes. Conclusion There was no appreciable benefit of continuous infusion vancomycin on outpatient safety outcomes. AUC‐centered dosing approaches warrant further investigation as strategies to improve vancomycin safety in OPAT programs.