Prospective evaluation of vancomycin therapeutic usage and trough levels monitoring

Vancomycin is the cornerstone of parenteral therapy for serious methicillin resistant Staphylococcus aureus infections. Optimal dosing of vancomycin is patient specific due to its narrow therapeutic window. The objective of this study is to evaluate the appropriate use of vancomycin focusing on the indication, dose, and therapeutic level monitoring.

A prospective observational study was conducted in a tertiary care hospital over a 3- month period. A data collection form was used to gather information on 93 patients receiving vancomycin. Study outcomes were assessment of the appropriateness of vancomycin indication, dose, and therapeutic trough level.

The use of vancomycin both empirically and after culture results was appropriate in 78.5 % of the patients. More than half of the patients (51.6 %) were given an inappropriate dose of vancomycin per actual body weight, creatinine clearance, and  indication. Regarding therapeutic vancomycin monitoring, 69.0 % had inappropriate trough level monitoring. Only 15.7 % of the 166 measured troughs were within the target therapeutic level for the corresponding indication.

This study demonstrates the high level of inappropriate use of vancomycin. This is mainly attributed to inappropriate dose and trough level monitoring. Interventions to improve vancomycin prescribing and monitoring practices are needed. The presence of an interdisciplinary team may improve the appropriate use of medications with a narrow therapeutic index such as vancomycin.