Prolonged infusion of vancomycin leads to toxicity

Introduction: Vancomycin dose recommendation in children with gram-positive infections is 15 mg/kg/dose intravenously every 6 hours. Rapid infusion of vancomycin (over less than 1 hour) may cause Red Man’s Syndrome (RMS) that requires extension of the infusion duration, which may lead to accumulation and potential toxicity if the dosing interval remains short at 6 hours. 

Objectives: This study reports the incidence of supratherapeutic vancomycin concentration (SVC, greater than 20 mg/dL) and sequelae in adolescent patients who received a prolonged infusion (PI, over 90 minutes or longer).

Study Design: A retrospective chart review of adolescents (age 12-18 years) who received PI vancomycin between September 2012 and August 2015 was performed.

Methods: Patients were included if they had serum concentrations obtained at steady state (after 3 doses). Urine output and serum creatinine (SCr) were evaluated for acute kidney injury (AKI): 50% increase in baseline SCr or urine output less than 1 mg/kg/hr.

Results: Seven patients were included in the study with two patients aged 14, two 16, one 13, and one 18 years. Five patients received 1 gm vancomycin, one received 1.25 gm vancomycin, and one received 1.5 gm vancomycin. Similarly, two patients had a every 6 hours dosing interval, four patients had an 8-hour interval, and one patient had a 12-hour dosing interval. Two patients (28.6%) experienced SVC: one patient had four levels ranging from 28.5 to 30.1 mg/dL while receiving an empirical dose of 1 gm mg over 90 minutes every 6 hours and the second patient had a level of 22.9 mg/dL while on 1.25 gm over 120 minutes every 8 hours. No patients experienced AKI.  

Conclusions: PI vancomycin caused SVC in two of the seven patients studied. Further investigation of PI vancomycin-induced nephrotoxicity is warranted.