Dosage adjustment of vancomycin in continuous infusion in critically ill-patients

Introduction. - As the susceptibility of staphylococcal strains to glycopeptides rises, it is becoming necessary to increase vancomycin dosages. Objective. - To evaluate an administration protocol for vancomycin using continuous infusion with a loading dose of 30 mg/kg followed by 30 mg/kg per 24 h in intensive care patients presenting creatinine clearance (CLc) greater than 50. Results. - A total of 22 patients were included in the study. Serum vancomycin concentrations after 24 h (C24h) ranged from 25 to 30 mg/l in seven of 14 patients with CLc less than 120 ml/min (50 %), compared with three patients (21 %) with C24h greater than 35 mg/l and four patients (29 %) with C24h less than 25 mg/l. However, C24h was less than 20 mg/l for the eight patients with CLc greater or equal to 120 ml/min. Bacteriological data was available for eight of the 14 patients with CLc less than 120 ml/min, and in these eight patients, the C24h/MIC was greater or equal to 8; seven of these patients had an AUC/MIC greater or equal to 350. Conclusion. - Assay of serum vancomycin concentrations after 24 h of treatment is necessary to enable rapid adjustment of vancomycin concentration in order to improve therapeutic efficacy or avoid nephrotoxicity. (C) 2009 Elsevier Masson SAS. All rights reserved.