Pharmacokinetics analysis of vancomycin initial dose in critically ill patients

Abstract number: P1983

Mas-Serrano P., Aparicio-Cueva M., Gascon-Ros I., Navarro-Martinez J., Asensi-Vilar E., Ordovas-Baines J.P.

Objectives: Pharmacokinetics analysis of vancomycin initial dose in critically ill patients.

Methods: Design: observational prospective study. Duration: six months (January 2008–July 2008). Inclusion criteria: all patients in a critical care unit and treated with vancomycin. Vancomycin initial dose: 1000 mg bid i.v. From the pharmacokinetic registry of pharmacy department were collected the following variables: demographics, infectious disease, clinical situation at the beginning of treatment (mechanical ventilation, vasoactive drugs and renal function) and through serum concentration (corresponding to sample just before the next dose) estimated in stationary state (Cpss).

The Cpss target was defined 4–8×MIC; in pneumonia AUC/MIC > 350; and in absence of antibiogram the target was 10–20 mg/L. Vancomycin serum concentration was determined by Axym® (Abbott®) autoanalyzer. Pharmacokinetics analysis was performed through the package PKS® (Abbott®). The results are expressed as mean (standard deviation).

Results: 34 patients were included (M:W 27:7). The mean age was 51.3 (17.0) years, with a mean weight of 82.8 (25.5) kg and a mean height of 171 (9) cm. The indication of treatment with vancomycin was 35.5% bacteraemia, 18% CNS, 15% pneumonia, intraabdominal infection 6%, 26% others. The mean Cockroft-Wault clearance creatinin was 153 (92) mL/min.

73.5% of patients (n = 25) treated with vancomycin required adjustment of the initial dosing. Patient distribution: 19 had Cpss below target concentration (mean dose: 12.2 (2.7) mg/kg; mean Cpss: 5.0 (2.7) mg/L) and 6 patients had Cpss above target concentration (mean dose: 12.8 (1.7) mg/kg; mean Cpss: 25.3 (4.5) mg/L). 26.5% of patients (n = 9) did not required dose adjustment (mean dose: 13.7 (1.2) mg/kg; mean Cpss: 9.2 (3.1) mg/L).

Conclusion: The high percentage of patients who need a change in dosing suggests a protocol amending the initial dose of vancomycin. Given the wide variability pharmacokinetics observed in these patients and the severity of infections in critical care units, is necessary an extensive monitoring and early pharmacokinetics in order to achieve plasma concentrations effective as soon as possible.

Session Details

Date: 16/05/2009
Time: 00:00-00:00
Session name: 19th European Congress of Clinical Microbiology and Infectious Diseases
Location: Helsinki, Finland, 16 - 19 May 2009
Presentation type:
Back to top