Initial vancomycin dosing recommendations for critically ill patients undergoing continuous venovenous hemodialysis
Lyndsay M van de Vijsel1, Sandra A N Walker, Scott E Walker
1, BScPhm, is with the Department of Pharmacy, St Boniface Hospital, Winnipeg, Manitoba.
The Canadian Journal of Hospital Pharmacy
|April 6, 2012
Summary
Vancomycin dosing for critically ill patients on continuous venovenous hemodialysis (CVVHD) is challenging due to variable pharmacokinetics. Initial dosing recommendations may not reliably achieve target concentrations, necessitating therapeutic drug monitoring.
Area of Science:
- Pharmacology
- Nephrology
- Critical Care Medicine
Background:
- Antimicrobial therapy delays increase mortality in critically ill patients.
- Current vancomycin dosing guidelines lack data for patients on continuous venovenous hemodialysis (CVVHD).
Purpose of the Study:
- To establish practical vancomycin dosing recommendations for critically ill patients undergoing CVVHD.
- To analyze vancomycin pharmacokinetics in this specific patient population.
Main Methods:
- Chart review of 24 critically ill adult patients receiving vancomycin and CVVHD.
- Determination of mean pharmacokinetic parameters.
- Monte Carlo simulation for initial dosing regimen development.
- Targeting steady-state trough concentrations of 15-20 mg/L.
Main Results:
- Mean vancomycin pharmacokinetic parameters were determined, including elimination rate constant, half-life, volume of distribution, and clearance.
- Initial dosing regimens were proposed for both intermittent and continuous vancomycin infusions.
- Monte Carlo simulations indicated a low probability of achieving target vancomycin concentrations (15-20 mg/L) with proposed initial regimens.
Conclusions:
- Significant variability in vancomycin pharmacokinetics was observed in patients undergoing CVVHD.
- Empiric vancomycin dosing recommendations based on small, heterogeneous studies may be unreliable.
- Therapeutic drug monitoring is crucial for optimizing vancomycin therapy in this population.
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