Abstract

Background: The pharmacokinetics (PK) of vancomycin in critically ill intensive care unit (ICU) patients is difficult to predict due to the scarcity of data and the variable physiology of the patient cohort.

Aims and Objectives: Since there are limited studies worldwide, this study is, therefore, intended to explore vancomycin population PK parameters in critically ill ICU patients in Hospital Raja Perempuan Zainab II, Kelantan, Malaysia.

Materials and Methods: Vancomycin population PK in ICU patients was modeled with Pmetrics. A total of 92 samples from 45 ICU patients were included in the model building and validation. The median observations per patient were three with a range of one to four observations. The median parameters estimates obtained from the final model were used to predict individual vancomycin clearance (CL) in the validation dataset.

Results: The PK of vancomycin was adequately described with a two-compartment model. Parameters included CL of 1.64 L/h, volume of distribution in central compartment of 20.0 L, rate of constant from central out to the peripheral compartment of 2.92/h, and the rate constant back from the peripheral to central compartment of 7.17/h. The developed model adequately estimated CL in the validation dataset.

Conclusion: A model to describe the PK of vancomycin was developed which adequately describes vancomycin population PK in critically ill ICU patients in Kelantan. The model might be used in initiating a vancomycin dosage regimen in the type of patients similar to the present study.

Key words: Pharmacokinetics; Vancomycin; Intensive Care Unit; Critically ill; Nonparametric