Vancomycin therapy in critically ill patients on continuous renal replacement therapy; are we doing enough?

Area of Science:

• Pharmacology
• Nephrology
• Critical Care Medicine

Background:

• Limited recommendations exist for vancomycin dosing and monitoring in critically ill patients undergoing continuous renal replacement therapy (CRRT).
• Current practices in a Saudi tertiary hospital were retrospectively assessed for vancomycin therapy adequacy in CRRT patients.

Purpose of the Study:

• To evaluate the effectiveness of current vancomycin dosing and monitoring strategies in critically ill patients receiving CRRT.
• To identify challenges in achieving and maintaining therapeutic vancomycin levels in this population.

Main Methods:

• Retrospective chart review of adult patients receiving intravenous vancomycin and CRRT between April 2011 and March 2013.
• Inclusion criteria applied to 32 of 68 patients who met study requirements.

Main Results:

• Fifty-one percent of patients were male, with a median age of 62.5 years and high APACHE II and Charlson Comorbidity Scores.
• The mean vancomycin dose was 879.9 mg daily, with significant variability in serum vancomycin levels (6.6–41.3 mg/L).
• While 75% of patients achieved a vancomycin level >15 mg/L at least once, only 34.3% maintained this level on two or more occasions.

Conclusions:

• Achieving and sustaining therapeutic vancomycin levels is difficult in critically ill patients on CRRT.
• Aggressive vancomycin dosing regimens and diligent, frequent therapeutic drug monitoring are necessary for optimal outcomes.