The Most Appropriate Parameter Correlates With Clinical Effectiveness of Vancomycin: Trough Drug Concentration or Area Under Curve (AUC)/Minimum Inhibitory Concentration (MIC)?

Several studies have shown AUC/MIC to be the better pharmacokinetic-pharmacodynamic parameter for clinical effectiveness of vancomycin. However, the 2009 consensus guideline for vancomycin therapeutic monitoring continued to recommend trough serum concentration monitoring in the clinical setting. In 2011, Patel et al showed that highly difference between AUC(72-96h) and Cmin(96h). Different dosing and creatinine clearance may reach the same trough drug level with different AUC. The investigators wonder whether trough drug level can serve as a substitute marker for AUC and as a parameter for vancomycin therapeutic monitoring.

In this study, the investigators will calculate AUC/MIC of vancomycin with published formula, analyze its correlation with patient's clinical outcome and compare that with trough drug level.