Vancomycin Monitoring Research Articles

Serum Vancomycin Concentrations: Reappraisal of Their Clinical Value

Although monitoring serum vancomycin concentrations in clinical practice is commonplace, the data supporting this practice are meager. The rationale for monitoring these concentrations is to improve the effectiveness and/or reduce the toxicity of the drug. However, there are no data to suggest that monitoring serum vancomycin concentrations improves the effectiveness of therapy. In addition, despite many case reports of vancomycin-associated nephrotoxicity and ototoxicity, it is unclear whether this agent truly causes such conditions. Moreover, there is no evidence that adherence to specific ranges of vancomycin concentrations will preclude these events. Finally, vancomycin pharmacokinetics are sufficiently predictable that adequate serum drug concentrations can be obtained with dosing methods that take into account the patient's age, weight, and renal function. Safe and effective vancomycin dosage regimens can be constructed with these empirical dosing methods, whereas monitoring vancomycin levels increases the cost of therapy without improving the safety or efficacy of treatment.

Simplified dosing and monitoring of vancomycin for the burn care clinician

Vancomycin has excellent activity against Gram-positive bacteria and is often selected for use in the infected burn patient. Because of multiple-compartment pharmacokinetics, vancomycin serum concentrations can decrease dramatically in a short time period following the end of an intravenous infusion. This accounts for the widely divergent recommendations for serum vancomycin peak concentrations, e.g. from 15 mg/l up to 80 mg/l, when the time for blood sampling following the end of intravenous infusion is different. It is in general not necessary to monitor vancomycin peak concentrations, not only because its toxic potential is overrated but also because potential toxicity and therapeutic efficacy are correlated with trough concentrations. Post-distribution ‘peak’ concentrations are generally only useful for determining the optimal dosing interval for patients with impaired renal function. A dosing and monitoring paradigm for vancomycin therapy in burned adults has been devised for burn care clinicians. It provides suggested dose and dosing intervals based on body weight and creatinine clearance, with specific recommendations for regimen modification based upon the results of trough serum concentration determinations.

Therapeutic Drug Monitoring of Aminoglycosides and Vancomycin: Guidelines and Controversies

Therapeutic Drug Monitoring of Aminoglycosides and Vancomycin: Guidelines and Controversies

Measurement of Vancomycin in Renally Impaired Patient Samples Using a New High-Performance Liquid Chromatography Method with Vitamin B12 Internal Standard

A new reverse-phase high-performance liquid chromatographic (HPLC) procedure has been developed for the quantitation of vancomycin and its crystalline degradation product, CDP-1. The new HPLC procedure involves a liquid-liquid extraction pretreatment procedure and an HPLC internal standard, vitamin B12. The new HPLC procedure was used to measure 50 renally impaired patient samples. Samples were than analyzed by the monoclonal antibody Emit vancomycin assay, and the polyclonal antibody fluorescence polarization immunoassay (FPIA) vancomycin assay, and the results were compared. The Emit vancomycin assay correlated well with HPLC, but FPIA quantitated higher than Emit and HPLC. We conclude that the polyclonal antibody FPIA assay detects CDP-1 in the samples of renally impaired patients, accounting for an average of 10% of the FPIA/Emit bias, and should therefore be used with caution when monitoring vancomycin levels in renally impaired patients.

Survey of vancomycin monitoring guidelines in Illinois hospitals.

Disparity exists in published recommendations for monitoring of vancomycin serum concentrations. To evaluate the degree of disparity of practice in Illinois, directors of pathology of 202 Illinois hospitals were surveyed to assess their vancomycin monitoring practices. Of the 202 surveys mailed, 82 were returned for a response rate of 41 percent. Most hospitals have 200-500 beds (60 percent) and are nonteaching institutions (72 percent). Two thirds of the hospitals sent vancomycin to an outside laboratory for analysis. Timing of postinfusion (peak) concentrations ranged from 0 minutes following end of infusion to 360 minutes. Approximately one half of the institutions reported a peak therapeutic range of 30-40 mg/L at 30 minutes following end of infusion. A great majority of institutions were consistent in recommended trough range, with 48 of 55 reporting 5-10 mg/L. Although there is some consistency among at least half of the hospitals, there is a great deal of variability among the other half in peak monitoring guidelines.