Therapeutic drug monitoring
-
Review
AUC versus peak-trough dosing of vancomycin: applying new pharmacokinetic paradigms to an old drug.
To compare and contrast the pharmacokinetic/pharmacodynamic foundations of traditional "peak-trough" vancomycin dosing methods versus newer "area under the curve" (AUC) strategies. To propose a new AUC-based dosing chart for empirically determining an initial vancomycin dosing regimen designed to achieve a desired AUC24 using the minimum inhibitory concentration (MIC), creatinine clearance (CrCl), and vancomycin clearance (ClVanco). ⋯ An understanding of pharmacokinetic and pharmacodynamic principles, including the relevance of AUC in relation to MIC, enables clinicians to make the best use of vancomycin dosing options. The proposed dosing chart is pharmacokinetically valid but has yet to be applied clinically. It provides a foundation for further study of how clinicians can determine an optimal AUC-based starting vancomycin dosing regimen without having to derive ClVanco or AUC24.
-
For pain management, opioid therapy is a mainstay for treating acute pain and relieving moderate to severe chronic pain. Quantitative measurement of opioids and their metabolites in urine is used mainly for confirmation of screened results obtained for clinical and forensic purposes. Due to limitations in interpretation of urine results for pain management testing purposes, the use of blood or serum to assess opioids and their metabolites may be of benefit. ⋯ The method uses solid-phase extraction of 500 µL of sample with quantitation by liquid chromatography-tandem mass spectrometry. The assay is linear from 1.0 to 100 ng/mL and has a between-day coefficient of variation of <10%. The major advantage of this method is that a single extraction can detect hydrocodone and its metabolites and other opiates or opioids that patients frequently use simultaneously with hydrocodone.
-
Retrospective studies have identified elevated vancomycin trough levels >20 mg/L as a predictor of nephrotoxicity with a high variable incidence of 12.6%-65%. However, the elevated levels may represent the effect of renal compromise rather than the cause of nephrotoxicity. The aim of this study was to report the incidence of acute kidney injury (AKI) and associated risk factors in adult patients with vancomycin trough levels >20 mg/L in a prospective Pharmacovigilance Program from Laboratory Signals at a Hospital. ⋯ The Pharmacovigilance Program from Laboratory Signals at a Hospital provides early identification and early evaluation of cases. Renal function and vancomycin trough levels should be closely monitored from the second week of treatment in adults, intensive care patients, and those who receive concurrent nephrotoxic agents.
-
Given the low therapeutic index, the large interindividual variability in systemic exposure and the positive exposure-efficacy relationship of sunitinib, there is a rationale for therapeutic drug monitoring (TDM) of sunitinib. To support TDM, a method for determination of sunitinib and its active metabolite (N-desethyl sunitinib) has been developed and validated. ⋯ This method has been applied successfully for routine TDM purposes for patients treated with sunitinib. Moreover, reliable results with a rapid turnaround time were obtained when performing a short analytical run containing only 3 calibrators and 1 QC sample.
-
Meropenem is an effective β-lactam antibiotic that is frequently used to treat serious infections in both intensive care unit (ICU) and febrile neutropenic hematology/oncology (Hem/Onc) patients. Studies suggest that to be effective, meropenem concentrations must be maintained above the inhibitory concentrations for the majority of a dosing interval. However, the pharmacokinetics (PK) of meropenem seem to differ in critically ill patients compared with healthy or less ill subjects used to select labeled dosing regimens. ⋯ Standard meropenem dosing regimens were inadequate in many critically ill febrile, neutropenic Hem/Onc, and septic ICU patients. These data suggest a role for meropenem concentration monitoring in such patients.