Brian L Erstad

PMID: 17257479;Abstract:

Objective: This decision-analytic study was intended to determine the expected cost-effectiveness of linezolid compared to vancomycin for treating surgical site infections (SSIs) caused by methicillin-resistant Staphyloccocus aureus (MRSA) from the perspective of a tertiary-care academic medical center. Research Design and Methods: This study is a cost-effectiveness analysis based on a modeling approach for the treatment of MRSA SSIs. Three clinical scenarios were considered in the decision analysis: (1) treatment with intravenous (IV) vancomycin during hospitalization and after discharge with home-care follow-up; (2) treatment with IV vancomycin during hospitalization, followed by oral linezolid after discharge; (3) treatment with oral linezolid during hospitalization and after discharge. Cost data was obtained from internal and external sources. Cure rate probabilities for MRSA SSIs were obtained from records at the medical center and from results of a randomized, multicenter trial. Healthcare costs for each scenario were obtained from the medical center, healthcare buying groups, and national databases. The robustness of the baseline cost-effectiveness determination was evaluated using sensitivity analyses over a broad range of costs and probabilities. Results: Treatment with oral linezolid during hospitalization and after discharge (scenario 3) was associated with lower costs ($8923, $11 479, and $12 481, respectively) and greater effectiveness (0.867, 0.787, and 0.707, respectively) compared to the IV vancomycin/oral linezolid switch (scenario 2) and IV vancomycin (scenario 1), so it dominated the latter options in the base-case, incremental cost-effectiveness analysis ($10 292, $14 486, and $17653 per MRSA SSI cure, respectively). Furthermore, the sensitivity analysis demonstrated that the IV vancomycin/oral linezolid (scenario 2) option would be the expected cost-effective choice only if the length of hospitalization for this scenario was less than 6 days or if the probability of cure with oral linezolid (scenario 3) was less than or equal to 0.72; otherwise, the oral linezolid option was dominant. A major limitation of this study is the utilization of probability estimates from both institutional and published research sources. Additionally, the success rates for linezolid were obtained from one relatively small randomized, open-label trial. Conclusions: Using decision-analytic modeling, treatment with oral linezolid during hospitalization and after discharge is expected to be the most cost-effective approach for treating SSIs caused by MRSA. © 2007 Librapharm Limited. All rights reserved: reproduction in whole or part not permitted.

PMID: 11086778;Abstract:

Background: Once-daily dosing regimens of aminoglycosides are routinely used in critically ill trauma patients. However, the pharmacokinetic parameters are variable in these patients. The purpose of this study was to evaluate the pharmacokinetics of aminoglycosides in critically ill trauma patients receiving once-daily dosing regimens. Methods: At least two aminoglycoside concentrations were measured in each patient. Population pharmacokinetic parameters were estimated on the basis of a one-compartment structural model and the program nonlinear mixed effects modeling. Results: Fifty-three aminoglycoside concentrations from 19 patients were analyzed. The aminoglycoside clearance was 5.47 L/h. The mean volume of distribution was 22.2 L (0.3 L/kg). The mean half-life was 2.9 hours. Serum-aminoglycoside concentrations were undetectable for longer than 12 hours in 4 of 19 patients. Weight, age, or serum creatinine did not significantly explain the variability. Conclusion: There is marked variability in aminoglycoside pharmacokinetic parameters in critically ill trauma patients. This may lead to prolonged drug-free intervals. Individualized dosing of critically ill trauma patients on the basis of at least two serum-aminoglycoside concentrations seems indicated when using once-daily dosing regimens.

PMID: 19017823;Abstract:

The intensive care unit (ICU) continues to be a major focus of decentralized pharmacy activities in health systems that care for critically ill patients. This is not surprising, given the need for rapid decision-making involving unstable patients, the large number of powerful medications typically used per patient, the high cost of many drugs used in the ICU and, most importantly, the evidence demonstrating the benefits of having a pharmacist as part of an interdisciplinary team. The purpose of this paper is to highlight important issues to consider when introducing or developing critical care pharmacy services beginning with the establishment of basic services and continuing through practitioner development, guideline/ protocol development and implementation, patient safety, residency training, and research.

PMID: 14625670;Abstract:

Objective: To derive recommendations for the dosing of commonly used medications in the morbidly obese patient in the ICU. Data sources: Articles were obtained through computerized searches involving MEDLINE. The bibliographies of retrieved publications and textbooks were reviewed for additional references. Study selection: All studies involving the pharmacokinetics or pharmacodynamics of medications in obese subjects or patients. Data extraction: The emphasis was on studies involving morbidly obese patients but, in the absence of such data, investigations involving lesser forms of obesity were extracted. Data synthesis: There is a paucity of data upon which to make recommendations for dosing commonly used medications in the morbidly obese patient in the ICU, although recommendations were provided based on the available information. Conclusions: There is clearly a need for more investigations involving dosing regimens of medications in the morbidly obese population. Until such studies are available, the clinician must try to derive the best dosing regimens for medications based on the limited pharmacokinetic data available for some agents and clinical judgement.

The primary objective of this study is to determine the activities of pharmacists that lead to medication error interception in the emergency department (ED).