Comparing Pharmacists’ Triggers for Hand Hygiene in a Community Pharmacy Pre and Post COVID 19 pandemic.

Abstract

Specific Aims: Determine the predictive performance of a single trough with Bayesian estimation and a one-compartment model in predicting future vancomycin concentrations. Methods: This multi-center analytical study used data obtained from retrospective medical records review. Records review was completed between January 1, 2021 through December 31, 2021. Patient records were obtained from Banner University Medical Center -South, Banner University Medical Center – Tucson, and Banner University Medical Center - Phoenix. Criteria for patient selection included prescribed vancomycin therapy with a minimum of two troughs obtained, stable serum creatinine and a BMI of less than 35. Patients were excluded for unstable renal function (more than 0.3 serum creatinine fluctuation), BMI greater than 35, age of 18 years or lower, or having fewer than two serum trough levels. Pharmacokinetic parameters were predicted using the first SVC and the fitted parameters were then used to predict subsequent SVC’s and compare to measured values. Results: A total of 450 patient charts were selected for analysis. The one trough modified Bayesian dosing method was able to predict accurate future throughs with about 40% precision. The predictive performance for the Bayesian method did degrade with subsequent SVC’s which we attributed to time- dependent pharmacokinetics. A change in pharmacokinetic parameters function, which was not necessarily reflected by a change in serum creatinine concentration was frequently observed, thus monitoring trough at least once a week is needed to detect change. Conclusions: Bayesian Analysis with a single trough concentration is useful to support vancomycin AUC dosing. Our data provides evidence of time-dependent pharmacokinetics which will require regular therapeutic drug monitoring regardless of the method used to interpret SVCs