Correlates and Economic and Clinical Outcomes of an Adult IV to PO Antimicrobial Conversion Program at an Academic Medical Center in Midwest United States

Abstract

The study objectives were to evaluate the correlates and outcomes of a parenteral (IV) to oral (PO) antimicrobial conversion program at a Midwest US Academic Medical Center with the hypothesis that it will be associated with reduced drug costs. Patient-level data (n = 237; sex, race, admission source, admission status, admission severity, risk of mortality [relative expected, admission], and early death) were extracted from the Clinical Data Base/Resource Manager. Medication-level, drug-encounter data (n = 317; antibiotic/dose/route/frequency/duration, conversion status, 10-day IV/PO switch-eligibility criteria) were extracted from patient’s hospital medical records. Univariate analyses using chi-square or Fisher’s exact test for categorical variables and Wilcoxon rank-sum test for continuous variables showed patients not converted (n = 149) versus converted (n = 88) at some point from IV to PO were more likely to be of white race and had higher risk of relative expected mortality. By applying the unit drug cost (derived from 2010 Thomson Reuters RED BOOK^TM) and labor costs for IV/PO administration, both per dose, the overall 1-month drug cost-saving estimates in 2010 in US dollars were US$5242 from converting and US$8805 savings missed from not converting 518 and 1387 switch-eligible antibiotic doses, respectively. Despite sample-size limitations, this study demonstrated correlates and missed opportunities to convert antimicrobials from IV to PO, which warrants providers’ attention.