Comparison of Length of Hospital Stay and Cost of Intravenous and Oral N-acetylcysteine in Acute Acetaminophen Toxicity

Abstract

Specific Aims: To determine the cost of treatment of oral and intravenous n-acetylcysteine (IV NAC) in acute acetaminophen (APAP) toxicity using the length of treatment and length of hospital stay. Methods: A retrospective chart review of Arizona Poison and Drug Information Center electronic records from 2009-2012 and January-June 2013 were evaluated. The following information was collected: age, sex, use oral or intravenous NAC, length of treatment, length of hospital stay (intensive care unit (ICU) and non-ICU) and use of antiemetic. The mean length of stay (MLOS) was calculated for each group as well as the cost of IV and oral NAC. These means were then compared using t-test for independent groups to test for significance. The average total cost of IV and oral NAC treatment was calculated by using monetary values from primary literature. A sensitivity analysis was performed to test the possible effects of an increase or decrease of the final costs by 5 to 10%. Main Results: Patients (≥18 yrs) being treated with IV or oral NAC for acute APAP toxicity (≤8 hours prior to ingestion) were included in this study. A total of 47 patients met the inclusion criteria. Length of hospital stay was shorter in patients receiving IV NAC (42.5% 24-24hr; 37.5% 48-72hr) compared to patients receiving oral NAC (28.6% 48-72hr, 71.4% >72hrs; p<0.001). Total cost of ICU/non-ICU stay in patients receiving IV NAC ($8,720/$3010) was less than patients receiving oral NAC ($12,321/$4703); however, cost of IV NAC-extended (37hrs) in ICU/non-ICU ($13,153/$5535) was greater than oral NAC. The sensitivity analysis performed demonstrated that an increase or a decrease by 5 to 10% in change of cost does not affect our final conclusion. Conclusion: The cost of treatment of IV NAC is lower due to shorter LOS of patients treated with IV NAC (p<0.001). However, when an extended course of treatment is medically necessary for patients on IV NAC then the cost of treatment with IV NAC exceeds the cost of treatment with oral NAC.