We’re hoping to take a look at IV acetaminophen use. Specifically, whether post-surgical use of IV acetaminophen reduces length of stay. E.g., compare patients who got opioids with IV acetaminophen compared to opioids without IV acetaminophen. There is a paper on an inpatient database that claims yes:
Ryan N. Hansen, An Pham, Scott A. Strassels, Stela Balaban, and George J. Wan. Comparative Analysis of Length of Stay and Inpatient Costs for Orthopedic Surgery Patients Treated with IV Acetaminophen and IV Opioids vs. IV Opioids Alone for Post-Operative Pain. Adv Ther. 2016; 33(9): 1635–1645.
Saving .7 days (unadjusted analysis) or .5 days (using an instrumental variable) quantified by average length of stay. We wonder if we can do a better analysis. Maybe use a cox proportional hazards model for discharge, largely because we have that software coded. Use propensity score stratification to match the groups based on information before surgery plus what surgery they had.
We welcome input and we plan to create a protocol.