Opioid sparing effects of intravenous and oral acetaminophen in hip fracture patients: A population-based study

Study objective: Acetaminophen (APAP) and intravenous acetaminophen (IVAPAP) has been proposed as a part of many opioid-sparing multimodal analgesic pathways. The aim of this analysis was to compare the effectiveness of IVAPAP with oral APAP on opioid utilization and opioid-related adverse effects. Design: Retrospective study of population-based database. Patients: The Premier Healthcare database was queried patients undergoing surgery for a primary diagnosis of hip fracture from 2011 to 2019 yielding 245,976 patients. Primary exposure was use of IVAPAP or oral APAP on the day of surgery. Interventions: None. Measurements: The primary outcome of interest was opioid utilization over the hospital stay, secondary outcomes included opioid-related adverse effects, length, and costs of hospital stay. Mixed effect models measured the association of IVPAP and APAP and outcomes. Main results: In the study population 30.67% (75,445) received at least 1 dose of IVAPAP on the day of surgery. Upon adjusting for relevant covariates, patients who received IVPAP on the day of surgery had slightly higher opioid use standardized by length of hospital stay (2.8% CI: 2%, 3.6%; p < .001), higher hospital cost (2.7% CI: 2.1%, 3.4%), and higher odds of naloxone use (1.18, CI: 1.1, 1.27; p < .001) when compared with patients who received oral APAP. Conclusions: In this population, IVAPAP use on the day of surgery failed to reduce opioid use or associated opioid related adverse effects when compared with oral APAP. IVAPAP was associated with increased overall costs, opioid requirements, and naloxone use. These results do not support the use of IV over oral APAP routinely for hip fracture surgery patients.