A retrospective analysis of intravenous acetaminophen use in spinal surgery patients

OBJECTIVE: This study aimed to determine if intravenous acetaminophen [paracetamol] (IV APAP) could decrease visual analog pain scores (VAS), opioid exposure and subsequent opioid related adverse effects (nausea, vomiting, constipation) in spinal surgery patients. METHODS: Thirty four spinal surgery patients to date have received IV APAP since its addition to the formulary at our institution. The electronic medical record was accessed on all patients who received at least one dose pre or post operatively to collect postoperative opioid consumption (in morphine equivalents), number of antiemetic and laxative doses, use of naloxone, and VAS pain scores from arrival to surgical unit through postop day two. An equivalent number of patients who did not receive any IV APAP were selected and matched on the basis of opioid use prior to admission, surgery type, surgeon, age, and sex to constitute the control group. RESULTS: The IV APAP group used significantly less opioids than the control group (p=0.015). Frequency of antiemetic and laxative use and VAS pain scores did not differ significantly between the two groups. CONCLUSIONS: It appears IV APAP can be used effectively as an adjuvant pain management therapy in spinal surgery patients to decrease opioid exposure, but does not necessarily reduce the incidence of opioid related adverse effects or VAS pain scores.