The use of intravenous (IV) acetaminophen (APAP) for fever has not been thoroughly studied in neurocritical care (NCC) patients, in whom a temperature of ≥38°C is associated with poor outcomes and treatment to normothermia is common practice. This retrospective study evaluated NCC patients admitted between May 1, 2012, and April 30, 2013, and received at least one dose of IV or oral (PO) APAP for a body temperature of ≥38°C. The primary aim of this study was to compare the reduction in body temperature (RIT) between IV and PO APAP, calculated as the change in temperature before and 0.5, 1, 2, 3, and 6 hours after administration. Descriptive statistics were used to assess use characteristics, and Kruskal-Wallis and Mann-Whitney U tests were used for between-group differences. There were 142 NCC patients who received a total of 405 IV APAP and 253 PO APAP doses. Seventy percent of all APAP doses resulted in a temperature of <38°C within 6 hours. The median oral body temperature before APAP was 38.8°C and 38.6°C for IV and PO APAP, respectively (p < 0.01). The median RIT at 0.5 (IV 0.25°C vs. PO 0.2°C), 1 (IV 0.4°C vs. PO 0.2°C), 2 (IV 0.7°C vs. PO 0.5°C), 3 (IV 0.9°C vs. PO 0.6°C), and 6 (IV 1°C vs. PO 0.8°C) hours was significantly greater for IV APAP than for PO APAP at all time points (p < 0.05). Patients with an acute ischemic stroke and patients with an intracerebral hemorrhage had a statistically significantly greater RIT with IV APAP therapy. IV APAP administered to febrile NCC patients was associated with a significantly greater RIT than PO, but 70% of all APAP doses resulted in a body temperature of <38°C within 6 hours. Further prospective studies are needed to determine if IV APAP improves clinical outcomes.
Keywords: acetaminophen; fever; intensive care; neurocritical care; neurological injury; temperature.