Intravenous scheduled administration of acetaminophen in analgesia after pancreatectomy

Abstract

Introduction: The concept of multimodal analgesia has become widespread. Intravenous scheduled administration of acetaminophen has also used commonly for the management of postoperative pain. The aim of this study is to investigate the usefulness and the safety of intravenous scheduled administration of acetaminophen after pancreatectomy. Method: The study included 59 patients who underwent highly invasive pancreatectomy including pancreatoduodenectomy and total pancreatectomy at our institute between January 2017 and November 2018. The patients who underwent laparoscopic pancreatectomy were excluded. All patients were received epidural anesthesia as a baseline analgesic modality. Twenty four patients who were received scheduled acetaminophen were classified in the acetaminophen group, and 35 patients who were not received scheduled acetaminophen were classified in the control group. 1000 mg of acetaminophen was administrated intravenously every 6 hours until postoperative day 2. For the patients weighting less than 50kg, the dose of acetaminophen was 15 mg/kg. We investigated clinical features including the frequency of the use of patient-controlled epidural analgesia (PCEA) and non-steroidal anti-inflammatory drugs, adverse events associated with analgesia, body temperature, and liver function between two groups. Result: There were no significant differences in age, sex, operation time, opeative blood loss, first oral intake (postoperative day), and hospital stay. The flow rate of epidural analgesia and the maximum score of numerical rating scale (NRS) of the control group were significantly higher than the acetaminophen group. Regarding liver function including serum level of AST, ALT, and total bilirubin, AST on postoperative day 3 was significantly higher in the acetaminophen group; however, there were significant differences in other liver function tests within one week. Adverse events associate with analgesia including vertigo and vomiting were not significantly different between two groups. Conclusion: Intravenous scheduled administration of acetaminophen was found to be useful and safe in analgesia after highly invasive pancreatectomy.