Comparison of Requirement for Postoperative Analgesics after Inhalation and Total Intravenous Anesthesia

Background: We evaluated the requirement for postoperative analgesics in 88 patients undergoing abdominal total hysterectomy with inhalation anesthesia or with total intravenous anesthesia. Methods: Anesthesia was induced in the inhalation anesthesia (GOS, n=52) group with propofol and fentanyl, and maintained with sevoflurane, nitrous oxide balanced with oxygen, and additional administrations of fentanyl up to 0.2 mg in total. The patients in the total intravenous anesthesia (TIVA, n=36) group were managed with target controlled infusion for propofol and intermittent administration of fentanyl. Effect site concentrations of fentanyl at the end of surgery were calculated using a pharmacokinetic-pharmacodynamic model. We divided the postoperative time course and evaluated the types, dosages, and prescription times of postoperative analgesics in each. Results: Both total dosage and effect-site concentration of fentanyl were higher in the TIVA group than in the GOS group, and total prescription time in the TIVA group was significantly less during the 24 hrs after the operation. Supplemental prescription intervals of buprenorphine were significantly less in the TIVA group. Since administration of fentanyl during operation was adequate, patients in the TIVA group were considered to be in a sufficient analgesic state at the end of operation. Conclusions: The postoperative pain can be reduced with TIVA.