Optimal Target Concentration of Alfentanil for the Sedation of Urologic Surgical Patients / 대한마취과학회지

ABSTRACT

BACKGROUND: The purpose of this study was to define the optimal target concentration of alfentanil effective in achieving a sedative, antianxiety and analgesic effect during spinal anesthesia in urologic patients. METHODS: Sixty patients underwent spinal anesthesia with 0.5% hyperbaric bupivacaine 12-18 mg and received a target controlled infusion (TCI) of alfentanil with 0 ng/ml (group A0, n = 15), 20 ng/ml (group A20, n = 15), 30 ng/ml (group A30, n = 15) or 40 ng/ml (group A40, n = 15). Sedation scale, bispectral index (BIS), anxiety level and infusion rate of alfentanil were checked during the operation. RESULTS: Sedation scale was significantly higher in group A30 (3.3) and A40 (3.8) than group A0 (1.9) and A20 (2.5)(P<0.05). Incidences of intraoperative hypotension, respiratory depression, postoperative nausea and vomiting, and dizziness were significantly higher in group A40 than the other groups (P<0.05). There were no significant differences in BIS, anxiety level and incidences of recall of the operative procedure among the groups (P<0.05). CONCLUSIONS: TCI of alfentanil with 30 ng/ml produces effective sedation and antianxiety effect without significant side effects during spinal anesthesia.