ABSTRACT
BACKGROUND: The purpose of the study was to evaluate the effect of postural change on hemodynamics using thoracic eletrical bioimpedance (TEB) device during general anesthesia with enflurane-N2O-O2 and lumbar epidural anesthesia. The TEB device is safe, reliable and non-invasive way to measure hemodynmic values continuously. METHODS: General anesthesia (twenty patients) was induced by administration of pentotal sodium 5 mg/kg and succinylcholine 1 mg/kg intravenously, and was maintained with 1 vol% of enflurane, N2O-O2 (2 l/min-2 l/min) and vecuronium 0.1 mg/kg. Epidural anesthesia (twenty patients) was performed at the level of L3-4 epidural space using 20 ml of 2% xylocaine mixed with epinephrine (5 microgram/ml). Hemodynamic changes were measured before induction, 1 and 5 minutes after intubation or epidural injection, 1, 5, 10, 20, 30 minutes after head- down tilt and 1, 5, 10 minutes after returning to the supine position. RESULTS: HR and LVSWI were minimaly affected in group E with epidural anesthesia compared to group G with general anesthesia. BP (SBP, DBP, MAP) and SVRI were remarkably increased in group G compared to group E. BP and SVRI showed rapid increse 1 minutes after head-down tilt in group G (p<0.01) and decreased gradually thereafter. SI and CI were decreased significantly in group G compared to group E (p<0.001). SI was unchanged but CI was decreasd significantly after head-down tilt in group E (p<0.05). EDI and ACI showed lower values decreased in general significantly in group G compared to group E (p<0.05). CONCLUSIONS: All hemodynamic changes were more predictable, gradual, less variable, and stable in the group with epidural anesthesia compared to the group with general anesthesia for hysterectomy.