Comparison of 1.5% lidocaine and 0.5% ropivacaine epidural anesthesia combined with propofol general anesthesia guided by bispectral index

Objective： To compare the effects of epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine on propofol requirements, the time to loss of consciousness （LOC）, effect-site propofol concentrations, and the hemodynamic variables during induction of general anesthesia guided by bispectral index （BIS） were studied. Methods： Forty-five patients were divided into three groups to receive epidurally administered saline （Group S）, 1.5% （w/w） lidocaine （Group L）, or 0,5% （w/w） ropivacaine （Group R） Propofol infusion was started to produce blood concentration of 4 lag/ml. Once the BIS value reached 40-50, endotracheal intubation was facilitated by 0.1 mg/kg vecuronium. Measurements included the time to LOC, effect-site propofol concentrations, total propofol dose, mean arterial blood pressure （MABP）, and heart rate （HR） at different study time points. Results： During induction of anesthesia, both Groups L and R were similar for the time to LOC, effect-site propofol concentrations, total propofol dose, MABP, HR, and BIS. The total doses of propofol administered until 1 min post-intubation were significantly less in patients of Groups R and L compared with Group S. MABP and HR were significantly lower following propofol induction compared with baseline values in the three groups, or MABP was significantly increased following intubation as compared with that prior to intubation in Group S but not in Groups R and L while HR was significantly increased following intubation in the three groups. Conclusion： Epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine has similar effects on the time to LOC, effect-site propofol concentrations, total propofol dose, and the hemodynamic variables during induction of general anesthesia.

EFFECT OF ACUPUNCTURE COMBINED WITH EPIDURAL ANESTHESIA ON PLASMA CATECHOLAMINE CONTENT IN CHOLECYSTECTOMY PATIENTS

Objective: To observe changes of plasma catecholamine (CA) level in patients experiencing cholecystectomy under acupuncture anesthesia combined with epidural administration of small dose of anesthetics. Methods: 33 cholecystectomy patients were randomly divided into acupuncture combined with epidural anesthesia (A) group (n=11), acupoint skin electrical stimulation combined with epidural anesthesia (B) group (n=11) and simple epidural anesthesia (C) group (n=11). Acupoints used were bilateral Zusanli (ST 36) and Neiguan (PC 6) and stimulated with parameters of frequency 2/15 Hz, intermittent waves, electric current 2～3 mA for group A and 13mA for group B. Extradural anesthetic administered was 1.5% Lidocaine 5 mL. Venous blood samples were collected one day before, during and 3 days after operation for detecting plasma NE, E and DA contents. Results: ① During operation, plasma NE of group A and B lowered in comparison with pre operation, particularly group A (P<0.01), while in group C, plasma NE level increased slightly; plasma E of group A and B increased significantly compared with pre operation (P< 0.01). Plasma DA in the 3 groups all raised during operation. ② Three days after operation, plasma NE, E and DA levels recovered basically in comparison with those of one day before operation. It indicates that acupuncture or acupoint skin electrical stimulation is capable of regulating sympathetic activity during epidural anesthesia. The anesthetic effect has a closer relation with changes of plasma NE level rather than changes of plasma E or DA levels. Conclusion: Acupuncture or acupoint surface electrical stimulation combined with epidural anesthesia may be of reducing or releasing surgical operation generated stress response during cholecystectomy.