Optimal dose of dexmedetomidine combined with propofol for anesthesia in patients undergoing modified electroconvulsive therapy / 中华麻醉学杂志

ABSTRACT

Objective:To investigate the optimal dose of dexmedetomidine combined with propofol for anesthesia in patients undergoing modified electroconvulsive therapy (MECT).Methods:One hundred and sixty patients of both sexes, aged 20-60 yr, weighing 45-80 kg, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, scheduled for elective MECT, were allocated into 4 groups ( n=40 each) by a random number table method: different doses of dexmedetomidine combined with propofol group (D 1, D 2 and D 3 groups) and routine anesthesia group (group C). Dexmedetomidine 0.2, 0.4 and 0.6 μg/kg were intravenously injected in D 1, D 2 and D 3 groups, respectively, the equal volume of normal saline was given instead in group C, and propofol 1.0 mg/kg and succinylcholine 0.5 mg/kg were intravenously injected in turn 10 min later.Venous blood samples were collected before giving dexmedetomidine (T 0) and at 1 min after the end of MECT (T 1) for determination of the plasma epinephrine (E) and norepinephrine (NE) concentrations.Propofol consumption, occurrence of cardiovascular events, duration of epilespsy and energy suppression index were recorded. Results:Compared with group C, the plasma E and NE concentrations were significantly decreased at T 4, and the propofol consumption was reduced in D 1, D 2 and D 3 groups ( P<0.05). Compared with group D 2, the plasma E and NE concentrations were significantly increased at T 1 in group D 1 and decreased at T 1 in group D 3 ( P<0.05). The incidence of adverse cardiovascular events was significantly increased in group D 3 than in the other 3 groups ( P<0.05). There was no significant difference in duration of epilespsy or energy suppfession index among the 4 groups( P>0.05). Conclusion:The optimal dose of dexmedetomidine combined with propofol 1.0 mg/kg is 0.4 μg/kg when used for anesthesia in the patients undergoing MECT.