Effect of electroacupuncture on adrenocortical function under etomidate-based anesthesia

Objective To investigate the effect of electro-acupuncture on adrenocortical function under etomidate-based anesthesia in patients.Methods Eighty ASA physical status Ⅰ or Ⅱ patients of both sexes,aged 30-64 yr,scheduled for elective abdominal surgery,were randomly divided into 4 groups (n =20 each):propofol control group (group P),etomidate group (group E),etomidate + electro-acupuncture group (group EEA),and etomidate + sham electro-acupuncture group (group ES).Anesthesia was induced with midazolam,etomidate,sufentanil and atracurium in E,EEA and ES groups,or with midazolam,propofol,sufentanil and atracurium in group P.The patients were mechanically ventilated after endotracheal intubation.Anesthesia was maintained with iv infusion of etomidate and remifentanil and intermittent iv boluses of atracurium in E,EEA and ES groups,or with iv infusion of propofol and remifentanil and intermittent iv boluses of atracurium in group P.Electro-acupuncture stimulation of Zusanli and Sanyinjiao (frequency 2 Hz /50 Hz,wave length 300 μs) was started from the time before induction of anesthesia and continued until the end of surgery in group EEA.Venous blood samples were taken before induction of anesthesia (T0),at 2 h after beginning of surgery (T1),at the end of surgery (T2) and at 2 h after surgery (T3) for determination of serum cortisol,adrenocorticotropic hormone (ACTH),epinephrine and norepinephrine concentrations.Results Compared with group P,the serum cortisol concentrations were significantly decreased at T1-3,the serum ACTH concentration was increased at T3 in groups E,EEA and ES,and the serum epinephrine levels at T1,2 and norepinephrine levels at T1-3 were decreased in group EEA (P ＜0.05).Compared with group E,the serum cortisol concentrations were significantly increased at T1-3,the serum ACTH concentration was decreased at T3,and the serum epinephrine levels at T1,2 and norepinephrine levels at T1-3 were decreased in group EEA (P ＜ 0.05),and no significant change was found in the parameters mentioned above in group ES (P ＞ 0.05).Conclusion Electro-acupuncture can mitigate etomidate-based anesthesia-induced inhibition of adrenocortical function in patients. Key words: Electroacupuncture;  Etomidate;  Adrenal cortex function tests