RESUMO
OBJECTIVE: To observe the effects of transcutaneous electrical acupoint stimulation (TEAS) at different times on the stress response during anesthesia and operation in the patients undergoing open posterior lumbar surgery. METHODS: A total of 94 patients undergoing open posterior lumbar surgery were randomly assigned to preoperative TEAS group(32 cases), intraoperative TEAS group(31 cases) and sham-TEAS group(31 cases). The same anesthetic method was used in the patients of 3 groups. Four electrodes were attached to the bilateral Hegu (LI4) and Neiguan (PC6) and connected to the electronic acupuncture instrument when patients entered the operation room. In the preoperative TEAS group, the patients received TEAS (10 to 20 mA) for 30 min before the anesthetic induction. TEAS (15 mA) was provided immediately when the operation starts till the end of ope-ration for the patients of the intraoperative TEAS group. In the sham-TEAS group, the electronic acupuncture instrument was switched on during the whole procedure of operation, but no electric current was output. Separately, at the moment of entering the operation room (T0), before endotracheal intubation (T1), at the time of endotracheal intubation (T2), 10 min after skin resection (T3), at the end of surgery (T4), recovery from anesthesia (T5) and at the time of extubation (T6), the heart rate (HR) and mean arterial pressure (MAP) were recorded. Using ELISA, the concentrations of epinephrine (E), norepinephrine (NE), dopamine (DA), cortisol (Cor) in serum were assayed at T0, T3, and T4; and blood glucose was tested with blood sugar paper at the same time points. RESULTS: Compared with T0 of the same group, HR was increased at T2 and decreased at T3 of the patients in the sham-TEAS group and the intraoperative TEAS group (P<0.05). Compared with the sham-TEAS group at the same time points, HR was decreased at T2 and increased at T3 of the patients in the preoperative TEAS group (P<0.05), and it was decreased at T6 of patients in the intraoperation TEAS group (P<0.05). HR was reduced at T2 in the preoperative TEAS group when compared with the intraoperative TEAS group. Compared with T0 of the same group, MAP was elevated at T2 and reduced at T3 and T4 in the sham-TEAS group (P<0.05); it decreased at T3, T4 and T5 in the preoperative TEAS group (P<0.05); it rose at T2 and was reduced at T3, T4 and T5 in the intraoperative TEAS group (P<0.05). When compared with the sham-TEAS group at the same time points, MAP decreased at T2 in the preoperative TEAS group (P<0.05), and at T6 in the intraoperative TEAS group (P<0.05). MAP was reduced at T2 and elevated at T6 in the preoperative TEAS group in comparison with the intraoperative TEAS group (P<0.05) at the same time points. Compared with T0 of the same group, the contents of E was increased at T3 in the sham-TEAS group and the intraoperative TEAS group (P<0.05); it was increased in all of the three groups at T4 (P<0.05); the contents of NE, DA, Cor and the blood glucose were increased at T4 in the sham-TEAS group (P<0.05). Compared with the sham-TEAS group at the same time points, the contents of E, DA at T3 and T4 and Cor at T3 in serum of the preoperative TEAS group were decreased (P<0.05); and the contents of E, NE, DA and Cor at T4 in the intraoperative TEAS group were decreased (P<0.05). CONCLUSION: TEAS-assisted general anesthesia can better maintain the stability of HR and MAP during anesthesia and operation in patients undergoing open posterior lumbar surgery, and reduce surgical stress response.
