Effect of Transcutaneous Acupuncture-point Electrical Stimulation (TAES) on Post-tonsillectomy Pain in Children

Abstract

S333 Although TAES has some analgesic effects on various types of pain [1], there have been few reports on magement for post-operative pain [2]. In this study we examined the effects of TAES on post-tonsillectomy pain in children. METHODS: With institutional approval and each parent's informed consent, 30 pediatric patients (4-9 years old) undergoing tonsillectomy under general anesthesia were divided randomly into TAES group (n=14) and control group (n=16). Patients were not premedicated, and induction was completed with nitrous oxide, sevoflurane (2.0-3.0 %) and oxygen. After premedication with atropine (0.01 mg/kg), tracheal intubation was facilitated with vecuronium (0.1 mg/kg). Anesthesia was maintained with sevoflurane, 1.5-2.5%, nitrous oxide, 50%, and oxygen. After anesthetic induction in TAES group, bilateral Hoku and Neikuan points of upper extremities were located with acupoint detector (Kimura Medical Co., Japan). Silver spike point electrodes were placed at 4 acupuncture sites. These electrodes were alternately stimulated by 2 Hz of bidirectional exponential waveform for 2 seconds and 20Hz of that for 2 seconds during the surgery, using TAES apparatus (ANESTY-10, Nihon Medix Co. Japan). Peak output of inpulses was 100 V. There were no other differences between groups. Any narcotics were given intraoperatively. All patients had 10 mg/kg of acetaminophen suppository given at the end of surgery for postoperative pain management. The postoperative state was assessed by the patient's parent at 30, 60 and 120 minutes after the end of surgery, using the visual facial scale (VFS) which contained 20 drawings of a single face from best mood (1 point) to worst mood (20 points). Parents were not informed of the randomization result, but were fully informed how to assess the VFS. Chi-square test, Fisher's exact probability test. Mann-Whitney test, and Wilcoxon signed rank test were used for statistical analysis and P<0.05 was considered to be significant. Data were expressed as mean +/- SE. RESULTS: There were no significant differences between 2 groups in sex, age, height, body weight, and operation time. Mean TAES time was 60 +/- 5 min. Table 1 shows the changes in VFS (Best mood; 1, Worst mood; 20).Table 1In 120 min after OP, patients with VFS scors <10 were more frequent in TAES group (8/14) than in control group (1/16). There were no complications related to TAES. CONCLUSIONS: This study indicates that TAES during general anesthesia is effective for post-tonsillectomy pain management in pediatiric patients. TAES is an useful noninvasive method. More effective stimulation methods or other stimulating points should be investigated.