Background
Electrical stimulation of acupuncture point P6 reduces the incidence of postoperative nausea or vomiting (PONV) in adult patients. However, acupressure, laser stimulation of P6, and acupuncture during anesthesia have not been effective for reducing PONV in the pediatric population. The authors studied the effect of electrical P6 acupuncture in awake pediatric patients who had undergone surgery associated with a high incidence of PONV.
Methods
Patients aged 4-18 yr undergoing tonsillectomy with or without adenoidectomy were randomly assigned to acupuncture, sham acupuncture, or control groups. Acupuncture needles at P6 and a neutral point were placed while patients were anesthetized, and low-frequency electrical stimulation was applied to these points for 20 min in the recovery room while the patients were awake (P6 Acu group). This treatment was compared with sham needles along the arm at acupuncture points not associated with antiemesis (sham group) and a no-needle control group. The arms were wrapped to prevent identification of treatment group, and anesthetic, analgesic, and surgical technique were standardized. Assessed outcomes were occurrence of nausea, occurrence and number of episodes of vomiting, time to vomiting, and use of antiemetic rescue medication.
Results
One hundred twenty patients were enrolled in the study, 40 per group. There were no differences in age, weight, sex, or opioid administration between groups. The PONV incidence was significantly lower with P6 acupuncture (25 of 40 or 63%; odds ratio, 0.135; number needed to treat, 3.3; P < 0.001) compared with controls (37 of 40 or 93%). Sham puncture had no effect on PONV (35 of 40 or 88%; P = not significant). Occurrence of nausea was significantly less in P6 Acu (24 of 40 or 60%; odds ratio, 0.121; P < 0.01), but not in the sham group (34 of 40 or 85%) compared with the control group (37 of 40 or 93%). Vomiting occurred in 25 of 40 or 63% in P6 Acu; 35 of 40 or 88% in the sham group, and 31 in 40 or 78% in the control group (P = not significant). Patients receiving sham puncture vomited significantly earlier (P < 0.02) and needed more rescue treatment (33 of 40 or 83%; odds ratio, 3.48; P < 0.02) compared with P6 Acu (23 of 40 or 58%) and the control group (24 of 40 or 60%).
Conclusions
Perioperative P6 electroacupuncture in awake patients significantly reduced the occurrence of nausea compared with the sham and control groups, but it did not significantly reduce the incidence or number of episodes of emesis or the use of rescue antiemetics. Sham acupuncture may exacerbate the severity but not the incidence of emesis. The efficacy of P6 acupuncture for PONV prevention is similar to commonly used pharmacotherapies. Its appropriate role in prevention and treatment of PONV requires further study.