One of the most promising indications for acupuncture is to prevent postoperative nausea and vomiting (PONV). PONV results in patient dissatisfaction, delayed discharge, unanticipated hospital admission, and the use of resources. Drugs have been the mainstay of management, however these have limited effectiveness, are associated with adverse effects, and can be costly.
Acupuncture prevents PONV compared with sham acupuncture or no treatment.In two early controlled trials, acupuncture prevented PONV in the pediatric population; however, one literature review of 10 research studies examining the use of acupressure and acupuncture in adults concluded that it is not effective in preventing and managing PONV. Other clinical studies have found that acupuncture prevents PONV and results in a greater degree of adult patient satisfaction. For many of the trials in both adults and children, the PONV acupuncture point was P6 or PC6 (i.e., Nei guan or Pericardium 6). The P6 acupuncture point is located between the palmaris longus and flexor carpi radialis muscle tendons, 4 cm proximal to the distal wrist crease and 1 cm below the skin.
Intraoperative stimulation of the P6 acupuncture point reduced the incidence of PONV, and its efficacy was similar to that of antiemetic drugs. Stimulation of the acupuncture point should be initiated before induction of anesthesia. Postoperative stimulation may be just as or more effective. In children, stimulation immediately before emergence and in the recovery room has been effective. A recent metaanalysis for pediatric tonsillectomy indicated that acupuncture at the P6 acupuncture point is effective in preventing PONV.
Some anesthesiologists anecdotally report tapping a small needle cap or other piece of smooth plastic over the P6 point as an effective means of acupressure stimulation. Studies often differ in acupuncture method: duration and timing of stimulation, unilateral versus bilateral stimulation, and type of stimulation (i.e., needles with or without additional stimulation, acupressure, transcutaneous electrical stimulation, cutaneous laser stimulation, injection of a 50% dextrose solution, or capsicum plaster). Data to compare the effectiveness, safety, and costs of different methods of stimulation are inadequate.