To the Editor:—
Dr. Rusy et al. are to be congratulated for publishing an article as timely as it is courageous concerning electroacupuncture at P6 (A.K.A. Master of the Heart-6, MH6) for prophylaxis of nausea and emesis in children after tonsillectomy. 1The article is timely in view of the recent FDA “black box” warning concerning droperidol, strongly discouraging its use in view of reports of QT prolongation, torsades, and death. The article is courageous in evaluating a treatment some physicians regard with skepticism. The article concludes electroacupuncture at MH6 reduces the feeling of nausea but that the effect may not be powerful enough to reduce the incidence of vomiting after tonsillectomy. The study found no reduction in the incidence of vomiting or need for rescue medications. In view of these results, the authors do not support the use of acupuncture in lieu of prophylactic intravenous antiemetics. Before condemning a therapy, however, it is essential to scrutinize the methodology employed in its evaluation.
In patients under a general anesthetic, after removal of the second tonsil, acupuncture needles were inserted at the MH6 acupuncture point to a depth of 1 cm in all patients. Aside from the placement 2 cuns above the wrist crease between the flexi carpi radialis tendon and the tendon of the palmaris longus, no other method was apparently employed to ascertain correct location and depth of placement. Many acupuncture practitioners will slowly advance an acupuncture needle with gentle rotation until a De Qi or “arrival of Qi” sensation is appreciated by a patient as a “muscular ache” and by practitioner as a “needle grab” by muscle. In fact, some authorities feel that a needle must be advanced to a depth where De Qi is experienced for atreatment to be effective. 2I was curious whether the investigators employed such a technique to help insure proper needle placement, and how the standard depth of 1 cm was determined. Median nerve discharge is common with needle placement at MH6, and may be extremely uncomfortable in an awake patient.
While the MH6 acupuncture point has been most extensively studied for PONV, it seems odd that a point classically used for cardiac or respiratory disorders that is the special command point for the thorax 3should receive such singular attention in nausea. Certain points along the stomach meridian may hold greater promise in this regard. Stomach-36 (ST-36), for example, which is the special command point for the abdomen, 4located 3 cuns distal to the inferior border of the patella and a finger-breadth lateral to the tibial tuberosity is one of the four strongest acupuncture points on the body and may be used to treat nausea. Stomach-43 (ST-43) located on the dorsum of the foot in the second interosseus space is also promising. The combination is likely to be superb. There are, at present, no published reports evaluating the efficacy of these points for PONV.
The investigators may be correct that electroacupuncture at MH6 lacks sufficient potency to prevent postoperative emesis. It is encouraging that the therapy reduces the incidence of nausea. Further study of more potent acupuncture points that are more closely related to the problem at hand may yield more favorable results.