To the Editor
In a recently published trial by White et al.,1 the use of the Pressure Right® (Pressure Point Inc., Grand Rapids, MI) P6 acupoint stimulation strips in concert with antiemetic drug therapy was shown to improve patient satisfaction with the management of postoperative nausea and vomiting (PONV). They suggested that these noninvasive devices may be a useful adjunctive therapy in preventing PONV. Our institution recently began prophylactically applying these devices on patients having a history of PONV. We describe a case of transient median neuropathy which may have been related to the use of this device.
A 24-year-old woman with a body mass index of 29 kg/m2 underwent a 6-hour maxillary reconstruction surgery to correct a facial deformity. Acupoint stimulation strips were applied preoperatively to both forearms. To facilitate surgical exposure, her arms were adducted, wrapped in gel pads, and then tucked along the body. Only 1.25 L of lactated Ringer’s solution was administered. Postoperatively she complained of hypesthesia of the thumb, index, and middle finger of the palmar surface of the right hand in the median nerve distribution. These symptoms resolved after 4 days.
As a part of treatment, a plastic button is firmly placed on the P6 acupoint which lies over the median nerve proximal to the carpal tunnel (Fig. 1). We believe that in this case, tucking the arms applied additional force to the buttons and combined with the prolonged surgery, may have been sufficient to cause a compression injury to the median nerve. Median nerve injuries can occur with traditional acupuncture,2,3 but have not been previously reported along with the use of the acupressure devices. To mitigate the rate of positioning injuries, our practice emphasizes proper arm positioning, tucking, and padding. This includes attention to “hard” objects that come in contact with the patient such as IV line connectors and ports, which we feel could cause focal compression injuries in a tucked arm. Such objects are either removed or well padded before the arm is tucked. In light of this median nerve injury encountered with the use of a P6 acupoint stimulation strip, these authors now view the plastic button as a hard object and have opted to eliminate the use of these devices when arms are to be tucked.
William B. Beam, MD
Toby N. Weingarten, MD
Juraj Sprung, MD, PhD
Department of Anesthesiology
Mayo Clinic College of Medicine
1. White PF, Zhao M, Tang J, Wender RH, Yumul R, Sloninsky AV, Naruse R, Kariger R, Cunneen S. Use of a disposable acupressure device as part of a multimodal antiemetic strategy for reducing postoperative nausea and vomiting. Anesth Analg. 2012;115:31–7
2. Southworth SR, Hartwig RH. Foreign body in the median nerve: a complication of acupuncture. J Hand Surg Br. 1990;15:111–2
3. Lee CH, Hyun JK, Lee SJ. Isolated median sensory neuropathy after acupuncture. Arch Phys Med Rehabil. 2008;89:2379–81