Review of transcutaneous electrical acupoint stimulation and related devices

A review was undertaken of the operation process and development of transcutaneous electrical acupoint stimulation(TEAS)and related devices for TEAS,with the aim to offer a reference for developing an international standard for the basic safety and essential performance of the devices.The articles related to TEAS and instruction of devices for TEAS were searched using the EMBASE,MEDLINE,and Web of Science databases with the time period from inception to July 18,2023.In the absence of a parameter description of the stimulators,a multimeter was used to measure the output voltage,resistance,and current.Thirty-two related devices for TEAS were obtained.The safety parameters ofmost devices were neither clearly defined,nor standardized,and in some cases weremissing.There was a noticeable disparity in the upper safety limits of the output current among the devices.The sizes of the skin electrode pads as well as the lengths of the electrode connecting wires of most devices were not clearly indicated.Acupoints on different parts of the human body,including the upper limbs,head,auricle,chest,abdomen,trunk,and lower limbs,required different maximum tolerable current intensities and current densities.It is important to indicate comprehensive output/safety parameters and essential performance for devices for TEAS to meet the need of global distribution,achieve precise stimulation parameters at different acupoints across the human body,and allay any safety concern of national therapeutic device authorities,the regulators,manufacturers,and end users.

Capillary blood flow in patients with dysmenorrhea treated with acupuncture

OBJECTIVE: To observe capillary blood flow at acupoints during acupuncture treatment of primary dysmenorrhea and gain new insights into its analgesic mechanism. METHODS: Patients with primary dysmenorrhea were enrolled and randomly assigned to a treatment or control group. Subjects' symptoms were differentiated into variousTraditional Chinese Medicine(TCM) syndromes and treated for 10 sessions with puncturing acupuncture or self-pressing right-hand Hegu(LI 4), adding other acupoints based on syndrome. Laser speckle was used to compare the change in the vasomotor amplitude and perfusion of the capillaries in Hegu(LI 4) before and during the treatment. Each subject was required to finish the period pain symptoms observation form, verbal rating scales, numerical rating scale, pain rating index, face rating scale, Zung self-rating depression scale, Zung self-rating anxiety scale, and numerical rating scale before and after treatments. RESULTS: After 10 sessions, the symptom scores, pain index(PI), and visual analog scale(VAS) decreased significantly in treatment group. The volume of blood flow in Hegu(LI 4) declined slightly. No significant evidence supported that needling caused capillary contraction, but the capillary vasomotor amplitude at Hegu(LI 4) increased remarkably. CONCLUSION: Acupuncture can increase the capillary blood flow, thus promoting the flow of Qi and blood in terms of TCM theory, which facilitates pain relief.