Study protocol for a preliminary optimization trial of transcutaneous electrical acupoint stimulation device simulating acupuncture Deqi

Introduction: Transcutaneous electrical acupoint stimulation (TEAS) is a treatment approach derived from acupuncture but with better efficacy, safety, and non-invasiveness. It is, therefore, increasingly used in clinical practice. Traditionally, Deqi is considered a positive response of the body to acupuncture-like stimulation and essential for the efficacy of acupuncture. We hypothesized that applying array electrodes to simulate acupuncture Deqi stimulation would improve the clinical efficacy of TEAS. However, there is no comprehensive and objective method for evaluating Deqi, which may hinder the optimization of TEAS to improve its effectiveness. Therefore, objectively revealing multi-temporal dynamics of the body during the Deqi state and then screening appropriate stimulation parameters for TEAS to simulate the Deqi response is crucial for optimizing TEAS.Methods: In this self-controlled, quasi-experimental study, 30 healthy subjects will be enrolled to participate in two sections. There will be two sections in this study. The first section will puncture the "Shousanli" acupoint (LI10) with sham and verum acupuncture manipulations. Meanwhile, the electroencephalogram (EEG), electromyography (EMG), electrocardiograph (ECG), and galvanic skin response (GSR) will be recorded, and the subjective Deqi sensation questionnaire will be assessed. Then the correlation between objective signals and Deqi scores will be investigated to find the most suitable indicators that may reveal acupuncture Deqi. In the second section an array of electrodes with a similar stimulation depth of acupuncture will be used at LI10, and the appropriate rated parameters of TEAS will be determined according to the thresholds of these objective in-dicators at the state of Deqi. The primary outcomes are changes in EEG and EMG from baseline to the end of the study. Secondary outcomes include the Deqi sensation scale, ECG, and GSR. Adverse events will be recorded.Discussion: This study will be the first to apply integrated bioelectric signal technology to quantitatively assess Deqi and use it to optimize TEAS stimulation parameters. It will promote a better understanding and application of Deqi in the practice of TEAS and lay the foundation for the realization of a closed-loop feedback TEAS mode. Registration: Chinese Clinical Trial Registry, ChiCTR2200060530.