Effect of sympathetic auricular acupoint in orthostatic response

Objective: To elucidate the effect of auriculopuncture in Sympathetic points on autonomic function, we investigated the heart rate (HR) response to orthostatic challenge in healthy subjects. Design and setting: An experimental and cross-sectional study was conducted at Acupuncture Clinic, Universidad Autónoma Metropolitana, and México. Participants. Twenty healthy university students (twelve women) aged 22.7 ± 1.5 (mean ± SD) participated in the study. Interventions and outcomes: The study consisted of two sessions of auricular acupuncture in the Sympathetic point in the right or left ear. The data for continuous normal beat-to-beat recording to derive the statistical parameters of the normal R-R intervals of the electrocardiogram was obtained using the SphygmoCor equipment (AtCor Medical Pty Ltd, Sidney, Australia). The registration periods were computed in a supine position and then after standing. The primary outcomes were the changes in the velocities of the primary HR increase, bradycardia secondary response, and interval between the times of maximum increase in HR and minimum in secondary response. Results: Acupuncture at the Sympathetic point in the right ear raises the velocity of the initial HR increase and decreases the velocity of bradycardia secondary response and elicits a shortening of the period between the maximum increase and minimum in the secondary response in HR, in all cases significant. Otherwise, auriculopuncture in the Sympathetic point of the left ear did not produce significant changes in the outcomes studied. Conclusion: Data suggest that auriculopuncture in the Sympathetic right point elicits a vagal suppression in the initial orthostatic response to active standing.