The effect of acupressure at the extra 1 point on subjective and autonomic responses to needle insertion.

BACKGROUND Premedication with sedatives can decrease the discomfort associated with invasive anesthetic procedures. Some researchers have shown that acupressure on the acupuncture extra 1 point is effective for sedation. We investigated whether acupressure on the extra 1 point could alleviate the pain of needle insertion. METHODS We investigated the effect of acupressure at the extra 1 point or a sham point on needle insertion using verbal rating scale (VRS) pain scores and heart rate variability (HRV). Twenty-two healthy female volunteers were randomly allocated to two groups: the extra 1 group received acupressure at the extra 1 point, and the sham group received acupressure at a sham point. After starting the electrocardiogram record, a 27-gauge needle was inserted into the skin of a forearm. Thereafter, another needle was inserted into the skin of the other forearm during acupressure. RESULTS Acupressure at the extra 1 point significantly reduced the VRS, but acupressure at the sham increased the VRS. Acupressure at the extra 1 significantly reduced the low frequency/high frequency ratio of HRV responding to needle insertion. CONCLUSIONS Acupressure at the extra 1 point significantly reduced needle insertion pain compared with acupressure at the sham point. Also, acupressure at the extra 1 point significantly reduced the low frequency/high frequency ratio of HRV responding to needle insertion, which implies a reduction in sympathetic nervous system activity.