This study was performed to clarify whether local anesthesia or sympathetic ganglion block abolishes the effects of electrical acupuncture (EA) on the autonomic nervous system or not.
Twelve healthy adult volunteers and 24 patients are divided into the following three experimental groups of each 12. EA was performed to the traditional acupuncture points on the meridians (H7; SHENMEN and CX4; HSIMEN). (1) In control group, only EA was performed. (2) In stellate ganglion block (SGB) group, EA was performed after unilateral SGB. (3) In local anesthesia (LA) group, EA was performed after local anesthesia on the same acupuncture points. The measured parameters on the autonomic nervous system functions were heart rates, R-R intervals in ECG, blood pressure and deep tissue temperature.
Results are as follows; Means of heart rate decreased significantly by EA in both control and SGB groups. Systolic blood pressure, diastolic blood pressure and RR-CV showed no significant changes by EA in all groups. Deep tissue temperature of the anterior forearm ipsilateral to the stimulation side decreased significantly by EA in SGB group. Deep tissure temperature of the anterior forearm contralateral to the stimuli decreased significantly by EA in both control and SGB groups. In LA group, however, all parameters were not changed by EA.
In summary, the effects of electrical acupuncture on the autonomic nervous system were not much different between control and SGB groups. It seems that one side of stellate ganglion block dose not interfere with the effects of acupuncture. On the other hand, any changes on the autonomic nervous system by electrical acupuncture were not observed in LA group. The fact showed that local anesthesia abolishes the effects of acupuncture on site. Local anesthesia blocks peripheral nerves and nerve endings. Therefore, we conclude that the effects of acupuncture on the autonomic nervous system are transmitted through the peripheral nerves, especially through the sensory nerves.