[Influence of stellate ganglion block and electrical stimulation of the stellate ganglion on bilateral brachial arterial blood flow--is stellate ganglion block effective either unilaterally or bilaterally?].

The purpose of this study was to investigate the influence of the stellate ganglion block (SGB), stellate ganglion electrical stimulation (SGES) and stellate ganglionectomy on bilateral arterial blood flows (BAF). Sixteen mongrel dogs were divided into two groups; a SGB group (n = 8) and a SGES group (n = 8). Anesthesia was induced with pentobarbital 25 mg.kg-1 and the animals were mechanically ventilated to maintain proper PaO2 (90-100 mmHg) and PaCO2 (35-40 mmHg). After a thoracotomy, the SGB with 0.5% mepivacaine 1.0 ml was performed in the SGB group. SGES was performed at a strength of 12 volts, and at a frequency of 50 Hz, applied for 15 minutes and then 15 minutes after the SGES, stellate ganglionectomy was performed in SGES group. In the SGB group, BAF in the blocked side increased significantly but BAF in the contralateral side decreased significantly after SGB. In the SGES group, bilateral BAF decreased significantly (Lt > Rt) and after the stellate ganglionectomy, bilateral BAF increased more than after SGES. These results suggest that the SGB may not be effective on the contralateral side under normal conditions, but under the conditions of sympathetic stimulation, the SGB may be effective on the contralateral side.