Differences of regional blood flow after stellate ganglion block with local anesthetic and that after stellate ganglion resection using ultrasonic Doppler flowmeter]

Ten mongrel dogs were divided into two groups; stellate ganglion block (SGB, n = 5) group and stellate ganglion resection (SGR, n = 5) group. Anesthesia was induced with pentobarbital 25 mg.kg-1. The animals were mechanically ventilated to maintain a constant PaCO2 (35-40 mmHg). Left common carotid arterial flow (CCAF), left external carotid arterial flow (ECAF), left vertebral arterial flow (VAF) and left brachial arterial flow (BAF) were measured using an ultrasonic transit time flowmeter. Internal carotid arterial flow (ICAF) was calculated by subtracting ECAF from CCAF. After thoracotomy, the first SGB with 0.5% mepivacaine 1.5 ml or SGR was performed. Ninety minutes after the first SGB, the second SGB was performed. The data were taken for 180 minutes after the first SGB or SGR. In SGB, CCAF and BAF increased significantly for the duration of action of local anesthetic. But VAF and ICAF increased significantly for a short time after the block. In SGR, CCAF, BAF and ICAF increased significantly during the experiment. But VAF showed a transitory increase immediately after the resection. The authors conclude that sympathetic ganglion block with local anesthetic should be performed repeatedly when increase of blood flow in blood vessels with strong autoregulation from the brain is anticipated.