Efficacy of thoracic sympathetic ganglion block and prediction of complications: clinical evaluation of the anterior paratracheal and posterior paravertebral approaches in 234 patients.
In the 10 years from 1980 to 1989, a total of 234 patients underwent 557 thoracic sympathetic ganglion blocks. The block was performed by the anterior paratracheal approach in 129 cases and by the posterior paravertebral approach in 428 cases. The procedures for using these two approaches are presented here. The efficacy of thoracic sympathetic ganglion blockade was evaluated as follows; marked efficacy was defined by the complete control of sweating in the palms, moderate efficacy was defined by a decrease in palmar sweating which persisted for at least one week, and minor efficacy was defined by a decrease in sweating followed by recurrence of hyperhidrosis within one week with maintenance of palmar warmth. in addition, the results were retrospectively reviewed in relation to the age and sex of the patients, the technique used, the laterality of the block, the disease treated, the doses of local anesthetic and neurolytic agents, and the number of blocks. The posterior approach was significantly more successful than the anterior approach, and the treatment of both T2 and T3 by the posterior approach was significantly more effective than the treatment of either nerve alone by the same approach ( P < 0.01). The efficacy rate was significantly lower for hyperhidrosis than for the other diseases ( P < 0.01). Complete cessation of hyperhidrosis was significantly less common in the over-60 age group ( P < 0.01). Regarding the dose of neurolytic, the complete cessation of hyperhidrosis was achieved significantly more frequently with doses of 2.5 ml or higher than with lower doses ( P < 0.01) when both T2 and T3 wee treated by the posterior approach. A dose-dependent response if hyperhidrosis was noted at dose levels higher than 2.5 ml. Thoracic sympathetic ganglion blockade was only occasionally associated with complications, and no serious complications were observed. Before injecting the neurolytic agent, a mixture of contrast medium and local anesthetic was injected to determine the three-dimensional distribution of the contrast and to assess the scope of the analgesia produced by the local anesthetic. Significant complications could thus be avoided.