Low reactive-level laser irradiation on the stellate ganglion in dogs.

The aim of this study was to determine what effects low reactive-level laser irradiation (LLLI) of the stellate ganglion might have on the sympathetic fibers of the stellate ganglion in dogs. Following general anesthesia, the right stellate ganglion was exposed by thoracotomy. After stabilization, the following baseline measurements were taken: mean arterial pressure, heart rate, and blood flow of the common carotid artery. The stellate ganglion was directly irradiated for 10 min with a low-power laser. Measurements were taken for 60 min after LLLI. Immediately after the final measurement, stellate ganglion blockade was performed with 0.5% mepivacaine 1.5 ml. Measurements were taken again 15 min after stellate ganglion blockade with a local anesthetic. The changes in each variable were not statistically significant after LLLI. On the other hand, all variables changed significantly after the stellate ganglion blockade, including increased blood flow of the common carotid artery. In conclusion, this study demonstrated that LLLI to the stellate ganglion does not cause sympathetic blockade.