Effect of surface spinal stimulation on autonomic nervous system in the patients with spinal cord injury

Background: The Autonomic Nervous System (ANS) plays a key role in the regulation of many physiological processes, mediated by supraspinal control from centers in the central nervous system. Spinal cord injury (SCI) decreases the ability to sympathetically control blood pressure and to regulate body temperature. Bladder dysfunction has been reported as a serious medical complication following SCI. The purpose of study is to find the effect of surface spinal stimulation on autonomic nervous system i.e., bladder function, skin resistance, and skin temperature. Materials and Methods: Five traumatic spinal cord injury subjects were selected for experimental pilot study; surface spinal stimulation for 45 minute period applied to the skin in T11-L2 area, with a carrier frequency of 2500Hz and modulated to beats frequency of 20Hz. Stimulation amplitude was raised to cause sensory stimulation. The pre- and post-stimulation values using the values of urodynamics testing, galvanic skin response, and infra-red thermometer compared in same patients and results were obtained. Results: Result of the present study indicates that four of five subjects demonstrate a decrease in the infused fluid volume, improved bladder sensation, but shown no effect over the bladder capacity. The skin resistance of the right lower limb was increased post-stimulation, but the improvement was not significant, and skin temperature of thigh and foreleg improved significantly. Conclusion: According to our results, surface spinal stimulation was effective to improve non-reflexive bladder, skin resistance and skin temperature, but further research is needed