Abstract
It has been well known that one of most rapid and efficient method for complete paralysis in whole arm is to inflate a tourniquet, which is positioned on the arm proximal to the axilla (Goodwin et al., 1972). This method may have direct effects on the distal motor organs, but also on the central neuronal system. Somatosensory evoked potentials (SEP) is one of useful techniques to detect the influence on the somatosensory system. However, there are very few previous studies which focused on the influence of arterial occlusion on SEP to median nerve stimuli. In the present study, we investigated the SEP to median nerve stimuli during the arterial occlusion.Ten right-handed volunteers (seven men and three women, 19-22 years old) with no history of neurological or other disease participated in the study. The SEP to right median nerve stimuli delivered at a rate of five per second was recorded during rest (control condition) and during vascular occlusion at a pressure of 250 mmHg applied by at a tourniquet to the proximal end of the upper arm (experimental condition). Each length of control and experimental conditions was 120 s. Although no significant change was observed in the amplitudes of Erb’s potential and N13, that of N20 significantly decreased during arterial occlusion (p<0.01) with the enhanced sensitivity of the thenar eminence muscle to median nerve stimuli. These results suggest that the transient, arterial occlusion around the upper arm will induce attenuation of the function in the median nerve. [Jpn J Physiol 55 Suppl:S166 (2005)]
