Clinical Study On Electrical Stimulation Threshold Of Sciatic Nerve In Diabetic Patients

Objective To investigate the effect of diabetic peripheral neuropathy and its severity on the threshold of sciatic nerve electrical stimulation,we measured the sciatic nerve electrical stimulation threshold of diabetic during sciatic nerve block,by using real-time ultrasound guidance and combine with nerve electrical stimulation.Methods From March 2019 to October 2019,60 patients underwent electi-ve surgery for lower extremity surgery and sciatic nerve block in the First Affili-ated Hospital of Guangxi Medical University were selected,including 26 non-d-iabetic patients（group ND）and 34 diabetic patients（group D）,whose age were22⁸3 years.Patients were screened for diabetic peripheral neuropathy using the Toronto Clinical System Scoring System（TCSS）the day before operation.According to the screening results,diabetic patients were divided into diabetic peripheral neuropathy group（D₁group）and no peripheral neuropathy group（D₀group）.During ultrasound combined with nerve stimulator guided popliteal sciatic nerve block,the sciatic nerve was stimulated with a low-intensity（less than 3m A）,short-time（0.1ms）current（frequency 1Hz）through an insulated electrical stimulation needle.Before injection of local anesthetics,we recorded the minimum current required to produce motor activity for sciatic nerve.Comp-ared the sciatic nerve electrical stimulation threshold among patients in each group,and analyzed the relationship between threshold of electrical stimulation of sciatic nerve and the score of diabetic peripheral neuropathy.Results The results of screening for peripheral neuropathy in the diabetes patients showed that there were 8 patients without peripheral neuropathy,7 had mild peripheral neuropathy,11 had moderate peripheral neuropathy and 8 had severe peripheral neuropathy,respectively.All of non-diabetic patients had no pe-ripheral neuropathy.The average electrical stimulation threshold（1.04±0.71m A）of diabetic patients（n=34）was significantly higher than that of non-diabetic pat-ients（n=26）（0.41±0.09m A）,the difference was statistically significant（P<0.05）.Diabetic patients with peripheral neuropathy had a higher electrical stimulation threshold（1.23±0.71m A）than patients without peripheral neuropathy（0.41±0.08m A）.However,there was not statistically different between the electrical stimulation threshold（0.41±0.08m A）of diabetic patients without peripheral neuropathy and non-diabetic patients（0.41±0.09m A）.Furthermore,the electric-al stimulation threshold of sciatic nerve in diabetic patients has a linear depende-nce on the score of peripheral neuropathy.The electrical stimulation threshold（m A）=0.325+0.112×TCSS,P<0.001.Conclusion The sciatic nerve current stimulation threshold of diabetic pa-tients with peripheral neuropathy is higher than that of non-diabetic patients,and the threshold of electrical stimulation of sciatic nerve increases with the severity of diabetic nerve dysfunction.