| 摘要 |
PROBLEM TO BE SOLVED: To permit a system to be used by a patient having a buried-type electronic device, to be small and inexpensive, to be used singly and sterilization possible and to be used by only one engineer. SOLUTION: A needle assembly 12 is included and the needle assembly is provided with a conductive needle canula 20, a non-conductive tube 28 fixed to it and a conductive plating 36 on the tube. A conductor is connected to a stimulator 14 which generates a high charge pulse and a low charge pulse which are changed by a fixed current level. The high charge pulse causes remarkable muscle contraction immediately after a needle is inserted to the patient. The extent of muscle contraction which responds to the high charge pulse becomes a peak, muscle contraction which responds to the low charge pulse becomes observation possible as the needle approaches to a nerve to be a target and it becomes discrimination impossible from muscle contraction which responds to the high charge pulse when the needle is positioned for giving a narcotic. |
