[Study on the inflation pressure of air tourniquets in surgery of the upper extremities].

52 patients were studied under two different inflation pressure so as to find out the proper inflation pressure in the upper extremity operation. Analyzing the hemostasis effect and EMG of the upper extremity under different inflation pressre, it suggested that when the air tourniquet is used in the upper extremity operation the traditionally used pressure (33.3-40.0 kPa) of the air tourniquet should be changed according to the patient's condition. Usually good hemotasis effect could be obtained under the pressure of 4.0-6.6 kPa, which is more than the systolic pressure of the brachial artery.