The effect of ulinastatin on reduced nerve conduction velocity and blood pressure.

Application of a pneumatic tourniquet in orthopedic surgery is sometimes followed by hypotension and paralysis. Seventy-five patients scheduled for knee joint surgery were examined to evaluate the effects of ulinastatin on changes in blood pressure, venous pH and motor nerve conduction by pneumatic tourniquet application above the knee joint. In fifty-five of the patients, the femoral vein of the operating side was cannulated with a catheter to obtain venous blood samples before and after tourniquet application. 300,000 Unit of ulinastatin (UST) was administered intravenously before inflation of the tourniquet in 10 patients. In the other sixteen patients, the motor nerve conduction velocity (MNCV) of the peroneal nerve was measured before inflation and after release of the tourniquet. In the UST-free group, the reduced blood pressure and pH persisted for more than 15 min, while in the UST-treated group, the reduced blood pressure returned to the normal leven in 15 min. In the control group, femoral venous P(O)(2) continued to increase after 10 min, but that in the UST-treated group returned to the normal range. Tourniquet application significantly reduced peroneal MNCV. Pre-and post-treatment with UST significantly lessened the reduction of MNCV induced by the tourniquet. It is concluded that UST may have protective and therapeutic effects on ischemic nerve injury, induced by the application of a turniquet.