Metabolic and histologic changes in the ischemic muscles of replanted dog legs.

The sequential and histologic changes occurring in muscles from ischemia were investigated in dogs. The left hind limbs were amputated, and recirculation was established after preserving them either in ice water or at room temperature for six to 12 hours. Slight leakage of the muscle enzymes creatine phosphokinase (CPK), mitochondrial glutamic oxaloacetic transaminase (GOT-m), and lactate dehydrogenase (LDH) into the recirculated venous blood occurred in specimens preserved in ice water for six hours, but there was a marked increase in enzyme leakage in the other groups. Histologic muscle changes consisted of cell swelling and separation of the sarcoplasm from the endomysium. Electron microscopy revealed widening of the myofibrillar spaces, a virtual absence of glycogen granules, and degeneration of mitochondria. These results support the clinical practice that the amputated extremities must be preserved in ice water and that blood recirculation should be initiated within six hours of amputation.