Reperfusion of skeletal muscle after warm ischemia

The effect of 2 to 10 hours of tourniquet ischemia on the microcirculation of the tenuissimus muscle in 29 cats was studied by in vivo microscopy and electron microscopy. After release of the tourniquet there was immediate reperfusion and hyperemia in all muscles. Arterioles of 20 micron increased in diameter by 50% and venules of 35 micron by 30%. If the ischemia had lasted for 8 hours or more, reocclusion of flow occurred after 3 to 55 minutes. Platelet thromboembolism, sticking of leukocytes, and red cell aggregation seem to cause the occlusion.