A Comparative Study of the Effect of Arterial and Venous Occlusion after Various Periods of Ischemia

ABSTRACT

The author attempted to quantify any additional tissue damage resulting from one hour of venous occlusion after controlled periods of ischemia in skeletal muscle, compared to equal time periods of ischemia. The rat quadriceps muscle was used. pH and temperature were monitored during the experiment and the damage was evaluated on histochemical sections.

Of the other two parameters monitored in this study, the pH recovery rate during reperfusion best reflected tissue perfusion and served as a predictor for the extent of tissue damage, when global ischemia or the combination of ischemia and postischemic venous stasis did not exceed five hours. Apart from the nonstained lethally damaged areas, interstitial tissue edema and cellular infiltration were constant findings in all muscles that sustained ischemia or ischemia and subsequent venous occlusion. However, both findings were more pronounced in the muscles that underwent venous obstruction. Muscle fibers were more edematous after venous occlusion, compared to ischemic muscles. Thrombosed veins and collapsed arteries, surrounded by excessive edema and inflammatory reaction, were common in muscles after ischemia and venous occlusion.

Comparing the difference in percent of lethal damage from one hour of postischemic venous stasis versus the damage from additional ischemia of equal duration, findings demonstrated comparable damage when reperfusion was established in less than five hours.