Background: Lung injury may occur after the surgical procedures involving the temporary aortic occlusion with subsequent ischemia reperfusion of the lower extremities. Activation of the polymorphonuclear neutrophils is known to play an important role in the pathophysiologic mechanisms. The aim of this study was to determine whether the aprotinin which is a protease inhibitor could have a protective effect on this injury.

Methods: A rabbit model in which the infra renal aorta was encircled with median laparotomy and occluded for 3 hours followed by 1 hour of reperfusion was used. New Zelland white rabbits of both sex were randomised into 3 groups. Aprotinin was given 30,000 KIU as a bolus after the induction of anestesia in Group 1 (n = 12), similar volume of saline solution was used in Group 2 (n = 12). Group 3 of animals (sham group, n = 12) were anesthetized and subjected to the surgical procedures without aortic occlusion. At the end of 1 hour reperfusion, arterial blood gases were measured and the rabbits were sacrificed. The lungs were histologically examined and scored according to evidences of the injury.

Results: The average pO2 in the Group 2 was significantly lower than in the other groups (p < 0.05). No pathologic finding in lung histology was noted in the Group 3 of animals. The animals of Group 2 exhibited significantly higher lung inflammation than the animals of Group 1 (p < 0.05).

Conclusion: The results suggest that aprotinin reduces the lung injury caused by ischemia-reperfusion of the lower extremities.

Keywords : Lower extremity, ischemia, reperfusion, lung injury, aprotinin