Background: Acute transient aortic occlusion with subsequent ischemia/reperfusion (IR) of the lower extremities is known to predispose to the lung injury characterized by inflammation and interstitial edema. In this study, we aimed to investigate whether normovolemic hemodilution by ringer lactate (RL) could have any beneficial effect on the lung injury caused by IR of the lower extremities.

Methods: Thirteen wistar albino male rats were used for the study. A rat model in which bilateral lower extremities were tightened by plastic tourniquet for ischemia of 2 hours and then loosened for reperfusion of 3 hours were used as an experimental model. Ischemia/reperfusion of the lower extremities were performed in group of IR (group I, n=6) without hemodilution and in group of RL (group II, n=7) after hemodiluted with ringer lactate solution. At the end of the experiment, the rats were sacrificed by an intravenous overdose of pentobarbital sodium. The lungs were histologically examined. Lung injury was rated with a semiquantitative score based on congestion, interstitial edema, PMN infiltration and airspace hemorrhage, as follows: 0+, no changes; 1+, focal, mild, subtle changes; 2+, multifocal mild changes; 3+, multifocal prominent changes; 4+, extensive prominent changes. Student's t-test and Mann-Whitney U-test were used for statistical analysis.

Results: Mean Hct. value were %48.2±1.7 and %35.1±0.9 in group I and II respectively (p<0.001). The lung injury score after IR of lower extremities in rats were significantly higher in group I (mean 3±0.63) than group II (mean 1.42±0.53) (p<0.05).

Conclusion: Normovolemic hemodilution reduces the lung injury caused by IR of the lower extremities.

Keywords : Ischemia/reperfusion; normovolemic hemodilution; lung injury