Severe contusion of the femoral vessels in rats alters tissue oxygenation and microvascular blood flow regulation in the skeletal muscles of the limb

Background: Severe contusion of an artery often presents clinical problems in that it affects flow distal to the injury. However, the effect of a cont usion on the microvascular flow regulation in the distal part of the limb i s still largely unknown. Methods: A multipoint microelectrode technique was used to assess both tiss ue oxygenation (P(t)o(2)) and microflow (hydrogen clearance) on the skeleta l muscle surface in a standard contusion injury to the femoral vessels in r ats. Results: A significant increase in and an altered distribution of (P(t)o(2) ) as well as a reduction in and altered distribution of microflow on the mu scle surface distal to the injury was found in all animals (n = 27) compare d with the uninjured control leg. These findings could not be reproduced ex perimentally by sympathectomy or when the adjacent skeletal muscle alone wa s injured. Conclusion: The results suggest that the changes observed distal to the inj ury are of vascular origin, possibly as a result of endothelial damage at t he site of the contusion.