Thrombogenic stimulus causes long-term decrease of muscle flap perfusion

This study was designed to evaluate the effect of a continuous thrombogenic insult at the feeding artery on skeletal muscle flap perfusion over 24 hou rs. Twelve male Sprague-Dawley rats were divided into two experimental grou ps. In the control group (N = 6) and in the treatment group (N = 6) the rig ht cremaster muscle was isolated on its neurovascular pedicle and the tubul ar muscle flap was preserved in the medial part of the hind limb over a 24- hour period for subsequent microcirculatory observation. Un the treatment g roup, an inverting suture was applied over half of the circumference of the ipsilateral common iliac artery to create a continuous thrombogenic stimul us. Intravital microcirculatory measurements obtained were red blood cell v elocities, vessel diameters, capillary perfusion, endothelial edema index, and leukocytic-endothelial interactions. There were no statistically signif icant differences seen in red blood cell velocities, vessel diameters, and leukocytic-endothelial interactions between the groups. However, the invert ing suture caused a significant drop in capillary perfusion from 6.23 to 1. 50 capillaries per visual field (median; p = 0.002), An arterial thrombogen ic insult may result in a significant decrease in capillary perfusion in mu scle flaps over 24 hours although the blood flow through the thrombogenic m ain feeding vessel is maintained.