Enhancement of fluorescein perfusion in experimental skin flaps following postischemic washout with iloprost, urokinase, verapamil, and University of Wisconsin solution

The enhancement of blood flow in experimental skin flaps following postischemic perfusion washout was investigated in rats. Unilateral island skin flaps based on the superficial epigastric vessels were raised and subjected to 6 hr of primary ischemia. Group 1 was designated as a control and did not undergo postischemic perfusion washout. In the remaining rats, postischemic washout was performed with one of five agents: Group 2-lactated Ringer's solution; Group 3-University of Wisconsin solution, an organ preservation medium; Group 4-verapamil, a calcium channel blocker; Group 5- urokinase, a thrombolytic agent; Group 6-iloprost, a stable prostacyclin analog. Two hours following perfusion washout, fluorometric analysis revealed a statistically significant enhancement of blood flow in Groups 4, 5, and 6, compared to Groups 2 and 3 (p <0.05). Furthermore, a significant increase in skin surface fluorescence was demonstrated in all the flaps that underwent perfusion washout, compared to the control flaps (p <0.05). By analyzing skin surface fluorescence, the enhancement of nutritive blood flow in flaps, following postischemic perfusion washout, was evaluated. This is the first study in which the above pharmacologic agents were compared in a quantitative manner.