An experimental study on the effect of prostaglandin e1 on the random pattern flap survival in the rats

ABSTRACT

The survival of skin flap has vital importance in plastic surgery. Many clinical and experimental researches have been carried out to increase the survival of skin flap. As a result of these researches, many drugs have been used clinically and experimentally for increasing the survival of skin flap, and prostaglandin E1 is known to be used for improving peripheral circulatory disturbance. The pharmacophysiologic mechanisms of the effect of prostaglandin E1 are 1) increasing blood flow by dilatation of smooth muscle of small sized vessels, 2) inhibition of aggregation of platelets, 3) increasing arteriolar blood flow by improving fluidity of erythrocytes, 4) preclusion of free-radical formation, 5) decreasing the endothelial cell damage by down- regulation of sensitivity for eosinophils, 6) making the endothelial cell be refractory to adrenergic stimulation, and 7) promotion of secretion of erythropoietin in the kidney. In this terms, in order to validate effectiveness of preoperative administration of prostaglandin E1 as a pharmacological flap delay, following experimental study was performed. Forty male Sprague-Dawley rats were divided into 4 groups and caudally based 2x8 cmsized flap was elevated on dorsal surface. In group 1, normal saline (0.25 ml/kg) was injected intraperitoneally as control, in group 2, 1 microgram/kg of prostaglandin E1 was injected intraperitoneally for preoperative seven days, in group 3, 1 microgram/kg of prostaglandin E1 was injected intraperitoneally for seven preoperative days, and in group 4, 1 microgram/kg of prostaglandin E1 was injected intraperitoneally for seven days preoperatively and for seven postoperative days. On the seventh postoperative day, the animals were sacrificed and the flap survival area was measured. The following results were obtained. 1. On the seventh postoperative day, the flap survival rates of group 2, 3, 4 were higher than that of group 1 with a statistical significance. 2. On the seventh postoperative day, the flap survival rate of group 3 was higher than group 2, but there was no statistical significance. 3. On the seventh postoperative day, the flap survival rate of group 4 was higher than that of group 2 and 3 with a statistical significance.In conclusion, preoperative administrations of prostaglandin E1 increase flap survival equally as when it is administrated postoperatively, and the improvement in flap survival can be enhanced by continuous administration of prostaglandin E1 in preoperative and postoperative period. So it is expected that surgical flap delay procedure is replaced by pharmacological flap delay by the use of prostaglandin E1 preoperatively.