COOL PERFUSION SOLUTIONS FOR SKIN FLAPS - A NEW MIXTURE OF PHARMACOLOGICAL AGENTS WHICH IMPROVES SKIN FLAP VIABILITY

This study tested the hypotheses that perfusion of cooled skin flaps w ith established organ preservation solutions improves their viability and that this improvement can be further enhanced by pharmacological m anipulation. Rabbit epigastric skin flaps were perfused with different solutions before explantation and stored at 8 degrees C for 6 days. I n the first part of the experiment, flap viability was assessed 7 days after reperfusion of the flap via microvascular anastomoses. The diff erent solutions were heparinised blood, University of Wisconsin soluti on, two of its modifications, EuroCollins solution and a pharmacologic al mixture containing phosphoenolpyruvate, desferrioxamine, nitrendipi ne, dextran 70 and a platelet-aggregating factor receptor antagonist ( WEB 2170). In the second part, biochemical parameters of skin were mea sured at various reperfusion times. Adenosine triphosphate (ATP), redu ced glutathione (GSH), myeloperoxidase (MPO) and tissue water were ass ayed at 0, 1, and 24 h after reperfusion. In addition, plasma thrombox ane (TXB(2)) was measured at 0, 30 and 60 minutes after reperfusion. T he viability of flaps perfused with the mixture (81%) was significantl y higher than that of any of the other groups (39% for controls, 38% f or EuroCollins, 13% for UW solution, 27% and 31% for its modifications ). ATP levels after reperfusion were higher in the mixture group than in UW-perfused group. GSH levels in the mixture group were also higher than in the UW group, indicating higher level of protection against o xidative stress during reperfusion. There were no differences in MPO l evels. Thromboxane levels associated with UW-perfused flaps were signi ficantly higher than those associated with any other perfusion solutio n. In conclusion, perfusion of a mixture of pharmacological agents tar geting specific aspects of ischaemia/reperfusion injury improved the v iability of skin flaps stored in the cold for 6 days, whereas standard organ preservation solutions failed to affect significantly skin flap survival.