RESUMO
Avoidance of vein endothelial injury is the sine qua non of successful bypass grafting. Both early and late thrombotic events may have their origin in the surgeon's failure to preserve the structure and function of the endothelium, especially in veins less than 4mm diameter. During vein preparation, the pressure of distension, temperature and choice of solution are all important in minimising endothelial damage. Because perfluorochemicals have been successfully used as a blood substitute, we investigated their value in vein graft preparation. Forty-eight canine veins were distended and stored in either oxygenated blood, normal saline or a perfluorochemical, Fluosol DA 20 percent (FDA). Veins were distended at either 250 or 500 mm Hg for 15 minutes and stored at 4§C or 37§C for 45 minutes. Oxygen was bubbled through all solutions. Samples were fixed and examined by scanning and transmission electron microscopy. Distension in warm saline at 500 mm Hg produced the most endothelial damage while at 250 or 500 mm pressure, cold saline and warm and cold blood resulted in lesser degrees of injury. The least damage was produced by distension at 250 mm Hg and storage, using cold FDA. In the preparation of canine veins, FDA preserves endothelial structure better than either blood or saline (AU)