678 CARREL— FURTHER STUDIES ON [November 6, 



Before describing the method which renders possible the preser- 

 vation of arteries, I shall briefly summarize some of the results 

 obtained at the Rockefeller Institute in the transplantation of blood 

 vessels and organs. These operations became possible as soon as a 

 practical method of uniting blood vessels was found. Success in 

 transplanting organs is direct function of the circulation. The cir- 

 culation cannot be immediatel}^ reestablished but by the sewing of 

 the vessels of the organ to those of the host. The sewing of vessels 

 is today a very easy operation. Some years ago, while I was work- 

 ing at the University of Lyons, I found a method of uniting severed 

 arteries or veins, which gave excellent results. This method was 

 progressively improved in such a manner that it is practically 

 always successful. The vessels heal very quickly and no coagula- 

 tion of the blood occurs when the operation is aseptic and the union 

 of the vascular ends accurate. The scar of the severed vessels is, 

 in many cases, so small that after a few months it is hardly dis- 

 cernible. On a renal vein examined a little over two months after 

 the sewing, it was impossible to localize exactly the position of the 

 anastomosis. The anastomosis of the renal artery was represented 

 only by an indistinct line crossing the intima. Twelve months after 

 the anastomosis of a carotid artery, the anatomical specimen was re- 

 moved and examined. After longitudinal incision of the wall, no 

 scar was seen on the intima, there was no modification of the caliber. 

 But, in one small point, the vessel had lost part of its elasticity and 

 it permitted to localize approximately the anastomosis. The results 

 are permanent. Two and three years after the operation, the circu- 

 lation through the anastomosis remains normal. It must be known 

 also that, if the method is not correctly applied, or a fault of tech- 

 nique, even very slight, is made, thrombosis may occur. Success 

 depends much less on the way of handling the needles or passing 

 the threads than on the knowledge of the causes which are able to 

 produce thrombosis and their removal. On human beings, this 

 method has already been successfully used by American and Euro- 

 pean surgeons, and on animals, it has permitted to perform the 

 transplantation of blood vessels, organs and limbs. 



The graft of a segment of artery on an artery of another animal 

 of the same species is ordinarily successful when the vessels are of 



