I IO 



Scientific Proceedings (29). 



animal and perform a double anastomosis. The success of the 

 operation is due to the fine technique elaborated by Carrel. 



Now, the question arises, upon what does this success depend ? 

 This question has not only a technical, operative, but a general 

 physiological interest. To implant an arterial segment success- 

 fully means to avoid an intravascular thrombus after the operation. 



According to the generally accepted theory of Brucke, blood 

 remains fluid as long as it circulates in a vessel lined with an un- 

 impaired living endothelium. Should the endothelium be injured 

 through infection or trauma, a thrombus must form. In Carrel's 

 experiments with implantation of arterial segments of the same 

 species of animals, it seemed probable that the implanted segments 

 remained alive. But in implantation of arterial segments of differ- 

 ent animal species, the question presented itself whether these 

 segments really remain alive, or, whether it is possible to implant 

 devitalized arterial segments and the theories of intravascular coagu- 

 lation of blood have to be revised. Our experiments consisted in 

 implantations of a segment of an aorta from a dog, about one inch 

 long, hardened in 4 per cent, formalin, into the abdominal aorta of 

 another dog. 



On January 23, 1908, we performed the first experiment. For 

 ten days the dog did well ; there was normal pulsation in both 

 femoral arteries. On the eleventh day, the animal was found in 

 the morning with protruding intestines. A secondary laparotomy 

 was performed, but the dog died during the day. Both anasto- 

 moses held perfectly ; the implanted piece was patent, without any 

 thrombi. Microscopically there was hardly any cellular structure 

 to be found in the implanted piece, but the elastic fibers could be 

 seen in nearly normal quantity. 



We then did some unsuccessful experiments on implantation 

 of boiled arteries and ureters (from a freshly autopsied human 

 body) hardened in formalin, in a dog and cat. 



Meanwhile, Guthrie reported successful implantation of formal- 

 ized segments into the carotid of a dog. We repeated the experi- 

 ments and must state that in places where we felt pulsation during 

 life the implanted segment contained an organized thrombus with 

 numerous blood vessels running through it. 



On May 8, last, we performed another experiment with implan- 



