ABSTRACT
We inserted the 0.6 mm caliber graft-heparin (in inner wall) conduits into the tailarteries of 14 mice. The results showed that the graft conduit could be used repeatedly with no blood oozing out in the wound, no massive internal hemorrhage, and no additional coagulative reagent given during the whole experiment. On the other hand, the graft-heparin conduits of variant caliber were inserted into the femur arteries of 4 rabbits and 4 dogs for blood pressure experiment and femur arterio-venous bypass tests. The results showed that the anticoagulative effect of these conduits was markedly improved, but there was a strip of thrombus. There was no thrombus track in the wall of the conduit. The strip of thrombus was formed first in the cone of conduit where caliber changed. The results indicate that the blood flow resistance is in inverse proportion to 4 power of the conduit radius. So the thinner the conduit is, the more sensitive to conduit radius variation the conduit resistance will be. In studying and making the arfificial conduit, one must take notice of the conduit caliber, which should be equal to the caliber of the blood vessel.