Bioelectric Phenomena, Thrombosis and Plastics: A Review of Current Knowledge
THE rapid development of new plastic polymers and their immediate, sometimes regretfully early, application in cardiovascular surgery have brought up once more the problem of compatibility between blood and foreign surfaces. The manufacturers of plastics with their technologic facilities have almost succeeded in producing materials that would satisfy the classic standards of strength, elasticity, chemical inertness, biologic acceptability, water repellency, and smoothness. Experimental testing on animals and clinical application of these materials have given some fair and many disappointing results. If a truly imaginative application of plastics in cardiovascular surgery is to come, then a thorough study of the basic characteristics of blood vessels, blood, and hemodynamics should give us some understanding about the process that occurs when blood comes in contact with a plastic. This paper represents an effort to review and to coordinate some well-known data from the literature.
Thrombosis and Morphologic Changes of the Intima
For many years the smoothness and nonwettability of intima were considered to be responsible for the minimal friction of the circulating blood and, consequently, to be the defense against intravascular clotting. Later investigations of Samuels and Webster,1 have produced evidence of an active reaction of the intima to physical and chemical damage, and the close relationship of this reaction to the thrombotic process. It has been found that at the beginning of the injury or when injury is not great, the cells of the intima do not change morphologically, but that fibrin and platelets temporarily adhere firstly to the intercellular lines and . . .