IMMUNOLOGY OF THE EXTRACORPOREAL CIRCUIT COMPONENTS

Blood essentially exhibits a complex, immunologic response to all ECC components. The issues in regard to ECC activation are the (1) blood-gas interface, (2) the blood volume to surface area ratio and duration of exposure, (3) the type of material and the physical properties that the surface exhibits and (4) device design turbulence or high shear stress. Attenuation of the immunological response to ECC components may be achieved by (1) reducing component surface area, blood-gas interface and duration of exposure, (2) precoating the ECC surface with wetting agents, proteins, or covalently bonded heparin, (3) removal of chemical mediators by adsorption or filtration and (4) pharmacologically blocking blood's normal response to foreign surfaces (Riegel et al., 1988; Markewitz et al., 1993). This review serves only as an introduction to the intricate problems and far-reaching work by many investigators toward the challenge of reducing ECC activation of the blood's inflammatory response. © 1993 Pergamon Press Ltd.