SCANNING ELECTRON-MICROSCOPIC INVESTIGATION OF CATHETERS FOR BLOOD ACCESS

Using blood-contacting catheters, infections, thromboses, and stenoses are among the most frequent complications. They are caused by surface properties of the basic material. Ion beam based processes such as io n implantation (silicone rubber) and ion beam assisted deposition (sil ver-based coatings) affect only the outer micron of the treated materi al surface; there is little effect on bulk properties. These processes were employed also in the production of large-bore catheters used for extracorporeal detoxification. In a prospective study in 56 patients, 72 large-bore catheters were inserted into the internal jugular and s ubclavian veins and investigated after removal for bacterial colonizat ion using a scanning electron microscope. In 24 patients 30 surface-tr eated catheters (Spi-Argent I n = 14; Spi-Silicone n = 16) were used. 42 untreated catheters used in 32 patients served as controls. Bacteri al colonization was observed in 8.9% in contrast to 38.1% in untreated catheters. The scanning electron microscopic investigations showed in all catheters a low thrombogenicity. The ion beam based processes mak e the surface-treated catheters thrombus and infection resistant.