SURFACE MODIFICATION OF INTRAVENOUS CATHETERS TO REDUCE LOCAL TISSUE-REACTIONS

Surface modification of polymer materials used in intravascular cathet ers reduces the in vitro adhesion of plasma proteins involved in blood coagulation. Intravenous Teflon(R) cannulae, native and surface-modif ied with ethyl hydroxyethyl cellulose, were compared using clinical ex amination and laser Doppler flowmeter (LDF) measurements of local cuta neous blood flow. Nine volunteers were simultaneously subjected to bot h types of cannulae for a period with a maximum of 4 d. Native Teflon catheters showed a larger incidence of catheter-associated tissue reac tions, first demonstrated by early increases in laser Doppler recordin gs of skin blood flow. These results indicate that surface modificatio n of polymer intravascular catheters attenuates tissue response agains t the foreign material and that altered LDF measurement precedes the c linical recognition of thrombophlebitis.