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A comparative study of several polymers for use as intravenous catheters.

The widespread use of long-term intravenous catheters has produced some concern on the part of the clinician with respect to morbidity and occasional mortality associated with their use. Fourteen polymer surfaces were evaluated in experimental animals in this study. Several of the materials are commercially available; the others are experimental. In all, 160 catheters were placed in the femoral and jugular veins through side branches. The catheters were evaluated in terms of thrombosis, phlebitis, and periphlebitis, using an arbitary grading system. Scanning electron microscopy and light microscopy were employed to document the results. The most successful catheter materials were next evaluated in man, using the same experimental parameters. It is our belief that the observed thrombosis associated with morbidity is largely due to the surface characteristics of the catheter materials. These characteristics are largely surface phenomena related to the interactions between the tissue and catheter material. In this study, we have attempted to determine whether there are any significant differences in thrombogenicity and/or long-term function between the several currently available catheters. Based on this study, ethylene acrylic acid appears to be the most nonthrombogenic surface of the material tested.