Previously, we found that intermittent flushing of indwelling arterial catheters frequently resulted in arterial occlusion and catheter dysfunction. Twenty-gauge Teflon catheters, which caused less thromboses than 18-gauge catheters, still caused thrombus formation that nearly occluded the vessel within four days. To study the effect of constant irrigation and to evaluate the difference between 20-gauge Teflon and 20-gauge heparin sodium-impregnated polyethylene catheters, 20 patients were observed. Their radial arteries were cannulated and the catheters were connected to a constant infusion system. Arteriograms disclosed that heparin-impregnated polyethylene catheters resulted in significantly more thrombus formation than Teflon catheters. Teflon catheters maintained with a constant irrigation system resulted in minimal thrombus formation even when the catheter had been in place for up to ten days.
Downs MJB, Chapman RL, Hawkins IF. Prolonged Radial-Artery CatheterizationAn Evaluation of Heparinized Catheters and Continuous Irrigation. Arch Surg. 1974;108(5):671-673. doi:10.1001/archsurg.1974.01350290035004