Recirculation rate of non-cuff type catheter in different vessel diameters

Abstract

Using a non-cuff type catheter (catheter) enables recirculation in patients with an unusually thin vessel diameter caused by bleeding defects and changes in blood flow dynamics. During treatment, the catheter is usually connected in forward connection-, using the inflow lumen for blood inflow. However, if inflow failure occurs in the catheter, there is a possibility for reversal connection, where the outflow lumen is used for blood inflow. Recirculation is more likely to occur in reversal connection. In this study, we measured whether the difference in vessel diameter affects the recirculation rate, using three types of catheters. We used catheter’s tip shapes were end-hole types (inflow hole is on the same side or the other side), and streamlined catheters. In end-hole type catheters, recirculation did not occur during forward connection but occurred during reversal connection. Furthermore, recirculation rate increased as the simulated blood vessel diameter decreased. In the streamlined-type catheter, mild recirculation occurred during both forward and reversal connections. However, recirculation rate was nearly constant for all catheters, regardless of the simulated vessel diameter. Accordingly, there is a possibility that recirculation rate will become higher by catheter tip shape and connection method, in patients with thin vessel diameter.