Influences and Actual Flow Rates for Vascular Access Catheters Using Simulated Blood Vessels and Blood

Abstract

The outer diameters for vascular access catheters can range between 11-13 Fr. These sizes are relatively large when inserted into, for example, the jugular vein and may hinder the venous bloodstream in various degrees. In addition, because the lumen within the catheter is quite narrow, the actual blood removal rate may be lower than that indicated on the pump, possibly affecting treatment adversely. In this study, various catheters of different sizes were inserted into simulated veins. The blood flow rates within the simulated veins before and after catheter insertion were measured. In addition, the lumen blood removal flow rates were measured and compared with the indicated rates, along with any drop in blood pressure. The results showed a drop in the venous flow rate of as much as 15%, with an average drop of about 10%. The actual blood removal flow rates from the simulated veins were lower than that indicated on the pumps, and the difference in these two rates became increasingly larger as the indicated flow rates were increased. Any drop in blood pressure was linked to the tip and cross-sectional shapes of the catheters. In conclusion, this study clearly shows that there is a discrepancy between the actual blood removal rate and the indicated rate when using catheters for removing and treating blood, and that the catheters inserted into the simulated veins influence the actual flow rate.