Experimental study on blood flow rate measurement using intravascular catheter

Measurement of blood flow rate is essential in assessing the cardiovascular status of patients with coronary artery diseases during treatments. It provides feedback and monitors any improvements in the vascular system after the cardiovascular surgery. This paper presents the latest development of a new approach to measure blood flow rate using a catheter involving the concept of heat exchanger. In the study, an intravascular catheter is inserted into a simulated blood stream and a heat transfer element attached at the distal end extracts a small amount of heat from blood to the cooling fluid in the heat transfer element. We can correlate the blood flow rate to the change of the outlet temperature of the cooling fluid. In this approach, we can determine the cardiac output without the need for introduction of saline solution or other substance into patient body. Unlike Swan-Ganz catheter, it does not alter the blood temperature. Consequently, it is repeatable without any possible adverse effects due to altering blood composition or heating in the vascular system. In this experimental study, we have done the comparison between different designs and settings, and confirmed that this approach has a great potential to be an effective way of measuring blood flow rate as, well as cardiac output.