Risk analysis and detection of thrombosis by measurement of electrical resistivity of blood

Abstract

Monitoring of thrombogenic process is very important in ventricular assistance devices (VADs) used as temporary or permanent measures in patients with advanced heart failure. Currently, there is a lack of a system which can perform a real-time monitoring of thrombogenic activity. Electrical signals vary according to the change in concentration of coagulation factors as well as the distribution of blood cells, and thus have potential to detect the thrombogenic process in an early stage. In the present work, we have made an assessment of an instrumentation system exploiting the electrical properties of blood. The experiments were conducted using bovine blood. Electrical resistance tomography with eight-electrode sensor was used to monitor the spatio-temporal change in electrical resistivity of blood in thrombogenic and non-thrombogenic condition. Under non-thrombogenic condition, the resistivity was uniform across the cross-section and average resistivity monotonically decreased with time before remaining almost flat. In contrary, under thrombogenic condition, there was non-uniform distribution across the cross-section, and average resistivity fluctuated with time.

W053006 The Electrical Impedance Measurement of Thrombus

“…The experiments were conducted with the setups sho hl figure 1． There are tWo different setUps ． The first one ( figure La ) was used to visualize the spatio − temporal change in the cross −sectional resis 樋vity by tomogmphic measurement when extemally prepared thrombus is dropped． In this case ， 45 ml of blood was put in to the container． Extcmally prepared thrombi ofvarious sizes were dropped separately to visualize the change ． The detail tomography measurement procedures are described in one ofour paper ( 1) ． The purpose of another setup ( figure 1． b ) was to visualize 重 he thrombogenic process from the very begi ing ( 廴e． even before the elnboli are forr 皿 ed ) ． The experiments were carried out for thrombogenic and non − thrombogenic blood separately ． Detailed experimental procedures ， and conditions th飢 are defined as thrombogenic and…”