Analysis of blood trauma
Blood exposed biomedical devices (e. g. blood pumps, mechanical heart valve prostheses, oxygenators) provoke blood trauma. Mechanical, flow induced damage of blood cells and blood contact with artificial surfaces (biocompatibility and bio material) are considered to be the dominant causes of blood trauma. Erythrocytes are damaged (haemolysis) and the coagulation is activated (thrombus fotmations).
- CAD of Couette cell
Method
To analyse the relevant influencing factors under specific flow conditions, a Couette system has been developed at the Helmholtz Institute \1, 2\. In the Couette system blood passes a micro shear gap. The adjustable loads and exposure times of the Couette system cover the stress range in blood pumps. In experiments parameters as e. g. haemolysis index, cell number, activated coagulation etc. are determined. Changes in parameter sets give information about the impact of stress on the blood.
On the basis of this data a mathmatical model for bood damage is being established. Thus, the results can be transferred to the more complex flow patterns in blood pumps and heart valve prostheses.
