HemoSim - Flow-induced hemolysis in blood-carrying medical devices – a data-based mechanistic approach

  Process of extraction and modeling of shear stress histories Copyright: © CVE Process of extraction and modeling of shear stress histories

Background:

Blood-carrying medical devices have provided life-saving solutions for patients with severe cardiovascular and respiratory diseases which are the first and third most frequent causes of mortality worldwide with a total of 21.7 million deaths in 2017. Despite the tremendous improvements in patient survival and overall quality of life over the last decades, device induced blood traumatization and damage is still a major source for complications. The damage of the red blood cell membrane and the subsequent release of hemoglobin is called hemolysis and is one of the decisive complications associated with increased mortality. Hemolysis leads to a reduced oxygen supply of organs and plays a central role in other blood related phenomena such as platelet activation and thrombus formation.

Methods:

A better understanding of mechanically induced hemolysis using experimental and numerical methods is necessary to improve the design of current blood-carrying medical devices. On this front, computational fluid dynamics (CFD), has become a widely used tool to capture the complex phenomena of blood flow dynamics and the device induced hemolysis. However, current numerical modeling approaches lack quantitative prediction potential due to shortcomings in the experimental data basis and a scarcity of reproducible methods.

The overarching goal of the proposal is to improve the prediction potential of numerical hemolysis models. At first, blood damage at various shear rates and exposure times will be measured and the data will undergo various data analysis and quality control techniques to ensure a reusable dataset. In the next step, a benchmarking setup with all existing hemolysis models will be created and the measured dataset will be included. Lastly, new experimental methods to model the transient damage history of red blood cells in rotary blood pumps will be developed and existing numerical models of hemolysis will be expanded to better describe the occurring blood damage mechanisms.

Ultimately the benchmarks and the blood damage dataset will be presented via an online platform to allow reusability by other research groups beyond the scope of the project.

Expected results:

The proposed project puts a major focus on standardization, reproducibility and data integration in order to tackle the intrinsic complexity of hemolysis and the diversity of existing numerical models. It focuses on a central problem in blood-carrying medical devices and offers many clinical applications such as mechanical heart support systems or extracorporeal lung support (ECMO).