Blood flow induced thrombosis and stenosis due to cannulation – an interdisciplinary study

Introduction

In extracorporeal organ support (ECOS), one or more organ functions fail and are replaced by an artificial device. Kidney failure requires hemodialysis, at least until transplantation. Temporary lung- and/or heart-failure may be treated by Extracorporeal Membrane Oxygenation (ECMO).

Global Impact

About 1.5 million patients require hemodialysis worldwide. ECMO has an essential life-saving role during the ongoing COVID-19 pandemic, as well as during the Influenza H1N1 pandemic in 2009.

Mechanism of ECOS

In ECOS, two or more accesses are used:

• One for blood drainage
• Another to return oxygenated blood.

The flow rate in the cannula and the cannulated blood vessels is often significantly higher than physiologically experienced. The high flow velocity implies larger forces (stress) acting on the blood cells and the vessel walls.

Complications

Thromboembolism and morphological and mechanical changes in the affected blood vessel are common complications in ECOS. This project focuses on the impact of blood flow on these complications.

Methodology

Patient-specific data (CT, MRI, and Ultrasound based) will be used to construct laboratory and simulation relevant frameworks. Set-ups for measurement of flow and mixing in-vitro will be used.

Simulations will include:

1. Modeling of transport of chemical species and blood cells
2. Modeling of platelet activation and risk for thrombus formation

The different tools will enable a considerably better understanding of the underlying pathological processes.

Expected Outcomes

The results will support further model development of these processes and facilitate improved cannulation techniques and new devices. These propositions are to be assessed by our clinical partners.

Project Team

Therefore, the project group includes fluid mechanical expertise, as well as clinical specialists in nephrology, intensive care/ECMO, and radiology.

Conclusion

The outcome of the research will enable device development and clinical decision-making, reducing overall treatment complications.