Low-flow assessment of current ECMO/ECCO2R rotary blood pumps and the potential effect on hemocompatibility
Sascha Gross-Hardt,
Felix Hesselmann,
Jutta Arens,
Ulrich Steinseifer,
Leen Vercaemst,
Wolfram Windisch,
Daniel Brodie,
Christian Karagiannidis
Affiliations
Sascha Gross-Hardt
Department of Cardiovascular Engineering, Medical Faculty, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University
Felix Hesselmann
Department of Cardiovascular Engineering, Medical Faculty, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University
Jutta Arens
Department of Cardiovascular Engineering, Medical Faculty, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University
Ulrich Steinseifer
Department of Cardiovascular Engineering, Medical Faculty, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University
Leen Vercaemst
Department of Perfusion, University Hospital Gasthuisberg
Wolfram Windisch
Department of Pneumology and Critical Care Medicine, Cologne-Merheim Hospital, ARDS and ECMO Center, Kliniken der Stadt Köln gGmbH, Witten/Herdecke University Hospital
Daniel Brodie
Center for Acute Respiratory Failure, Columbia University College of Physicians and Surgeons/New York-Presbyterian Hospital
Christian Karagiannidis
Department of Pneumology and Critical Care Medicine, Cologne-Merheim Hospital, ARDS and ECMO Center, Kliniken der Stadt Köln gGmbH, Witten/Herdecke University Hospital
Abstract Background Extracorporeal carbon dioxide removal (ECCO2R) uses an extracorporeal circuit to directly remove carbon dioxide from the blood either in lieu of mechanical ventilation or in combination with it. While the potential benefits of the technology are leading to increasing use, there are very real risks associated with it. Several studies demonstrated major bleeding and clotting complications, often associated with hemolysis and poorer outcomes in patients receiving ECCO2R. A better understanding of the risks originating specifically from the rotary blood pump component of the circuit is urgently needed. Methods High-resolution computational fluid dynamics was used to calculate the hemodynamics and hemocompatibility of three current rotary blood pumps for various pump flow rates. Results The hydraulic efficiency dramatically decreases to 5–10% if operating at blood flow rates below 1 L/min, the pump internal flow recirculation rate increases 6–12-fold in these flow ranges, and adverse effects are increased due to multiple exposures to high shear stress. The deleterious consequences include a steep increase in hemolysis and destruction of platelets. Conclusions The role of blood pumps in contributing to adverse effects at the lower blood flow rates used during ECCO2R is shown here to be significant. Current rotary blood pumps should be used with caution if operated at blood flow rates below 2 L/min, because of significant and high recirculation, shear stress, and hemolysis. There is a clear and urgent need to design dedicated blood pumps which are optimized for blood flow rates in the range of 0.5–1.5 L/min.
