Event Title
Effect of Negative Angle Cannulation during Cardiopulmonary Bypass – A Computational Fluid Dynamics Study
Location
Hager-Lubbers Exhibition Hall
Description
PURPOSE: Cardiopulmonary bypass (CPB) is a procedure used to deliver oxygenated blood to a patient’s tissues while the cardiovascular system is not functional. The procedure itself varies significantly on a case to case basis. Negative angle cannulation directs blood leaving the cannula toward the clamped aortic root. This study proposes that using a negative angle for cannulation will allow the blood flow to develop in a manner that balances flow distribution, lessens both wall shear stresses and normal stresses on the aorta, and ensures little stagnant flow to avoid thrombotic embolism. METHODS AND MATERIALS: SolidWorks 2016 was used to create, modify, and export the aorta geometry. The Star CCM+ V11.04 was used to pre-process, mesh, solve, and post-process all simulation results. The fluid domain solved repetitively using 0° to -60° angles. ANALYSES: The resulting simulations were analyzed for flow distributions, wall shear stress and normal stress on the aorta walls, isosurfaces to show areas of hemolysis, and produced streamline flow structures. RESULTS: It was found that the -45° case yielded a maximum of 4% discrepancy with normal cardiac operation. The -60° case had the best reduction in wall shear stress and normal shear stress values compared to literature; at 84%. There was little to no areas of hemolysis in the aorta. -30°, -45°, and -60° all produced helical flow in the aortic arch, matching expected cardiac flow. CONCLUSIONS: In cases with low risk of stroke due to atherosclerotic embolism generation in the root, negative angle cannulation could be useful.
Effect of Negative Angle Cannulation during Cardiopulmonary Bypass – A Computational Fluid Dynamics Study
Hager-Lubbers Exhibition Hall
PURPOSE: Cardiopulmonary bypass (CPB) is a procedure used to deliver oxygenated blood to a patient’s tissues while the cardiovascular system is not functional. The procedure itself varies significantly on a case to case basis. Negative angle cannulation directs blood leaving the cannula toward the clamped aortic root. This study proposes that using a negative angle for cannulation will allow the blood flow to develop in a manner that balances flow distribution, lessens both wall shear stresses and normal stresses on the aorta, and ensures little stagnant flow to avoid thrombotic embolism. METHODS AND MATERIALS: SolidWorks 2016 was used to create, modify, and export the aorta geometry. The Star CCM+ V11.04 was used to pre-process, mesh, solve, and post-process all simulation results. The fluid domain solved repetitively using 0° to -60° angles. ANALYSES: The resulting simulations were analyzed for flow distributions, wall shear stress and normal stress on the aorta walls, isosurfaces to show areas of hemolysis, and produced streamline flow structures. RESULTS: It was found that the -45° case yielded a maximum of 4% discrepancy with normal cardiac operation. The -60° case had the best reduction in wall shear stress and normal shear stress values compared to literature; at 84%. There was little to no areas of hemolysis in the aorta. -30°, -45°, and -60° all produced helical flow in the aortic arch, matching expected cardiac flow. CONCLUSIONS: In cases with low risk of stroke due to atherosclerotic embolism generation in the root, negative angle cannulation could be useful.