Flow patterns through side holes of venous cannula in mock circulation loop

Area of Science:

• Cardiovascular Engineering
• Biomedical Fluid Dynamics

Background:

• Cannulae with multi-staged side holes (SHs) are crucial for venous drainage in extracorporeal circulation.
• Current understanding of catheter flow performance is often based on intuition rather than empirical data.

Purpose of the Study:

• To develop and utilize a mock circulation loop for objective evaluation of venous drainage cannula performance.
• To analyze the fluid dynamics of multi-staged side hole cannulae under varying flow conditions.

Main Methods:

• Development of a mock circulation loop simulating physiological conditions.
• Systematic evaluation of cannula flow performance across a range of pump flow rates (250-750 mL/min and ≥750 mL/min).
• Analysis of flow rate changes through individual side holes and percentage inflow distribution.

Main Results:

• No significant differences in the rate of change of flow through SHs were observed between 250-750 mL/min.
• At pump flow rates ≥750 mL/min, increased flow rate changes were noted towards proximal SHs.
• Percentage inflow shifted towards proximal SHs and decreased in distal SHs at higher flow rates.

Conclusions:

• The mock circulation loop provides a reliable method for cannula performance evaluation.
• Understanding flow dynamics at different pump rates aids in optimizing venous drainage.
• Findings can inform the design of novel cannulae for improved extracorporeal circulation procedures.