Effect of inflow cannula side-hole number on drainage flow characteristics: flow dynamic analysis using numerical...

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Fluid Dynamics

Background:

• Optimizing venous drainage is critical for safe cardiac surgery.
• The ideal venous drainage cannula design remains undetermined.
• This study investigates the impact of side-hole configurations on cannula performance.

Purpose of the Study:

• To evaluate the effect of increasing side-hole numbers on venous drainage cannula performance.
• To determine the optimal cannula design for efficient venous drainage.
• To elucidate the relationship between side-hole configuration and flow dynamics.

Main Methods:

• Computational simulation of venous drainage was performed.
• Six cannula models were evaluated: end-hole (EH) and 4, 6, 8, 10, 12 side-hole (SH) configurations.
• Total side-hole area was fixed at 120 mm²; end-hole area was 36.3 mm².

Main Results:

• Mean venous drainage flow rates were: EH (2.57 L/min), 4SH (2.52 L/min), 6SH (2.51 L/min), 8SH (2.50 L/min), 10SH (2.49 L/min), 12SH (2.41 L/min).
• Flow rate decreased as the number of side-holes increased.
• The end-hole (EH) model demonstrated the highest flow rate.

Conclusions:

• Increasing side-hole numbers leads to flow separation and energy loss, reducing overall drainage efficiency.
• The end-hole cannula design provides the best flow rate and profile.
• Flow separation at side-holes hampers the main flow, making the EH cannula superior.