Veno-right ventricular cannulation reduces recirculation in extracorporeal membrane oxygenation

Area of Science:

• Cardiovascular physiology
• Extracorporeal life support
• Respiratory failure management

Background:

• Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is used for severe respiratory failure.
• Recirculation, where oxygenated blood returns to the pump instead of the body, limits VV-ECMO efficacy.
• Returning blood to the right ventricle may reduce recirculation.

Purpose of the Study:

• To compare recirculation between veno-right ventricular support (VRV) and conventional VV-ECMO.
• To assess the relationship between pump flow and recirculation in both support modalities.

Main Methods:

• Five greyhound dogs underwent percutaneous cannulation for both VRV and VV-ECMO.
• Recirculation was measured by comparing oxygen levels in circuit lines.
• Measurements were taken at pump flows from 0.5 to 4 L/min.

Main Results:

• VRV significantly reduced recirculation at 4 L/min pump flow (8.4% vs. 37.9%, p=0.0076).
• Recirculation increased less with pump flow in VRV (2.9%/L/min vs. 11.1%/L/min, p<0.0001).

Conclusions:

• Returning blood to the right ventricle dramatically reduces recirculation in ECMO.
• This approach enhances oxygen delivery to the lungs and systemic circulation.
• Specialized catheters could further improve VRV safety and efficacy.