Dynamic oxygenator blood volume during prolonged extracorporeal life support

Area of Science:

• Cardiovascular Sciences
• Biomedical Engineering
• Critical Care Medicine

Background:

• Current methods for detecting oxygenator clotting during extracorporeal life support (ECLS) lack quantitative assessment.
• Visual inspection and indirect measures do not precisely track clot formation.
• There is a need for a reliable method to quantitatively assess oxygenator health during prolonged ECLS.

Purpose of the Study:

• To evaluate the relationship between dynamic oxygenator blood volume and oxygenator resistance and oxygen transfer performance.
• To establish a quantitative measure for oxygenator clot formation during ECLS.
• To determine if changes in blood volume can predict oxygenator dysfunction.

Main Methods:

• Sixty-seven oxygenators were monitored during adult ECLS.
• Key parameters measured included dynamic oxygenator blood volume, oxygenator resistance, and oxygen transfer efficiency.
• Statistical analysis was performed to assess correlations between these parameters and runtime.

Main Results:

• Oxygenator blood volume showed a statistically significant decrease with increasing runtime (r = -0.462; p < 0.001).
• A significant negative correlation was found between oxygenator blood volume and resistance (r = -0.476; p < 0.001), particularly in exchanged oxygenators and those with lower blood volumes.
• No significant correlation was observed between oxygenator blood volume and oxygen transfer efficiency.

Conclusions:

• Dynamic oxygenator blood volume declines over time during prolonged ECLS.
• This decline is associated with increased oxygenator resistance, suggesting it is a sensitive indicator of clot formation.
• Oxygenator blood volume changes appear to be a more direct indicator of clotting than oxygen transfer performance.