Seventy-two Hour Gas Exchange Performance and Hemodynamic Properties of NOVALUNG ILA As a Gas Exchanger for Arteriovenous Carbon Dioxide Removal

Objective: Acute respiratory failure is complicated by acidosis and altered end-organ perfusion. NOVA-LUNG iLA is an interventional lung assist (ILA) device for arteriovenous carbon dioxide removal (AVCO2R). The present study was conducted to evaluate the device for short-term CO2 removal performance and hemodynamic response.

Methods: Six adult sheep received cannulation of the jugular vein and carotid artery. The ILA-AVCO2R circuit was placed on the sheep for 72 hours. Hemodynamics and PaCO2 were measured; CO2 removal was calculated while varying sweep gas flow rates (Qg), device blood flow rates (Qb), and PaCO2.

Results: Hemodynamic variables remained normal throughout the 72 hour study. CO2 removal increased with increases in Qg or Qb. Mean CO2 removal was 119.3 ml/min for Qb 1 L/ min, Qg 5 L/min, and PaCO2 40-50 mmHg. PaCO2 was directly proportional to CO2 clearance (R=0.72, p <0.001).

Conclusion: NOVALUNG iLA can provide near total CO2 removal with Qb 1-2 L/min, Qg 5 L/min, and minimal flow resistance (3.88+/-0.82 mmHg/L/min). PaCO2 correlates with CO2 removal and is dependent on Qb and Qg.