Evaluation of a New Extracorporeal CO₂ Removal Device in an Experimental Setting

Ultra-protective lung ventilation in acute respiratory distress syndrome or early weaning and/or avoidance of mechanical ventilation in decompensated chronic obstructive pulmonary disease may be facilitated by the use of extracorporeal CO₂ removal (ECCO₂R). We tested the CO₂ removal performance of a new ECCO₂R (CO₂RESET) device in an experimental animal model.

Three healthy pigs were mechanically ventilated and connected to the CO₂RESET device (surface area = 1.8 m², EUROSETS S.r.l., Medolla, Italy). Respiratory settings were adjusted to induce respiratory acidosis with the adjunct of an external source of pure CO₂ (target pre membrane lung venous PCO₂ (P_preCO₂): 80-120 mmHg). The amount of CO₂ removed (VCO₂, mL/min) by the membrane lung was assessed directly by the ECCO₂R device.

Before the initiation of ECCO₂R, the median P_preCO₂ was 102.50 (95.30-118.20) mmHg. Using fixed incremental steps of the sweep gas flow and maintaining a fixed blood flow of 600 mL/min, VCO₂ progressively increased from 0 mL/min (gas flow of 0 mL/min) to 170.00 (160.00-200.00) mL/min at a gas flow of 10 L/min. In particular, a high increase of VCO₂ was observed increasing the gas flow from 0 to 2 L/min, then, VCO₂ tended to progressively achieve a steady-state for higher gas flows. No animal or pump complications were observed.

Medium-flow ECCO₂R devices with a blood flow of 600 mL/min and a high surface membrane lung (1.8 m²) provided a high VCO₂ using moderate sweep gas flows (i.e., >2 L/min) in an experimental swine models with healthy lungs.