Expert perspectives on ECCO2R for acute hypoxemic respiratory failure: consensus of a 2022 European roundtable meeting.

Background: By controlling hypercapnia, respiratory acidosis, and associated consequences, extracorporeal CO₂ removal (ECCO₂R) has the potential to facilitate ultra-protective lung ventilation (UPLV) strategies and to decrease injury from mechanical ventilation. We convened a meeting of European intensivists and nephrologists and used a modified Delphi process to provide updated insights into the role of ECCO₂R in acute respiratory distress syndrome (ARDS) and to identify recommendations for a future randomized controlled trial.

Results: The group agreed that lung protective ventilation and UPLV should have distinct definitions, with UPLV primarily defined by a tidal volume (V_T) of 4-6 mL/kg predicted body weight with a driving pressure (ΔP) ≤ 14-15 cmH₂O. Fourteen (93%) participants agreed that ECCO₂R would be needed in the majority of patients to implement UPLV. Furthermore, 10 participants (majority, 63%) would select patients with PaO₂:FiO₂ > 100 mmHg (> 13.3 kPa) and 14 (consensus, 88%) would select patients with a ventilatory ratio of > 2.5-3. A minimum CO₂ removal rate of 80 mL/min delivered by continuous renal support machines was suggested (11/14 participants, 79%) for this objective, using a short, double-lumen catheter inserted into the right internal jugular vein as the preferred vascular access. Of the participants, 14/15 (93%, consensus) stated that a new randomized trial of ECCO₂R is needed in patients with ARDS. A ΔP of ≥ 14-15 cmH₂O was suggested by 12/14 participants (86%) as the primary inclusion criterion.

Conclusions: ECCO₂R may facilitate UPLV with lower volume and pressures provided by the ventilator, while controlling respiratory acidosis. Since recent European Society of Intensive Care Medicine guidelines on ARDS recommended against the use of ECCO₂R for the treatment of ARDS outside of randomized controlled trials, new trials of ECCO₂R are urgently needed, with a ΔP of ≥ 14-15 cmH₂O suggested as the primary inclusion criterion.