Clinical feasibility of "awake-ECMO” in acute respiratory failure

Introduction: Veno-venous extracorporeal membrane oxygenation (vv-ECMO) is nowadays safer due to recent technical improvements and thus is increasingly used as a rescue therapy for acute respiratory failure. Mechanical ventilation is the standard support for patient with respiratory failure, but can itself damage the lung. Objective: To explore vv-ECMO as an alternative to conventional mechanical ventilation in acute respiratory failure, we tested feasibility of vv-ECMO in spontaneous breathing patients (“awake- ECMO”). Methods: We retrospectively analyzed all consecutive patients who underwent vv-ECMO support from June 2012 to January 2015. Results: A total of 48 patients with acute respiratory failure (30 acute respiratory distress syndrome - ARDS, 7 acute exacerbation of chronic obstructive pulmonary disease - AECOPD, 11 end-stage pulmonary disease bridged to lung transplantation - ESPD) were analyzed. Figure shows the number of days on ECMO and on “awake-ECMO” for different patients’ categories. All ESPD and all out of one AECOPD patients were successfully treated while spontaneous breathing, whereas only 26% of ARDS patients could remove invasive ventilation and only during shorter time of ECMO support (p<0,001). Patients who could not undergo “awake-ECMO” were sicker than “awake” patients (SOFA 9.1±3.4 vs 4.5±1.3, p<0,001). Reasons underlying the impossibility of weaning from ventilator ARDS patients were pulmonary plasma-leakage (n=7), hemodynamic derangements (n=10), neurologic impairments (n=4), bleeding (n=7), severe respiratory distress and hypoxemia (n=8). Conclusion: vv-ECMO in awake spontaneous breathing patients is feasible as a bridge to lung transplantation and in AECOPD patients, while in sick ARDS patients we were not able to use vv- ECMO as an alternative to mechanical ventilation.