Objectives: Veno-arterial extracorporeal membrane oxygenation represents the last therapy option in refractory cardiogenic shock. Successful weaning becomes difficult if the myocardial function recovers but pulmonary impairment persists. We present our experience with a new weaning strategy, using a stepwise mode-switch from veno-arterial to veno-veno-arterial and veno-venous extracorporeal membrane oxygenation setting for patients with primary cardiogenic shock and subsequent respiratory failure.
Methods: From 81 patients treated with veno-arterial extracorporeal membrane oxygenation following acute cardiogenic shock between January 2014 and April 2018, eight patients with cardiac and pulmonary failure were identified to be treated using the following protocol: patients were put on veno-arterial extracorporeal membrane oxygenation, a second inflow cannula was inserted via the right jugular vein and cardiac weaning was performed via veno-veno-arterial support. Finally, patients were pulmonary weaned via veno-venous extracorporeal membrane oxygenation mode.
Results: In the mode-switch group, etiologies of cardiogenic shock were cardiac arrest (12.5%), myocardial infarction (12.5%) and post-cardiotomic heart failure (75%). Mean time between onset of cardiogenic shock and start of veno-arterial extracorporeal membrane oxygenation was 76 ± 117 min. At implantation, lactate and pH values were 9.5 ± 5.0 mmol/L and 7.2 ± 0.2. Total extracorporeal membrane oxygenation-time was 9.3 ± 4.7 days, with a mode-switch from veno-arterial to veno-veno-arterial after 3.9 ± 2.7 days. The weaning rate in the mode-switch group was 75% (vs. 41% in the entire cohort) and the 30-day survival was 50% (vs 32% in the cohort). 38% of the patients presented a favorable neurological outcome.
Conclusion: Mode-switch from veno-arterial to veno-veno-arterial and weaning via veno-venous extracorporeal membrane oxygenation mode is feasible for combined cardiac and pulmonary failure, with promising results due to an optimized pre-pulmonary oxygenation.
Keywords: cardiogenic shock; extracorporeal membrane oxygenation weaning; respiratory failure; veno-veno-arterial extracorporeal membrane oxygenation.