β-blockers to optimize peripheral oxygenation during extracorporeal membrane oxygenation: A case series

Objectives: Veno-venous extracorporeal membrane oxygenation (ECMO) is a well-established therapy in patients affected by respiratory failure and unresponsive to conventional therapy. Despite technical innovations, some limitations still exist, the most important one being refractory hypoxemia. This problem is linked partially to the mixture between patients' blood and ECMO fully oxygenated blood. In the present work, the reduction of cardiac output was proposed for the treatment of refractory hypoxemia in patients with high-flow ECMO and high endogenous cardiac output. Design: An observational study. Setting: A university hospital. Participants: Three consecutive patients suffering from persisting severe hypoxemia despite high-flow ECMO and with concomitant high cardiac output (>7 L/min). Intervention: A bolus dose of 500 μg/kg and a continuous infusion of esmolol was used and titrated to an SpO ₂ >92%. Measurements and Main Results: Esmolol administration was safe and highly beneficial in terms of peripheral oxygenation. PaO ₂ increased from 54 to 90 mmHg, from 50 to 94 mmHg, and from 49 to 66 mmHg during the first 12 hours of esmolol treatment in the 3 patients. Conclusions: In selected septic, tachycardic patients with a high cardiac output, veno-venous ECMO, led to improvement of peripheral oxygenation with the addition of a short-acting β-blocker infusion.