Effect of Heart Rate Control with Esmolol on Oxygen Metabolism and Clinical Outcomes in VVECMO patients: a Multicenter, Prospective, Randomized Controlled Study

Background Veno-venous extracorporeal membrane oxygenation (VV ECMO) has been widely used in patients with respiratory failure. For patients with refractory hypoxemia treated with VV ECMO, β-blockers can improve oxygenation by reducing cardiac output (CO) and increasing ECMO flow /CO ratio. However, it has been suggested that β-blockers aggravate tissue hypoxia by reducing systemic oxygen delivery (DO2) by controlling heart rate. Therefore, the effect of heart rate control by esmolol on oxygen metabolism and clinical outcomes in VV ECMO patients is still controversial and needs further study. Methods This study was a randomized (1:1), prospective, multi-center, parallel controlled clinical study. Patients with acute respiratory distress syndrome (ARDS) were treated with VV ECMO. After signing the informed consent form and meeting the inclusion/exclusion criteria, patients will be randomly assigned to the esmolol group or the control group, with 60 patients in each group, for a total of 120 patients to be recruited. The primary endpoint was 28-day survival. Secondary endpoints included oxygen metabolism, ventilator parameters (lung-protective ventilation), norepinephrine equivalent, duration of mechanical ventilation, length of ICU stay, and length of hospital stay. Discussion 1. To investigate the effect of heart rate control by β-blocker on 28-day survival rate in VV ECMO patients; 2. To investigate the effect of heart rate control by β-blockers on circulation in VV ECMO patients and whether lowering DO2 causes tissue hypoxia.