Predicting Survival for Patients Receiving Extracorporeal Membrane Oxygenation

Beat J. Meyer, MD reviewing Schmidt M et al. Eur Heart J 2015 Sep 1.

An internationally derived pre-ECMO risk model appears clinically useful.

Extracorporeal membrane oxygenation (ECMO) is an effective treatment option in refractory, yet potentially reversible, cardiogenic shock. Because of its high rates of severe complications and high costs, patient selection on the basis of a predictive survival model could improve quality of care. Analyzing registry data from the Extracorporeal Life Support Organizations (160 U.S. and 120 other centers), researchers used multivariate logistic regression to identify pre-ECMO survival variables and develop a risk score.

Of 3846 patients with refractory cardiogenic shock treated with ECMO (mean age, 54; 67% male), 1601 (42%) were alive at hospital discharge. Pre-ECMO factors associated with mortality were chronic renal failure, longer duration of mechanical ventilation, organ failures, cardiac arrest, congenital heart disease, lower pulse pressure, and lower serum bicarbonate. By contrast, protective factors were younger age, weight between 76 and 89 kg, acute myocarditis, heart transplant, refractory ventricular tachycardia or fibrillation, higher diastolic blood pressure (starting at 40 mm Hg), and peak inspiratory pressure ≤20 cm H2O. The investigators included internally validated variables with P values ≤0.05 in the model to construct the survival after veno-arterial-ECMO (SAVE) score. In an external validation cohort of 161 Australian patients, the performance of the SAVE score was excellent and compared favorably with established intensive-care mortality risk scores.

Citation(s):

Schmidt M et al. Predicting survival after ECMO for refractory cardiogenic shock: The survival after veno-arterial-ECMO (SAVE)-score. Eur Heart J 2015 Sep 1; 36:2246.