The influence of advanced age on venous-arterial extracorporeal membrane oxygenation outcomes

Ethical and health care economic concerns surround the use of venous-arterial extracorporeal membrane oxygenation (VA-ECMO) in elderly patients. Patients requiring VA-ECMO are often in critical condition and the decision to cannulate is time-sensitive. We investigated the relationship between age and VA-ECMO outcomes to better inform this decision.

This is a retrospective study of 355 patients placed on VA-ECMO between March 2007 and August 2016 at our institution. Using piecewise modelling, age became associated with in-hospital mortality after 63 years. Based on further analysis with the χ2 statistic maximization, patients were divided into 2 age groups: ≤72 years old [Group Y (Young), n = 310] and >72 years old [Group O (Old), n = 45]. Multivariable logistic regression was performed to identify preoperative predictors of in-hospital mortality.

Patients over the age of 72 had a significantly higher prevalence of comorbidities, including coronary disease, previous strokes and chronic kidney disease. Weaning from ECMO was achieved in 76% of Group Y and 47% of Group O (P < 0.001). In-hospital mortality was 52% among Group Y and 69% among Group O (P = 0.037). Multivariable logistic regression using preoperative risk factors identified coronary artery disease, acute decompensated heart failure and an age >72 years as independent predictors of mortality (age >72 years: odds ratio 2.71, 95% confidence interval 1.22-6.00; P = 0.01).

VA-ECMO in-hospital mortality is considerable across all age groups. However, age only becomes associated with mortality after 63 years and rises dramatically after 72 years. This study provides useful insight into these time-sensitive decisions for the development of possible practice guidelines.