Clinical risk factors of extracorporeal membrane oxygenation support in older adults

The ageing population and the expected increase in the number of elderly patients make an evidence-based assessment of Extracorporeal Membrane Oxygenation (ECMO) therapy in old patients progressively more important. Veno-arterial (VA) ECMO results for patient aged <65 years is well known. However, the risk profile and in-hospital prognosis of advanced age patients with ECMO still need more investigation. The aim of this study was to identify risk factors that predicted the outcomes for elderly patients who received VA-ECMO.

In this retrospective study, medical records for patients with ECMO aged 65 years and over were collected between 2009 and 2012 at a tertiary hospital.

A total of 99 patients (mean age: 76.4±6.4 years) were included. The most common condition requiring VA-ECMO support was cardiogenic shock. Among survivors on VA-ECMO, 28 (28.3%) patients were successfully weaned from support. Thirteen (13.1%) patients were successfully discharged. We found that cardiogenic shock (OR = 3.158, P = 0.013), acute physiology and chronic health evaluation II (APACHE II) score (OR = 1.147, P<0.001), and simplified acute physiology score II (SAPS II) score (OR = 1.054, P = 0.001) were risk factors associated with survival on VA-ECMO. By using the areas under the receiver operating characteristic (AUC) curve, the APACHE II score and SAPS II score displayed acceptable discriminative power (AUC 0.722; 0.715, respectively).

Our findings indicate that the risk of mortality increases with cardiogenic shock, higher APACHE II score, and higher SAPS II score. These risk factors can be utilized as potential predictors to identify the potential candidates for ECMO support.