Indication for Venovenous Extracorporeal Membrane Oxygenation: Is 65 Years Old, Too Old?

To the Editor:

We read with interest the paper by Deatrick et al.¹ published in the Journal. The authors assessed the impact of age on mortality for patients on venovenous extracorporeal membrane oxygenation (V-V ECMO) and found that it represents an independent predictor of survival at hospital discharge. Deatrick et al.¹ reported an extremely low survival rate in the (very) small subgroup of patients of 65 years of age and older treated with V-V ECMO support. To confirm these findings, we retrospectively analyzed data of V-V ECMO patients admitted from August 2009 to November 2019 to our ICU, excluding patients under 18 years of age. ANOVA or Wilcoxon test were used to compare baseline variables between groups. Mortality rates at hospital discharge were compared by means of Pearson’s χ² test. One hundred forty-four ppts were treated with V-V ECMO in the study period. Overall hospital mortality was 30.5%. Table 1, Supplemental Digital Content, http://links.lww.com/ASAIO/A541 shows baseline parameters and outcomes of the study population stratified by age.

Despite no difference in severity scores at baseline, higher mortality was observed in older patients, in accordance with the findings of Deatrick et al. However, in contrast to their results, an acceptable survival rate (56%) was recorded in patients over 65 years of age, consistent with other previous studies.² Except for hypertension, which was present in 69% of patients over 65, patients in this subgroup had few comorbidities: 26% of patients had diabetes, 23% autoimmune disease, 15% chronic heart failure, 8% chronic obstructive pulmonary disease, 7% chronic liver disease, and 7% immunodepression. No patient had active malignancies, peripheral vasculopathy, or chronic renal disease.

Age is a well-known risk factor for mortality in critical patients.^3–5 ECMO represent one of the most invasive procedure in the critical patients, and its application in elderly patients might be associated with poor outcome.^1,6 Specific scores^7,8 have been developed to predict mortality risk in patients with acute respiratory distress syndrome treated with ECMO. Narrowing indications for ECMO to patients with few comorbidities and good performance status at baseline may allow to obtain acceptable survival rates in older patients (i.e., 60–70 years). Our data and previous literature² show that almost one out of two V-V ECMO patients over 65 years of age can be discharged alive from the hospital. Therefore, in our opinion, age over 65 should not be considered a firm contraindication for the use of ECMO.