Survival and Ability to Return to Work 1 Year After Extracorporeal Membrane Oxygenation for Acute Heart or Lung Failure

Patients experiencing acute or end-stage heart or lung failure continue to display a high mortality rate, which ranges between 40–55% across various disease aetiologies, countries and studies.1 One invasive procedure for providing short-term support in critically ill patients involves extracorporeal membrane oxygenation (ECMO).2, 3 Especially in cardiogenic shock associated with acute myocardial infarction mortality remains high despite early mechanical circulatory support.4, 5 Previous studies on the outcomes of ECMO therapy have focussed mainly on survival,1-5 while there is a paucity of data on physical impairment and the capability to return to work in this particular patient cohort. The current study focussed on the post-ECMO survival and subsequent work capacity among patients who underwent ECMO therapy. Furthermore, we sought to identify predictive factors associated with survival and the ability to return to work. The present analysis of our prospective, hospital-based ECMO registry reports survival 28 and 365 days after ECMO initiation and the ability to return to work after 365 days. The occupational status was obtained during telephone surveys and was recorded as full-time, part-time, retired, unemployed, housekeeper, and unable to work. Quality of life (QoL) was assessed by using a visual analogue scale ranging from 0 (lowest possible QoL) and 10 (highest possible QoL) points. The registry was approved by the local institutional review board (no. 2997–2016). Informed consent was obtained from survivors or their legal guardians; a waiver was issued for patients who died before informed consent could be obtained. IBM SPSS Statistics 28.0 (IBM Corp, Armonk, NY, USA) and STATA 13.0 (State Corp. LP, College Station, TX, USA) were used for statistical analysis. Categorical variables are reported as numbers and shown as median (interquartile range [IQR]) unless indicated otherwise. Survival was analysed using Kaplan–Meier survival curves. Association between survival and patient characteristics (age at implantation, patients' sex, diagnosis, need for extracorporeal cardiopulmonary resuscitation (eCPR), smoking history including pack-years, comorbidities and body mass index) were analysed by univariable und multivariable Cox proportional hazard models. A p-value <0.05 was considered statistically significant and all reported p-values are two-sided. Between May 2017 and October 2021, 456 patients (>18 years old) received either veno-arterial (VA) (n = 228, 50%) or veno-venous (VV) (n = 228, 50%) ECMO for respiratory or cardiac failure at Hannover Medical School. Main indications for VV-ECMO were acute respiratory distress syndrome due to pneumonia (n = 141, 62%) and sepsis (n = 76, 33%). Main indications for VA-ECMO were ischaemic (n = 82, 36%) or non-ischaemic (n = 91, 40%) heart failure, and pulmonaryembolism (n = 32, 14%); of which n = 78 patients received eCPR. The median (IQR) age was 51 (41–59) years; 30.7% were female and 69.3% male. A total of 185 of 456 (40.6%) patients were alive at 28 days, and 148 of 456 (32.5%) patients were alive at 365 days. The 28-day and 365-day survival rates of patients receiving VA-ECMO (eCPR excluded) were 38.7% and 30%, respectively. Patients undergoing eCPR and VA-ECMO had 28-day and 365-day survival rates of 20.5% and 17.9%, respectively. The corresponding numbers in patients receiving VV-ECMO were 48.7% and 39.9%, respectively. Of the 148 survivors, 38 (25.6%) were lost to follow-up, leaving 110 patients with 365 days of follow-up information available. Of those, 37 (33.6%) were able to work, 16 (14.5%) were retired and 57 (51.8%) were unable to work due to disability (Figure 1). QoL after 1 year was 6.6 ± 1.9 across all ECMO groups: 6.7, 6.3 and 6.6 for VV-ECMO, VA-ECMO and VA-ECMO + eCPR, respectively. Predictors of death at 1 year were eCPR (hazard ratio [HR] 2.15, 95% confidence interval [CI] 1.63–2.84, p = 0.001) and age (HR 1.02, 95% CI 1.01–1.03, p < 0.0001). These two variables were also the only independent predictors of death or the inability to return to work (HR 1.02, 95% CI 1.01–1.03, p < 0.0001 and 1.78, 95% CI 1.36–2.32, p < 0.0001). Our data reinforce that severe respiratory or cardiac failure requiring the need for ECMO support remains associated with a high risk of death, which is underscored by a 1-year mortality rate of 67% in the present series. Moreover, in our series only about one third of patients who survived were able to return to work, which is even less than what has been reported in previous series where up to 83% of ECMO survivors were able to return to work.6-8 In our study, age and eCPR were the only independent factor predicting the likelihood to survive and return to work. QoL of survivors was overall good and comparable to previous studies. The main limitations of our study are the single centre setting and the fact that we were unable to retrieve follow-up data from about a quarter of the patients who were discharged from our hospital. Taken together, in this single-centre series of 456 patients requiring ECMO support for acute heart or lung failure, 1-year survival was 32.5%. Roughly one third (34%) of the survivors were able to return to work. These findings underscore the need for further research to identify better predictors of survival and to improve long-term outcomes of ECMO therapy. The study was supported by the Deutsche Forschungsgemeinschaft, KFO 311. Conflict of interest: none declared. Open Access funding enabled and organized by Projekt DEAL.