ABSTRACT
Objectives: Death from SARS-CoV-2 pneumonia resulted from progressive respiratory failure in most patients. Whenever accessible, venovenous extracorporeal membrane oxygenation (VVECMO) was implemented to rescue patients with refractory hypoxemia. Reported mortality in this population reached values from 20 to 50 percent, but the direct causes of death were not so widely acknowledged. The aim of our study was to characterize mortality in patients treated with VVECMO support. Method(s): Retrospective review of a prospectively collected database in an ECMO referral centre. All patients with diagnosis of SARS-CoV-2 infection treated with VVECMO support were included. Survivors and nonsurvivors were compared using t-student and chi2 methods. A Cox regression analysis was performed to identify predictors of mortality at admission. Result(s): Ninety-three patients were included (29% female). Median age was 54+/-12 years, mean SOFA was 5.7+/-2.9 and SAPS II was 35.6+/-13.6. Hospital mortality was 24.7%. Main causes of death were septic shock in 39.1% (9 patients), irreversible lung fibrosis 30.4% (7 patients) and catastrophic hemorrhage in 4.3% (4 patients). End-of-life care measures (withdrawal or withholding) were adopted in 65.2% of non-survivals. Patients who died were older (55 vs 48 years, p<0.05), had longer disease course (19 vs 15.3 days, p<0.05), longer invasive mechanical ventilation course before cannulation (8.5 vs 5 days, p<0.05), lower static lung compliance (25.5 vs 31.8 mL/cmH2O, p<0.05) and were ventilated with lower PEEP (8 vs 10 cmH2O, p<0.05) on cannulation. On a Cox-regression model, only prone ventilation before cannulation (HR 9,7;CI 95% 1,4- 68,6;p<0.05) and SAPS II (HR 1.04;CI 95% 1,001- 1,083;p<0.05) predicted mortality. Conclusion(s): Mortality in patients with severe SARSCoV-2 pneumonia treated with VVECMO was exceedingly low in our study, when compared with other series. Only one-third died from progressive lung disease, which suggests that protocol improvement can further reduce mortality.