RESUMO
Objectives: It is well known that severe COVID-19 is associated with complex immunological and inflammatory dysregulation. Both these physiopathological events translate to a high risk of major thrombotic or hemorrhagic events. In patients treated with venovenous extracorporeal membrane oxygenation (VVECMO), membrane dysfunction might affect systemic oxygenation and limit its duration-expectancy. This study aimed to assess the possible causes of extracorporeal membrane failure in COVID-19 patients and its impact on outcome. Method(s): Retrospective, single-center, observational case-control study involving adult COVID-19 patients admitted to an ECMO referral centre in a tertiary university hospital. All patients required VVECMO for acute respiratory failure, including 48 cases who needed one or more extracorporeal membrane exchanges and 45 controls (no membrane exchange). These two groups were compared for demographic characteristics, severity of the disease using validated scores (SAPS II and SOFA), duration of ECMO run, coagulation assessment, cumulative anticoagulation dose, associated complications, and outcomes (ICU and hospital mortality). Result(s): Most patients were males (71.0%) and younger than 50 years (79.5%). Median ECMO run duration was significantly longer in the case group (35.0 vs 14.0 days, p <0.001), as well as ICU length-of-stay (45.5 vs 28 days, p <0.001). Membrane exchange tended to be associated with sepsis (56% vs 33%, p=0.037), major hemorrhage (58% vs 43%, p=0.022), heparin-induced thrombocytopenia (25% vs 9%, p=0.054), higher D-dimer title (17.36 ng/dL vs 7.5 ng/dL, p=0.07) and lower platelet counts (133.000/muL vs 154.000/muL). Median SAPS II (32.0 vs 33.0, p=0.20) and the mortality (27% vs 24%, p >0.99) were similar between these groups. Conclusion(s): In patients with SARS-CoV-2 pneumonia and severe hypoxemia treated with VVECMO support the emergence of infection, coagulopathy and inflammation were associated with high risk of membrane dysfunction. No impact on mortality could be confirmed from these data. Anticoagulation monitoring and dosing strategies should be reinforced to promote membrane protection.
RESUMO
Objectives: Airway hemorrhage (AH) frequently complicates extracorporeal membrane oxygenation (ECMO) treatment. Inflammation, coagulopathy and antithrombotic therapy are contributing factors. Patients with COVID-19- associated ARDS (CARDS) supported with ECMO present all these features. We aim to characterize the incidence and the clinical and prognostic impact of AH. Method(s): Review of a cohort of patients with CARDS treated with ECMO support at a single ECMO centre between March 2020-February 2022 (n=92). AH was defined as a clinically significant hemorrhage fit demanded interruption of anticoagulation, transfusional support or bronchoscopy. Univariate analysis was performed using GraphPadPrism. Result(s): One third (n= 31) of patients with CARDS treated with ECMO had clinically significant AH. Patients who developed AH had significantly longer ICU length-of-stay (LoS), ECMO run and invasive mechanical ventilation (IMV) duration. Significant differences in coagulation and inflammatory markers were detected between patients with early (<72h) versus late (>9 days) onset of AH (Table 1). Mortality at day 90, demographics, comorbidities, CT scan pattern and clinical severity indexes were similar between patients with and without AH (NAH). Conclusion(s): In patients with severe CARDS treated with ECMO support, the occurrence of airway hemorrhage leads to clinically important morbidity but does not increase mortality. Distinct pathways may be involved in the development of early v. late AH. (Table Presented).