The role of ECMO in COVID-19 acute respiratory failure: Defining risk factors for mortality.

BACKGROUND: Veno-venous extracorporeal membrane oxygenation (VV ECMO) utilization increased substantially during the COVID-19 pandemic, but without patient selection criteria. METHODS: We conducted a retrospective review of all adult patients with COVID-19-associated ARDS placed on VV ECMO at our institution from April 2020 through June 2022. RESULTS: 162 patients were included (n = 95 Pre-Delta; n = 58 Delta; n = 9 Omicron). The frequency of ECMO duration greater than three weeks was variable by pandemic period (17% pre-Delta, 41% Delta, 22% Omicron, p = 0.003). In-hospital mortality was 60.5%. Age ≥50 years (RR 1.28, 95% CI 1.01, 1.62), ≥7 days of respiratory support (1.39, 95% CI 1.05, 1.83) and pre-cannulation renal failure requiring dialysis (RR 1.42, 95% CI 1.13, 1.78) were associated with mortality. CONCLUSIONS: In this cohort of VV ECMO patients with COVID-19, older age, a longer duration of pre-ECMO respiratory support, and pre-ECMO renal failure all increased the risk of mortality by approximately 30%.

Posthospitalization outcomes after extracorporeal membrane oxygenation (ECMO) for COVID-19.

BACKGROUND: Critical illness from COVID-19 is associated with prolonged hospitalization and high mortality rates. Extracorporeal membrane oxygenation is used for refractory severe acute respiratory distress syndrome in COVID-19 with outcomes comparable to other indications for extracorporeal membrane oxygenation. However, long-term functional outcomes have yet to be fully elucidated. METHODS: We performed a retrospective chart review of 24 consecutive patients who required extracorporeal membrane oxygenation due to COVID-19 associated severe acute respiratory distress syndrome and survived to hospital discharge. After hospitalization, we contacted patients and administered the Patient-Reported Outcomes Measurement Information System (PROMIS) Global-10 tool to assess longer-term outcomes. We abstracted demographics, clinical course, outcomes, and disposition variables from the electronic medical record. Descriptive statistical analysis was used on the retrospective data collection. RESULTS: Inpatient data were analyzed for 24 patients, and 21 of 24 (88%) patients completed the Patient-Reported Outcomes Measurement Information System tool at an average of 8.8 months posthospitalization. At hospital discharge, 62.5% of patients had ongoing oxygen requirements (nasal cannula, trach collar, or mechanical ventilation); 70.8% were discharged to a location other than home. However, at the time of follow-up, only 9.5% of patients required supplemental oxygen, all tracheostomies had been removed, and all patients resided at home. Patients reported relatively high levels of global physical function, and though there was a high reported incidence of fatigue, overall pain scores were low. CONCLUSION: Long-term outcomes after extracorporeal membrane oxygenation for severe acute respiratory distress syndrome from coronavirus disease 2019 are promising. Extracorporeal membrane oxygenation therapy may confer morbidity benefits in patients with coronavirus disease and remains a valuable modality with excellent functional outcomes and preserved quality of life for survivors.

Comparative outcomes between COVID-19 and influenza patients placed on veno-venous extracorporeal membrane oxygenation for severe ARDS.

BACKGROUND: ECMO is an established supportive adjunct for patients with severe, refractory ARDS from viral pneumonia. However, the exact role and timing of ECMO for COVID-19 patients remains unclear. METHODS: We conducted a retrospective comparison of the first 32 patients with COVID-19-associated ARDS to the last 28 patients with influenza-associated ARDS placed on V-V ECMO. We compared patient factors between the two cohorts and used survival analysis to compare the hazard of mortality over sixty days post-cannulation. RESULTS: COVID-19 patients were older (mean 47.8 vs. 41.2 years, p = 0.033), had more ventilator days before cannulation (mean 4.5 vs. 1.5 days, p < 0.001). Crude in-hospital mortality was significantly higher in the COVID-19 cohort at 65.6% (n = 21/32) versus 36.3% (n = 11/28, p = 0.041). The adjusted hazard ratio over sixty days for COVID-19 patients was 2.81 (95% CI 1.07, 7.35) after adjusting for age, race, ECMO-associated organ failure, and Charlson Comorbidity Index. CONCLUSION: ECMO has a role in severe ARDS associated with COVID-19 but providers should carefully weigh patient factors when utilizing this scarce resource in favor of influenza pneumonia.

Time to Cannulation after ICU Admission Increases Mortality for Patients Requiring Veno-venous ECMO for COVID-19 Associated Acute Respiratory Distress Syndrome.

OBJECTIVE: COVID-19 can cause ARDS that is rapidly progressive, severe, and refractory to conventional therapies. ECMO can be used as a supportive therapy to improve outcomes but evidence-based guidelines have not been defined. SUMMARY BACKGROUND DATA: Initial mortality rates associated with ECMO for ARDS in COVID-19 were high, leading some to believe that there was no role for ECMO in this viral illness. With more experience, outcomes have improved. The ideal candidate, timing of cannulation, and best postcannulation management strategy, however, has not yet been defined. METHODS: We conducted a retrospective review from April 1 to July 31, 2020 of the first 25 patients with COVID-19 associated ARDS placed on V-V ECMO at our institution. We analyzed the differences between survivors to hospital discharge and those who died. Modified Poisson regression was used to model adjusted risk factors for mortality. RESULTS: Forty-four patients (11/25) survived to hospital discharge. Survivors were significantly younger (40.5 years vs 53.1 years; P < 0.001) with no differences between cohorts in mean body mass index, diabetes, or PaO2:-FiO2 at cannulation. Survivors had shorter duration from symptom onset to cannulation (12.5 days vs 19.9 days, P = 0.028) and shorter duration of intensive care unit (ICU) length of stay before cannulation (5.6 days vs 11.7 days, P = 0.045). Each day from ICU admission to cannulation increased the adjusted risk of death by 4% and each year increase in age increased the adjusted risk 6%. CONCLUSIONS: ECMO has a role in severe, refractory ARDS associated with COVID-19. Increasing age and time from ICU admission were risk factors for mortality and should be considered in patient selection. Further studies are needed to define best practices for V-V ECMO use in COVID-19.