Increasing Mortality in Venovenous Extracorporeal Membrane Oxygenation for COVID-19–Associated Acute Respiratory Distress Syndrome

Abstract

OBJECTIVES:Determine the factors associated with mortality in venovenous extracorporeal membrane oxygenation (V-V ECMO) patients with COVID-19 infection and provide an updated report of clinical outcomes for patients treated with V-V ECMO for COVID-19 in Minnesota. DESIGN:Multicenter prospective observational study. SETTING:The four adult Extracorporeal Life Support Organization-certified Centers of Excellence in Minnesota. PATIENTS:A total of 100 patients treated with V-V ECMO for COVID-19-associated acute respiratory distress syndrome (ARDS) from March 2020 to May 2021. INTERVENTIONS: Not applicable. MEASUREMENTS AND MAIN RESULTS:The primary outcome was 60-day survival for patients treated with V-V ECMO for COVID-19. Outcomes of patients treated from November 2020 to May 2021(cohort 2) were compared with data from a previous cohort of patients, collected from March 2020 to October 2020 (cohort 1). The data from both cohorts were merged into a single dataset (Combined Cohort). Survival on V-V ECMO due to COVID-19-associated ARDS significantly decreased after October 2020 (63% vs 41%; p = 0.026). The median interval from hospital admission to V-V ECMO cannulation was significantly associated with 60-day mortality (10 d [6-14 d] in nonsurvivors vs 7 d [4-9 d] in survivors; p = 0.001) in the Combined Cohort and was also significantly longer in cohort 2 than cohort 1 (10 d [7-14 d] vs 6 d [4-10 d]; p < 0.001). In the Combined Cohort, the 60-day survival for patients who did not receive steroids was 86% (n = 12) versus 45% (n = 39) for patients who received at least one dose of steroids (p = 0.005). CONCLUSIONS:There was a significant increase in mortality for patients treated with V-V ECMO for COVID-19-associated ARDS in cohort 2 compared with cohort 1. Further research is required to determine the cause of the worsening trend in mortality.

Prognostic factors associated with mortality among patients receiving venovenous extracorporeal membrane oxygenation for COVID-19: a systematic review and meta-analysis

“…Of 2888 studies identified ( figure ), we selected 123 for full-text review. We included 42 observational cohort studies 13 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 involving 17 449 patients ( table 1 ), predominantly from North America or Europe. We did not identify any randomised controlled trials that met our eligibility criteria.…”

“… 35 , 36 , 37 , 38 , 39 Studies were judged to be at some risk of bias for confounding adjustment and for statistical analysis and reporting if they did not account for clinically important confounders using either logistic regression or Cox proportional hazards models. 15 , 39 , 44 , 46 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 Studies reporting adjusted analyses were judged to be at some risk of bias for statistical analysis 35 , 36 , 37 , 40 , 41 , 42 , 43 , 44 , 45 , 46 if they did not adhere to methodological standards set by the PROGRESS guidelines, 19 , 20 , 21 , 22 in particular with regards to a priori selection of clinically important confounders and consideration of an appropriate sample size to minimise potential overfitting. 28 , 76 The composition and methodological quality of individual prediction models for each study and funnel plots used to evaluate for publication bias among variables that were assessed in at least ten studies are included in the appendix (p 36–41 ).…”

“… 45 Similarly, when the effect of age was measured in 10-year increments in eight studies, 35 , 40 , 41 , 42 , 44 , 60 , 69 , 73 older age remained associated with mortality (aOR 1·19 [95% CI 1·11–1·27]). Of the 26 studies 36 , 37 , 39 , 40 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 58 , 60 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 71 , 74 that included sex as a prognostic factor, male sex was found to be probably associated with increased mortality (uOR 1·34 [95% CI 1·20–1·49]; moderate certainty) and of the three studies 13 , 35 , 71 that included lung disease as a prognostic factor, chronic lung disease was found to be probably associated with increased mortality (aHR 1·55 [95% CI 1·20–2·00]; moderate certainty). In the 14 studies 35 , 41 , 49 , 51 , 54 , 55 , 61 , 62 , 66 , 67 , 68 , 72 , 73 , 74 that included obesity as a prognostic factor, obesity may have been associated with decreased mortality (uOR 0·84 [0·72–0·97]), although this finding was based on low-certainty evidence with a serious risk of bias and imprecision.…”

“…Of the 26 studies 36 , 37 , 39 , 40 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 58 , 60 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 71 , 74 that included sex as a prognostic factor, male sex was found to be probably associated with increased mortality (uOR 1·34 [95% CI 1·20–1·49]; moderate certainty) and of the three studies 13 , 35 , 71 that included lung disease as a prognostic factor, chronic lung disease was found to be probably associated with increased mortality (aHR 1·55 [95% CI 1·20–2·00]; moderate certainty). In the 14 studies 35 , 41 , 49 , 51 , 54 , 55 , 61 , 62 , 66 , 67 , 68 , 72 , 73 , 74 that included obesity as a prognostic factor, obesity may have been associated with decreased mortality (uOR 0·84 [0·72–0·97]), although this finding was based on low-certainty evidence with a serious risk of bias and imprecision. Obesity was most commonly defined 43 , 44 , 49 , 54 , 61 , 66 , 68 , 72 , 73 as a BMI of at least 30 kg/m 2 , although it was also defined as at least 40 kg/m 2 in one study, 71 and was not explicitly defined in others.…”

Venovenous extracorporeal membrane oxygenation for severe COVID-19 pneumonitis: case series from a Hungarian tertiary centre

“…Interestingly, results from the rst wave seem to be better than that achieved later, which may be associated with timing. Braaten found a signi cantly worse survival after October 2020, and, of note, the median interval from hospital admission to V-V ECMO initiation was longer in that cohort (10 days vs 6 days) and it was associated with 60-day mortality [15]. The pooled mean duration of IMV prior to ECMO initiation was 4.4 days in Ramanathan's metaanalysis, but it was not associated with mortality [13].…”