A Comparison of Long-Term Outcomes in Patients Managed With Venovenous Extracorporeal Membrane Oxygenation in the First and Second Waves of the COVID-19 Pandemic in the United Kingdom.

OBJECTIVES: Early studies of venovenous extracorporeal membrane oxygenation (ECMO) in COVID-19 have revealed similar outcomes to historical cohorts. Changes in the disease and treatments have led to differences in the patients supported on venovenous ECMO in the first and second waves. We aimed to compare these two groups in both the acute and follow-up phase. DESIGN: Retrospective single-center cohort study comparing mortality at censoring date (November 30, 2021) and decannulation, patient characteristics, complications and lung function and quality of life (QOL-by European Quality of Life 5 Dimensions 3 Level Version) at first follow-up in patients supported on venovenous ECMO between wave 1 and wave 2 of the COVID-19 pandemic. SETTING: Critical care department of a severe acute respiratory failure service. PATIENTS: Patients supported on ECMO for COVID-19 between wave 1 (March 17, 2020, to August 31, 2020) and wave 2 (January 9, 2020, to May 25, 2021). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One hundred twenty-three patients were included in our analysis. Survival at censoring date (χ 2 , 6.35; p = 0.012) and decannulation (90.4% vs 70.0%; p < 0.001) was significantly lower in the second wave, while duration of ECMO run was longer (12.0 d [18.0-30.0 d] vs 29.5 d [15.5-58.3 d]; p = 0.005). Wave 2 patients had longer application of noninvasive ventilation (NIV) prior to ECMO and a higher frequency of barotrauma. Patient age and NIV use were independently associated with increased mortality (odds ratio 1.07 [1.01-1.14]; p = 0.025 and 3.37 [1.12-12.60]; p = 0.043, respectively). QOL and lung function apart from transfer coefficient of carbon monoxide corrected for hemoglobin was similar at follow-up across the waves. CONCLUSIONS: Most patients with COVID-19 supported on ECMO in both waves survived in the short and longer term. At follow-up patients had similar lung function and QOL across the two waves. This suggests that ECMO has an ongoing role in the management of a carefully selected group of patients with COVID-19.

Thoracic surgery in patients on veno-venous extracorporeal membrane oxygenation for COVID-19 associated acute respiratory distress syndrome.

OBJECTIVES: The COVID-19 pandemic has generated a new type of acute respiratory distress syndrome (ARDS) arising as a complication of COVID-19 pneumonia. Extreme cases require the support of extracorporeal membrane oxygenation (ECMO). Here we present the outcomes of patients that underwent surgical tracheostomy or thoracic surgery at a single tertiary centre whilst on ECMO support for COVID-19 related ARDS. METHODS: 18 patients requiring thoracic input whilst on ECMO support during the first wave of COVID-19 (March-June 2020) were included. Thoracic surgery was required both for performing surgical tracheostomies in the operating theatre and for treating emergencies arising under the ECMO treatment such as bleeding complications. RESULTS: Thirteen patients underwent a surgical tracheostomy, whilst five patients had an invasive thoracic procedure. Anticoagulation was withheld for at least 12 h in the perioperative setting regardless of the indication. One patient was re-operated for haemothorax immediately after the end of the primary operation. 94.5% of the patients were successfully decannulated from ECMO support. Overall 30-day mortality in the cohort was 5.5% (1/18). CONCLUSIONS: Thoracic surgeons can play a valuable role in supporting an ECMO unit during the COVID pandemic, by treating ECMO related complications and by safely performing surgical tracheostomies. Withholding anticoagulation in the perioperative window was not associated with increased thromboembolic events and is desirable when interventions or surgery is indicated in this patient cohort to avoid excessive bleeding.

In-hospital and 6-month outcomes in patients with COVID-19 supported with extracorporeal membrane oxygenation (EuroECMO-COVID): a multicentre, prospective observational study.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has been widely used in patients with COVID-19, but uncertainty remains about the determinants of in-hospital mortality and data on post-discharge outcomes are scarce. The aims of this study were to investigate the variables associated with in-hospital outcomes in patients who received ECMO during the first wave of COVID-19 and to describe the status of patients 6 months after ECMO initiation. METHODS: EuroECMO-COVID is a prospective, multicentre, observational study developed by the European Extracorporeal Life Support Organization. This study was based on data from patients aged 16 years or older who received ECMO support for refractory COVID-19 during the first wave of the pandemic-from March 1 to Sept 13, 2020-at 133 centres in 21 countries. In-hospital mortality and mortality 6 months after ECMO initiation were the primary outcomes. Mixed-Cox proportional hazards models were used to investigate associations between patient and management-related variables (eg, patient demographics, comorbidities, pre-ECMO status, and ECMO characteristics and complications) and in-hospital deaths. Survival status at 6 months was established through patient contact or institutional charts review. This study is registered with ClinicalTrials.gov, NCT04366921, and is ongoing. FINDINGS: Between March 1 and Sept 13, 2020, 1215 patients (942 [78%] men and 267 [22%] women; median age 53 years [IQR 46-60]) were included in the study. Median ECMO duration was 15 days (IQR 8-27). 602 (50%) of 1215 patients died in hospital, and 852 (74%) patients had at least one complication. Multiorgan failure was the leading cause of death (192 [36%] of 528 patients who died with available data). In mixed-Cox analyses, age of 60 years or older, use of inotropes and vasopressors before ECMO initiation, chronic renal failure, and time from intubation to ECMO initiation of 4 days or more were associated with higher in-hospital mortality. 613 patients did not die in hospital, and 547 (95%) of 577 patients for whom data were available were alive at 6 months. 102 (24%) of 431 patients had returned to full-time work at 6 months, and 57 (13%) of 428 patients had returned to part-time work. At 6 months, respiratory rehabilitation was required in 88 (17%) of 522 patients with available data, and the most common residual symptoms included dyspnoea (185 [35%] of 523 patients) and cardiac (52 [10%] of 514 patients) or neurocognitive (66 [13%] of 512 patients) symptoms. INTERPRETATION: Patient's age, timing of cannulation (<4 days vs ≥4 days from intubation), and use of inotropes and vasopressors are essential factors to consider when analysing the outcomes of patients receiving ECMO for COVID-19. Despite post-discharge survival being favourable, persisting long-term symptoms suggest that dedicated post-ECMO follow-up programmes are required. FUNDING: None.

Single-center experience of temporary-permanent pacemaker use in COVID-19 patients supported with veno-venous ECMO: A case series.

INTRODUCTION: In the first year of the COVID-19 pandemic, nine out of 129 patients (7%) developed life-threatening bradycardia episodes ultimately requiring a TPPM, whilst being supported with VV-ECMO for severe COVID-19 ARDS in our tertiary cardio-pulmonary failure center. ANALYSIS: All subjects had asystole due to sinus node dysfunction and experienced at least one episode involving cardiopulmonary resuscitation. Most bradycardic events were seen in the context of vagal hypersensitivity. Mean time from general ICU admission to TPPM insertion was 20.6 ± 8.9 days. One patient developed a large chest wall hematoma weeks after TPPM implantation, no other TPPM-related issues were observed. No patient required a long-term pacing system. Six-months survival rate was high (89%). CONCLUSION: These findings suggested that transient life-threatening sinus node disease is not uncommon in ECMO-dependent COVID-19 ARDS patients. TPPM with an active fixation lead is sometimes needed to facilitate ongoing ICU care, however, long-term permanent pacing was not required.

A comparison of long term outcomes in patients managed with VV-ECMO in the first and second waves of the COVID-19 pandemic in the UK (preprint)

Background: Early studies of veno-venous extracorporeal membrane oxygenation (VV-ECMO) in COVID-19 have revealed similar outcomes to historical cohorts. Changes in the disease and treatments has led to differences in the patients supported on VV-ECMO in the 1 st and 2 nd waves. We aimed to compare these two groups in both the acute and follow-up phase. Methods: In this retrospective study, we identified the differences between patients supported on ECMO for COVID-19 between wave 1 (17/03/2020-31/08/2020) and wave 2 (01/09/2020-25/05/2021). We examined mortality at censoring date (30/11/2021) and decannulation, patient characteristics, complications and lung function and quality of life (QOL – by EQ5D3L) at first follow-up. Findings: One-hundred and twenty-three patients were included in our analysis. Survival at censoring date [Chi-sqaured 6.35, p=0.012] and decannulation [90.4% vs 70.0%, p<0.001], was significantly lower in the 2 nd wave, whilst duration of ECMO run was longer [12.0(18.0-30.0) days vs. 29.5(15.5-58.3)] days (p=0.005)). Wave 2 patients had longer application of non-invasive ventilation (NIV) prior to ECMO and a higher incidence of barotrauma. Patient age and NIV use were independently associated with increased mortality [OR 1.07(1.01-1.14), p=0.025 and 3.37(1.12–12.60), p=0.043 respectively]. QOL and lung function, apart from KCOc was similar at follow up across the waves. Conclusion: Most patients with COVID-19 supported on ECMO in both waves survived in the short and longer term. At follow-up patients had similar lung function and QOL across the 2 waves. This suggests that ECMO has an ongoing role in the management of a carefully selected group of patients with COVID-19. Trial Registration Research Ethics Committee (20/EM/0204)

Survival benefit of extracorporeal membrane oxygenation in severe COVID-19: a multi-centre-matched cohort study.

PURPOSE: Extracorporeal membrane oxygenation (ECMO) has become an established therapy for severe respiratory failure in coronavirus disease 2019 (COVID-19). The added benefit of receiving ECMO in COVID-19 remains uncertain. The aim of this study is to analyse the impact of receiving ECMO at specialist centres on hospital mortality. METHODS: A multi-centre retrospective study was conducted in COVID-19 patients from 111 hospitals, referred to two specialist ECMO centres in the United Kingdom (UK) (March 2020 to February 2021). Detailed covariate data were contemporaneously curated from electronic referral systems. We analysed added benefit of ECMO treatment in specialist centres using propensity score matching techniques. RESULTS: 1363 patients, 243 receiving ECMO, were analysed. The best matching technique generated 209 matches, with a marginal odds ratio (OR) for mortality of 0.44 (95% CI 0.29-0.68, p < 0.001) and absolute mortality reduction of 18.2% (44% vs 25.8%, p < 0.001) for treatment with ECMO in a specialist centre. CONCLUSION: We found ECMO provided at specialist centres conferred significant survival benefit. Where resources and specialism allow, ECMO should be widely offered.

Impact of major bleeding and thrombosis on 180-day survival in patients with severe COVID-19 supported with veno-venous extracorporeal membrane oxygenation in the United Kingdom: a multicentre observational study.

Bleeding and thrombosis are major complications in patients supported with extracorporeal membrane oxygenation (ECMO). In this multicentre observational study of 152 consecutive patients (≥18 years) with severe COVID-19 supported by veno-venous (VV) ECMO in four UK commissioned centres during the first wave of the COVID-19 pandemic (1 March to 31 May 2020), we assessed the incidence of major bleeding and thrombosis and their association with 180-day mortality. Median age (range) was 47 years (23-65) and 75% were male. Overall, the 180-day survival was 70·4% (107/152). The rate of major bleeding was 30·9% (47/152), of which intracranial bleeding (ICH) was 34% (16/47). There were 96 thrombotic events (63·1%) consisting of venous 44·7% [68/152 of which 66·2% were pulmonary embolism (PE)], arterial 18·6% (13/152) and ECMO circuit thrombosis 9·9% (15/152). In multivariate analysis, only raised lactate dehydrogenase (LDH) at the initiation of VV ECMO was associated with an increased risk of thrombosis [hazard ratio (HR) 1·92, 95% CI 1·21-3·03]. Major bleeding and ICH were associated with 3·87-fold (95% CI 2·10-7·23) and 5·97-fold [95% confidence interval (CI) 2·36-15·04] increased risk of mortality and PE with a 2·00-fold (95% CI1·09-3·56) risk of mortality. This highlights the difficult balancing act often encountered when managing coagulopathy in COVID-19 patients supported with ECMO.

The Pulmonary Circulation and the Right Ventricle in ARDS

The acute respiratory distress syndrome (ARDS) is major clinical problem in respiratory medicine carrying a high mortality and morbidity burden. This review summarizes the diagnosis and pathophysiology behind pulmonary hypertension and right ventricular dysfunction in ARDS as well as current recommended treatment approaches.

Six Month Mortality in Patients with COVID-19 and Non-COVID-19 Viral Pneumonitis Managed with Veno-Venous Extracorporeal Membrane Oxygenation.

A significant proportion of patients with COVID-19 develop acute respiratory distress syndrome (ARDS) with high risk of death. The efficacy of veno-venous extracorporeal membrane oxygenation (VV-ECMO) for COVID-19 on longer-term outcomes, unlike in other viral pneumonias, is unknown. In this study, we aimed to compare the 6 month mortality of patients receiving VV-ECMO support for COVID-19 with a historical viral ARDS cohort. Fifty-three consecutive patients with COVID-19 ARDS admitted for VV-ECMO to the Royal Brompton Hospital between March 17, 2020 and May 30, 2020 were identified. Mortality, patient characteristics, complications, and ECMO parameters were then compared to a historical cohort of patients with non-COVID-19 viral pneumonia. At 6 months survival was significantly higher in the COVID-19 than in the non-COVID-19 viral pneumonia cohort (84.9% vs. 66.0%, p = 0.040). Patients with COVID-19 had an increased Murray score (3.50 vs. 3.25, p = 0.005), a decreased burden of organ dysfunction (sequential organ failure score score [8.76 vs. 10.42, p = 0.004]), an increased incidence of pulmonary embolism (69.8% vs. 24.5%, p < 0.001) and in those who survived to decannulation longer ECMO runs (19 vs. 11 days, p = 0.001). Our results suggest that survival in patients supported with EMCO for COVID-19 are at least as good as those treated for non-COVID-19 viral ARDS.

COVID-19 Pulmonary Failure and Extracorporeal Membrane Oxygenation: First Experience from Three European Extracorporeal Membrane Oxygenation Centers.

On April 17, 2020, a coronavirus disease 2019 (COVID-19) webinar was held by selected international experts in the field of intensive care and specialized respiratory ECMO centers from Germany, Italy, Spain, and the United Kingdom, which was hosted by the German Heart Centre Berlin/Charité. The experts shared their experience about the treatment of 42 patients with severe acute respiratory failure requiring venovenous extracorporeal membrane oxygenation (VV-ECMO). Patients were predominantly male (male-to-female ratio: 3:1), with a mean age of 51 years (range: 25-73 years). VV-ECMO support was indicated in 30% of the ventilated COVID-19 patients. The mean time requiring mechanical ventilation was 16.5 days, with a mean duration of ECMO support of 10.6 days. At the time of the webinar, a total of 17 patients had already been decannulated from ECMO, whereas six died with multiorgan failure. 18 patients remained on ECMO, with their final outcomes unknown at the time of the webinar. Hospital mortality was 25.6% (as of April 17, 2020). In this respect, VV-ECMO, provided by expert centers, is a recognized and validated mode of advanced life-support during the recent COVID-19 pandemic with good outcomes.

Pulmonary Angiopathy in Severe COVID-19: Physiologic, Imaging, and Hematologic Observations.

Rationale: Clinical and epidemiologic data in coronavirus disease (COVID-19) have accrued rapidly since the outbreak, but few address the underlying pathophysiology.Objectives: To ascertain the physiologic, hematologic, and imaging basis of lung injury in severe COVID-19 pneumonia.Methods: Clinical, physiologic, and laboratory data were collated. Radiologic (computed tomography (CT) pulmonary angiography [n = 39] and dual-energy CT [DECT, n = 20]) studies were evaluated: observers quantified CT patterns (including the extent of abnormal lung and the presence and extent of dilated peripheral vessels) and perfusion defects on DECT. Coagulation status was assessed using thromboelastography.Measurements and Results: In 39 consecutive patients (male:female, 32:7; mean age, 53 ± 10 yr [range, 29-79 yr]; Black and minority ethnic, n = 25 [64%]), there was a significant vascular perfusion abnormality and increased physiologic dead space (dynamic compliance, 33.7 ± 14.7 ml/cm H2O; Murray lung injury score, 3.14 ± 0.53; mean ventilatory ratios, 2.6 ± 0.8) with evidence of hypercoagulability and fibrinolytic "shutdown". The mean CT extent (±SD) of normally aerated lung, ground-glass opacification, and dense parenchymal opacification were 23.5 ± 16.7%, 36.3 ± 24.7%, and 42.7 ± 27.1%, respectively. Dilated peripheral vessels were present in 21/33 (63.6%) patients with at least two assessable lobes (including 10/21 [47.6%] with no evidence of acute pulmonary emboli). Perfusion defects on DECT (assessable in 18/20 [90%]) were present in all patients (wedge-shaped, n = 3; mottled, n = 9; mixed pattern, n = 6).Conclusions: Physiologic, hematologic, and imaging data show not only the presence of a hypercoagulable phenotype in severe COVID-19 pneumonia but also markedly impaired pulmonary perfusion likely caused by pulmonary angiopathy and thrombosis.

Respiratory management in severe acute respiratory syndrome coronavirus 2 infection.

The severe acute respiratory syndrome coronavirus 2 pandemic is to date affecting more than a million of patients and is challenging healthcare professionals around the world. Coronavirus disease 2019 may present with a wide range of clinical spectrum and severity, including severe interstitial pneumonia with high prevalence of hypoxic respiratory failure requiring intensive care admission. There has been increasing sharing experience regarding the patient's clinical features over the last weeks which has underlined the need for general guidance on treatment strategies. We summarise the evidence existing in the literature of oxygen and positive pressure treatments in patients at different stages of respiratory failure and over the course of the disease, including environment and ethical issues related to the ongoing coronavirus disease 2019 infection.