key: cord-0807639-reyeaas7
authors: Charlton, Matthew; Dashey, Susan; Stubbs, Abigail; Lai, Florence YL; Bird, Paul W; Badhwar, Vinay; Tang, Julian W
title: Comparing SARS-CoV-2 and influenza A(H1N1)pdm09-infected patients requiring ECMO – a single-centre, retrospective observational cohort experience
date: 2020-11-09
journal: J Infect
DOI: 10.1016/j.jinf.2020.11.003
sha: f324fb88399ae33be586930406a2323d3289b2bc
doc_id: 807639
cord_uid: reyeaas7

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We read with interest the recent report from Fiore and colleagues, 1 describing their experience with ECMO on COVID-19 cases. Here we share our own ECMO-COVID-19 experience, and compare this with our previous experience of ECMO use in influenza patients. 2 ECMO is a resource-intensive, highly specialised, and expensive form of life support with the potential for significant complications with unknown benefits, in the management of COVID-19.

Thus its clinical utility during the current pandemic has been uncertain. 3 An early retrospective case series from China described the role of ECMO in COVID-19 as 'unpromising', with nearly half of patients treated with ECMO dying from septic shock and multiple organ failure. 4 To investigate this further, we describe the clinical characteristics and outcomes of 34 patients presenting with severe COVID-19 pneumonitis who received respiratory ECMO support during the COVID-19 pandemic to one of the commissioned UK respiratory ECMO centres. Singlecentre, retrospective data collection was performed for all patients receiving respiratory ECMO support for severe respiratory failure secondary to SARS-CoV-2 infection during the peak of the UK pandemic (1 st April to 31 st May 2020). Various ECMO-related and laboratory parameters were extracted and statistically compared between patients who died (n=18) and those who survived (n=16) using the t-test or Mann-Whitney test for continuous variables and the Fisher-exact test for categorical variables. Correlation between duration on ECMO and laboratory parameters was assessed using Spearman's rank correlation coefficient.

A total of 268 patients were referred for consideration of respiratory ECMO support in Leicester (patient eligible criteria are shown in Figure S1 ). Of the 268 referrals, 38 were retrieved for consideration of ECMO. Thirty-four went on to receive ECMO support, with 4 patients managed with advanced conventional ventilatory support as part of the Severe Acute Respiratory Failure (SARF) pathway (Table S1).

The mean age of the 34 patients receiving ECMO support was 46 years (range: 28-58). The majority were male (27/34, 79%), with a mean body mass index (BMI) of 31.9 (range: 22.4-45), and most patients (88%) had at least one comorbidity (hypertension, diabetes or obesity).

The most frequently occurring COVID-19 symptoms in this patient group included fever (26/34, 76%), cough (25/34, 74%) and myalgia (10/34, 29%). Anosmia was a relatively uncommon finding, being recognised in only 2 patients (6%). Black and Minority Ethnic (BAME) groups accounted for 59% (20/34) of patients, with 38% (13/34) of the cohort being healthcare workers.

Co-morbid conditions were present in the majority of patients (30/34, 88%), with the most common being: obesity (23/34, 68%), hypertension (8/34, 24%) and diabetes (4/34, 12%). The majority of patients had a dual-lumen cannula configuration of the right internal jugular vein (28/34, 82%), as is routine practice for our unit. Renal replacement therapy was initiated in 26% (9/34) of patients. The mean duration of ventilation prior to initiation of ECMO was 4.9 days (range: 2-8), and the mean duration of ECMO support was 13.2 days (range: 4-26). The survival to discharge in this cohort of patients was 53% (18/34). White cell count also appears significantly lower in the influenza cohort (5. In this single-site, retrospective observational cohort study, we present the data from 34 patients admitted to one of the six UK severe respiratory failure centres who received ECMO support for COVID-19 pneumonitis. Earlier speculation by some teams about the potential application of ECMO suggested that it may be useful in severe cases of COVID-19, though this would depend very much on case selection. This speculation has since been borne out by more recent reports on single 5,6 , small 7 and larger 8, 9 case series of patients with severe COVID-19, where the authors have been cautious about the potential benefits of ECMO in such patients, emphasising the limited capacity for this complex treatment.

A recent ECMO consensus document 10 states this succinctly as: "ECMO is a highly technical therapy and is resource intensive. Although the distribution of this therapy should be as equitable as possible, during a pandemic such as COVID-19, distribution should focus on optimal candidates for recovery."

In our case series presented here, it is difficult to conclude exactly how much the ECMO therapy contributed to the survival of these severely ill COVID-19 patients versus if they only had standard intensive care unit (ICU) support, as it was not possible for each patient to act as his/her own control in this comparison. However, as per our previous experience reported on seasonal influenza patients requiring ECMO 2 it is likely that ECMO was more beneficial than not in this highly selected patient cohort. 

White cell count ( 

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Preparing for the Most Critically Ill Patients With COVID-19: The Potential Role of Extracorporeal Membrane Oxygenation

Prognosis when using extracorporeal membrane oxygenation (ECMO) for critically ill COVID-19 patients in China: a retrospective case series

Successful treatment of COVID-19 using extracorporeal membrane oxygenation, a case report

Large intracardiac thrombus in a COVID-19 patient treated with prolonged extracorporeal membrane oxygenation implantation

Extracorporeal Membrane Oxygenation in Coronavirus Disease 2019-associated Acute Respiratory Distress Syndrome: An Initial US Experience at a High-volume Centre

Extracorporeal Membrane Oxygenation for Patients With COVID-19 in Severe Respiratory Failure

Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome associated with COVID-19: a retrospective cohort study

Extracorporeal Life Support Organization Coronavirus Disease 2019 Interim Guidelines: A Consensus Document from an International Group of

Interdisciplinary Extracorporeal Membrane Oxygenation Providers