Extracorporeal Membrane Oxygenation for COVID-19–associated Severe Acute Respiratory Distress Syndrome in Chile: A Nationwide Incidence and Cohort Study

Abstract

At a Glance Commentary Scientific Knowledge on the SubjectExtracorporeal membrane oxygenation (ECMO) has been incorporated in the World Health Organization recommendations for the management of COVID-19-associated severe acute respiratory distress syndrome (ARDS). However, the incidence of ECMO use, its time course and outcomes are unknown at a nationwide level under the COVID-19 pandemic scenario. What This Study Adds to the FieldIn this nationwide study, all patients who received ECMO for severe ARDS during the first wave of COVID-19 pandemic in Chile were identified. The incidence and time course of ECMO use was similar to that observed in the 2009 influenza A(H1N1) pandemic in Australia/New Zealand.The mortality rate was comparable to that reported for other indications of extracorporeal respiratory support. The operation of a National Advisory Commission for Adult ECMO was key to assist patient eligibility, transportation and allocation in tertiary centers in a resource-limited and logistically complex pandemic scenario. These findings might be useful for future COVID-19 pandemic waves worldwide. Total word count: 3475Funding: This investigation had no funding or grant.

Extracorporeal Membrane Oxygenation for COVID 2019-Acute Respiratory Distress Syndrome: Comparison between First and Second Waves (Stage 2)

“…As already discussed previously, age is a well-established risk factor for worse outcomes. Comorbidities were not different between the two wave groups and similar to other large cohort studies [ 20 , 33 , 34 , 35 , 36 , 38 ]. Otherwise, the patients during the second wave were prone to manifest higher severity of pulmonary involvement even if they had less extra-pulmonary organ dysfunction.…”

“…Another factor, contributing to the higher mortality rates in our cohort, may be the median SAPSII (58 (34–67)) higher than the ones reported by Schmidt et al [ 35 ] (median 45 (29–56)) and by Lebreton et al (median 40 (31–56)) [ 34 ]. Although not characterized to COVID-19 ARDS, the RESP score [ 32 ] reported by Schmidt et al [ 35 ] was 4 (2–5) and 3 (1–5) by Diaz et al [ 33 ], which is significantly higher than in our cohort with a median of −3 (−6,−1) and an estimated survival probability of 33%. The overall 90-day mortality rate of COVID-19 ICU patients was 116/502 (23.1%) in the whole cohort of our study with no significant statistical difference between the two waves (22% vs. 24%) regarding ICU mortality rates by age.…”

“…Although not characterized to COVID-19 ARDS, the RESP score [32] reported by Schmidt et al [35] was 4 (2-5) and 3 (1-5) by Diaz et al [33], which is significantly higher than in our cohort with a median of −3 (−6,−1) and an estimated survival probability of 33%. The overall 90-day mortality rate of COVID-19 ICU patients was 116/502 (23.1%) in the whole cohort of our study with no significant statistical difference between the two waves (22% vs. 24%) regarding ICU mortality rates by age.…”

“…The overall 90-day mortality rate of CARDS patients on V-V ECMO in our study was 32/50 (64%). Data from high-volume centers with retrospective design show that ECMO therapy was associated with a lower in-hospital mortality rate ranging from 36 to 54% [ 33 , 34 , 35 ]. Data from the international ELSO Registry captures a 52.4% in-hospital mortality in 1531 treated patients as of September 14th 2020 [ 36 ].…”

Appraising the Real-Life Need for Extracorporeal Membrane Oxygenation during the COVID-19 Pandemic

“…In this issue of the Journal, Diaz and colleagues (pp. 34–43 ) report the results of a population-based study focusing on patients with COVID-19–related ARDS treated with ECMO during the first wave of the pandemic in Chile ( 8 ). This is indeed the first cohort study evaluating the need for ECMO in COVID-19–related ARDS at a national level, in a country that has developed a coordinated national ECMO program ( 9 , 10 ), using data from comprehensive national databases of mechanically ventilated and ECMO-treated patients.…”