ECMO without a tube: the failures cluster in the first ten days

Design

international retrospective cohort study, 14 centres in 8 countries, 2015-2024, multivariate analysis

Population

307 adults with ARDS managed on ECMO without invasive ventilation: 113 primary awake ECMO, 194 extubated on ECMO

Primary outcome

mortality 90 days after ECMO initiation

Effect

90-day mortality 30.1% (primary awake) vs 14.9% (extubated); strategy failure 40.7% vs 24.2%; failure associated with death (HR 5.95, 95% CI 2.63-13.46 and HR 7.67, 3.44-17.11)

An international retrospective cohort across 14 centres in eight countries collected 307 adults with acute respiratory distress syndrome managed on extracorporeal membrane oxygenation without invasive ventilation between 2015 and 2024 — 113 cannulated to avoid intubation altogether (primary awake ECMO) and 194 extubated while on support.

Ninety-day mortality was 30.1% in the primary awake group and 14.9% in the extubated group. Strategy failure — needing intubation or reintubation — occurred in 46 (40.7%) and 47 (24.2%) respectively, mostly within the first ten days. Failure was strongly associated with death in both groups (HR 7.67, 95% CI 3.44-17.11 in extubated; HR 5.95, 2.63-13.46 in primary awake). Older age predicted death in the extubated group, and a longer interval from ICU admission to cannulation in the primary awake group. The commonest reason for failure was worsening respiratory failure, then agitation or delirium in the awake group and inability to clear secretions in the extubated group.

The two groups are not comparable and the authors do not pretend otherwise — patients selected for each are different, and the mortality gap reflects that. What transfers is the failure analysis: four in ten primary awake attempts did not hold, failure carried a five- to eightfold mortality hazard, and the modifiable contributors were sedation-related agitation and secretion clearance rather than anything about the circuit.

• Plan for a 40% failure rate when attempting primary awake ECMO, and define in advance what triggers intubation
• Concentrate monitoring in the first ten days; that is when failure happens
• Agitation and delirium are a leading cause of failure — get the sedation and delirium plan right before cannulation
• In extubated ECMO the limiting factor is secretion clearance; assess cough strength before extubating
• Time from ICU admission to cannulation predicted death in the awake group — deciding late is itself a risk

Why it matters

It puts a number on how often an awake ECMO attempt does not hold, and names the two modifiable reasons.

Don't overread it

Retrospective, no control group, and two self-selected populations — this cannot say whether avoiding ventilation helped anyone.

The statistics, in plain English

Hazard ratios of 5.95 and 7.67 for strategy failure describe an association, and much of it is confounded by the reason for failure — patients whose respiratory failure worsened were always going to do worse. The 30.1% versus 14.9% mortality difference between the two strategies is not a comparison of strategies at all: the patients selected for each were different from the start.

Read the rest in the app

You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.

Get Daily Doctor — free

Scan to keep reading on your phone. No account needed to start.