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Updated: Nov 15, 2025

Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome ARDS
Published on: April 7, 2021
Spontaneous Versus Controlled Mechanical Ventilation in Patients with Acute Respiratory Distress Syndrome
Tayyba Naz Aslam1,2, Thomas Lass Klitgaard3,4, Kristin Hofsø2,5
1Department of Anaesthesiology, Division of Emergencies and Critical Care, Rikshospitalet Medical Centre, Oslo University Hospital, P.O.Box 4950, Nydalen, Oslo, Norway.
Purpose Of Review:
To review clinical evidence on whether or not to allow mechanically ventilated patients with acute respiratory distress syndrome (ARDS) to breathe spontaneously.
Recent Findings:
Observational data (LUNG SAFE study) indicate that mechanical ventilation allowing for spontaneous breathing (SB) is associated with more ventilator-free days and a shorter stay in the intensive care unit without any effect on hospital mortality. A paediatric trial, comparing airway pressure release ventilation (APRV) and low-tidal volume ventilation, showed an increase in mortality in the APRV group. Conversely, in an unpublished trial comparing SB and controlled ventilation (NCT01862016), the authors concluded that SB is feasible but did not improve outcomes in ARDS patients.
Summary:
A paucity of clinical trial data continues to prevent firm guidance on if or when to allow SB during mechanical ventilation in patients with ARDS. No published large randomised controlled trial exists to inform practice about the benefits and harms of either mode.
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