Related Experiment Video
Updated: Apr 3, 2026
Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome ARDS
Published on: April 7, 2021
Defining the Resolution of Acute Respiratory Distress Syndrome: A Delphi Consensus Study
Timothy E Weir1,2,3, Eddy Fan1,2,3,4,5,6, Ewan C Goligher1,2,4,5,6
1Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
Objectives:
There are no established criteria to define the resolution of acute respiratory distress syndrome (ARDS). We aimed to develop an expert consensus definition of ARDS resolution.
Design:
Modified Delphi consensus study with three iterative rounds.
Setting:
Electronic surveys.
Subjects:
A panel of 19 ARDS experts participated in the Delphi process. Experts were identified using prespecified criteria.
Interventions:
The Delphi process was conducted over three rounds. Item generation was performed in round 1 with all panelists invited to suggest defining characteristics for resolution of ARDS with corresponding operational definitions, which were then voted on by the panel. Item refinement in rounds 2 and 3. Thresholds for agreement were specified a priori and set at 70%.
Measurements And Main Results:
Nineteen panelists submitted complete responses to the first round with 16 panelists contributing to the final definition that met a priori consensus criteria after the third round questionnaire. The panel agreed on the following elements: 1) resolution of hypoxemia, defined as ratio of Pa o2 /F io2 greater than 300 (or ratio of oxygen saturation to F io2 > 315) for more than 24 hours and 2) normalization of level of respiratory support, defined as "if still intubated, this is for primarily nonrespiratory reasons (e.g. altered mental state, ICU-acquired weakness) and ventilatory assistance is minimal (i.e., positive end-expiratory pressure less than or equal to 5 cm H 2 O, and no adjunctive interventions); if maximal respiratory support was continuous positive airway pressure (CPAP) or noninvasive ventilation (NIV), then no longer requiring CPAP or NIV; if maximal respiratory support was oxygen via high-flow nasal cannula (HFNC), then no longer requiring HFNC; and if maximal respiratory support was standard oxygen, then longer receiving oxygen."
Conclusions:
A high level of consensus was achieved on criteria defining the resolution of ARDS. Future work is required to explore the epidemiology and performance characteristics of this definition.
Related Concept Videos
01:29Acute Respiratory Failure-V
Ensure that patients are monitored continuously for their response to therapy, including changes in...
01:23Acute Respiratory Failure-IV
01:30Acute Respiratory Failure-III
01:21Acute Respiratory Failure-II
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
01:21Acute Respiratory Failure-I
Definition: It is defined by specific criteria based on blood gas measurements. Hypoxemia happens when the partial pressure of oxygen (PaO2) falls below 60 mmHg. At the same time,...
01:26Endoscopic Studies II: Thoracocentesis
Description
Excess pleural fluid or air may accumulate in some respiratory disorders in the thoracic cavity. To treat pleural effusion, a physician conducts thoracentesis by carefully piercing the chest wall and entering...