A New Global Definition of Acute Respiratory Distress Syndrome.

BACKGROUND: Since the 2012 Berlin Definition of the Acute Respiratory Distress Syndrome (ARDS), several developments have supported the need for an expansion of the definition, including the use of high flow nasal oxygen (HFNO), expanding use of pulse oximetry in place of arterial blood gases, use of ultrasound for chest imaging, and the need for applicability in resource-limited settings.

METHODS: A Consensus Conference of 32 critical care ARDS experts was convened, had six virtual meetings (June 2021-March 2022), and subsequently obtained input from members of several critical care societies. The goal was to develop a definition that would: (1) identify patients with the currently accepted conceptual framework for ARDS; (2) facilitate rapid ARDS diagnosis for clinical care and research; (3) be applicable in resource-limited settings; (4) be useful for testing specific therapies; and (5) be practical for communication to patients and caregivers.

RESULTS: The committee made four main recommendations: (1) Include HFNO with a minimum flow rate of ≥ 30 liters/min; (2) Use arterial oxygen tension (PaO2 )/FiO2 ≤ 300 mmHg or SpO2 )/FiO2 < 315 (if SpO2 ≤ 97%) to identify hypoxemia; (3) Retain bilateral opacities for imaging criteria but add ultrasound as an imaging modality, especially in resource-limited areas; and (4) In resource-limited settings, do not require PEEP, oxygen flow rate, or specific respiratory support devices.

CONCLUSIONS: We propose a New Global Definition of ARDS that builds on the Berlin Definition. The recommendations also identify areas for future research, including the need for prospective assessments of feasibility, reliability, and prognostic validity of the proposed Global Definition. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (https://creativecommons.org/licenses/by-nc-nd/4.0/).