A New Global Definition of Acute Respiratory Distress Syndrome

Abstract

Background: Since publication of the 2012 Berlin definition of 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, the expansion of the use of pulse oximetry in place of arterial blood gases, the 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 to 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 high-flow nasal oxygen with a minimum flow rate of >30 L/min; 2) use Pa O 2 :FI O 2 < 300 mm Hg or oxygen saturation as measured by pulse oximetry Sp O 2 :FI O 2 < 315 (if oxygen saturation as measured by pulse oximetry is <97%) to identify hypoxemia; 3) retain bilateral opacities for imaging criteria but add ultrasound as an imaging modality, especially in resourcelimited areas; and 4) in resource-limited settings, do not require positive end-expiratory pressure, 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 the feasibility, reliability, and prognostic validity of the proposed global definition.

The Predictive Validity of the Berlin Definition of Acute Respiratory Distress Syndrome for Patients With COVID-19-Related Respiratory Failure Treated With High-Flow Nasal Oxygen: A Multicenter, Prospective Cohort Study*

“…Moreover, patients with greater illness severity as assessed by the Berlin definition may also be better identified for specific pharmacological and nonpharmacological interventions. Additionally, the extension of the Berlin definition to include HFNO-treated patients may expand the pool of eligible patients for inclusion in epidemiologic studies or clinical trials (10).…”

“…A recent consensus proposed a new “Global Definition” of ARDS broadening the criteria, proposing that intubation is not required to establish the diagnosis and that patients requiring HFNO greater than 30 liters per minute could be included (10). However, the authors recognized that “the recommendations identify areas for future research, including prospective assessments of feasibility, reliability, and prognostic validity categories of ARDS Global Definition”.…”

Globalize the Definition, Localize the Treatment: Increasing Equity and Embracing Heterogeneity on the Road to Precision Medicine for Acute Respiratory Distress Syndrome*

“…Acknowledging limitations of the Berlin definition, updated clinical criteria for ARDS were recently proposed by a group of international experts ( Table 1 ) (13). Retaining core components of the ARDS conceptual model that the Berlin definition seeks to capture, this “global” definition would, in line with the Kigali modification, allow for use of Sp o 2 /F io 2 ratio and lung ultrasound and include patients treated with HFNO.…”

“…For translational research and clinical trials, the advantages of an expanded ARDS definition are not restricted to LMICs. Systematically capturing patients in the early phases of acute lung injury may identify biological mechanisms associated with differential trajectories of pulmonary and extrapulmonary organ dysfunction (13, 18). Targeting treatable traits along the temporal spectrum of illness may interrupt time-sensitive mechanisms of multiple organ dysfunction, death, and disability attributable to ARDS.…”

“…Targeting treatable traits along the temporal spectrum of illness may interrupt time-sensitive mechanisms of multiple organ dysfunction, death, and disability attributable to ARDS. For patients receiving IMV or extracorporeal life support, the newly proposed definition maintains existing ARDS severity strata, ensuring that corresponding evidence-based treatment strategies and research efforts remain relevant (13).…”