Noninvasive Ventilation of Patients with Acute Respiratory Distress Syndrome. Insights from the LUNG SAFE Study

TLDR

Noninvasive ventilation is increasingly used in ARDS, yet evidence supporting its use remains sparse. The study aimed to assess whether PaO₂/FiO₂‑based ARDS severity classification is useful during NIV and to describe current NIV practice and outcomes. Using the LUNG SAFE cohort, 2,813 ARDS patients were analyzed, of whom 436 (15.5 %) received NIV on days 1–2, and the study examined NIV use, severity classification, and clinical outcomes. PaO₂/FiO₂ severity predicted higher ventilatory support, NIV failure (22.2 % mild, 42.3 % moderate, 47.1 % severe), and ICU mortality, with hospital mortality 16.1 % versus 45.4 % for NIV success versus failure; NIV was independently linked to increased ICU mortality (HR 1.446) but not hospital mortality, and propensity‑matched analysis confirmed higher ICU mortality versus invasive ventilation when PaO₂/FiO₂ < 150 mm Hg, although NIV was used in 15 % of ARDS patients regardless of severity. The study is registered at ClinicalTrials.gov (NCT02010073).

Abstract

Noninvasive ventilation (NIV) is increasingly used in patients with acute respiratory distress syndrome (ARDS). The evidence supporting NIV use in patients with ARDS remains relatively sparse.To determine whether, during NIV, the categorization of ARDS severity based on the PaO2/FiO2 Berlin criteria is useful.The LUNG SAFE (Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure) study described the management of patients with ARDS. This substudy examines the current practice of NIV use in ARDS, the utility of the PaO2/FiO2 ratio in classifying patients receiving NIV, and the impact of NIV on outcome.Of 2,813 patients with ARDS, 436 (15.5%) were managed with NIV on Days 1 and 2 following fulfillment of diagnostic criteria. Classification of ARDS severity based on PaO2/FiO2 ratio was associated with an increase in intensity of ventilatory support, NIV failure, and intensive care unit (ICU) mortality. NIV failure occurred in 22.2% of mild, 42.3% of moderate, and 47.1% of patients with severe ARDS. Hospital mortality in patients with NIV success and failure was 16.1% and 45.4%, respectively. NIV use was independently associated with increased ICU (hazard ratio, 1.446 [95% confidence interval, 1.159-1.805]), but not hospital, mortality. In a propensity matched analysis, ICU mortality was higher in NIV than invasively ventilated patients with a PaO2/FiO2 lower than 150 mm Hg.NIV was used in 15% of patients with ARDS, irrespective of severity category. NIV seems to be associated with higher ICU mortality in patients with a PaO2/FiO2 lower than 150 mm Hg. Clinical trial registered with www.clinicaltrials.gov (NCT 02010073).