Aerosol therapy delivers medicines as a fine mist directly into the lungs. This allows faster action and fewer whole-body side effects. It is a key treatment for diseases such as asthma and COPD. In acute respiratory distress syndrome (ARDS), early laboratory and small clinical studies suggested that inhaled beta-2 agonists and corticosteroids might help the lungs heal by improving mucus clearance, reducing inflammation, and helping remove excess fluid. However, larger randomized trials have not shown clear clinical benefits. Therefore, major guidelines do not provide specific recommendations for aerosol use in ARDS. There are also safety concerns, including risks of low potassium levels, abnormal heart rhythms, worsening lung function, and increased healthcare costs. Despite these uncertainties, our previous study showed that aerosol therapy continues to be used widely in ARDS patients. However, that study was small and limited to one country, so the findings may not apply to other regions.

To address this gap, we have designed Aero-in-ARDS, a large, multi-national, prospective observational study. This study will investigate how often aerosol therapy is used in ARDS, what types of aerosol drugs are given, and how practices differ across countries. By identifying current patterns and comparing them with existing evidence, the study aims to highlight gaps in knowledge and guide future research.

This prospective, multi-center, international cohort observational study will be conducted upon approval from the Institutional Ethics Committee (IEC). Centers' recruitment from various parts of the Globe will be done on an invitation basis. Participation in centers will be purely voluntary. As per their local policy, the participating center will take additional IEC approval or waiver at their center to initiate enrollment. Requests for patients' or legal representatives' informed consent will be made in accordance with national law.

The study protocol is designed and will be reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement. All consecutive eligible patients with ARDS admitted to participating ICUs will be enrolled. The study aims to include all consecutive eligible patients to ensure accurate and representative data collection. Each Participating center will screen all consecutive ARDS patients requiring invasive mechanical ventilation during the study's six-month inclusion period, or a maximum of 25 patients per center. Patients who met the inclusion/exclusion criteria will be followed for the next 14 days or till ICU discharge/death or weaning from IMV, whichever comes first.

Inclusion Criteria: all newly admitted adult patients with a diagnosis of ARDS in the participating ICU

1. The patient requires mechanical ventilation.
2. Age ≥ 18 years
3. Informed consent (if required)

Exclusion Criteria:

1. Age <18 years
2. Patients managed with NIV, and HFNO

Each Participating center will screen all consecutive ARDS patients requiring invasive mechanical ventilation during the study's six-month inclusion period, or a maximum of 25 patients per center. Patients who met the inclusion/exclusion criteria will be followed for the next 14 days or till ICU discharge/death or weaning from IMV, whichever comes first.

Access to STUDY IPD can be requested by qualified researchers engaging in independent scientific research, and will be provided following review and approval of a research proposal and Statistical Analysis Plan and execution of a Data Sharing Agreement.

6 months after publication of manuscript and the data will be made accessible for up to 24 months

qualified researchers engaging in independent scientific research