Brachial Plexus Injury After Prone Positioning

The goal of this prospective observational study is to estimate the prevalence of brachial plexus injury after prone positioning in patients with ARDS and to evaluate the safety of swimmer position. The main questions it aims to answer are: * Could arm positioning during pronation play a role in the development of any nerve injury at the brachial plexus level? * Is swimmer position safe when adopted during prone positioning? Participants will be studied at selective time points using EMG assessment.

Inclusion Criteria: * Age ≥ 18 years old * Admission to ICU for severe ARDS * Administration of sedation and neuromuscular blocking agents * Presence of endotracheal intubation and mechanical ventilation * Use of prone positioning to treat hypoxemia Exclusion Criteria: * Extracorporeal membrane oxygenation * Prone positioning performed in other centers * Prone positioning contraindications * Neurodegenerative disorders * Previous known brachial plexus injury