Exploring the Correlations of Lung Ultrasound with Delirium and Outcomes in Acute GEriatrics World: a Multicenter, Prospective, Observational Study from the GRETA Group of the Italian Society of Gerontology and Geriatrics

Inclusion Criteria: * Patients aged 65 years or older, admitted directly from the Emergency Room or Emergency Medical Services with acute respiratory symptoms or signs. Presence of acute respiratory symptoms, including: * Dyspnea or cough. * Oxygen saturation less than 94% or respiratory rate ≥ 22 breaths per minute, or PaO2/FiO2 \< 300. * Clinical suspicion of acute respiratory illness (e.g., pneumonia, acute congestive heart failure, pulmonary edema, COPD, pleural effusion, pneumothorax). * Lung ultrasound (LUS) performed within 48 hours of admission for clinical reasons. * Signed informed consent for participation in the study. Exclusion Criteria: * Presence of delirium upon admission. * Refusal to sign the informed consent form or consent to data collection. * Terminal illness with an estimated survival prognosis of no more than 3 months. * Previous open thoracic or cardiothoracic surgery compromising the quality of LUS images. * Lack of cooperation during the LUS examination. * Any condition determined by the investigators that could introduce bias into the study or compromise the quality of the LUS examination.