Nutritional Intake in Patients on Noninvasive Ventilation: a Prospective Observational Study

The primary objective is to quantify the caloric and protein intake in adult participants with acute respiratory failure who start a noninvasive ventilation treatment. The main question is: \- Are participants meeting their caloric and protein target during noninvasive ventilation treatment? Participants will complete a five-day food diary collection starting from the initiation of noninvasive ventilation treatment.

Inclusion Criteria: * Age of 18 years or more * Hospitalization in the participant ordinary wards, intermediate care units and intensive care unit at the Maggiore della Carità University Hospital, Novara, Italy * Admission for acute respiratory failure of any cause requiring noninvasive ventilation treatment within 24 hours from hospital admission Exclusion Criteria: * Palliative noninvasive ventilation treatment * Contraindication to oral nutrition from hospital admission * Patients admitted for surgical or gastroenterological diagnosis * Severe immunocompromised patients or patients undergoing therapies contraindicating oral nutrition