Nutrition in critically ill patients after intensive care unit (ICU) discharge is frequently omitted and still poorly investigated. Patients during ICU stay experience great muscle loss that is the main cause of ICU-acquired weakness with consequent physical disability, including difficult eating. Moreover, ICU survivors have an altered nutritional status, may present dysphagia, taste alterations and mood disorders which in turn could aggravate malnutrition. For this purpose, body composition should be determined in critically ill patients not only during ICU stay, but also after discharge to the rehabilitation units where muscle mass could be restored with adequate nutrition and exercise. Recent advances highlight how a personalized nutrition could optimize nutritional status in critically ill patients. Bioimpedance analysis is a useful tool to determine body composition in post-ICU period, determining lean body mass, which is the effective part of body weight metabolically active. Moreover, it could allow for a suitable protein dosage prescription optimized on lean body mass of the patient and not on a fixed amount calculated on generic formula based on body weight.
