[Nutritional support in the critically ill patient: to whom, how, and when?]

Existing data about indication and time of onset of nutritional support are not homogeneous. However, the presence of a deterioration of the nutritional status is accompanied by harmful effects so that, broadly speaking, specialized nutritional support onset would be advisable if a fasting period longer than 5-7 days is foreseen. Parenteral nutrition routinely administered to critically ill patients may increase their morbidity and mortality. Whenever possible, enteral nutrition should be the preferred route of nutrients intake since it has been shown to have a favorable effect on infectious complications rates. Enteral nutrition should be started early on (within the first 36 hours of admission). Although transpyloric nutrients administration may however reduce bronchoaspiration and increase the diet effective volume received by patients, there are no data for recommending routinary usage of the transpyloric route for nutritional support in the critically ill patients.