Dénutrition de l'insuffisant respiratoire chronique : physiopathologie et prise en charge

Denutrition is common in end-stage respiratory insufficiency. It is correlated with a poor prognosis. It is due to an unbalance between increased energy demand and decreased oral supply. Pathophysiology of denutrition differs according to aetiology of chronic respiratory insufficiency. In patients with chronic obstructive pulmonary disease, it is well accepted that the high cost of work of breathing is the main explanation of the increased energy expenditure. In such situations, these patients do not eat enough nutrients and hence, may be considered for oral supplementation or enteral nutrition. However, some of them do not respond to this treatment, because cachexia may be the expression of the metabolic adaptation to chronic hypoxia. In other diseases, such as neurological disorders where difficulties of swallowing are involved, enteral nutrition via a gastrostomy is recommended. This support is also efficient in cystic fibrosis in which the intestinal absorption is impaired, mostly as a consequence of pancreatic insufficiency.