Enteral Versus Parenteral Feeding: The Avoidance of Systemic Infection in the Critically Ill

The critically ill patient very often presents with systemic evidence of infection including tachypnea, tachycardia and hypo-hyperthermia; this may lead to sepsis syndrome and subsequent multisystem organ failure. In order to manage this clinical condition, nutritional supportive therapy is very often required. The choice between enteral and parenteral nutrition is not always straightforward. Early enteral nutrition seems to exert beneficial effects, although parenteral nutrition is often easier to administer, and thus is the treatment of choice. There are only few prospective, randomized, controlled trials comparing the two methods of intervention therapy. Parenteral nutrition seems to be associated with mechanical, metabolic and septic complications, while enteral nutrition, which is associated with similar complications, prevents gastrointestinal mucosal atrophy, attenuates the injury stress response, maintains immunocompetence, and preserves normal gut flora. This literature review focuses on the role played by these two methods of nutritional support therapy in the development of systemic infections. This review will also analyze possible mechanisms of action and future therapeutic strategies.