Therapeutic effects of artificial nutrition in intensive care patients: New insights

Nutritional support has become a routine part of the care of critically ill patients and it is now widely accepted for the treatment and prevention of malnutrition and related complications. Most positive effects of artificial nutrition on the outcome of the critically ill patient result from controlling complex physiologic changes that lead to catabolism and loss of body cell mass. The knowledge of metabolic requirements is essential to define an appropriate artificial nutritional regimen, according to guideline recommendations. There is a general agreement that enteral nutrition (EN) is better than parenteral since it is safer, preserves gut function and is more cost effective. Most comparative studies of EN and PN, however, show that outcomes are comparable with either route. Evidence supports early initiation of nutrition support and debate is ongoing over whether gastric feedings or small-bowel feedings are best. Immunonutrition refers to the potential to modulate the activity of the immune system by interventions with specific nutrients (arginine, glutamine, n-3 fatty acids, antioxidants agents) and thereby to attempt to further improve the clinical outcome of selected critically ill patients. The emerging discipline of nutrigenomics (speculative branch of genes-nutrition interaction) has tremendous potential to change the future of our knowledge and intervention strategies on artificial nutrition.