الفهرس 
Nutritional Status in Critically ill PatientsOnly 14 pages are availabe for public view
 |  | from | 16 |  |  |
| | | from | 16 | | |
Abstract
The intensive care unit (ICU) patient presents a number of nutritional challenges. The case mix of patients admitted to ICUs may range from those admitted electively after major elective surgery to those admitted as emergencies after some surgical catastrophe, major trauma, sepsis, or respiratory failure. The variation in age range and prior health status may be extreme and nowadays ICUs are admitting increasingly more elderly, frail, or malnourished patients whose nutritional reserve may be severely compromised.
Critically ill patients requiring vital organ support in ICU commonly have anorexia and may be unable to feed volitionally by mouth for periods ranging from days to months. Unless such patients are provided with macronutrients in the form of enteral or parenteral nutrition, they accumulate an energy deficit that rapidly reaches proportions that contribute to lean-tissue wasting and that are associated with adverse outcomes.
Nutritional support has gained importance with better understanding of the pathophysiology of protein energy malnutrition (PEM) in ICU patients and optimal modalities in administration of nutritional therapy.
The degree of energy deficit accumulating in critically ill patients is strongly associated with the duration of stay in the ICU, which, in turn, is associated with an increased incidence of infectious complications and risk of death.
The objectives of nutritional support till recently were limited to preserving lean body mass, maintaining immune function, and averting metabolic complications. Nutrition support is now more focused on attenuating the metabolic response to stress, preventing oxidative cellular injury, and modulating the immune response. Nutritional modulation of the stress response includes early enteral nutrition, appropriate macro and micronutrient delivery, and meticulous glycemic control.
It is now firmly established that the enteral route is the preferred for nutritional support. Parenteral nutrition is indicated only when enteral nutrition is ”contraindicated” (short gut syndromes, proximal high output fistula, perforated bowel, bowel obstruction, severe gastrointestinal bleed, and severe hemodynamic instability). Recommendations for initiation of parenteral therapy in patients, where enteral nutrition is contraindicated, vary from 3-7 days amongst different various guidelines.
Undernutrition is consistently common among ICU patients around the world even today. There is a need to emphasize that nutritional support of critically ill is a primary therapeutic strategy.