Recent Advances in Nutritional Support in Mechanically Ventilated Critically Ill Patients

Abstract

Nutrition is an important aspect of patient care in acute or chronic critical illness. Appropriate nutritional support during the acute phase of critical illness has the potential to reserve or mitigate adverse consequences of poor nutritional status. An increasing nutritional deficit during a long ICU stay is associated with increased morbidity (infection rate, wound healing, mechanical ventilation, length of stay, duration of recovery and costs). Early nutritional support, provided within 24 hours of injury or intensive care unit (ICU) admission, is a key component in the treatment of critically ill patients and may reduce mortality by 8% to 13%. The nutritional state of hospitalized patients reflects directly on their clinical course, even that there are greater rate of hospital-acquired diseases and greater risk of clinical complications among malnourished patients, increasing the hospital length of stay (LOS) and reducing quality of life. This leads to high hospital costs because these patients have a greater need for intensive care or specialized services. Medical and surgical ill patients are subjected to stress, infection and impaired organ function, resulting in a hypercatabolic state, leading to metabolic derangement and malnutrition. The incidence of malnutrition worsens overtime in patients who require prolonged hospitalization. Critically ill patients are characterized by a number of alterations in carbohydrate, lipid, amino acid, protein and electrolytes metabolism. It was recognized that ICU patients are unique with varying nutritional requirements during their stay and understanding the issues involved such as tight glycemic control, the effects of over- and underfeeding will ultimately lead to a reduction in morbidity and mortality. The nutritional status of a critically ill patient depends on a part on the nutritional therapy given during acute critical illness and the primary function of the nutritional assessment is to identify pre-existing malnutrition in order to prevent or minimize further loss of body weight, particularly of cell mass, composition and function.