Adequate nutrition plays an important role in maintaining optimal health. The consequences of malnutrition have been well documented and contribute significantly to morbidity and mortality. Malnutrition increases health care costs by prolonging hospital length of stay due to the increased probability of medical complications which result from compromised immune function and impaired wound healing.
In general, malnutrition may be envisioned as a continuum with four basic stages. Initially, decreases in nutrient intake (e.g. poor diet, eating difficulty) or excessive losses (e.g. chronic diarrhea, abnormal bleeding, large draining wounds) limit nutrient availability. Next, nutrient stores are depleted as nutrients are required to meet metabolic demands. In the third stage, metabolic or biochemical changes occur, leading to marginal malnutrition. These are followed by deficiency symptoms. In this last stage, referred to as clinical or symptomatic malnutrition, cell or tissue damage is present and nutrient deficiencies are manifest by specific, observable symptoms. Malnutrition that results in the depletion of body cell mass and impaired function frequently accompanies acute and chronic diseases, as well as trauma. Perhaps as many as 40 to 50 percent of hospitalized medical or surgical patients either have or are at risk for developing malnutrition, with 5 to 10 percent of patients classified as severely malnourished.
This manual is not intended to be a comprehensive textbook on nutrition but rather is intended to provide guidelines for the evaluation and management of patients with exceptional nutritional requirements. The goal of this resource manual is to maximize patient benefits from parenteral or enteral nutrition therapy while minimizing potential complications.