الفهرس 
NUTRITIONAL ASSESSMENTOnly 14 pages are availabe for public view
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Abstract
Malnutrition was defined as ‘‘a subacute or chronic state of nutrition in which a combination of varying degrees of over- or undernutrition and inflammatory activity has led to a change in body composition and diminished function’’. Its operationalization led to four elements that may serve as the basis of nutritional assessment: (1) measurement of nutrient balance, (2) measurement of body composition, (3) measurement of inflammatory activity, and (4) measurement of muscle, immune and cognitive function. Values obtained in people considered to be at nutritional risk should be related to outcome
Since, malnutrition is associated with increased morbidity and mortality, prevention or correction of nutrient depletion has the potential to minimize malnutrition-related complications. The goals of nutritional assessment are to identify patients who have, or are at risk of developing protein energy malnutrition, and to treat them and then monitor the adequacy of nutrition therapy.
Surgical patient populations at risk include patients with:
cancer receiving chemotherapy
major trauma, burn injuries or both
inflammatory bowel disease
chronic renal failure
fever, sepsis, or both
Healing from surgery is complex, and many factors, including nutritional status, can affect the outcome. A proper diet is essential for healing. Beginning before surgery and continuing throughout the healing process, you may require extra calories, protein, vitamins, and minerals, as well as adequate fluids to help maintain hydration to support circulation of nutrients.
Surgical diagnoses and procedures associated with an increased need for nutritional support include the following:
Necrotizing enterocolitis
Perforating appendicitis
Bowel resection
Enteral Nutritional Support
The enteral route is safer and cheaper and is therefore preferred whenever nutritional support is required, if the GI tract is functional. This does not mean that the gut has to be completely healthy. For example, elemental formulas may work well in cases with distal enterocutaneous or colocutaneous fistulas.
Some type of feeding tube is usually required. For short-term support, as long as several weeks, a nasogastric tube may suffice. A nasoduodenal or nasojejunal tube may be helpful in the presence of gastroesophageal reflux. However, all esophageal tubes tend to cause gastroesophageal reflux and esophagitis; thus, for long-term use, a feeding gastrostomy or jejunostomy is indicated.
Many liquid diets are available, with varying sources and composition of protein, fat, and carbohydrates. This variety usually allows the choice of an appropriate formula for the individual patient based on the composition of the formula, the underlying diagnosis, and the physiology of the GI tract. The types of formula commonly recommended for surgical patients, their essential qualities, and indications for each range in energy content to provide adequate protein for healing and growth.
Transesophageal tubes may cause gastroesophageal reflux, which can, in turn, lead to esophagitis, esophageal stricture, and aspiration pneumonia. Unless positioned and monitored carefully, they may inadvertently be placed into the trachea, leading to aspiration of feeds. Abdominal cramps and diarrhea may occur if tube feeds are introduced too rapidly. This may be avoided by starting with dilute formula at a reduced rate and gradually working up to full feeds. Gastrojejunal feeding tubes require frequent replacement and repositioning. A simple jejunostomy may be preferable, especially for long-term use.
Total parenteral nutrition (TPN) is indicated when the GI tract is not accessible or not functioning (e.g. mechanical obstruction, paralytic ileus, malabsorption), when gut rest is needed (e.g. proximal enterocutaneous fistula), or when oral or enteral feeding does not meet the patient’s nutritional needs. TPN should be started at any time, if enteral feeding will clearly not be possible for at least 7 days.
The choice of venous access for parenteral feeding primarily depends on the duration of TPN. For short-term needs, peripheral intravenous lines can be used as long as 7-10 days. Percutaneous non-tunneled central venous lines may also be used for short courses of TPN (as long as a few weeks). Peripherally inserted central venous catheters (PICVCs) can be used in all age groups, from premature neonates to adults, and can be maintained for weeks to months, thereby greatly reducing the need for needle sticks. When long-term TPN is required, a tunneled, cuffed, silicone rubber catheter is preferred.
TPN solutions are designed to include all the basic nutrients that patients require for maintenance of normal body composition, growth, and tissue repair. These include protein, energy, carbohydrate, lipid emulsion, water, electrolytes, minerals, and trace elements.