Principles of the Parenteral Nutrition – Food&Nutrition Example

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"Principles of the Parenteral Nutrition " is an incredible example of a paper on food and nutrition. Parenteral nutrition is the administration of nutrients via the intravenous route. It is required in malnourished patients or in those who bear a risk of developing malnutrition and who possess a malfunctioning or an inapproachable gastrointestinal tract; so that the tube feeding (enteral feeding) cannot be administered. Such patients have a very fast deterioration rate if their nutritional demands are not fulfilled. Malnutrition leads to very poor recovery from any illness or surgical procedure. A sufficient intake of essential nutrients is mandatory for better healing of wounds, tissue maintenance, and a rapid recovery.

Parenteral nutrition or total parenteral nutrition (TPN) thus helps to meet all these requirements and prevents such patients from developing malnutrition who are unable to take oral feed and in whom enteral feed is not possible. There are special feeds prepared for parenteral nutrition which contain a balanced mixture of essential nutrients. This method of nutrition has specific indications and is based on certain principles that are described in the detailed discussion. Also, parenteral nutrition carries certain risks and has many complications especially if used for a long time.

These complications can be prevented by having a forehand knowledge of the initial requirements of the fluids, electrolytes, and essential nutrients for the patient before administration of the parenteral feeding. Moreover, the whole period of assisted nutrition should be accompanied by regular monitoring of the patient’ s fluid and electrolyte needs in order to prevent any overload of specific nutrients and thus preventing possible complications. Parenteral nutrition                                                                                                                                3 Parenteral nutrition is also called as ‘ hyperalimentation’ . There are two types of parenteral nutrition: Partial parenteral nutrition (PPN) and Total parenteral nutrition (TPN). PARTIAL PARENTERAL NUTRITION: Partial parenteral nutrition is indicated in those patients who are able to take some oral intake of food, yet are unable to ingest the sufficient amounts of nutrients required.

So their deficiency is fulfilled with partial parenteral nutrition using a peripheral intravenous catheter. The partial parenteral nutrition is administered in two forms: Lipid emulsions and Amino-acid dextrose solutions. TOTAL PARENTERAL NUTRITION: The total parenteral nutrition is indicated in cases where there is a need for intensive nutritional support for a prolonged period of time.

It is administered using a central approach through a central venous catheter. The total parenteral nutrition consists of the high concentrations of proteins and dextrose. Additional components are added as required. These may include electrolytes, minerals, trace elements, and insulin, etc.   Parenteral Nutrition                                                                                                                              4 Both of the above-described types of nutrition can be administered in a medical setup as well as at home. When administration at home is advised, the central venous catheter is used. The patient has first inserted a central venous catheter at a medical setup and then allowed to go home and continue the parenteral nutrition. PRINCIPLES OF PARENTERAL NUTRITION: Parenteral nutrition is used in situations where the patient is not able to tolerate oral or tube feeding.

These include the patients with severe pancreatitis, severe form of inflammatory bowel disease, short bowel syndrome, critically ill patients, gastrointestinal fistulas, low birth weight infants, cancer patients receiving blood cell transfusions or any such condition in which there is an intestinal failure to such an extent which prevents adequate absorption of nutrients into the gastrointestinal tract. Parenteral nutrition is basically composed of three components.

These include: Macronutrients, Micronutrients and   The macronutrients include: Carbohydrates as dextrose, Proteins as amino acids and Lipids as triglycerides. The micronutrients include: Parenteral Nutrition                                                                                                      5 Electrolytes, Trace elements and   When considering a patient for administration of parenteral nutrition, the following important principles must be kept in mind: Whether parenteral nutrition is truly indicated or not. A detailed assessment of the patient’ s history, drug profile, anthropometric data, and investigations should be made. Indications and need for a long-term or a short-term intravenous assessment. Determination of the estimated kilocalories, proteins, and lipid requirements as under:   Kilocalories: 20-30 kcal/kg. Proteins: 0.8-1.5 gm/kg. (severe catabolic state may be required even higher levels). Lipid to give about < 30% of kilocalories.   A forehand determination of the initial requirements of electrolytes, vitamins, and trace elements along with keeping in mind the ongoing losses. Additional requirements according to the needs of the patient like adding insulin or H2 receptor blockers. Assessment of the patient for:   Parenteral Nutrition                                                                                                                6 Risk of developing the refeeding syndrome or Glucose intolerance.   Trophic feedings in the case of neonates. Given below are the standard requirements for the administration of parenteral nutrition: Substance Normal patient High stressed Fluid restricted Amino acids 85g 125g 75g Dextrose 250g 350g 250g Lipids 100g 100g 50g Sodium 150mEq 155mEq 80mEq Potassium 80mEq 80mEq 40mEq Calcium 360g 360mg 360mg 180mg Magnesium 240mg 240mg 120mg Acetate 72mEq 226mEq 134mEq Chloride 143mEq 145mEq 70mEq Phosphorus 310mg 465mg 233mg VMI-12 10mL 10mL 10mL Trace elements                                 5mL                           5mL 5mL       Parenteral Nutrition                                                                                                                            7 INDICATIONS FOR PARENTERAL FEEDING: There are specific conditions that imply the use of parenteral nutrition in a patient.

Parenteral nutrition may be needed for a short or a long period of time depending upon the disease and condition of the patient. Both these indications are listed below: Indications for short term parenteral nutrition Indications for long term parenteral nutrition Severe pancreatitis Inflammatory bowel disease Intensive chemotherapy leading to mucositis Radiation enteritis Multi-organ failure Motility disorders (as scleroderma) Prolonged NPO after an excisional surgery Severe short bowel syndrome High output fistula or enterococcus fistula Chronic malabsorption   Nbvgsfbr7bih0789pouiuiun jhimjiijtitjfgtyir6Generally it is recommended that the patient receiving parenteral nutrition should be fed for about more than five days in order to outcast the complications associated with this kind of nutritional support. COMPLICATIONS OF PARENTERAL NUTRITION: Parenteral nutrition can lead to many complications if it is not managed properly and an expert hand and detailed knowledge are essential for this method of nutrition to be carried out successfully. Metabolic complications are the foremost to appear in relation to the glucose, amino acid, lipids, electrolytes, or vitamin disturbances. Parenteral Nutrition                                                                                                    8 Hyperglycemia is the most common complication and is directly related to the dextrose content of parenteral nutrition. Refeeding syndrome is another complication that arises as a result of the sudden provision of a large number of glucose calories to a patient who was previously malnourished.

This increased amount of glucose leads to increased release of insulin. Insulin shifts potassium, phosphorus, and magnesium into the intracellular compartments. This leads to hypokalemia, hypophosphatemia, and hypomagnesemia. Consequently, there are disturbances in sodium balance leading to sodium retention and large fluid shifts which may risk the patient for developing congestive heart failure. Abnormalities of certain liver function tests may occur including elevated levels of serum aminotransferases and bilirubin, especially in case of long term use of parenteral nutrition.

This may require a need for investigations to exclude the possibility of viral hepatitis, sclerosing cholangitis, autoimmune hepatitis, and biliary cirrhosis. The complications related to intravenous line insertion include pneumothorax, haemothorax, and air embolism. The access routes of parenteral nutrition may be complicated by thrombophlebitis, central vein thrombosis, and line infection. Parenteral nutrition is an important method of administration of essential nutrients in critically ill patients who are at risk of developing malnutrition and in whom tube feeding is not possible, yet it is a method that needs great expertise in order to get satisfactory results.

Either partial or complete parenteral nutrition, it needs a continuous evaluation of the status of the patient with the help of investigations so that we can prevent the possible complications of parenteral nutrition. Parenteral Nutrition                                                                                                      9   Moreover, the feeding regimes should be obtained from a pharmacy production unit in the form of compound solutions or standardized feeds in order to be more accurate with the nutritional requirements of the patient according to the diseases involved.


• Webster, J., Madden, A. , Holdsworth, M. (2006), Oxford Handbook of Nutrition and

Dietetics: New York, NY: Oxford University Press.

• Feldman, M., Friedman, L., Brandt, L. (2010), Sleisenger and Fordtran’s Gastrointestinal and

Liver Disease: Canada: Saunders.

• Parenteral Nutrition (2012): Wikipedia; The Free Encyclopedia; Retrieved from:

• Parenteral Nutrition (2012): eNotes; Study Smarter; Retrieved from:

• Compounding Parenteral Nutrition Admixtures (2007): Pharma Corner; Retrieved from:

• Parenteral Feeding (2012):; Retrieved from:

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