What Is Parenteral Nutrition? Definition, Types, Benefits, and Uses

Parenteral nutrition is a technique of medical nutrition which supplies the nutrients required by the body by passing the line into the blood stream via an intravenous (IV) catheter. When individuals are inquiring what is parenteral nutrition, it means feeding the body with glucose, amino acids, lipids, vitamins, and minerals via a non-digestive method of feeding.

This treatment is a common treatment when the digestive tract is unable to absorb and digest nutrients as usual due to disease, surgery or other extreme gastroenterological diseases. Parenteral nutrition in hospitals and critical care units is important in the support of patients who are not able to eat, digest food, or have sufficient nutrition by alternative methods of feeding.

What Is Parenteral Nutrition?

Parenteral nutrition is a medical practice of supplying the body with the necessary nutrients by way of an intravenous (IV) infusion. When speaking of what is parenteral nutrition, it means being able to provide nutrition without using the digestive system and allowing the body to get the nutrients in the event that normal eating or digestion cannot take place. This therapy has essential nutrients like carbohydrates, proteins, fats, vitamins, minerals and electrolytes required to provide energy and body functions. Parenteral nutrition is used to assist patients who are unable to obtain nutrients via the stomach tract and surgery or with serious gastrointestinal conditions.

Types of Parenteral Nutrition

Parenteral nutrition may be administered in various forms which depend on the medical condition and the nutritional requirements of a patient. They are the Total Parenteral Nutrition (TPN) and the Peripheral Parenteral Nutrition (PPN). Both approaches vary in the path of administration, concentration of nutrients and the course of treatment in clinical care.

Total Parenteral Nutrition (TPN)

Total Parenteral Nutrition (TPN) is the complete nutritional support system in case the patient is unable to use the digestive tract in any way possible. It is given by injection into a central vein, typically by a catheter inserted into a great vein like the superior vena cava. TPN is a complete combination of all nutrients such as carbohydrates, amino acids, lipids, vitamins, minerals, and electrolytes. This form of therapy is often employed in patients who have severe gastrointestinal illness, intestinal obstruction or following major surgery in cases where the patient cannot be allowed to eat orally or enterally.

Peripheral Parenteral Nutrition (PPN)

In a smaller peripheral vein (mostly in arms), Peripheral Parenteral Nutrition (PPN) is a type of parenteral nutrition. It is mostly applied in the case of short-term nutritional assistance, in patients who are unable to sustain their nutritional demand by oral nutrition, but still have partially functioning digestive systems. The low levels of nutrients in PPN solutions are used in place of TPN to avoid irritation of the peripheral veins, which makes it an appropriate intervention in temporary nutrition therapy.

Components of Parenteral Nutrition

Parenteral nutrition offers a balanced combination of vitamins which are normally absorbed in food. These nutrients are used with caution in TPN nutrition therapy to provide the energy, body functions, and metabolic balancing in patients who are unable to receive nutrition via the digestive system.

1. Carbohydrates (Dextrose): Carbohydrates form the major constituent of energy in parenteral nutrition. It supplies us with calories to the body which are required to sustain cellular activities, brain processes as well as normal body metabolism.
2. Amino Acids: Amino acids provide protein that is needed in repairing the tissues, maintaining the muscles and the immune system. They are required to stimulate growth and recovery particularly in patients who are critically ill or malnourished.
3. Lipids (Fats): Lipids give extra calories and fatty acids that are necessary in energy and structure of the cell. They also aid in avoiding the essential fatty acid deficiency in the course of a long-term parenteral nutrition treatment.
4. Electrolytes: Electrolytes (sodium, potassium, calcium and magnesium) assist in balancing the fluids and also in the adequate functioning of the nerves and the muscles. They are also monitored closely so as to ensure stability in body chemistry.
5. Vitamins and Trace Elements: Vitamins and trace elements help in sustaining key metabolism and bodily enzyme processes. All these micronutrients are required in order to be more immune, healed and in a balanced state in terms of physiology.

Indications for Parenteral Nutrition

Parenteral nutrition is applied to a patient who cannot receive the proper nutrients by normal digestion or even by oral feeding. In case of a critical gastrointestinal pathology or intestine blockage, the digestive system may not work effectively, and intravenous feeding is required to maintain the energy level and provide the body with the necessary functions.

The conditions that also hint it include short bowel syndrome, severe malnutrition or post major gastrointestinal surgery. Under such circumstances, parenteral nutrition is necessary to supply patients with essential nutrients, into the blood, to ensure nutritional balance is maintained, and patients obtain the necessary nutrition, as the digestive system is recovering.

Benefits of Parenteral Nutrition

• Offers basic nutrients: Delivers basic nutrients to the bloodstream where the patients are unable to eat or digest the food.
• Prevents malnutrition: Assists in the maintenance of adequate nutritional conditions in patients who cannot be administered enough nutrients via oral or enteral feeding.
• Helps in recovery: It gives the right energy and nutrients to promote healing and recovery in a state of critical diseases or following major surgery. 
• Maintains metabolic balance: This is the maintenance of balance of nutrients that are required to give energy and maintain metabolic stability.
• Help patients with gastrointestinal disorders: Helps to feed patients who have other conditions such as bowel obstruction, short bowel syndrome or severe Crohn disease when the digestive system is unable to work properly.
• Individualized nutrition: Parenteral nutrition may be individualized to address the specific needs of an individual patient such as vitamins, minerals, electrolytes, and caloric needs.
• Improves quality of life: Helps patients to be strong, energetic and able to continue with their day to day functioning when they are not able to eat on normal days, particularly in long-term illnesses. Lowers the workload of the digestive system: It will also give the digestive system time to relax and heal by avoiding the gastrointestinal tract, since it is favorable in case of severe inflammation or damage.

Possible Complications of Parenteral Nutrition

In spite of the fact that parenteral nutrition is the necessary nutritional support some complications might be met during the treatment. It has been widely known that the problem of infection of the intravenous catheter site is one of the key issues that should be addressed with utmost sterile methods during the insertion and maintenance of the catheter. Electrolytes imbalances can also arise when one does not closely observe the levels of nutrients during therapeutic intervention.

The parenteral nutrition used in the long run sometimes impacts on the liver that results in liver related complications among some patients. Moreover, there are also changes in the level of blood glucose due to the presence of dextrose in the solution. Due to this reason, healthcare providers constantly check the blood glucose levels, liver and electrolyte concentration to guarantee patient safety and successful treatment.

Nursing Considerations for Parenteral Nutrition

The safe administration of parenteral nutrition, as well as prevention of potential complications during the course of therapy, presupposes proper nursing care. Close attention should be paid by nurses to the change in the level of blood glucose since the dextrose in parenteral nutrition solutions may lead to the variations which can influence the metabolic equilibrium and general health condition of the patient.

To minimize the risk of catheter related infections there should be a strict adherence to sterile technique when handling intravenous lines and catheter sites. Electrolyte levels, fluid balance and vital signs should also be monitored by nurses on a regular basis. Redness, swelling, fever, or discomfort at the catheter site are complications that can be easily observed and thus safe parenteral nutrition therapy may be offered.

When Is Parenteral Nutrition Necessary?

Doctors apply the TPN nutrition therapy in situations where the patient is unable to get the necessary nutrition either by normal meal intake or by the digestive system. This can be done under the circumstances of serious gastrointestinal diseases, obstruction of the intestines, short bowel syndrome or following significant abdominal surgery where the digestive tract is unable to absorb nutrients appropriately.

Parenteral nutrition is used in this case to feed the body with the necessary nutrients through direct delivery into the bloodstream to sustain energy levels and assist the body processes. Therapy is determined by the length of time spent based on the condition of the patient and the progress of recovery. It might have to be used temporarily by some patients during the healing process, and the nutritional support might be provided to others in the long term with professional medical attention.

Conclusion

What is parenteral nutrition important to know about parenteral nutrition since it has a crucial role in contemporary medical practice. Parenteral nutrition is the provision of nutrients straight into the blood in the cases where patients cannot either eat or pass the food through the digestive system. This therapy helps maintain energy requirements, it causes malnutrition to be checked, and a patient bounces back after a severe illness or a prolonged surgical operation. It is also in most instances a life-saving nutritional therapy to patients with extreme gastrointestinal problems. Nevertheless, parenteral nutrition should never be used without appropriate medical guidance and regular check-ups in order to prevent threats and ineffectiveness.

Medical Disclaimer

The paper is educational and should not substitute professional medical care. Only when medically regulated should parenteral nutrition be administered. Patients are to be diagnosed and treated by qualified health professionals who would provide an opinion on nutrition therapy and other medical conditions.

References 

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