Introduction - What is Parenteral Nutrition?
Parenteral nutrition is the administration of a nutritional solution by infusion. All the necessary nutrients are fed directly into the vein. This bypasses the digestive tract, i.e. the stomach and intestines.
A further distinction is made between total parenteral nutrition (TPE), in which all food is administered intravenously, and supplementary parenteral nutrition (SPE), in which additional oral (normally via the mouth) or enteral nutrition (e.g. via a gastric tube) is carried out becomes.
Parenteral nutrition is always necessary when the patient is unable or insufficiently able to take in nutrients in the normal way.
How does parenteral nutrition work?
In the case of parenteral nutrition, an infusion solution is given that contains all the necessary nutrients and thus the patient is given as many calories as he needs.
The access route for parenteral nutrition is usually a central venous catheter (CVC), which is inserted into a large vein such as e.g. the subclavian vein and is advanced into the superior vena cava. If it is foreseeable that parenteral nutrition will be carried out over a longer period of time, a port system can be used as an alternative. A large vein is also punctured here and a chamber is placed under the skin, which can then be pierced from the outside. A port is created under general anesthesia.
As a short-term solution, a low-calorie solution can also be given via a normal peripheral venous catheter. High-calorie nutritional solutions or the administration of nutritional solutions over a longer period of time lead to vein irritation and are therefore not carried out.
When is parenteral nutrition used?
Parenteral nutrition is always used when it is not possible for the patient to get his nutritional requirements through oral (via the mouth) or enteral nutrition (via a gastric tube).
Reasons for parenteral nutrition can be:
Bleeding in the gastrointestinal tract
Absorption disorders in the gastrointestinal tract
Transport disorders: intestinal obstruction or tumors
severe courses of inflammatory bowel disease
severe burns or trauma
Chemotherapy or radiation therapy
What are the alternatives?
Alternatives to parenteral nutrition are enteral or oral nutrition whenever possible. These two forms of nutrition are always preferable to parenteral nutrition.
Enteral feeding is feeding through a gastric tube. It has the advantage that it is easier to carry out. In addition, the intestinal activity is stimulated and a decline in the gastric mucosa is prevented. Electrolyte imbalances (severe changes in blood salts) are also less common with enteral nutrition.
If enteral nutrition is not possible for any reason, parenteral nutrition is the last resort to ensure adequate nutrition.
Are there any contraindications?
A contraindication is the existing possibility of enteral nutrition. This form of nutrition is always preferable to parenteral nutrition. Another contraindication to parenteral nutrition is metabolic imbalance. Even if it is not ethically justifiable or if the patient refuses artificial nutrition, these are contraindications to parenteral nutrition.
Is that also possible at home?
Home parenteral nutrition is possible. Care should be provided by an outpatient nursing service or a caring relative. Relatives can learn the correct and safe handling of the entrances and important hygiene measures in various training courses.
Risks and Complications
Most of the complications associated with parenteral nutrition are due to the catheter or port system. The catheter may be incorrectly positioned and the nutritional solution does not get into the vein but into the surrounding tissue, where it can lead to irritation. Furthermore, it can lead to inflammation by germs in the area of the access routes. A blockage of the catheter due to thrombosis (blood clots) is also a possible complication.
Incorrectly composed nutritional solutions harbor the risk of serious shifts in blood salts (electrolyte derailment) or an excess of sugar.
Composition of the nutritional solution
The nutritional solutions for total parenteral nutrition consist of the following ingredients:
Carbohydrates (mostly glucose)
Vitamins and trace elements
The individual amount of the individual substances depends on various factors such as the patient's energy requirements and whether oral or enteral nutrition is also provided.
On the one hand, ready-made solutions with fixed proportions of the individual ingredients can be used. Alternatively, the nutritional solutions can also be put together individually and adapted to the needs of the patient.
The aim of parenteral nutrition should be to maintain body weight, to be able to maintain all body functions and to prevent malnutrition.
Cost of parenteral nutrition
The cost of parenteral nutrition varies greatly depending on the manufacturer and composition of the nutritional solution. The daily costs for total parenteral nutrition can be between 100-500 €. If the parenteral nutrition takes place during an inpatient hospital stay, the costs are covered by the health insurance company.
If artificial nutrition is continued at home, most health insurances will cover the costs of the nutritional solutions and the necessary materials, with the exception of a small additional payment. You should always ask your health insurance company for individual information.