Total Parenteral Nutrition (TPN): NCLEX-RN
In this section of the NCLEX-RN examination, you will be expected to demonstrate your knowledge and skills of total parenteral nutrition in order to:
- Identify side effects/adverse events related to TPN and intervene as appropriate (e.g., hyperglycemia, fluid imbalance, infection)
- Educate client on the need for and use of TPN
- Apply knowledge of nursing procedures and psychomotor skills when caring for a client receiving TPN
- Apply knowledge of client pathophysiology and mathematics to TPN interventions
- Administer parenteral nutrition and evaluate client response (e.g., TPN)
As discussed previously in the section "Providing Client Nutrition Through Continuous or Intermittent Tube Feedings", clients who are not able to get sufficient calories and nutrition are given enteral nutrition through a nasointestinal tube, a nasojejunal tube, a nasoduodenal tube, a jejunostomy tube, a gastrostomy tube, or a percutaneous endoscopic gastrostomy (PEG) tube.
Although parenteral nutrition is more costly than enteral nutrition and it also poses a greater risk in terms of infection, it is sometimes indicated when enteral nutrition is contraindicated for the client, when the client is at high risk for aspiration, when the client has a gastrointestinal tract obstruction that would interfere with an enteral tube feeding, and when the client's gastrointestinal tract is not functioning in a manner that can accommodate a less costly and lower risk enteral feeding rather than total parenteral nutrition, which is often referred to as hyperalimentation.
Hyperalimentation places the client at high risk for infection for two major reasons; hyperalimentation is an invasive procedure and the hyperalimentation solution contains a high percentage and amount of dextrose.
The side effects and adverse events related to TPN include those described below.
- Complications associated with the insertion of the TPN catheter: Some of the complications associated with the insertion of the TPN catheter include an accidental and inadvertent pneumothorax, hemothorax or hydrothorax when the TPN catheter perforates the vein and fluid enters the pleural space. The signs and symptoms of these insertion complications include chest pain, shortness of breath and pain.
- Infection: Infection is probably the most commonly occurring complication associated with total parenteral nutrition. This complication can be prevented and minimized by using total parenteral nutrition only when necessary, by discontinuing the total parenteral nutrition as soon as possible, and by using strict sterile technique during its insertion, care, and maintenance. Most sources of infectious pathogens enter this closed system during insertion, tubing changes, dressing changes, and when total parenteral nutrition solutions are mixed. The signs and symptoms of these infections include the classical signs of infection including a fever, malaise, swelling and redness at the insertion site, diaphoresis, chilling and pain in the area of the TPN catheter insertion site.
- Fluid overload: Fluid overload can occur for the same reasons that fluid overload can occur with a regular peripheral intravenous flow. The rate is too fast and rapid for the client. The signs and symptoms of fluid overload include hypertension, edema, adventitious breath sounds like crackles and rales, shortness of breath, and bulging neck veins. This complication can be prevented by monitoring the client and adjusting the rate of the total parenteral nutrition to prevent fluid overload.
- Hyperglycemia: Hyperglycemia can occur as the result of the high dextrose content of the total parenteral nutrition solution as well as the lack of a sufficient amount of administered insulin. The signs and symptoms of hyperglycemia secondary to total parenteral nutrition are the same as those associated with poorly managed diabetes and they include a high blood glucose level, thirst, excessive urinary output, headache, nausea and fatigue. This total parenteral nutrition complication can be prevented with the continuous monitoring of the client's blood glucose levels and the titration of insulin administration as based on these levels.
- Hypoglycemia: Hypoglycemia secondary to total parenteral nutrition are the same as those associated with poorly managed diabetes and they include a headache, a low blood glucose level, shakiness, clammy and cool skin, blurry vision, diaphoresis and unconsciousness and seizures. This complication of total parenteral nutrition, like hyperglycemia, can be prevented with the close monitoring of the client's blood glucose levels and an adequate dosage of insulin as based on these levels.
- Embolism: Embolism can occur when air is permitted to enter this closed system during tubing changes and when a new bottle or bag of hyperalimentation is hung. This complication can be prevented by instructing the client to perform the Valsalva maneuver and the nurse's rapid changing of tubings and solutions when the closed system is opened to the air. The signs and symptoms of an embolism include dyspnea, shortness of breath, coughing, chest pain and respiratory distress.
Clients should be educated and instructed about the purpose of TPN, their need for TPN, the procedure that will be used to insert the TPN catheter, how the total parenteral nutrition feedings will be delivered, how the nurse will care for and maintain these feedings, the necessity to use sterile technique, and the risks, including the complications, of total parenteral nutrition, as discussed immediately above .
Total parenteral nutrition, or hyperalimentation, is delivered through one of the body's larger veins such as the subclavian vein. Hyperalimentation can provide for all of the nutritional needs and these feedings contain minerals, electrolytes, vitamins, hyperosmolar glucose, amino acids, and trace elements which are administered through the hyperalimentation catheter which was surgically placed by the physician.
Total parenteral nutrition is most often used for clients who are in need of complete bowel rest, those who are in a negative nitrogen balance as the result of a severe burn or another cause, among clients who have a severe medical illness or disease such as cancer or AIDS/HIV, when the client chooses to have this treatment.
Applying a Knowledge of Nursing Procedures and Psychomotor Skills When Caring for a Client Receiving TPN
The nursing process as applied to the nursing procedures and the psychomotor includes assessment, nursing diagnoses, planning, establishing expected outcomes and evaluating the client's responses to this care and treatment.
Assessment: The nurse assesses the client, they assess and validate the client's need for hyperalimentation including laboratory diagnostic test results, and they also establish baselines prior to the total parenteral nutrition feedings which include baseline bodily weight, baseline vital signs, baseline levels of glucose, protein and electrolytes, and baselines in terms of the client's intake and output.
After the complete assessment of the client, the nurse will establish actual and potential nursing diagnoses for the client such as:
- Imbalanced nutrition less than the body requirements related to advanced debilitating disease
- Imbalanced nutrition less than the body requirements related to a negative nitrogen balance secondary to a severe burn
- Imbalanced nutrition less than the body requirements related to an impairment of gastrointestinal tract functioning
- At risk for hypoglycemia related to total parenteral nutrition
- At risk for hyperglycemia related to total parenteral nutrition
- At risk for sepsis related to total parenteral nutrition
- At risk for sepsis related to total parenteral nutrition
The planning phase of the nursing process in respect to total parenteral nutrition includes the establishment of client goals or expected outcomes and planning interventions. Some appropriate expected outcomes can include:
- The client will be free of any complications associated total parenteral nutrition
- The client will have adequate nutrition
- The client will maintain normal blood glucose levels during treatment with total parenteral nutrition
- The client will be able to verbalize an understanding of total parenteral nutrition and the need for sterile asepsis
The evaluation of the total parenteral nutrition for the client is based on comparing the client's baseline data and information to the data and information that is collected during these treatments and after the total parenteral nutrition feedings are completed, as will be discussed just below in the section entitled "Administering Parenteral Nutrition and Evaluating the Client Responses".
Some of the psychomotor skills that nurses used when caring for a client receiving TPN include the nurse's application of sterile asepsis techniques, changing the tubings and the total parenteral nutrition feeding bags and bottles, the maintenance of the site of insertion of the total parenteral nutrition catheter, and manipulating and controlling the rate of the infusion of the total parenteral nutrition. More information about these psychomotor procedures will be discussed just below in the section entitled "Administering Parenteral Nutrition and Evaluating the Client Responses."
Nurses caring for clients who are receiving TPN must apply their knowledge of the client's physiology into their care of the client. For example, they must apply sterile technique to avoid infection, they must closely monitor the client's blood glucose levels on a continuous basis because the contents of these total parenteral nutrition feedings are high in terms of dextrose content which can lead to hyperglycemia, they must also monitor these levels to determine if the client is being affected by hypoglycemia as a result of the insulin that is administered with these total parenteral nutrition feedings in order to prevent hyperglycemia, and, for example the nurse must monitor the client's intake and output knowing that, physiologically, the high osmolarity of the TPN can lead to osmotic diuresis and fluid imbalances.
Mathematic principles are also applied to TPN interventions in terms of flow rate of the solution which is essentially the same as calculating intravenous flow rates which was fully discussed and described in the section entitled "Dosage Calculations: Performing Calculations Needed for Medication Administration".
Total parenteral nutrition is administered in a similar manner to that which is done with intravenous infusions with a few points of emphasis and differences as listed below.
- Total parenteral nutrition feedings are refrigerated until they are ready to hang
- Strict sterile asepsis is used.
- Regular insulin can be added to the TPN solution to prevent hyperglycemia
- Any time that this closed system is opened, as occurs with a tubing or solution bag change, the client must perform the Valsalva maneuver to prevent an embolus and the nurse must perform these tasks as quickly as possible.
- The total parenteral nutrition tubing should be changed every 24 hours and the dressing should be changed at least every 24 hours for the first several days of treatment. These changes can vary from facility to facility, so nurses must refer to their facility specific policies and procedures
- Adverse Effects/Contraindications/Side Effects/Interactions
- Blood and Blood Products
- Central Venous Access Devices
- Dosage Calculations
- Expected Actions/Outcomes
- Medication Administration
- Parenteral/Intravenous Therapies
- Pharmacological Pain Management
- Total Parenteral Nutrition - TPN (Currently here)