Home Care of the Patient Receiving TPN
Home Care of the Patient Receiving TPN
Nurses must be vigilant in monitoring for subtle changes that may spell trouble
Carrie T just got home from the hospital after being diagnosed with pancreatic pseudocyst. She had worked at the airport as a reservations agent for a major airline and was anxious about being away from work for so long. Her husband owned a small business and worked long hours. Their children were 16 and 17 and in high school.
Carrie had a bout of pancreatitis 10 years ago, which cleared up after a week in the hospital receiving IV fluids. However, with this latest flare-up she was in the hospital for two weeks and the most recent MRI and CT scan still show that the cyst is 12 cm by 9 cm. As part of her treatment, Carrie had a pancreatic drain in place requiring irrigation with normal saline twice a day to keep the tubes open. She was to be npo except for sips of water.
As a home health care nurse, I had to teach Carrie how to self-administer hyperalimentation, commonly referred to as TPN (total parenteral nutrition).
Indications For TPN
TPN was first administered in critical care bags in hospitals around 1952. As technology became more sophisticated and Medicare began to cover TPN under the prosthetic device benefit, it eventually became available and routinely administered for home use.
The American Society for Parenteral and Enteral Nutrition (ASPEN) develops guidelines for TPN administration. Common diagnoses for its administration are listed in Table 1.
Usage also changes with new research and drug development. For example, in the early 1990s home care nurses routinely cared for patients with AIDS wasting who were receiving TPN. With the advent of protease inhibitors, TPN is not as common in the AIDS population at home. (Protease inhibitors are one of the newest drug classifications in the treatment of AIDS. They inhibit HIV-1 and HIV-2 proteases. HIV protease is an enzyme required for viral cleavage into the individual. The protease inhibitors "inhibit" this process and thereby decrease viral load.)
Contraindications for TPN when ordered properly are rare. However, contraindications would include: inborn error of protein metabolism, such as maple syrup urine disease and isovaleric acidemia. TPN should be used with extreme caution in low birth weight neonates, renal insufficiency or failure, liver disease and cardiac impairment.
Patients must have central venous access for TPN administration. Therefore, lack of central venous access can also prevent administration of TPN. There is an associated risk of infection anytime anything is given via the venous system. In some cases the risk of infection may prevent administration of TPN.
Payment Guidelines For TPN
Medicare has strict guidelines for covering TPN, especially in the home health setting. For example, patients must have a non-functional GI tract (obstruction, inability to place enteral access, malabsorption and insufficient pancreatic enzymes). TPN is usually anticipated for at least 3 months as the sole source of nutritional support for patients with a total caloric intake of 20-35 cal/kg/day. Medicare requires justification of variations, such as when cal/kg/day are less than 20 or greater than 35, protein less than 1 or greater than 1.5 gm/kg, and/or dextrose less than 10 percent.
TPN patients must meet the Medicare guidelines for home care. That is:
- they must be homebound,
- under the supervision of a physician and
- require intermittent nursing,
- care must be reasonable, necessary and
- require a nurse's skills.
TPN costs about $200-$300 a day for a basic formula.
Traditional insurers generally want to get the patient out of the hospital as soon as possible. Therefore, you will see "just a day or two" of TPN given to the patient with private insurance. The requirements are specific to the individual insurance plan and will generally require pre-authorization for a patient to receive TPN.
The initial assessment for TPN needs to include coordination with the physician, nutritionist or dietitian and the pharmacist. Prior to administering TPN, the nurse will need the following information:
- Diagnosis and co-morbidities
- Nutrition status
- Prognosis/approximate length of therapy
- Cardiac function
- Diabetes (Is patient insulin dependent?)
- Renal and liver function
- Patient history, height and weight and systems assessment
In obtaining patient history, nurses should determine the extent of weight loss and how quickly it occurred. Nurses should note frequency of diarrhea or vomiting and explore dietary history including food allergies (especially eggs). Lipids will be contraindicated if the person is allergic to eggs.
The nurse should assess the patient's ability to learn self-administration, his financial ability and insurance coverage. Also important is the patient's environment, including the presence of a caregiver, availability of a phone, running water and refrigeration.
Carrie had lost 24 pounds in two months and had no history of diabetes. TPN was administered in the hospital for two weeks, and it was to be continued at home. Her labs when she first arrived home were renal function: BUN 19 mg/dl; creatinine 0.9 mg/dl--both within normal limits; liver function: albumin 2.6 g/dl (low), ALT 301 U/L (high), AST 304 U/L (high), ALP 527 U/L (high), triglycerides, 245 mg/dl (high). Other labs of note include amylase 415 U/L (high) and transferrin 110 mg/dl (low).
The low albumin and low transferrin show a compromised nutritional status. The high amylase indicates some pancreatic involvement. Altogether, these labs show moderate malnutrition.
Routine lab orders for TPN once the patient is stable include CBC, phosphorous, comprehensive metabolic panel, magnesium and triglycerides weekly. Transferrin is ordered monthly and at admission. Other labs such as amylase may be disease-specific if there is a pancreatic diagnosis. Carrie's amylase went as high as 1030 U/L, where the norm is less than 89.
Labs are ordered daily in the hospital, and typically done twice weekly in the home for a week or two until the patient is stable, then weekly for several months and then monthly. Long-term home TPN patient (Crohn's disease) labs may become as infrequent as every six months if the patient is stable and there are no formula changes.
TPN is made up of three major components--protein (amino acids), carbohydrates (dextrose), and fats (lipids), which are essential to adequate nutrition. Other minor components are trace elements, electrolytes, minerals, vitamins and added medications. Overall fluid is 20-30 cc/kg a day. A basic TPN formula comprises about 10 percent amino acids, 70 percent dextrose and 20 percent lipids.
Protein requirements for TPN patients will depend on their overall health status and should comprise 15 percent-20 percent of the overall calories, somewhere in the range of 0.8gm/kg (unstressed) to 2.5 gm/kg (severe stressed). Amino acids provide 4 cal/gm.
Dextrose is the carbohydrate source in TPN. This is also the factor that differentiates TPN from PPN (partial parenteral nutrition).
Dextrose concentrations of 10 percent or more are considered TPN and must be given via central venous access. Less than 10 percent dextrose can be given via peripheral venous access. Dextrose is commercially available in concentrations of 5 percent-70 percent. After mixing it with the other ingredients to make TPN, the final dextrose concentration is generally around 25 percent and will provide 50 percent of the total calories. Dextrose provides 3.4 cal/gm.
Most lipid solutions are made from soybean (or safflower) and eggs, so lipids may be contraindicated in patients with egg allergies, severe hyperlipemia, lipoid nephrosis or severe liver damage. Lipids can be administered separately from the amino acids and dextrose (2:1 solution) or they may be mixed together, which is commonly referred to as a 3:1 solution. Lipids come in 10 percent-20 percent concentrations and are generally given 1-1.5 gm/kg for about 30 percent of total calories. Lipids are 9 cal/gm. They can be given peripherally, although this is rarely done in the home.
Multivitamins and minerals are added to TPN daily. It is also common to add vitamin K, 10 mg weekly. Occasionally, vitamin C and folic acid may be added. Vitamin K may need to be eliminated if the patient is on warfarin therapy.
The electrolytes are adjusted in TPN based on the blood chemistries. These electrolytes include: magnesium, potassium, calcium, phosphorus and sodium. Labs should be drawn prior to the pharmacy mixing the TPN. In the hospital, TPN is often given over 24 hours, in three bags with each one being administered over eight hours.
Labs are drawn after each unit infuses. Thus, changes can be made without having to waste any of this expensive therapy.
Several common medications are frequently added to TPN. These include: heparin to prevent clotting on the catheter tip, regular insulin (remember, only regular insulin can be added to TPN) to regulate blood glucose levels, and anti-ulcer medications (cimetidine, ranitidine hydrochloride and famotidine). The hospital pharmacist does all the mixing under a laminar-flow hood; but in the home setting, medications should be added to TPN on a clean surface such as the kitchen table.
Complications of patients receiving TPN can fall into three basic categories: septic, mechanical and metabolic. Serious complications can often be avoided by careful patient monitoring.
Septic Complications--a disease-producing organism in the blood causes sepsis. Contamination can lead to sepsis and can occur with mixing, preparation, catheter connection, catheter site care or taking blood specimens. The most common cause of sepsis is catheter-related infection, which often occurs when strict aseptic technique is not followed or when the catheter is seeded with microorganisms. Good handwashing and aseptic techniques by nurses, caregivers and patients are imperative with handling TPN. Patients requiring TPN are often prone to infections because of their poor nutrition and disease process.
Signs and symptoms of sepsis include redness, tenderness and drainage at the IV access site; fever above 100.5 F; shaking chills; abscess and wound drainage changes; signs of UTI or URI. The most common organisms are Staphylococcus epidermis, Staphylococcus aureus, Candida albicans and gram-negative bacteria.
Antibiotics are used to initially treat infections, and catheter-site dressings are changed frequently. However, catheter removal may be necessary, especially if the infecting organism is a fungus. Early detection is imperative as is, and this can't be stressed often enough, teaching the patients and caregivers to use good handwashing and aseptic technique.
Mechanical Complications--Several mechanical complications may occur during TPN, of which the most common are occlusion, thrombosis, and breaks or leaks in the system. Some uncommon mechanical complications are air embolism, bleeding and cracked TPN. Listed below are complications and some solutions:
- Occlusion--Inability to irrigate the catheter, first check the clamp. Teach the patient to check the clamp first as this is the most common problem. If the catheter will still not irrigate, do not use force to try to irrigate. Since urokinase has been taken off the market, tissue plasminogen activator (tPA)--not cost-effective in the home--may be administered in the hospital setting to prevent occlusions. Patients may require hospital treatment for this complication and may need to have the catheter replaced.
- Thrombosis--Blockage of the vessel with a clot can be a medical emergency. Monitor the access site for signs of redness, local tenderness, warmth, edema, palpable chord in the vessel, neck vein distention and discoloration of the extremity. Two home patients who called me had the complaint "my arm looks a little purple or bruised"--one had a PICC line and one had a Groshong catheter. In both cases, the arm was a little cool and dusky in color. They both were sent to the hospital where vein studies revealed huge clots in the vessel.
Another patient with a Hickman catheter developed a red streak in the jugular vein overnight. Again, after transport to the hospital, the vein study revealed a large clot. No matter how non-specific the patient's complaints are, the nurse must follow up, inspect the site and assess the patient.
- Breaks or leaks in the system--The most common cause of a leak in the system is not connecting properly or tightly. A leak can occur by spiking the bag through the bag and puncturing it, or by improperly connected pieces for whatever IV system is in use.
When connecting a patient to TPN, the IV tubing must be connected with some type of luer lock. This is standard on all IV tubing systems. What often happens is the patient does not twist far enough or push tight enough and the tubing is not really connected. Proper patient education can prevent this problem. This can leave a pathway open for microorganisms to enter. Double check all connections. From time to time a nurse will find defective equipment. When this happens, return it to the pharmacy so that they can follow up with the manufacturer.
A break in the system in the home setting is often from a patient who uses scissors near their catheter or tubing and cuts the line. This type of break will require a catheter repair and may necessitate the catheter being removed or changed.
Uncommon mechanical complications associated with TPN include air embolism, bleeding and cracked TPN.
Air embolism--Presents with cyanosis, tachycardia, tachypnea, dyspnea, chest pain and cardiac arrest, and intervention includes clamping the catheter as close to the body as possible, laying the patient on side with chin to chest, contact physician or 911 to transport.
Prevention includes using luer lock connections, always clamping the catheter prior to opening the system--the exception is a Groshong is only clamped when damaged--and if disconnection occurs, clamping immediately.
Bleeding--Free flow of blood from catheter. Interventions: clamp the catheter and flush as ordered. Prevention: secure all connections with luer lock connections, keep the height of pole mounted solution container at least 30 inches above the patient. Note: In the home, the pump is usually portable without a pole and pole height is not an issue.
Cracked TPN--TPN, which is 3:1 (amino acids, dextrose and lipids) can separate into its component parts. When this happens it can have an "oil and vinegar" look with a yellowish cast. If the TPN is not the usual milky white solution prior to adding the multivitamins it should not be administered. Multivitamins make the solution a pale yellow but the color is even throughout. Cracked TPN is an uneven color and dark yellow.
Metabolic Complications--Metabolic complications can occur during or after the administration of TPN. These complications (see Table 2) are often related to electrolytes and dextrose in the TPN reacting with the body.
Teaching TPN to patients will take some time. You will need to teach the underlying disease process as well as all aspects of monitoring and administration. Key factors include purpose of TPN, signs of catheter complications, pump troubleshooting, infection control, biohazard handling and TPN storage. Other factors are aseptic technique, hand washing, pump alarms, daily weight, monitor blood glucose, check expiration, emergency numbers for nurse, check temp q p.m., access-device care, complications and action to take, additive procedures, pump set up, check solution for cracked TPN, flushing procedure, record intake and output.
Social issues also are important to cover, especially since gatherings of family and friends with food are big social events in most cultures. Patients receiving TPN and their caregivers are therefore often excluded from social gatherings. With all the equipment needed to administer TPN in the home, it can start to take on the appearance of a hospital.
This was a big issue for Carrie's teenage daughter who felt she could not have friends over without needing to answer a bunch of questions about what all the stuff in the refrigerator was.
After teaching Carrie, I sat down with her children and helped them sort through their feelings. We worked together to come up with some solutions like keeping the TPN in the vegetable drawer where they did not have to see it every time they looked in the refrigerator. We discussed strategies for talking with their friends that enabled them to feel more comfortable. Eventually the daughter invited several friends for a sleep over while her mom was on TPN. As nurses, we must be prepared to meet all of the patient's needs.
Carrie eventually had her pancreatic pseudocyst drained and she was able to come off of TPN. She was able to return to work during her course of TPN. This occurred during the bowel/pancreas rest phase prior to surgery. After two days of twice-a-day nursing and one week of daily nursing, Carrie was independent in TPN take-down and administration. She progressed to nursing twice a week for labs, performance of routine site care and dressing changes to her Groshong.
Care of the TPN patient can be very rewarding because nurses assist someone in becoming independent in his care. However, there are numerous complications, so the nurse must be forever vigilant in monitoring for subtle changes that may spell trouble.
DeLegge, M. (1998). Home parenteral nutrition: A physician's perspective. Infusion, 4(7), 31-35.
Metheny, N. (1992). Fluid and Electrolyte Balance Nursing Considerations. (pp. 180-191). Philadelphia: J.B. Lippincott.
Viall, C. (1995, April). Taking the mystery out of TPN. Nursing95, 34-41.
Jan Rayl is a home IV nurse with INOVA-VNA, Alexandria, VA. Jan has been specializing in home health in Northern Virginia for the past 14 years.
Table 1: Indications for TPN
- Extensive surgery
- Multisystem trauma
- Crohn's disease
- Small bowel disease or resection (>70 percent resected)
- Moderate to severe pancreatitis
- Lack of gastrointestinal nutrient absorption, severe malnutrition
- Hyperemesis gravidarum
- Inflammatory bowel disease, obstruction or abdominal fistula
- Burns (>50 percent of body surface area)
- High-dose chemotherapy, radiation and bone marrow transplantation
Table 2: Metabolic Complications
Not much of a problem with continuous TPN but occurs frequently with cycled TPN. Signs & symptoms: Blood sugar over 250 mg/dl. Polyuria, polydipsia, polyphagia, "fruity" breath, confusion, irritability & coma. Interventions: Monitor glucose closely; taper the TPN up for the first hour; work the patient up to the full rate by slow incremental increases over one to two hours.
Signs & symptoms: Blood sugar less than 80 mg/dl. Dizziness, diaphoresis, visual disturbances, lethargy, irritability, tingling in extremities, hunger pangs, light headedness, which if severe can lead to coma & death. Interventions: Monitor glucose one hour after coming off the TPN; tapering off the TPN can prevent a dramatic drop in the blood sugar
Signs & symptoms: Peripheral sacral edema, weight gain, shortness of breath, tachycardia, wheezing & hypertension. Interventions: Monitor weight daily, notify physician if a gain of 5 or more pounds in one day; diuretics may be required.
Signs & symptoms: Thirst, weight loss (3 pounds or greater in 24 hours), dizziness, hypotension, dry mucous membranes, tenting of the skin and decreased urinary output. Assess for excessive fluid losses such as vomiting, diarrhea, diaphoresis & infection. Interventions: Monitor fluid intake & output as the fluid in the TPN may need to be adjusted.
Signs & symptoms: Serum sodium less than 120 mEq/L. Confusion, apprehension, cold clammy skin, orthostatic hypotension, nausea & vomiting, muscle twitching, tachycardia, polyuria or oliguria & decreased urine specific gravity. Interventions: Monitor intake & output including vomiting, diarrhea, drainage from wounds or fistulas; may need to obtain orders to decrease fluid or increase sodium in TPN.
True hypernatremia is rare and is usually a sign of dehydration. Signs & symptoms: Serum sodium level 150 mEq or greater. Hypotension, tachycardia, oliguria, thirst & poor skin turgor. Interventions: Administer free water to achieve sodium balance; monitor intake & output, monitor sodium levels.
Signs & symptoms: Serum potassium below 3.5 mEq. Muscle weakness, nausea, orthostatic hypotension, metabolic alkalosis, irregular heart rhythm, vomiting, parasthesia & weakness. Interventions: Adjust potassium in TPN; may need supplemental potassium. Monitor intake & output.
Signs & symptoms: Serum potassium 5.5 mEq or greater. Diarrhea, cardiac irregularities, muscle twitching, & oliguria. Interventions: Evaluate potassium administration; the exception would be in renal impairment where further medical intervention may be required.
LESS COMMON COMPLICATIONS
Hypophosphatemia, hypomagnesemia, essential fatty acid deficiency & trace element deficiency. Signs & symptoms: In general any side effects, new or unusual occurrences that the patient reports must be investigated. Teach patients that they should report anything new no matter how insignificant. Often something as simple as itching or "my brush is full of hair" can be clinically significant. These vague symptoms can be indicative of a trace element deficiency or an alteration in their electrolyte balance & further lab testing may be required.