Questions you should ask your doctor if you are on long-term home parenteral nutrition
Shirley Paski, MD
Why am I on TPN?
- Calories from fat, protein, carbohydrates?
- Vitamins and minerals?
Is there a way to make my gastrointestinal system function so that I don’t need TPN, or need less TPN?
- Significant individual variation
- Unable to eat enough food
- Nausea, vomiting
- Abdominal pain, distention
- Unable to break down food into particles that can be taken up into intestinal cells
- Not enough intestine,
- Intestines are damaged, and/or
- Rapid transit of food through the intestines, without enough time to be absorbed
What vitamin and mineral deficiencies am I at risk for developing?
- Depends on which part of your gastrointestinal tract is missing and how well your other organs like the pancreas and liver function
- In short bowel syndrome, fat-soluble vitamin deficiency, vitamin B12, magnesium, and potassium deficiencies are most common
- Iron deficiency is common in home parenteral nutrition because iron is not in the TPN
How often should I be getting labs done to make sure I’m not developing nutritional deficiencies or toxicities?
- Variable, and depends on how ‘dependent’ you are on TPN vs oral diet vs tube feeding
- General guide that I follow (with individual modifications):
- MONTHLY: CBC, CMP, magnesium, phosphorus, INR, CRP, pre-albumin, triglycerides
- EVERY 3-6 MONTHS: Iron indices, zinc, selenium, copper, carnitine (pediatric patients)
- EVERY 6-12 MONTHS: Vitamin B12, folate, vitamin A, vitamin E, 25-OH vitamin D, vitamin C, chromium, manganese
- ANNUAL: PTH, TSH, full lipid profile; 24-hour urine sodium, creatinine, calcium
What are the possible long-term effects of TPN on my body?
- Long-term effects of TPN can be directly caused by TPN, the result of underlying gastrointestinal disease, lack of nutrient exposure to the gut, fluctuations in hydration/electrolytes, or to IV access.
- Nutritional – over/under nutrition, vitamin/mineral deficiencies or toxicities
- Liver – elevated liver enzymes
- Chronic renal (kidney) injury – low glomerular filtration rate (GFR)
- Metabolic bone disease – osteoporosis, osteopenia
- Central catheter and IV access – line infections, blood clots, difficult IV access
How can I reduce my chance of developing long-term complications related to TPN?
- Screen for complications and take a preventative/early management approach
- TPN associated liver disease
- Cause: Fatty liver, impaired liver function, and/or gallbladder/bile flow problems
- Diagnostic test: elevated liver enzymes
- Management: Avoidance of infections, optimize the use of oral/enteral nutrition, and/or changes in your TPN formula
- Chronic renal injury
- Cause: Usually from fluctuations in hydration or dehydration, kidney stones
- Diagnostic test: low glomerular filtration rate (GFR or eGFR), monitor your urine output periodically, want >1L urine/24 hours
- Management: Maintain adequate hydration and acid/base status which is managed through a combination of diet/lifestyle, medications, and changes in your TPN formula
- Central line infections
- Cause: Line infections can arise from difficulty in sterile technique, from an infection somewhere else in the body, or from movement of bacteria/fungi across the intestinal wall into the bloodstream
- Diagnostic test: blood cultures, taken from the line & also from a peripheral vein (skin poke)
- Management: Meticulous central line care, prompt management of infections with antibiotics, may require antibiotic or ethanol treatment of line
- Central line blood clots and IV access