Total Parenteral Nutrition (TPN)
Total parenteral nutrition (TPN) is a liquid form of calories and nutrients given into a large vein. TPN has been a life-saving option for patients who developed short bowel syndrome and intestinal failure. TPN was invented in the late 1960’s and prior to the invention, all patients with short bowel syndrome died of malnutrition. After years of formulation and experience, TPN is a safe and effective way to provide life-sustaining nutrients to patients who cannot absorb these calories and nutrients from the gastrointestinal tract. Specialized teams of medical professionals including doctors, nurses and pharmacists work closely with patients on TPN to ensure all caloric, fluid, and electrolyte needs are met in the safest manner.
There are limitations associated with TPN. First, the patient must have long-term central venous access. Most often, this is provided through a surgically placed catheter also known as a central venous catheter (CVC). The catheter is placed into one of the large veins in the chest. These catheters require special care to prevent problems. Secondly, the patient needs to have special equipment and supplies for administration of the TPN. Thirdly, specialized medical care and monitoring is required to make sure the TPN administration is safe.
There are also risks associated with TPN. The risks of complications vary from patient to patient and cannot be predicted. Some of these complications can be life-threatening and require immediate medical attention. The major complications are liver disease, central venous catheter (CVC) infections, loss of CVC sites and major fluid and electrolyte imbalances. Even with the limitations and risks, 80% or more of all patients on TPN do well with few or no complications.
The risks of liver disease, CVC infections and fluid & electrolyte imbalances are explained in detail below:
1. Liver disease can be associated with the administration of TPN. The cause of liver disease is unknown. Some patients, particularly the very young patient appears to be more likely to develop liver disease. It can occur any time after the start of TPN therapy. While the causes are unknown, there are several theories as to why patients may develop liver disease. One theory is that the nutrients are delivered to the body first and not to the intestine and liver. This in some way alters the liver reaction to the nutrients leading to disease. A few other theories include a loss of beneficial hormones given to the liver when nutrients are delivered through the gastrointestinal tract, possibly there are increases in bacteria that reach the liver when nutrients are delivered through TPN, or that there is altered blood flow to the liver related to the short bowel syndrome. In truth, the cause may be unique to each patient and may represent a combination of event. If patients develop progressive liver disease on TPN and cannot come off of TPN (that is, their intestine does not adapt), then they may develop end-stage liver disease or cirrhosis. This condition is very severe and will result in death without transplantation.
2. Vascular access complications are the next most common complication associated with TPN therapy. Multiple, recurrent infections of the central venous catheter can result in removal of the central venous catheter and can lead to severe, life-threatening infections. Doctors become very concerned when patients must have several central venous catheters removed due to infection, have infections with germs that are resistant to antibiotics, have infections with yeast, or have infections that are life-threatening. For unknown reasons, some patients appear more susceptible to these infections than others. In addition, a huge concern is the loss of central venous access sites. Adults generally have 6-8 standard venous access sites and children have 4-6 standard central venous access sites. When patient clot veins so that a catheter cannot be replaced in that vein, it is considered permanently lost. If a patient has more than half of their potential access sites removed, the medical team will become concerned over the long-term ability to maintain catheters to deliver TPN.
There are other significant complications that can be associated with TPN therapy. Patients can become dehydrated or develop renal failure. Patients may require a lot of medical care and frequent hospitalizations. Furthermore, the risk of death is slightly higher for patients on TPN than that of the general populations. The outcomes for an individual patient cannot be predicted.
Intestinal Transplant Links and Downloads
What is the Intestine: Introduction to Intestinal Transplantation
The United Network for Organ Sharing (UNOS) provides a toll-free patient services lines to help transplant candidates, recipients, and family members understand organ allocation practices and transplantation data. You may also call this number to discuss problems you may be experiencing with your transplant center or the transplantation system in general. The toll-free patient services line number is 1-888-894-6361
