It is very important to consider the pros and cons of transplantation for each patient on an individual basis. Patients who are doing well on intravenous feeding (Parenteral Nutrition: PN) have a very good life expectancy (see fig 1) and can live with a very good quality of life.
One of the most important aspects of life on PN is to be trained to use it properly.
There are two main intestinal failure centres in the UK (St Mark’s and the Hope hospital, Salford) which have excellence in PN management and training. There are also several other specialist units in the UK that manage PN to a very high standard.
However, survival following intestinal transplantation is not as good, although patients are usually free from PN and for some this can improve their quality of life, those patients who are doing well on PN will not notice a great deal of improvement in QOL, they might swap PN for other problems associated with the transplantation procedure and their life expectancy is not nearly as good (fig 1). Therefore, intestinal transplantation should only be used for patients who are not doing well on PN.
Some will develop PN related liver disease such that they can not continue PN; others will thrombose the veins used to give PN which eventually will make it impossible to administer PN. As these complications arise in a small group of patients it is important to make the decision whether or not they should be put forward for transplantation. If put forward too late when they have multiple complications and are in poor condition they are less likely to survive the procedure. The timing of the transplantation is therefore critical and this needs to consider a host of factors which can vary widely between patients.
In order to make the best decision possible all UK patients are reviewed in a national meeting called the National Adult Small Intestinal Transplantation forum (NASIT forum). This was founded in 1990 by Drs Simon Gabe (St Mark’s hospital, London) and Stephen Middleton (Cambridge University teaching hospital).
Therefore in general, intestinal transplantation is indicated in patients with intestinal failure who are failing on parenteral nutrition. The term failing on parenteral nutrition generally implies the development of frequent, severe or life threatening complications. The following list is derived from the approved Medicare indications and has been approved by the American Gastroenterology Association (AGA).
1. Impending or overt liver failure due to PN induced liver injury
The clinical manifestations include elevated serum bilirubin and/or liver enzymes, splenomegaly, thrombocytopenia, gastro-oesophageal varices, coagulopathy, stomal bleeding or hepatic fibrosis/cirrhosis.
2. Thrombosis of 2 or more major central veins
This is considered a life threatening complication and failure of PN therapy.
3. Frequent central venous catheter infection & sepsis
The development of two or more episodes of systemic sepsis secondary to line infection per year that requires hospitalization indicates failure of PN therapy. A single episode of line related fungaemia, septic shock and/or acute respiratory disease syndrome (ARDS) are considered indicators of PN failure. Patients should be reviewed by one of the primary intestinal failure centres to further evaluate the reasons for recurrent sepsis before consideration for transplantation.
4. Frequent severe dehydration despite IV fluid supplement in addition to PN
The UK indication guidelines also include patients who need removal of many organs. This might be necessary in order to excise benign tumours for conditions such as desmoid disease. Widespread mesenteric vascular disease of a critical degree might also be considered as an indication especially if there has already been an ischaemic event leading to intestinal failure.
5. Quality of life.
Patients who experience very poor quality of life on PN may wish to consider transplantation. However, careful consideration is needed as transplantation may not necessarily correct the factors causing poor quality of life. Transplantation does not put patients back to normal and does give them ongoing problems to deal with including taking life long medication, being more prone to infections, the need for regular visits to hospital for check ups, often a permanent stoma (ileostomy) is required and obtaining employment is usually much more difficult after a transplantation.
Furthermore, patients on PN who have not had any major complications are likely to live a lot longer than if they had transplantation. A general comparative survival would be 90% survival at 10 years on PN compared to 45% 10 year survival after transplantation. It should also be remembered that the technique of transplantation is improving and if patients wait their chances of long term survival may improve as we get better at transplantation, assuming that their medical condition does not deteriorate, but this of course can be closely monitored.