While intestinal failure can oftentimes be treated with alternative therapies such as parenteral nutrition (PN), complications such as PN-associated liver disease and short bowel syndrome may make transplantation the only viable option.

For the next two decades, attempts at transplanting the small intestine in humans were met with universal failure, and patients died of technical complications, sepsis, or graft rejection.

Causes of intestinal failure may be clinically complex, and may result from a combination of nutritional, infectious, traumatic, and metabolic complications that affect ordinary anatomy and physiology.

[8] Surgical removal is the most common cause, performed as a treatment for various gastroenterological and congenital conditions such as Crohn's disease, necrotizing enterocolitis, mesenteric ischemia, motility disorder, omphalocele/gastroschisis, tumors, and volvulus.

Long-term survival with SBS and without PN is possible with enteral nutrition, but this is inadequate for many patients as it depends on the remaining intestine's ability to adapt and increase its absorptive capacity.

[5][10] Over long periods of time, PN can lead to numerous health conditions, including severe dehydration, catheter-related infections, and liver disease.

[8][13] There are four Medicare and Medicaid-approved indications for intestine transplantation: a loss of two of the six major routes of venous access, multiple episodes of catheter-associated life-threatening sepsis, fluid and electrolyte abnormalities in the face of maximal medical therapy, and PN-associated liver disease.

Early referral requires trust between all parties involved in the operation to ensure that a rush to judgment does not lead to a premature transplant.

Multivisceral grafts are considered when the underlying condition significantly compromises other sections of the digestive system, such as intra-abdominal tumors that have not yet metastasized, extensive venous thrombosis or arterial ischemia of the mesentery, and motility syndromes.

If appropriately managed, the continuation of blood flow and bodily metabolism allows for healthier organs for procurement and additional time to prepare recipients for transplant.

[22] When determining potential donor-recipient matches, important characteristics include donor size, age, tissue quality, and ABO and histo-compatibility.

Ideally, intestines should be selected from donors of lighter weight than the proposed recipients to ensure simple closure of the abdominal wound.

Through T-cell receptors, T-lymphocytes are able to distinguish between self and non-self by recognizing human leukocyte antigens (HLA) bound to the major histocompatibility complex (MHC) protein located on the surface of organ cells.

[2] ABO-incompatible grafts can sometimes be performed on very young pediatric patients, as their immune systems have not fully developed and for whom waiting list mortality remains high.

Even with healthy physiological levels, ABO and HLA compatibilities, and no signs of bacterial, viral, and fungal infections, organ transplantation is not without extrasurgical risk.

Therefore, ensuring cardiac survival and nearby donor-recipient proximity before procurement are essential so organs do not wait too long outside the body and without blood flow.

[18] They may also be treated with anti-lymphocyte antibodies (anti-thymocyte globulin, alemtuzumab), irradiation directed against excessive mesenteric lymphatic tissue, and have their bowel irrigated.

The team exposes the abdominal cavity and inserts two cannulae for the infusion of University of Wisconsin organ preservation solution into the aorta and inferior mesenteric vein.

[17] The graft is then reperfused with blood and any bleeding is stopped before the proximal and distal ends of the transplant bowel are connected to the original digestive tract.

[18] Preservation of the native spleen, pancreas, and duodenum during a multivisceral transplant can reduce the risk of additional complications related to these structures.

Next, various assortments of interleukin-2 (IL-2) receptor antagonists (daclizumab, basiliximab), anti-proliferation agents (azathioprine, mycophenolate mofetil), and the drugs cyclophosphamide and sirolimus are administered on an individual patient basis to further suppress the immune system.

[2] Intravenous administration of prostaglandin E1 is occasionally performed for the first 5 to 10 days following transplant to improve intestinal circulation and a potential dispensing of immunosuppressive effects.

[14] Evidence for the restoration of function includes decreasing gastrostomy tube returns and increasing gas and enteric contents in the ileostomy.

[2] Routine surveillance endoscopy and biopsies via the ileostomy should be performed with decreasing frequency over several months to observe signs of rejection, ideally before clinical symptoms present themselves.

Because of exposure to a wide range of gut flora and material consumed by the body, the intestinal epithelium possesses a highly developed innate immune system and antigen-presenting abilities.

Immunosuppression is the primary determinant of outcome in small bowel transplantation; the risk for graft rejection is increased by under-immunosuppression and for local and systemic infection with over-immunosuppression.

[14] Intestinal transplants are highly susceptible to infection even more so than the standard immunocompromised recipient of other organs due to the great composition and variety of the gut flora.

[9][15] Furthermore, underlying etiology,[29] the presence of comorbidity, the frequency of previous surgery, nutritional status, and the level of liver function have been found to affect patient-graft survival .

The low quality of life induced by intestinal failure is oftentimes further supplemented by significant psychosocial disability and narcotic dependence.

Total charges to maintain PN at home can reach upwards of $150,000 a year, even though the actual cost of nutrition is typically only $18 to $22 a day.