Types of Liver Transplant
There are two types of liver transplant depending on the source of liver:
Deceased Donor (brain dead, cadaveric) Transplant
Brain death is sudden death after an accident, brain hemorrhage or stroke with irreversible brain damage, not compatible with life. Brain dead patients may be artificially maintained on a ventilator and supportive medicines for a short duration and may be able to donate their organs for transplantation, if their family desires. Donation by a single deceased donor can enable as many as nine lifesaving organ transplants and numerous life-enhancing tissue replacements.
Livers from deceased donors are matched with recipient’s blood group and size, offered to the first patient on the waiting list, and if suitable, transplanted. The whole liver is usually transplanted, although sometimes it may be divided into two portions and offered to two patients, generally a child and an adult. Unfortunately, the number of patients in need of a transplant far outnumber the availability of such organs; therefore, not all patients are able to undergo a deceased donor liver transplant.
Living Donor Transplant
Living donors can donate one of a paired organ such as a kidney or one lobe of the liver. Living donors are family members or close relatives of the patient. The diseased liver is replaced with a segment of liver from a healthy human donor (usually an immediate relative of the patient for example father, mother, sibling, spouse , children, grandfather, grandmother or grandchildren)
Living donor liver transplant is based on two remarkable qualities of the liver
Reserve: Even 25% of the liver can provide sufficient function for a person; therefore, one can easily tolerate removal of a large portion of the Liver.
Regeneration: liver has the capacity to regenerate / re-grow back to its normal size. The process starts soon after division / transplantation of the liver in both the donor and the patient. About 90 – 100% of regeneration happens within 2-3 months.
Because of these properties, 50 – 70% of normal liver can be safely removed and the remaining liver provides adequate function until complete regeneration. A margin of safety is always kept for the donor when planning the transplant. Generally, patients need a liver which is 0.8 - 1% of their body weight to recover well from the operation, which commonly corresponds to a right lobe for an adult patient, left lobe for an adolescent and left lateral segment for a small child.
In India, more than 80% of transplants are from living donors that is in contrast with western countries where more than 90% of transplants are by deceased donors’ livers.
Living donor liver transplant is technically more complex than deceased donor liver transplantation, but can be safely performed at experienced and established institutes.
A few advantages of living donor transplants are:
- Living donors are healthy people with a perfectly healthy liver, and go through a rigorous process of evaluation, therefore the chances of liver not working after transplantation is very minimal.
- Better genetic match between living donors and candidates may decrease the risk of organ rejection.
- It is an elective, planned operation allowing doctors to schedule the transplant at an optimum time, this is especially important for patients who are very sick and need stabilization before surgery.
- It also allows doctors to perform an emergency transplant for patients with acute liver failure as a life-saving measure.
- Patients with liver tumors carry the risk of tumor spread while waiting for a deceased donor liver transplant and might benefit from an early living donor liver transplant.
- Donation is a positive experience and most donors experience a sense of heroism in being able to save (in case of liver transplantation) or dramatically change (in case of kidney transplantation) the recipient’s life.