How is a person assessed as a donor for living related transplant?
The potential donor has to undergo very thorough and vigorous
investigations to make sure that both his kidneys are healthy. If there is
even the slightest doubt about his kidney it will not be taken from him.
He must be in good health and have no history of kidney disease,
hypertension, diabetes mellitus, cancer or any other disease. He will be
assessed psychologically and mentally to ensure that he fully comprehends the nature of the donation, that there are no social pressures on
him to donate and that he is donating voluntarily out of love and
consideration for the patient. He will undergo a thorough physical
examination. The urine and blood tests performed on him must be
normal. There must be no protein or blood in the urine. One of the
tests involves the collection of a 24-hour urine sample.
The ABO blood group between the donor and the recipient must be
compatible. The HLA tissue typing must have at least a 50% match
( one haplotype match ).
If the above tests are satisfactory the prospective donor will have to
undergo a special X-ray examination to find out if there is any
abnormality in the kidneys. This test is called a renal arteriogram. If it
is satisfactory, then the donor is considered suitable for a kidney
donation and a date for the transplant operation will be scheduled.
Who are the potential cadaver kidney donors?
Donors should not be patients suffering from cancer as cancer may
invade the kidney and be carried over to the recipient. The donor
should not suffer from any infection as it can be transmitted to the
recipient. The cadaver donor should also be not more than 60 years of
age. Most donors were patients who had sustained head injuries from
road traffic or other accidents. Sometimes a bleed in the brain from
various causes can also result in brain death, qualifying the person as a
suitable cadaver donor.
The potential donor is therefore someone who has had an accident or
damage to the brain with no possibility of recovery and has to be
maintained on a respirator. It is important that the potential donor be
placed on a respirator as it pumps oxygen into the donor's lungs and keep the heart beating and blood flowing to the kidneys for normal
functioning even though his brain is already dead ( brain death ).
What is meant by brain death?
When a person dies, it means that his brain has ceased to function.
The medical term for this is brain death. The beating of the heart and
respiration can be taken over by machines but it does not mean that the
dead person is still alive. If the machines are turned off, the heart and
respiration will stop because the dead brain is incapable of supporting
By testing certain functions of the brain and noting their absence, a
doctor can pronounce that a person is dead.
The heart can still be beating as the heart muscles can continue to
beat for some time after brain death. For the purpose of kidney
transplant, it is important that the cadaver donor's heart is still beating
for blood to continue circulating into the kidneys to keep them
functioning and producing urine. If the heart stops beating for more
than an hour, the kidneys, deprived of blood, would be irreparably
damaged and be of no use at all in a kidney transplant. This explains
why kidneys for transplant must be removed during the time when the
person is brain dead rather than wait till the heart stops beating.
What is the Opting Out Law?
In most countries most of the transplanted kidneys are from cadaver
donors but in Singapore most of our transplanted kidneys come from
living related donors. There is sadly a lack of cadaver donors because
relatives have refused to give consent for kidney donation for various
cultural and other reasons. These kidneys which are buried or cremated
actually go to waste because they could be used to save the lives of a
hundred people a year who die needlessly because they are unable to get
cadaver kidney transplants. It is a tragedy as the majority are young,
aged between 30 and 40. Many are married and are fathers or mothers
of very young children. Many are also sole bread winners at the peak of
their lives. Most are too poor to be able to seek private dialysis. In many
overseas countries they go on to the state-supported dialysis programme
and within weeks, receive a cadaver transplant which accounts for 90%
of the total transplants done there. In Singapore there are 3 state-supported dialysis centres with about 160 places but since these people
cannot undergo transplants because of lack of cadaver kidneys there is
no turnover of dialysis places. There are no vacancies in these centres
for patients and because of their very small family income they cannot
afford to seek private dialysis. As a result most die and only about 20 to
30% of the 200 new patients with end-stage renal failure are saved each
year. Most of those who are saved were fortunate to have living related
transplants from a parent or sibling. The majority die due to a lack of
The government has studied this problem and has come out with a
solution. In 1986, 128 people died from road traffic accidents. To save
100 patients with kidney failure only 50 brain dead cadavers are
required because each cadaver has 2 kidneys and a patient with kidney
failure needs only one kidney to survive. A law called the Human
Organ Transplant Act was passed on 16th July 1987 and implemented
in January 1988. The Act allows for the removal of kidneys from
Singaporeans and Permanent Residents who die from accidents for the
purpose of transplant to kidney failure patients, unless they have
specifically objected to this in their lifetime. In some countries like
France, Austria, Israel and Belgium where this Act is practised, many
patients who suffer from kidney failure have been saved.