Mark Nelligan Generic LOBs Flashcards
Organs that are commonly donated
Kidneys
Eyes (cornea)
Heart
Lungs
Liver
Pancreas
Skin
Solutions for organ shortages?
- Opt-in system-People must actively join register
- Opt-out system (“presumed consent”) -
People must actively get removed from register - Mandated choice -People are forced to make a decision
- Mandatory (deceased or live) donation - Everyone must donate organs
- Payments - Establish a free/regulated market in organ sales
Reasons for organ shortage?
Family consent, and negative
attitude contribute towards
organ shortage.
This could be due to the following reasons - 1. Religion 2 Fear, ignorance and misunderstanding 3. Legal aspects 4. Media reports on scandals involving organ rackets
How to improve organ donation
- Supporting organization for
networking and registry
maintenance - Effective use of technology to
facilitate organ donation
Contraindications to renal transplant
ABO incompatibility (relative)
Cytoxic antibodies against HLA antigens of donor.
Recent or metastatic malignancy.
Active infection.
HIV positivity ( relative)
Severe extrarenal disease (cardiac, pulmonary, hepatic).
Active vasculitis or glomeulonephritis.
Uncorrectable lower urinary tract disease.
Noncompliance.
Psychiatric illness including alcoholism and drug addiction.
Morbid obesity.
Age > 70 years.
Primary oxalosis.
Persistent coagulation disorder.
Comparison of survival rates in dialysis and transplant
Annual mortality rates for patients under dialysis
range from 21%-25%, but <8% with cadaveric and
<4% with living-related transplant recipients.
Healthier patients generally are selected for
transplantation.
The benefit of transplantation is most notable in
young people and in those with diabetes mellitus.
Criteria for living donor selection
Highly motivated.
ABO blood group-compatible.
HLA-identical or haploidentical
with negative cross-match.
Excellent medical condition with
normal renal function.
CRITERIA FOR CADAVER
DONOR SELECTION
Irreversible brain damage.
Normal renal function appropriate for age.
No evidence of preexisting renal disease.
No evidence of transmissible diseases.
ABO blood group-compatible.
Negative cross-match.
Best HLA match possible, particularly at the
DR and B loci.
Principles Involved In evaluating A
Prospective Living Kidney Donor
Whether there is a medical condition that
will put donor at increased risk for
complications for general anaesthesia or
surgery.
Whether the removal of one kidney will
increase the donor’s risk for developing
renal insufficiency.
Evaluation of kidney Fx in potential kidney donor
Serum creatinine.
Creatinine clearance.
Radionuclide glomerular filtration rate.
Urine analysis.
Urine Culture.
GFR > 70 ml/min.
Medical Conditions that exclude living kidney donation
Renal parenchymal disease.
Conditions that may predispose to renal disease
- History of stone disease
- History of frequent UTI
- Hypertension
- Diabetes Mellitus
Conditions that increase the risks of anaesthesia
and surgery.
Recent malignancy.
Does donation of kidney pose LT risk for donor
- increase GFR in remaining kidney so slight risk of proteinuria and HTN
- Metaanalysis confirmed >20yr safety after kidney donation
Components of matching between recipient and donor
A- Tissue typing
Determined by 6 antigens located on cell surface
encoded for by the HLA gene located on the short
arm of chromosome 6.
- Class I antigens (HLA-A and HLA-B) are expressed
on the surface of most nucleated cells.
- Class II antigen (HLA-DR) are expressed on surface
of APC and activated lymphocytes.
- These 6 antigens are referred to as major transplant
antigens.
- The match between donor and recipient can range
from 0 to six.
B- Cross matching
- A laboratory test that determines whether a potential
transplant recipient has preformed antibodies against the HLA
antigens of the potential donor. (Donor Lymphocytes +
Recipient Serum) - A Final CM is mandatory
C- Compatible ABO blood group.
Factors affecting longevity of renal allograft
Age
HLA matching
Delayed graft function
Ischemia time.
Number of acute rejection
episodes.
Native kidney disease.
Ethnicity.
Others
LT Complications of allograft
- Chronic rejecction
2, Death with fx graft
Risks associated with chronic immunosuppression
1- Malignancy
2- Infection
3- Side effects of different drugs
(steroids, CsA, tacrolimus, MMF, …..)
Living donor steps
- Meeting of potential recipient and donor w/ coordinator
- Initial blood tests
- Immunological tests
- Meeting w/ transplant nephrologist
- Meeting with transplant surgeon
- Discussion of case at weekly meeting and completion of examinations
Criteria and point allocation for
candidate selection from the waiting list
Time on the Waiting List
HLA typing matching
Recipient age
Difference in age between donor and
recipient
ABO blood compatibility
Extra points for children and sensitized
patients
What is paired donation
Potential donor A and potential recipient B are in a relationship (relation, friend or
partner) but are not genetically compatible. Potential donor C and potential
recipient D are in the same position. A is compatible with D and C is compatible
with B. Thus A gives to D and C gives to B
wHAT IS POOLED DONATION
Like paired but more than two pairs involved in swap
What is Non-directed donation v directed donation
Person offers to donate an organ to anyone who might benefit v person offers to donate an
organ to a specific person/group.
What is domino organ donation
When an organ is removed for the primary purpose of that person’s medical treatment, but
then used for transplant into another person
Is it unethical for a doctor to encourage pts. to be living donor
YES - it is unethical for a doctor to encourage his/her pt.
1.‘First do no harm’ primum nil nocere
- ‘Doctors have a secondary dutyto promote organ donation and transplantation as one way of promoting public health. But this secondary duty should not supersede
their primary duty - Act in best interests of patients and respect their autonomy
Doctor asking may be seen as coercion due to the power imbalance in doctor/pt. relationship…… valid consent consequences may
ensue
NO - it is not unethical …..
A good thing? A noble thing? Offering a gift - of life - Latin – ‘Donum’ -
gift & ‘Dare’ to give
‘If something is not wrong to do but is actually a good thing, then it
cannot be wrong to encourage the doing of it’
Demonstrates solidarity between humans
Who regulates organ transplants
NHS Blood and Transplant (NHSBT) : Special Health Authority SPA which is responsible for: efficient supply of
blood, organs and associated services to the NHS
Human Tissue Act 2004 : provides the legal framework for organ donation
The Human Tissue Authority:
aims to ensure that human tissue is used safely, ethically, and with proper
consent.
What does the human tissue act 2004 say about transplants?
- Makes consent the most important principle for
the lawful retention and use of human tissue - Established the Human Tissue Authority
- Makes it an offence to transplant organs unless the
regulations of the Act are adhered to. - Makes it an offence to be involved in the sale of
organs in any way
Living donations:
- HTA to approve all (related or not) including paired/pooled and altruistic
(directed or not) - HTA Independent Assessor (IA) to meet donors/recipients and to report to HTA.
- HTA Panel must consider special cases (e.g. children).
Deceased donation:
- No need for HTA approval.
- If patient has consented then consent is sufficient.
- If patient does NOT consent then no transplant
can go ahead - If patient has nominated a person to make the
decision then the nominee can give proxy consent - If patient has not expressed any wishes either way
people in ‘Qualifying Relationship’ can consent
Qualifying relationships
In the following order:
a) spouse or partner (inc. civil or same sex partner)
b) parent or child
c) brother or sister
d) grandparent or grandchild
e) niece or nephew
f) stepfather or stepmother
g) half-brother or half-sister and
h) friend of long standing.
When can you harvest an organ
Brain stem death BSD (Heart beating
donation)
- Donation after Circulatory Death DCD
Significance of brain death
Acceptance of brain death has done much to facilitate transplantation
Prior to acceptance of brain death, patients not dead until breathing &
circulation stopped
Death must be clearly pronounced, entered in record before transplantation is
discussed
Some have claimed that brain death is “too convenient” a definition of death
Donation after circulatory death
- Organ donation that takes place following diagnosis of death by
cardio-respiratory criteria, Code of Practice for Diagnosis and Confirmation of Death. - Form of donation known as non-heart beating donation (NHBD),
and donation after cardiac death (also shortened to DCD) in recent
times. - Donation after circulatory death may be controlled or
uncontrolled.
