3. Transplantation Flashcards
(50 cards)
When is a ‘life enhancing’ transplantation done?
Occur in organs where other-life support methods aren’t as good e.g. dialysis
Why do the following organs fail: • Cornea • Skin • Bone marrow • Kidney • Liver • Heart • Lungs • Pancreas • Small bowel
- Cornea - degenerative disease, infection, trauma
- Skin - burn, trauma, tumour
- Bone marrow - tumour, hereditary disease
- Kidney - diabetes, HT, glomerulonephritis
- Liver - cirrhosis
- Heart - CAD, cardiomyopathy, congenital defects
- Lungs - COPD, CF, pulmonary HT
- Pancreas - T1DM
- Small bowel - hereditary conditions or related to prematurity
What is an autograft?
Transplantation within the same individual
What is an isograft?
Transplantation between genetically identical individuals of the same species
What is an allograft?
Transplantation between different individuals of the same species
What is an xenograft?
Transplantation between different species (e.g. heart valves and surgical skin plasters)
What is a prosthetic graft?
Using plastic or metal
Give examples of future autograft surgery
- Using stem cells to make full organs
- At the moment they can be transferred into various cell lineages - hard to organise them into 3D structures
- Can use scaffolds to form 3D structures
Give examples of the following types of allografts: • Free cells • Temporary • Privileged sites • Framework • Composite
- Free cells - bone marrow, pancreas islets
- Temporary - blood
- Privileged sites - cornea
- Framework - cartilage, nerves
- Composite - hands, face, larynx
What is a composite graft?
A graft involving several tissues e.g. face transplant involve skeletal muscle, skin and blood vessels
What is an orthotopic and heterotopic transplant?
- Orthotopic - organ placed where it should be e.g. liver
* Heterotopic - organs placed elsewhere in the body e.g. kidneys and pancreas
Where are transplanted kidneys often placed?
- In the iliac fossa
* Attached to the iliac vessels
What is the pancreas plumbed onto and transplanted with?
- Plumbed onto the iliac arteries
* Transplanted with a segment of bowel
What type of organ can be transplanted from a living donor?
- Bone marrow
- Kidney
- Liver
Describe the 2 main types of deceased donation
- DBD (donor after brain death) - need to confirm brain death, mainly road accident and cerebral haemorrhage, harvest organs and cool
- DCD (donor after cardiac death) - suitable for kidney transplant, long period of warm ischaemia time can cause damage
What potentially reversible things can cause apnoeic coma?
- Depressant drugs
- Metabolic or endocrine disturbance
- Hypothermia
- Neuromuscular blockers
How can a lack of brain stem function be demonstrated?
- Pupils both fixed to light
- Corneal reflex absent
- No eye movements with cold caloric test
- No cranial nerve motor responses
- No gag reflex
- No respiratory movements on disconnection (with PaCO2 > 50 mmHg)
What has to be excluded before using a DBD/DCD patient before transplantation?
- Viral infection e.g. HIV, HBV
- Malignancy
- Drug abuse
- Overdose
- Poison
- Disease of the organ to be transplanted
What is the absolute maximum and ideal cold ischaemia time for the kidney?
60 hours (ideally <24h)
What does transplant selection and allocation refer to?
- Selection - access to waiting list
* Allocation - access to organ
What are the contraindications to being placed on the transplant selection list?
- Too early - still has some organ function
- Co-morbidity - medical, psychiatric, surgical e.g. CV disease, malignancy, compliance
- Patient does not want a transplant
What is considered in transplant allocation?
Equity
• What is fair?
• Time on waiting list
• Urgent? imminent death
Efficiency
• What is the best use for the organ in terms of survival
What does it mean by kidney transplants being highly sensitised?
Likely to develop rejection if they receive a transplant
How many tiers are there in kidney allocation and what do they depend on?
- 5 tiers
* Depends on age and sensitivity
