Death and organ donation Flashcards
Why are kidney donations from cadavers so much larger than from living donors?
Can take both kidneys from cadaveric donors
Double the amount of transplants since can only take one kidney from a living donor
What is the trend in the amount of living donors over the years?
Increased
Due to transplantation between family members/ friends/ altruistic donors
What is the trend in the amount of dead donors over the years?
Donors that have undergone cardiac death have increased
Donors that have undergone brain death have remained stable
What are the two types of donors?
Living donors
Deceased donors
What are the two types deceased donors?
Those that died following brain death - heart beating
Those that died following cardiac death - non-heart beating
What are examples of living donors?
Friends
Relatives
Altruistic
What are the two types of deceased donors?
Those that died following brain death
Those that died following cardiac death
What are causes of brain death?
Stroke
Tumours
Accidents
No longer able to maintain life
When are organs extracted from cardiac death donors?
Cardiac arrest
Predicted to die after withdrawal of therapy in the ICU
What is the definition of death?
Simultaneous and irreversible loss of both the capacity for consciousness and the capacity to breathe
What are the 3 main causes of death?
Neurological determination of death
Somatic determination of death
Cardio-respiratory determination of death
Why is brainstem death equal to death?
Brainstem is a very important organ for life
The effect of this organ failing is equivalent to death
What are the functions of brainstem?
Control of respiration
Integrative control of the cardiovascular system
Conduit for almost all ascending and descending neural pathways
Maintenance of the capacity for consciousness
When was the brainstem death criteria devised in the UK?
1976
What are examples of brainstem criteria?
Fixed pupils which do not respond to sharp charges in the in the intensity of incident light
No corneal reflex
No response to supraorbital pressure
No cough reflex to bronchial stimulation or gagging response to pharyngeal stimulation
Caloric test
Disconnection of the ventilator
How does disconnection of the ventilator act as a good test to check for brain death?
No observed respiratory effort in response to disconnection of the ventilator for long enough to ensure elevation of the arterial partial pressure of CO2 to at least 6.0 kPa
What is the caloric test?
Absent oculovestibular reflexes
No eye movements following the slow injection of at least 50 ml of ice-cold water into each ear in turn
What are the conditions needed to be followed to appropriately determine brain stem death?
Two independent physicians, not involved in transplant team - no bias
Exclude the confounding factors to appropriately determine brain stem death
What are confounding factors that could affect determination of brain stem death?
Drugs
Hypothermia
Metabolic conditions that could influence the action of the brainstem
What is the most common source of organ donation?
Brain dead donors
How are non-heart beating donors classified?
Maastricht classification
What is the Maastricht classification of non-heart beating donors?
Group I - brought in dead
Group II - unsuccesgul resuscitation
Group III - awaiting cardiac arrest
Group IV - cardiac arrest after having brainstem death
Group V - cardiac arrest in a hospital inpatient
What are groups I and II in the Maastricht classification called?
Uncontrolled
What is group III in the Maastricht classification called?
Controlled
