Donation after death
Death must have occurred before donation can take place.
Death can be determined to have occurred in two ways:
- Brain death occurs when there is irreversible cessation of function of the brain.
- Circulatory death occurs when there is irreversible circulation of blood in the body of the person.
It is important to understand the difference between brain death and circulatory death. The way a person dies influences how the donation process occurs and which organs and tissues can be donated.
The below information is to support you and your family to make a decision about donation that is right for you and your loved one.
Understanding brain death
Brain death occurs when the brain has been so badly damaged that it completely and permanently stops functioning. This can occur as the result of severe head injury, a stroke from bleeding (haemorrhage) or blockage of blood flow in the brain, brain infection or tumour, or following a period of prolonged lack of oxygen to the brain.
Just like any other part of the body, when the brain is injured, it swells. The brain is contained within a rigid 'box', the skull, which normally protects it from harm but also limits how much the brain can expand and swell after an injury. This is different to other parts of the body, such as an injured ankle, that can continue to swell without restriction. If the brain continues to swell, pressure builds up within the skull causing permanently damaging effects.
The swelling places pressure on the brainstem, where the brain joins with the spinal cord at the back of the neck. The brainstem controls many functions that are necessary for life including breathing, heart rate, blood pressure and body temperature.
As the brain swelling increases, the pressure inside the skull increases to the point that blood is unable to flow to the brain (see Diagram 1). Without blood and oxygen, brain cells die. Unlike many other cells in the body, brain cells cannot re-grow or recover. If the brain dies, that person's brain will never ever function again, and the person has died. This is called 'brain death'.
The brain and brainstem control many of the body's vital functions, including breathing. When a person has suffered a brain injury, they are connected to a machine called a ventilator, which artificially circulates oxygen into the lungs (ventilation). The oxygen is then pumped around the body by the heart. The heartbeat does not rely on the brain, but is controlled by a natural pacemaker in the heart that functions when it is receiving oxygen.
While a ventilator is providing oxygen to the body, the person's chest will continue to rise and fall giving them the appearance of breathing, their heart will continue to beat and they will feel warm to touch. This can make it difficult to accept that brain death has occurred. However, even with continued artificial ventilation, the heart will eventually deteriorate and stop functioning.
How do doctors know that a person's brain has died?
People who are critically ill in hospital are under constant observation by the specialist medical and nursing teams caring for them and are closely monitored for changes in their condition. There are a number of physical changes that take place when the brain dies. These include loss of the normal constriction of the pupils to light, ability to cough, inability to breathe without the ventilator, and reduced blood pressure and body temperature.
When the medical team observes these changes they will perform clinical brain death testing to confirm whether the brain has stopped functioning or not.
Two senior doctors will independently conduct the same set of clinical tests at the bedside. The doctors performing the brain death testing will be looking to see if the person has any:
- response to a painful stimulus;
- pupil constriction when a bright is shone in the eye;
- blinking response when the eye is touched;
- eye movement when ice cold water is put into the ear canal;
- gag reaction when the back of the throat is touched;
- cough when a suction tube is put down the breathing tube; and
- ability to breathe when the ventilator is temporarily disconnected.
If a person shows no response to these tests, it means that their brain has stopped functioning and the person has died. Although they have died the heart will still be beating because oxygen is still getting to the heart with the assistance of the ventilator.
There are times when the person's injury or illness means that clinical brain death testing cannot be done. For example, facial injuries may limit examination of the eyes or ears. In these circumstances, medical imaging tests are done to determine if there is any blood flow to the brain. The hospital staff will provide further information if such a test is necessary.
What happens after brain death has been confirmed?
Once brain death has been confirmed, the person will remain connected to the ventilator while members of the healthcare team speak with the person's family about the next steps. These will include the person's end-of-life wishes, the opportunity for organ and tissue donation and timing of removing the ventilator.
If the family supports donation, everything possible will be done to make sure those wishes are fulfilled. Timeframes can vary as every circumstance is different. It can take an extended period of time for necessary arrangements for donation to be made. The person will remain connected to the ventilator and medications provided to support the blood pressure and keep oxygen circulating to the organs. Increased medical activity may be seen around the person, due to the need for further tests. If it becomes clear that organs are not suitable for donation, the senior next of kin will be notified and it may still be possible for the doncation of tissue including eye, heart, bone and skin to occur.
When the arrangements for donation have been made, the person will be transferred to the operating theatre for the organ and tissue retrieval surgery. The ventilator will be removed during the operation.
If donation is not supported, the doctor will speak with the family about removing the ventilator. When the ventilator is removed, the person's heart will stop beating due to a lack of oxygen, and their skin will become cold and pale because blood is no longer being circulated around the body.
Care, dignity and respect are always maintained during end of life care, whether or not donation proceeds.
Understanding circulatory death
Circulatory death occurs when a person stops breathing and their heart stops beating (there is no blood flow in the body). This can occur after a sudden illness or accident, or can be the final stage of a long illness.
Organ donation is sometimes possible after circulatory death although only in particular situations, as organs quickly deteriorate once blood flow to them stops. The usual circumstance is when a person is in an intensive care unit following a severe illness from which they cannot recover and the doctors and family agree it is in the person's best interests to remove artificial ventilation and any other life supports. This may occur when a very severe brain injury resulting in a permanent severe disability, people with terminal heart or lung failure, or people who have suffered a very severe spinal injury where they cannot move or breathe unassisted.
The priority is then to support the person with care, comfort and compassion at the end of their life. The withdrawal of life support is always discussed with and agreed by the family (and patient if possible). Only when this decision has been made, is there any consideration of donation.
What happens after the doctors believe the patient's heart is going to stop beating?
When the family and the doctors have agreed that continuing treatment is not in the person's best interest, they will speak with the person's family about the next steps. This will include discussion on the person's end-of-life wishes and removal of the ventilator and other treatments, with a focus on providing comfort and pain relief.
If the doctors expect that the person will stop breathing and circulatory death will occur within 90 minutes after taking away the ventilator and any other life supports, there may be the opportunity for organ and tissue donation to occur.
If the person and family supports donation, everything possible will be done to make sure those wishes are fulfilled. It can be very difficult to predict the exact time it will take for a person to die following removal of the ventilator and other life supports. Some patients die within an hour or so, and donation may be possible. Others may not die until many hours later. If this occurs, organ donation will no longer be possible but donation of tissues may still be possible. If death does occur soon after removing life supports, the person will need to be moved quickly to the operating theatre so that the organ retreival surgery can occur before the organs become damaged.
If donation is not supported by the family, the doctor will speak with the family about removing the ventilator. When the ventilator is removed, the person's heart will stop beating due to a lack of oxygen, and their skin will become cold and pale because blood is no longer being circulated around the body.
Care, dignity and respect are always maintained during end of life care, irrespective of whether or not donation proceeds.