How can you be sure that someone who is brain dead cannot feel pain? And why does a donor actually receive anesthesia when the organs are removed?
Michael Kuiper, neurologist-intensivist at the MC Leeuwarden explains.
No pain?
‘How can you be 100 percent sure that someone no longer feels anything when the organs are removed?’
To feel at all, the brain stem must still be active. That is the central conduit for all incentives. When you burn your hand, the brainstem causes you to signal the pain. In people who have been declared brain dead, the brain stem is by definition irreparably destroyed. That’s why we know for sure that the brain-dead donor no longer feels anything. The brain death protocol that applies in the Netherlands is very strict and the legally required only way to determine brain death. So someone can never be declared brain dead without going through the brain death protocol. Multiple physicians are always involved in performing the brain death protocol. In this way, no mistakes are possible and we can say with certainty that the brain is so damaged that no pain can be felt anymore.
Why anesthesia?
‘Why does someone who is brain dead receive anesthesia during the operation to remove the organs? Isn’t that necessary if you can’t feel pain anymore?’
“Narcosis consists of three components: muscle relaxation, pain relief and sleep medication.
During a donor operation, muscle relaxants are always administered for two reasons: 1) to relax the abdominal wall so that the surgeon can reach it and 2) to suppress so-called ‘spinal reflexes’. Spinal reflexes are reflexes that also occur in people who are alive, such as the patellar reflex: the tap with the doctor’s hammer that causes your lower leg to shoot up. The reflex loop goes from the sensory nerve in the leg via the spinal cord directly back to the movement nerve of the leg. This movement is therefore not caused by the brain. The brain can counteract this reflex (that is why the patellar tendon reflex is not present in many people if they do their best). In a brain-dead donor, spinal reflexes are not stopped by the brain and can therefore be present. Direct stimulation of a sensory nerve can therefore also lead to movement of the legs in the case of brain death.
The other components of the anesthesia (pain relief and sleep medication) are usually also administered, but for a different purpose than with a ‘normal’ operation.
Pain relief is administered to suppress automatic, involuntary responses of the body. The moment a body is cut in which the blood circulation is artificially kept going, the immune system is activated. This means that, for example, the heart rate may increase, or the blood pressure may rise. These are processes that run through the spinal cord and therefore happen outside the brain. The spinal cord still functions, because there is still an artificially maintained blood circulation. Pain relief is sometimes administered to dampen the automatic reactions. So NOT because the donor can still feel pain (after all, pain experience takes place in the brain, which is irreparably damaged), but to keep the organs in the best possible condition.
A sedative is sometimes administered during the operation, not to put the donor to sleep as with a ‘normal’ operation (after all, there is no consciousness anymore, the brain is irreparably damaged), but because a side effect of the sedative is that the dilate blood vessels. Should the blood pressure rise during the operation, the anesthetist will administer sedatives in vapor form, which will lower the blood pressure.”
There are many misconceptions about brain death in organ donation. Intensive care doctor Jelle Epker listed the most important facts.
