Understanding The Differences of Brain Injuries and Brain Death
For many people, it is their worst nightmare: their loved one has fallen victim to an injury or a stroke, and they are now lying in a coma, suffering from a brain injury. It can be difficult to tell when they will wake up, or if they will at all.
It can help to know that there are many degrees of comas and coma-like conditions, ranging from an initial presentation of brain injury symptoms, only lasting a couple of weeks, to a worst-case-scenario of brain death. Here is a brief rundown of some of the better-known states of brain injury:
- Coma: this is often the initial presentation of a severe brain injury. It is a state in which the patient appears to be asleep with eyes closed, but cannot be awakened. This may or may not involve involuntary movement – in many cases, the patient may not react in any way, even to something that would otherwise be painful. Quite often, this only lasts a couple of weeks, and the patient will come out of it on their own. In cases where it lasts longer, it can develop into something more serious.
- Vegetative state: this is very similar to a coma, but the patient’s eyes can be open. The patient will also tend to display some non-conscious reaction to pain, such as increased heart rate and sweating. However, while the eyes may be open, the cognitive and higher brain functions have not been restored, and there is no conscious interaction with the environment. The vegetative state becomes persistent if it has lasted longer than one month. How long it takes to be considered permanent depends on the cause of the initial injury. In cases where the brain damage was caused by trauma, the vegetative state is considered permanent after 12 months. In cases where the damage was caused by oxygen deprivation, such as a heart attack or drowning, it takes only three months. Once the vegetative state has become permanent, however, recovery is near-impossible – the neural network in the brain is no longer being retained, and cannot be reactivated.
- Minimally responsive, or conscious, state: this is a development from a vegetative state where the patient regains fleeting and intermittent higher brain functions and awareness. Unlike the vegetative state, the patient is conscious – the neural network in the brain has been retained, and is beginning to reactivate. This is one of the harder states of brain damage to diagnose because emergence into consciousness is so erratic – it cannot be reproduced upon command, and signs of the minimally conscious state can easily be mistaken by a doctor for wishful thinking by the patient’s family.
- Locked-in Syndrome: also known as a pseudocoma, this is a situation where a patient is trapped inside their own brain, fully conscious but unable to move anything more than their eyes. It most often occurs when a lesion to the brainstem is caused by a stroke. This can be a very difficult condition to diagnose, as it can resemble a vegetative or minimally responsive state, particularly in its acute stage, where no eye movement is possible. Once diagnosed, however, therapy can occur and quality of life can be improved. A number of cases, known as Incomplete Locked-in Syndrome, can even involve the recovery of speech and the use of one of the upper limbs.
- Akinetic Mutism: this is a condition similar to Locked-in Syndrome caused by damage to the frontal lobe or the midbrain. The patient does not speak or move – however, unlike cases of Locked-in Syndrome, this is not due to paralysis, but to a lack of will. Unlike many other forms of brain damage, the symptoms often begin to appear gradually, although they can appear suddenly following a stroke. This is also a condition which can be treated, and many patients do recover.
- Brain death: this is the point where the brain has literally died, and cannot be healed or repaired. There is no blood flow to or inside it, and all brain functions have completely shut down. This can be a confusing and difficult situation for some families, as their loved one may still be breathing, and autonomic functions can continue for a short time. However, upon turning off life support, these functions will cease. In a case of brain death in an organ donor, the body may be kept alive until the organs can be transplanted, but the person is indeed dead.
Author Robert B. Marks is a writer, editor, and researcher in Kingston, Ontario, who spent several years working as a writer and editor for the Queen’s University Faculty of Law.