Talk:Brain death
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Right now, this article has a tautology: "permanent" cessation of EEG activity is not reversible: well, that's true by definition.
Question: can brain electrical activity ever cease reversibly? What about deep anaesthesia, or hypothermia? The Anome
- See the ECT article for one possible answer: does anyone have a cite for this?
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- Propofol brings about a dose-dependent diminution of cerebral blood flow, decreases global cerebral metabolic rate, and is potent enough to create a flat electroencephalogram in high doses. This state is rapidly reversible with no neurologic change thereafter.
- "Brain death" cannot be diagnosed (by EEG) in the presence of such EEG-dampening drugs. - Nunh-huh 19:19, 31 Mar 2004 (UTC)
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[edit] irreversibility of brain death
I revised the page fairly extensively, no offense intended. I am a practicing transplant surgeon and know quite a lot about the topic. The key point I would like to make is that brain dead individuals not only have lack of brain function, they have actual necrosis (death) of all brain tissue. Thus, profoundly hypothermic people can have flat EEGs but are not brain dead, at least as clinicians use the term. Assessing cerebral blood flow with radionuclide scanning (or, historically, arteriography) is extremely useful and eliminates any uncertainty about whether recovery is possible.
Another important point is that anyone with a neurologic injury severe enough to have any question of being brain dead has a negligible chance of meaningful recovery, even if they still have some respirations or other brain stem function.
- Necrosis, now that's irreversible. Should we emphasize that as the "true" definition of brain death, with the various types of tests as a way of detecting the absence of necrosis? (ie "brain life") -- The Anome 06:10, 1 Apr 2004 (UTC)
While it is true that flat EEG's can occur in situations where the individual is not "brain dead", it is not correct to say that brain dead individuals have necrosis of all brain tissue. For one thing, brain death can often be determined within 24 hours of whatever event caused the brain death, and that is too soon for necrosis of the entire brain to have ocurred. The important thing to remember is that brain death criteria are present to determine both the complete and irreversible loss of entire brain function. Things like hypothermia and drug intoxication may cause loss of entire brain function for example, but the loss of brain function in these instances is potentially reversible so is not equivalent to brain death. Necrosis has never been a criterion for determining brain death.
[edit] Thank you
I thought this was an excellent encyclopedia article. It's understandable to the layperson, yet specific and scientific. Thank you. jengod 20:36, Feb 14, 2005 (UTC)
[edit] Confusing Term
Another ambiguity is the use of the term "brain dead individual." If someone is brain dead they are legally dead. Once a person dies they are then a corpse and no longer an individual. This is not a trivial matter as the entire concept of brain death does not at all address the issue of what it means to be alive or dead, but is just a list of criterion to determine irreversible loss of entire brain function. It is clear to me that society has not accepted the concept of brain death as equivalent to dead because of the use of phrases such as this one.
This article needs a complete rewrite.
- One can have an individual chair, or an individual shirt. The term seems fine for reffering to living or dead or non-animate things. HighInBC 06:36, 2 March 2006 (UTC)
[edit] The brain makes the individual
The answer is simple:
The legs are for locomotion
The arms are for manipulation
The torso is for life support
But... it's the brain that makes up the individual, and the face that's its identity to others.
[edit] Can somebody explain this to me?
My little cousin was involved in a serious motorbike crash and was rushed to the hospital straight after the acccident. They saved his life although he has lost his eyesight and sense of smell. He was concious and abled to communicate with us by kicking his legs. We were told that his chance of surviving was good as he was only young. He was 18 at the time. Sadly, 11 days after the accident, he was pronouned brain dead. The doctors kept him breathing and his heart beat for another day so family members from abroad could come and see him for the last time. We all watched his heart beat dropped to zero by his bedside.
I am so confused and curious... my understanding was that his brain was functioning when he was at hospital, what has changed? What has made his brain decided to stop working?
-A reply- Without knowing the exact circumstances of the case it is difficult to be specific, however, brain death (or brain stem death) can be caused by a whole variety of things, including trauma, bleeding into the brain or brainstem, infection or lack of oxygen/blood supply to the brain or brainstem. I appreciate that he was conscious and communicative for some days before his death, but some of the above factors can cause brain death even weeks after the original accident. If you really want to find out more I suggest you speak to the doctor(s) caring for your cousin, they are usually very approachable and understanding. I am sorry for your loss.Mmoneypenny 21:09, 21 September 2006 (UTC)
[edit] Other thoughts
In earlier times cessation of respiration and heartbeat used to tell dead or not and a common man could determine that too. Now with science all of this support the various definitions of death make it almost impossible to conclude whether the LIFE is there or not.
- It's because there is no such thing as "life". There is only a collection of parts that fail. Defining death is a matter of picking which failed parts, typically the heart or the brain, justify giving up and letting everything else fail. 76.169.201.183 21:53, 14 January 2007 (UTC)
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- A.K.A. you can keep cells alive while certain parts of the body are dead, it's the sum of the whole that makes "conscious life" possible. However without the brain this isn't possible while the body can still be kept alive by machines performing the tasks the brain normally does, the individual is no longer the person they were when they were consciously alive. They're technically alive, although their brain is dead, this is the subject of debate on whether or not people should be kept alive or not because the recovery of brain cells and such is very poorly understood as it is a very long and complex process. The irreversibility factor is difficult to assess but severely extensive damage is usually justification enough. Just some thoughts... 70.162.43.130 06:58, 20 March 2007 (UTC)
[edit] Springclean
Wow, yeah we need a springclean here. Now if only I can find some time... I'll come back end of December and see if I can't lend a hand.Mmoneypenny 21:36, 21 September 2006 (UTC)
[edit] Just some thoughts post a long day in ICU!
This paragraph could be confusing to the lay-person: "Note that brain electrical activity can stop completely, or apparently completely (a "flat EEG") for some time in deep anaesthesia or during cardiac arrest before being restored. Brain death refers only to the permanent cessation of electrical activity. Numerous people who have experienced such "flat line" experiences have reported near-death experiences, the nature of which is controversial."
The typical use of "flat-line" refers to the ECG or the lectrical activity of the heart not the brain (EEG). In the vast majority of anaesthetic cases one monitors the heart and not the brain.
Also, in the ICU I work in the diagnosis frequently goes to a 4 vessel cerebral angiogram to make fully sure that there is an absense of flow. This is the "gold standard" of brain death. Frequently a person which such massive injuries as to cause brain death will have multiple cranial nerve palsies which makes cranial nerve testing unreliable.
One final thought - I think it should be made more obvious that pronouncing a patient "brain dead" is only required to allow for legal organ donation. If donation is not an option then life-support can be withdrawn without confirming brain death if the hope of any meaningful recovery is lost.
Sorry I have no idea how to edit this myself! 220.245.182.82 11:45, 7 October 2006 (UTC)Jamie
