You know, there’s been a slew of books discussing what is consciousness.  And, we all have our own definition.  (I think, therefore I am?)

But, seriously, there’s a real issue when someone been hurt- a brain injury (from an accident) or even from a stroke.  How do we know if there’s someone there still?  How long do we wait.

Many of you who never worked in a hospital probably have a fleeting memory of Karen Ann Quinlan. She was in a coma for a decade- five years of which were after a fight between her parents and the hospital about whether she should continue to be ventilated (enforced breathing).   She ‘survived’ for 5 years after the tubes were pulled.

But, this issue is far more common than most lay people realize.  Too many folks who were comatose exist in what is called a vegetative state- the purgatory between coma and consciousness.  These folks may s open and close their eyes- but don’t respond to verbal commands or seem to act in a purposeful fashion.  What do we do?

We don’t have a definitive test to discern which folks will recover from a coma or not.  Do we continue life support?  Or terminate the extraordinary actions?   In the interim, the family and loved ones are perplexed- do they continue life support or terminate those actions?  Does that mean they are killing their loved one?

A slew of researchers at McGill University (Montreal)- Drs. C Duclos, C Maschke, Y Mahdid, D Nadin, A Rokos, and Stefanie Blain-Morase [lead author], along with Drs. M Badawy and J Letourneau (Montreal Neurological Institute and Hospital) and Dr. AM Owen (Western University School of Medicine, London, Ontario) seem to have come up with a test, based upon their knowledge of anesthesiology.  Their article (Brain Responses to Propofol in Advance of Recovery From Coma and Disorders of Consciousness: A Preliminary Study), describing their findings, was published in The American Journal of Respiratory and Critical Care Medicine. 

They knew that healthy folks have a pronounced response to anaesthesia- a specific change in their brainwaves.  That change can be monitored via EEG (electro-encephalogram).  Normally, our brain waves (the alpha ones) peak at the front of the brain, and then have subsequent peaks moving progressively towards the rear of the brain.  (The frequency ranges from 7 to 14 Hz [Hertz, aka cycles per second].)  When these folks are subjected to anaesthesia, they lose consciousness – and the pattern is reversed; it starts at the brain’s posterior, progressing to the anterior.

So, Dr. Blain-Moraes postulated that might be a way to discern what’s going on with folks in the vegetative state.  By providing them an anaesthetic and see if the brain waves flip.

That led to this trial with 12 folks who were in a coma or a vegetative state (or a minimally conscious state), providing each with propofol (an injectable drug- the same given to me before my numerous surgeries this past year to induce anaesthesia).

Four of the subjects responded in an identical fashion to normal, healthy individuals.  Within 3 months of this test, 3 recovered full consciousness.  (Life support was withdrawn for the fourth individual almost immediately after the test, so it’s unknown if that person would have recovered.  Since no one knew what this test would discover, it was understandable that life support could have been withdrawn.)

Eight of the subjects did not manifest the “normal” EEG patterns.  Of these, one died and the others never came out of their comas.

This hypothesis will now be tested using a much larger and wider group of subjects, to see if the preliminary findings hold up.

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