That oxygen question (AWARE 2)

A key part of the AWARE study as it moves into it’s second phase, is the monitoring of oxygen levels in patients suffering cardiac arrest and undergoing resuscitation.

Although it is generally accepted that brain functionality is very limited without a good oxygen supply, it may well be the case that some sort of low level functionality, even low level consciousness is possible with a minimal oxygen supply.

It may well be that during the resuscitation process, in some cases, the achieved blood flow to the brain before restarting the heart is just sufficient to support this. A number of factors could account for this possibility if it is found to be so. (Saturation, viscosity, organ mass, size etc)

There is a general rule of blood flow and viability, and also possible blood flow without the heart pumping along a timescale. The rule stands, but there may be exceptions, hitherto unnecessary to understand in the main aim of resuscitation, to simply get the heart restarted. The rule and associated timeline no doubt will have many variables from patient to patient. Closer study of this is I believe a useful endeavour in the field of resuscitation medicine in general, and will provide a good background input to exploring near death experience following cardiac arrest.

I think this is why the AWARE team are going down this avenue.

We think that these patients may have had better blood flow to the brain during cardiac arrest, leading to consciousness and activity of the mind.”
(AWARE phase 2 outline on ukcrn)

In my previous post I questioned why this was being assumed. I say assumed because of the wording. ‘We think’ not ‘We wonder’ or ‘We want to investigate the possibility’.

Semantics maybe, but the answer I now believe lies in the results of the first phase of study. Namely, the one audio only veridical recall, considered validated. I’ll quote my own words in the introduction page. –

Accurate audio perception recorded at a time when the brain has little oxygen and would be flatlined on an EEG, with little to no measurable activity would bring into question the established understanding about the relationship of oxygen, electrical activity, and brain functionality.”

There. That is what the team in my opinion are exploring.

But in that quoted paragraph also is the one aspect that the exploration potentially defies. Dr Parnia often cites in his writings previous studies that show flat EEGs during cardiac arrest resuscitation events. Varying oxygenation cases may become apparent, so will the next step of understanding then be to reanalyse electrical brain activity?

It is worth noting that EEG monitoring is useful as a tool in medicine, but I have heard and read it said, especially in anaesthetist training, that this method of brain activity measurement is not to be 100% relied upon as de facto as to what is going on in a patient’s brain.

So, there is possibly room for re-evaluation there. In my opinion it’s a long shot, but the proposed monitoring will whatever produce a good data piece to move on from.

A more general treatment of the phase 2 study will follow….


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