NDEs and Anaesthesia Awareness

Question from Uriadka:
“Dr. Jeffrey Long: The key thing is to know a few of the consistently seen elements of near-death experience that are the strongest evidence for their reality. For example, when you’re under general anesthesia, it should be impossible to have a lucidic organized remembrance at that time. In fact, under anesthesia, you’re typically so far under, with general anesthesia they often have to breathe for you. I mean you’re literally, brain shut down to the level of the brain stem and at that point in time some people have a cardiac arrest, their hearts stop, and of course, that’s very well documented. They monitor people very carefully that are having general anesthesia.

So, I have dozens and dozens of near-death experiences that occurred under general anesthesia and at this time, it should be, if you will, doubly impossible to have a conscious remembrance, and yet they do have near-death experiences at this time, and they’re typical near-death experiences. They have the same elements and appear to have them in the same orders as near-death experiences occurring under all other circumstances. In fact, a critical survey question I asked was what their level of consciousness and alertness during the experience was.

Well, even under general anesthetics, under those powerful chemicals to produce sedation, if they had a near-death experience under general anesthesia, their level of consciousness and alertness was identical to near-death experiences occurring under all other circumstances.

There’s absolutely no way the skeptics can explain that away, it’s impossible.”

Let’s go even further: statistically, 1 in 10,000 people have anesthesia awareness. Yet in his study, he had 23 cases out of 2000 patients. They were lucid, had none of the terrible side effects most people have during AA. I think this may prove it.

Answer by SmartLX:
Anaesthesia awareness is a separate phenomenon from NDEs, with one very important difference.

For whatever reason – dosage, faulty equipment, body chemistry – the anaesthetic fails and the patient is not entirely unconscious throughout the whole procedure. This is of course a nightmare come true, as depending on the level of consciousness the patient can experience the sounds, smells and/or excruciating pain of surgery before they’re even able to open their eyes or move a muscle. But the whole reason it’s so scary is that you are unambiguously experiencing real things as they happen, which means it’s easy to determine when it occurred in retrospect even if you give no sign for the duration.

An experience interpreted as an NDE, on the other hand, can occur at any point between the initial loss of consciousness and when consciousness is ultimately regained. If the experience involves elements of the afterlife, there’s no way to place it based on earthly events. If there’s an out-of-body experience where the patient witnesses an event in the room, assuming the events are guessed right the NDE is simply assumed to have occurred at that point, but as you say there’s a period during which there’s not enough brain activity for any such experience. There is always a period before then, and a period after then, where the brain is in an intermediate state that allows dreams and hallucinations.

I made this basic point the last time you brought up this quote by Long, earlier this month. I did not propose that the episodes were happening during periods of anaesthesia awareness, because they really don’t have to. The brain has a pretty wild time dealing with general anaesthetic or any kind of forced unconsciousness at the best of times, and whenever it is active enough to paint an internal scene at the start or end, it will probably do so.

4 thoughts on “NDEs and Anaesthesia Awareness”

  1. I will only read, and if, both the question and answer(s) in future, without commenting, because I find it ridiculous that anyone can suggest that there is soul/spirit without alive brain, and that it can go out of body after brain’s death.

    All relevant science says NO to such idiotic ideas, and so do I.


    End of story.


  2. Look at this piece of typical ‘Augustine shenanigans’. Just ‘slipped’ in shamelessly without any embarrassment (why ?)

    Keith said > “If there’s an out-of-body experience where the patient witnesses an event in the room, assuming the events are “guessed” right”

    So, there you have it. The presumption that NDE’s are always lucky guesses. A priori assumptions from someone who ought to be an open minded sceptic. Pathetic, Keith !

  3. I have no knowledge of the Pam Reynolds case but I am familiar with the phenomenon of burst suppression (BSP). Two claims made about this are wrong:

    (i) It is not characterised by mostly flat brainwaves
    (ii) It does not necessarily preclude processing of sensory information

    BSP is a highly variable EEG pattern found in controlled anaesthesia and also brain pathology characterised by alternate periods of high amplitude electrical activity (burst waves) and depressed (though not necessarily completely flat) waves.

    While EEG measurements have very good temporal resolution, they exhibit poor spatial resolution and it is difficult (and rarely done) to measure BSP simultaneously at all possible brain locations. We cannot assume (as suggested above) that BSPs are always homogenous and occur globally throughout the brain. For example, we know that BSP can be localised with asynchronous (differing) ratios measured between cortical brain regions. Strong burst suppression can also occur in one cortical brain region while being absent in a neighbouring region.

    When we are conscious, auditory sensory information is conveyed to cortex via the thalamus. During BSP coherent activity has been registered in the thalamus and thalmocortical connections to both frontal and parietal cortical regions. The activity is related to the strength of the burst phase. BSP suppression phases need to be especially long before all thalamic neurons go flat. Hippocampal-cortical interactions (important to consolidate short-term to long-term memory) are also preserved during BSP and, paradoxically, some activity appears to increase during anaesthesia. Similarly, the BSP suppression phase does not completely silence brain stem cells.

    BSP states are common in healthy neonates when they are conscious yet drowsy and asleep, so we can be certain that BSP per se does not preclude auditory information reaching the cortex. Experiments have also demonstrated that auditory (and even visual) stimuli presented during deep BSP during anaesthesia invoke coherent cortical electrical activity (i.e., somatosensory evoked potentials that are distinct, such as in response to a familiar voice and an unfamiliar voice). In other words, sensory information appears to reach and be processed (to some degree) by the cortex. Postoperative recall of sensory information during anaesthesia is reliably found in approx 2 per 1000 patients of all ages and is a recognised medical phenomenon.

    TL:DR If the evidence presented in the Pam Reynolds case evidence relies primarily on the claimed impossibility of auditory information being processed during BSP and/or deep anaesthesia then that evidence is either not particularly strong and/or is misleading.

  4. Gary,
    I’m not sure why you’ve decided to enter the debate with that rather odd ‘composition’ above, but I’m afraid it’s mostly incorrect. What I’m stating here is not my opinion; it’s an accepted medical fact. I’m a layperson, I don’t claim expertise. I listen very carefully to what the medical experts themselves know or profess to know.

    Burst suppression flattens brainwaves. That’s simply a fact. The ratio of burst to suppression, varies according to the dosage of barbiturates (then). See here in the paragraph below.

    Therapy (barbiturate, propofol, or halogenated anesthetic) is titrated to an electroencephalographic (cEEG) endpoint. Complete pharmacologic suppression results in a flat-line EEG. Typically, a 1:10 burst to suppression ratio is chosen as an arbitrary endpoint, but this is neither evidence based nor a universal practice. In other words, a 10 second screen of EEG would have 1 second of burst activity and 9 seconds of flat-line EEG. Optimal dosing is unknown and there is no evidence base to guide therapy (6).


    I don’t know if you are familiar with some of the arguments around this case? Dr Gerry Woerlee, who is a very accomplished anaesthesiologist (it has to be said) has ‘weighed in’ on the case many times. He is a hard-line sceptic and believes that Pam had anaesthesia awareness (which explained her observations) even though the surgeons themselves have repeatedly denied this.

    Leaving that aside, I can tell you categorically that Dr Woerlee also accepts burst suppression eliminates any possibility of consciousness. He confirmed that for me via email. Woerlee actually asserts that burst suppression was achieved later in the operation, just before standstill, to be clear.

    However, Dr Spetzler and his colleagues sought burst suppression early because they had found that it offered better “protection” (barbiturate protection) for the brain cells while they are starved of oxygen and glucose, during the time when there was no blood flow into the brain (standstill). Indeed no blood in the brain at all.

    Pam Reynolds clearly heard a conversation (and somehow remembered it) at the same time that she observed the bone saw that was being used to take the roof of her eye socket off. At that time she was under burst suppression, which is, as I said, a pattern of mostly flat brainwaves which eliminates any possibility of consciousness (apparently).

    That’s why the case is so fascinating and that’s why it remains unexplained. Best regards

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