Sawbones: Near-Death Experiences

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Show: 
Sawbones

This week on Sawbones, Oh No Ross and Carrie! hosts Ross Blocher and Carrie Poppy hosts step in for Sydnee and Justin as part of the Max Fun Great Switcheroo as they look into the history of near-death experiences.

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Music: "Medicines" by The Taxpayers

Comments

Hearing Justin's voice during

Hearing Justin's voice during the sponsor break felt like your dad coming home to check in just when you've gotten used to your new babysitters.

good job

I liked this one. :) Thanks, guys!

Big inaccuracy in this podcast

I'm a physician and a huge fan of Sawbones. I was very charmed by Carrie and Ross, at least at first. Then, there was a problem.

Carrie and Ross describe current brain activity monitors as "one-megapixel cameras" that measure "by proxy" only oxygen supply or blood flow, "not actual neurons firing," so "when we say that people are dead there might still be some activity going on in that brain."

The one-megapixel comparison is fine, but the remainder of that explanation is wholly inaccurate and a little bit dangerous. EEGs, or electroencephalograms, are very cheap, easy, and common tests used to measure electrical activity in brains, usually in the context of measuring seizures or testing for brain death. They may be "one megapixel cameras," but that's a little bit inaccurate inasmuch as they are not terribly specific but pretty sensitive for brain activity. They measure groups of neurons firing, and if neurons are firing, they will see it. They do NOT measure oxygen consumption. They measure electricity.

The problem is that if an EEG, in combination with other tests, shows no brain activity, then in most states this is the legal definition of brain death. Saying that there may be activity that we just can't measure gives false hope to families where brain death is diagnosed for a loved one, because when brain death occurs the heart is still pumping but the brain is dead. This is legal death, and in most states in the US continued care for a brain-dead person is considered both medically futile and unethical. This gets sticky because a lot of families don't want to "pull the plug" on a braindead person because the heart is still pumping (IE therefore they can't be dead!), when in fact death has already occurred and removing life support (or in this instance, death-prolonging) measures is very fraught.

Telling listeners that "there may be activity that we just can't measure" is HUGELY problematic. Brain death is death. Don't muddy the waters and potentially provide false hope to the families of braindead people. Don't make death any harder than it already is for everyone, doctors and families alike. That statement is irresponsible, and ultimately VERY cruel to families where someone has undergone braindeath.

--rcr

Good Points, Thanks

Hi rcr - Thanks for some really helpful points of clarification. We definitely don't want people to come away thinking brain death is not brain death. I don't think we ever used that term, and should have for contrast - Carrie mentioned that when someone is "clinically dead" (stopping of circulatory action) there can still be activity in the brain. That is not controversial.

We were specifically addressing post hoc discussions about people who come back from near death (the subject of the podcast and the operating word being "near"), and champions of NDE proclaiming that the person could not possibly have had any mental activity occurring. Those champions are wrong, because the brain was still alive. No one who has an NDE experience has come back from brain death because... no one comes back from brain death. Hence the mention of Miracle Max and the difference between mostly dead and all dead.

I re-listened to that section, and we certainly could have made that clearer - that's the bummer of the podcast format that we can't go back in and add clarification notes. We certainly hope that listeners do not come away with the impression that a doctor is wrong when declaring brain death, or that our commentary factors into discussions of end-of-life decisions. I really don't think we implied that, though... I feel it's quite a leap from what we said to what you're deriving from it. But this is your field of expertise, so I can see why you'd be more attuned to the things that confuse people.

One would also hope people heed the announcer's admonition that "nothing the hosts say should be taken as medical advice or opinion." Of course, that's not an excuse to get facts wrong.

I definitely goofed when discussing measuring activity by proxy. The proxy part is true - we can't directly pinpoint individual neurons firing in real-time and must detect their effects indirectly - but my follow-up mention of oxygen supply and blood flow is specific to fMRI and NIRS. I was thinking about fMRI as an imaging technique as I was speaking, but that's in relation to mapping neural correlates of consciousness, and not about detecting signs of life. I did not quantify that, so my description left out CT scans, PET scans, MEG and EEG, which are different detection methods with different uses and relative advantages. You're right that EEG is really the most relevant method to our subject, so that was a mistake on my part.

Cheers,
Ross