It took me a while but I finally realized (I think) that there is no way a person could remain conscious for more than a few seconds after being beheaded. The reason is loss of perfusion pressure.
I am not a doctor, but even a 4-day first aid course covers the concept of adequate perfusion pressure, or the need for standing BP to provide oxygen and fuel to cells. Without perfusion pressure there is immediate decline in level of consciousness, as the brain is very sensitive to this. This is why some folks with low blood pressure are prone to fainting when they stand up quickly.
If my head were cut off, the arterial flow would be interrupted, blood would drain back out of my carotids and therefore standing pressure in my bloodstream would instantly plummet. The sensation would likely be much more immediate and profound than just standing up too quickly.
Since perfusion is so basic a concept in human medicine, it is amazing to me that this was not brought up early in the debate.
Any MDs out there who could tell me if this makes sense?
William Blatty had a priest’s head removed and placed in its own lap in his book Legion, leaving the impression that the priest was able to watch his lifeblood pouring out of him, if only for the briefest moment.
I’m sure someone has tested it somewhere, but getting them to admit it might be a tricky proposition.
This has always been my objection to the idea. Sure, double blind studies are hard to come by, but IME (ER nurse) conciousness goes off like a light with catastrophic perfusion loss.
Hell, lots of people get woozy if they stand up too quickly.
We’ve discussed this here a bit before. You are correct, rapid loss of perfusion pressure is one reason why consciousness should immediately cut out. It’s debated that there might be a few seconds of consciousness, but not many.
One item I read once said that the brain consumes about a third of the resources of the human body - food and oxygen. As a result, unless it’s a real advantage, it’s a dangerous waste of resources; this is why most animals are only as smart as they need to be. Too smart, and they are less likely to survive in times of famine.
So I could understand why the brain would need the hig pressure and constant oxygen flow.
How many seconds does it take to pass out with proper pressure to the neck arteries? OTOH, how come someone goofing around, say, sucking helium out of a baloon to talk funny, doesn’t pass out almost immediately? How come they can do 2 breaths or more with it?
Because even sucking pure helium out of your balloon, you still have oxygen in your lungs and blood. It takes a lot of breathing the expel all the oxygen from your lungs and replace it with helium.
Because they maintain blood pressure to perfuse the brain during this time. Blood which is on it’s return trip to the lungs is far from completely oxygen depleted. In fact, if you have a pulse oximeter on your finger and try to hold your breath (and you’re in good health), you’re unlikely to be able to hold it long enough to see the oxygen saturation of your blood begin to decrease. After a couple of huffs of helium, your brain is being perfused with a somewhat less oxygen.
OTOH, a catastrophic loss of cerbral perfusion pressure, such as you would get with a guillotine or a non-perfusing cardiac arrythmia deprives the brain of ALL oxygen and sugar, neither of which it can store (unlike other tissues), and, IME with cardiac arrythmias, the term light switch comes to mind.
If I wanted a decapitated head to remain conscious long enough to view its body (and I can’t say that’s high up on my honey-do list), I’d place the soon-to-be-light-headed person upside down on an inversion table, wean head from body quickly and sharply, then continue to hold it crown down during the presentation. Gravity should maintain adequate cerebral perfusion pressure for the few needed seconds, I would think. Perhaps immediately placing a rubberized gasket atop the open end of the neck and pushing down would maintain adequate pressure even longer—at least long enough for the unfortunate bloke to enjoy a spot of tea and a crumpet before *heading *out (no reason we can’t remain civilized during these types of dis-pleasantries, pip pip cheerio).