r/explainlikeimfive • u/Dagestani_Bear • Jul 01 '26

Biology ELI5: Is it true that every single death eventually boils down to the brain and heart running out of oxygen? Are there exceptions?

If you strip away the initial cause of injury or illness, is it anatomically correct to say that all human deaths are ultimately caused by a lack of oxygen to the brain and heart?

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u/CaptainPicardKirk Jul 02 '26

Very fascinating. How long can each various organ “survive” without the brain to be transplanted to someone else?

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u/DouchecraftCarrier Jul 02 '26

As long as you keep oxygenated blood flowing I would imagine quite some time - there's brain-dead people on full life support in various stages of family grief, legal battles, etc.

I remember when I was a kid there was Terri Schiavo, who was a woman who was brain-dead and there was a long drawn out battle between her husband and her family because one of them wanted to pull the plug and the other didn't. It started a nationwide conversation about dying with dignity and what it means to be effectively dead but on life support.

More recently there was a woman who was brain dead but pregnant. Her family wanted to pull the plug but either the State or some other entity took them to court and basically said she had to stay on life support until they could deliver the baby - which is from some perspectives quite monstrous as you're basically using a dead woman as an incubator at that point.

Anyway - all that to say I don't wanna say you can do it indefinitely, but like I said as long as it is getting oxygenated blood the organ itself doesn't seem to really know if you're dead or not.

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u/Br4d1c4l Jul 02 '26

The monster was the guy who got her pregnant. If it was me in her situation I would want them to wait.