Eli5 how being in a coma works


What puts your body into a coma, why can’t you wake up on command, what determines when you wake up, what is it like being in a coma, are you aware of your surroundings, how is it that your body is still regulating like normal, etc. This is all so mind-boggling.

In: Biology


And would you need food?? Like you dont just wake up and eat a burger and go to sleep again? Or do you?

I’m here for this. If you were in a coma 500 years ago, would you just die? Can you make a comatose person eat and drink? Is “being in a coma” a relatively new thing, would you just be buried alive 500 years ago?

Intensive care doc here. Comas are my jam lol.

Coma is not a specific thing, as one commenter stated it’s a prolonged period of unconsciousness. The ones we hear about in fiction, the “I got hit by a truck and was out for weeks months years then woke up”… I’ve never ever seen that. It’s not utterly unheard of but sooo rare.

Big caveat: I’m writing this as an eli5. This is a topic we could talk about for months and never get to the bottom of. I’m going to generalize and simplify and use analogies that break down at certain levels, but it’s a decent basic “what is this”.

Generally two big categories as I see think of them:

Medically induced. Usually when you need to be on a ventilator, or pain just cannot be controlled to the point that the person is in sever distress, that type of stuff. We use sedation to keep them out. Then regularly withdraw sedation when we think they might be able to handle breathing again, turn the assist off on the vent, and if they can pull their own breaths and meet a few other criteria boom. Tube out.

Trauma induced. This doesn’t have to be mechanical trauma, it can be hypoxia say from a hanging suicide attempt, chemical trauma, etc. The brain is damaged and inflamed and not working right. So we support them, and do some scans to see if we can determine obvious permanent damage. If it’s a gray area we in consultation with the family wait and see until the situation declares itself. The vast majority of the time there is sever brain damage and the patient does not have a good outcome, it’s really a matter of how much damage is done and if there is enough left to support a quality of life that person would find acceptable.

Being in a coma is incredibly damaging on its own even if you recover from the initial insult. The drugs we use for sedation produce HIGE problems – most folks have severe ptsd from hallucinations and dreams coming in abs out as we are doing horrible things with needles and tubes and restraints. The muscle wasting is incredible – if you are on a vent for 2 weeks, you have a 1 in 8 chance of being strong enough to do your own dishes after a whole year of rehab. It’s awful. The diaphragm starts atrophying as soon as the vent comes on, and so their breathing is very weak.

We provide nutrition either through the iv (usually last choice) or through a stomach tube. Waste is elongated through tubes in the urethra and rectum. We do the best we can with constant position changes to avoid bed sores, but the human body isn’t meant to be laying down for long periods and after a time the best efforts fail. You have a lot of I’ve and lines going in, so infections are a constant battle. You are in an icu where the sickest ppl on earth are, so you are exposed to all the worst bugs – and even the best infection control procedures pale when matched against bacteria. They are very very good at what they do.

its cost so much hospita
l expenses depending upon how many year u r in coma
stay safe from falling anywhere
dont take risky beahaviour