What is the physiological difference between sleep, unconsciousness and anaesthesia?
In: Biology
Neurophysiologist in the Operating Room 15 years experience: lord butterfingers is correct. Read his reply: and (my career) is responsible for measuring, documenting, and interpreting the effects of anesthesia on nerve activity vs. surgical effects of nerve activity. Brain / spine / nerves / muscles : all of it.
ELI5: sleep- your brain is in control of your sleep: brain monitors your body while in sleep: any external stimulation or change or noise or cold or hot or anything: the brain and body wake up and respond. Your brain allows body to move while you sleep. (Breathing, roll over in bed, flop you legs around when they get uncomfortable, pull the covers up if you cold, kick covers off if you get hot)
General Anesthesia: anesthesia professionals monitor your sleep: professional sedate your mind, reduce your threshold for pain, and most of the time they relax your muscles. Any external stimulation does not get registered by your brain and your muscles are relaxed so there is no response: your body can not breathe on its own: it can not roll over , can not pull up the covers, can not kick the covers off, and if you your blood circulation in your legs get reduced (like the feeling when your foot falls asleep ): under general anesthesia your body will not be able to respond and adjust itself under general anesthesia: that is why you have professionals monitoring and taking care of your anesthesia AND the neutral position of your body so your legs are not falling asleep because your ankles are crossed for several hours: and yes: we check all of that in surgery while you are asleep! KEY Point: it is controlled, monitored, and quickly reversible at end of your procedure. I.E. you wake up and return to normal function within a few min. Of time.
Also: different anesthesia drugs have different effects n EEG: and any combo of drugs as well.
Unconscious: ELI5 – the the mind is protecting itself and your bodies vital organs only: something caused the brain to go into critical status: so instead of the brain monitoring every single body function while you sleep normally: now it is only monitoring g the basic functions: this is not controlled by an anesthesia professional: and there are different levels of what the brain is controlling / functioning and what is not: but the key point is the brain chooses to stop control over various body functions on its own (for whatever reason) and when the brain is ready to resume responsibility- it will resume control on its own: (depending on level of trauma / damage / reason in the first place). Think about a choke hold from two kids playing rough and play wrestling- and one kid just holds the choke hold a bit too long and his friend passes out: unconscious kid collapses and looses muscle control and tone: then kid starts to breathe as soon as the hold is released : then the kid Opens his eyes within 5 seconds: feels a little dizzy for 15 seconds: then is back to normal. This kid’s Brian only shut down a few functions and only for a few seconds: this kid did not loose lung control, bladder control, blood flow to his extremities, blood glucose control, or any other major system control. now think about the traumatic car wreck where patient is ejected from a vehicle and suffered massive blood loss and head trauma: this patients brain will shut down several functions for a very long time while the body ( and brain) recover.
Now think of the patient that is actively having a seizure and looses consciousness. This is electrical brain activity spikes that confuse the brain: and it gets overloaded an has to shut itself down: and even a 30 second seizure can cause bladder to empty, can cause vomiting, can cause the patient to bite his tongue off. OR some seizures cause no muscle issues what so ever: some seizures can happen to a girl sitting in her desk at school: seizures can last 30 seconds: and this girl will look to her classmates and teachers completely normal: but the reality is her brain is resetting , her eye lids may be closed for 30 seconds, or she may appear to blinking rapidly for 30 seconds: but she does not even slouch her head or shoulders: she does not fall over, she does not loose bladder control and she does not vomit: she does not bite her tongue: she just sits still and silent for 30 seconds.
All the examples I have given look different on EEG. Time, electrical frequency, even different medications “knock out” the eeg patterns in different ways.
Hope this helps
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