/sci/ - Science & Math

I particularly want to know:
>how blood loss affects a person's capacity for movement
>whether individuals vary in their tolerance to blood loss

>>15419024
if you've ever seen how halal meat is slaughtered then you don't need an explanation. the animal basically passes out and its heart stops after a jolt of adrenaline to increase heart rate

>>15419036
>if you've ever seen how halal meat is slaughtered then you don't need an explanation.
Then I guess physics was pointless since we've all seen a magnet pick up things.

>>15419029
Just let your hostage go.

>>15419062
The Bible advises to kill all the firstborn children in such situations.

>>>/lgbt/

>>15419024
she cute

>>15419024
Vasoconstriction helps for a bit. You go into shock. You lose perfusion, so your cells don't get oxygen anymore.
They switch to anaerobic metabolism, which accumulates lactic acid. Acidity rises to dangerous levels.
Your heart stops being able to pump blood due to lack of oxygen. Your heart stops.
You get brain damage from lack of oxygen, and the rest of your cells also die from the rising acidity/lack of oxygen.

>>15419536
In the case of bleeding is vasoconstriction localised to the area of trauma? Is it more general?

>>15419600
Blood pressure drops everywhere, because there's just less blood.
Your arteries are supposed to be under enough pressure that the stuff in the blood perfuses inside the cells. It has to be so explosively pressurized that the oxygen is forced through the membranes.

If you lose blood, you lose pressure everywhere. So you need vasoconstriction everywhere to make up for it.
Your heart also beats faster to help increase the pressure.

>>15419024
Like this
https://goredb.com/w/4WZmCDj388z75NKhCtneEZ

>>15419607
Go make some OC instead of reposts.

>>15419608
Yes, but I'll need to score some PCP first.

>>15419603
Amazing thanks.

Does adrenaline preemptively vasoconstrict in the absence of blood pressure drop?

If vasoconstriction happens everywhere that's pretty bad for the important organs right? Isn't the body able to triage and prioritise blood to the brain over limbs?

Can a bio person answer this question for me:

Does donating blood reduce blood pressure?

My brother was a regular blood donor but was recently denied because he has high blood pressure and I just thought it would benefit him if he could get rid of some blood.

>>15419629
>Does adrenaline preemptively vasoconstrict in the absence of blood pressure drop?
Adrenaline is a general adrenergic LET'S FUCKING GO chemical signal. It makes your heart beat faster, your lungs dilate, it does vasoconstriction, it prepares some rapidly available energy for your muscles, and a bunch more
It's what you feel when something jumpscares you. That short feeling of ready for action.

>If vasoconstriction happens everywhere that's pretty bad for the important organs right? Isn't the body able to triage and prioritise blood to the brain over limbs?
Yeah it does do that, I'm just simplifying a bit, but the point is that it's not just at the site of the injury

>>15419632
It reduces blood pressure temporarily yeah. But you drink a bunch of fluids after to start rebuilding the blood you've lost immediately. It's a temporary drop, not a solution for chronic hypertension.
You don't donate blood for the purpose of reducing blood pressure. They don't let you donate too often for a good reason. You'll just get anemia if you keep losing blood chronically.

Hypertension should generally be safe to donate blood if it's controlled properly. But they probably denied her out of caution. The less stable and normal your situation is, the more risk you take destabilizing the system by causing some stress of blood loss

>>15419653
What is the cause of hypertension?
I personally haven't been to a doctor in many years due to social anxiety, so my knowledge of common health symptoms is very limited.

>>15419661
Plenty of possible causes. Just old age. Diabetes. Obesity. Various diseases.
Honestly, try asking ChatGPT if you have social anxiety. You have to be careful because it's sometimes confidently wrong or just makes stuff up, but humans do that too so it's not very different from taking random advice on 4chan.
It's pretty good for basic stuff in a field you don't know

>>15419667
Mostly asking for my brother, but he is a bit overweight so that is probably why.

Funnily he is the complete opposite to me when it comes to seeking medical advice, he will book a physiotherapist if he has a stiff neck from sleeping badly lol.

Wish I didn't feel so ashamed to seek medical attention.

>>15419678
Honestly doctors have seen everything, completely desensitized to the wildest shit.
You should probably see a shrink for the social anxiety tbqh. They'll just be happy to see someone who can actually be helped, since most of what they get is horribly depressing cases

>>15419685
Been there, I'm on my SSRI's for decades.

The paradox of social phobia is that the act of talking to a therapist triggers the extreme fear that you are trying to get rid of.

Maybe next year :)

>>15419690
SSRIs are absolutely shit for social anxiety. Literally anything else can decrease inhibition.

>>15419694
>SSRIs are absolutely shit for social anxiety.
True, I'm on it for depression.
I hate it though, but once you've been to the point of seriously attempting suicide and then have a family member discover you in that mess, I'm too afraid of myself to not take it.

>>15419690
Fair enough. SSRIs are better than nothing, but not the panacea for anxiety (evidently not enough for you).

The most effective drug for anxiety is (unfortunately) benzos. Sadly it's horribly addicting in an insidious way and a little too effective... So doctors hate to prescribe it. It works but it's basically guaranteed long term dependence.
Good old EtOH is a workable shittier substitute as a last resort, but alcoholism isn't all that much better than benzo addiction, end you end up obviously drunk which is suboptimal

Anxiety is kind of ass

>>15419636
If someone's on the ground having lost a lot of blood, how come they can't just stand up? Is it because the muscles don't have enough oxygen due to a drop in blood pressure?

>>15419715
Blood loss makes you feel weak, and you don't really want to stand up, because that might cause you to be injured further/lose more blood
You feel very weak because it's a survival mechanism. If you have blood loss you need to put pressure with your hand or with a bandage to stop the bleeding, and then stay still to give it a chance to start coagulating at least a little bit.

At some point if you lose enough blood, you just pass out, or you're so weak that you can't stand up even if you try, and then you eventually pass out

>>15419717
>You feel very weak because it's a survival mechanism.
Is this the main factor that causes people to react differently to blood loss?

>>15419725
I mean, the gist of it is that you need to conserve your energy and your oxygen just to stay alive. If you start getting up, that's burning a lot of sugar and oxygen at the worst possible time.
That's the physical situation. Then how people react to that is psychology, and I can't really explain that

>>15419730
How come the body can't just out-repair every bleed?

>>15419763
Because God is a hack engineer.

>>15419763
Otherwise you couldn't kill other animals since they'd be essentially immortal, and we'd all die of hunger

>>15419768
>>15419770
Nah seriously though why does clotting fail in some cases?

>>15419898
Blood needs to be still for clotting. That's how the body prevents clotting from happening inside your veins and causing deadly thrombosis.
If it's pissing blood everywhere, clotting can't function. Once you close the wound, stop the blood flow, and put a bandage, the whole clotting cascade can do its job.
After that wound healing is a whole complicated process. But you need to stop the bleed before clotting can work, that's all.

>>15419697
It also depends on what you have. Low doses of amphetamines have proven efficacy for OCD.

>>15419607
>https://goredb.com/w/4WZmCDj388z75NKhCtneEZ
come on dude, i was eating

Bump.

>>15419024
All your organs shut down and you die. Once you lose too much blood the damage is irreversible. No amount of transfusion can save you. Your body will continue to irrevesibly shut down over the next several weeks.

>>15419069
No it doesn't.

>>15421155
>Your body will continue to irrevesibly shut down over the next several weeks.
Is there a term for this kind of condition?

Bump.