Well...
Let's keep this basic. Shock is a drop in blood pressure. Typically, someone gets into shock when their systolic pressure drops below 80 mm Hg. But a friend of mine (paramedic) has seen a woman whose systolic BP was UNDETECTABLE and who was still running around and screaming, so it's not, apparently, an absolute rule
As a rule of thumb, blood pressure is determined by three things : cardiac output, blood volume and the blood vessel's resistance.
There are four causes for such a drop in blood pressure... but actually it's three :
1) Lack of blood VOLUME : this is called the hypovolemic shock. It's typically what happens when you bleed too much, or when you're severely dehydrated, when you're badly burnt and loose physiologic fluids, etc.
2) The pump fails to push hard enough : this is the cardiogenic shock, which often happens when the heart, for some reason, does not have enough power to maintain the blood pressure high enough.
3) The allergic shock (anaphylactic shock) happens because our blood vessels are dilated by the chemicals produced massively by our immune system. As the blood vessels expand, there is more room for blood in the system and pressure drops.
4) The sceptic shock (cause by generalized infection), follows more or less the same rules as the allergic shock : the blood vessels expand.
What happends when such a thing happens is that the person more or less loses consciousness. In order to get the blood pressure back up, the whole system starts to fight hard : heart rate increases, peripheral blood vessels shrink down, etc. All the blood is concentrated around the center of mass : brain, heart, lungs.
So the skin is pale, the pulse is fast, yet kinda weak under the finger. The person will often experience nausea/vomiting, huge thrist and extreme coldness everywhere. This is typically why we keep'em warm. It will reassure them and it also will help the shock to dissipate afterwards.
What to do ?
Elevating the legs is good in theory, but practically it has little benefits as the blood vessels in the legs already contracted and pushed out the blood. It's also a risk as you never know if a victim has some hidden trauma.
Protect the victim from any danger source, stop bleeding if it's there, and seek medical assistance. If you're neck deep in a survival situation and there's no medical help but you, here's the guidelines :
The victim should ideally lay down. Most of them will be found that way anyways. Always check for airways. If vomiting, bleeding near/in the airways, etc, the victim must be put in lateral safety position (or whatever it's called over there) : mouth lower than the aiways so fluids will pour out by themselves. The rest is details.
Even if you suspect a spinal trauma, you must make sure the airways are free. This means you check the victim closely and as soon as there is an airways problem you move... and if you must leave the area, turn the victim on his/her side and make sure the fluids will pour out (there is a simple and effective technique to do that safely, and with minimal stress on an injured spine, you should seek a course and learn it !!!).
The victim should not be given to drink (risk of vomiting, not mentioning complications with an eventual anesthesia).
Depending on the cause of the shock, treatment will either be to
1) give back blood volume (IV), or in some cases it can be done rectally but I won't get into this here :
2) stimulate the heart function (with drugs, if you're not a doc you don't need this info, if you're a doc, you don't need this info).
3) shrink the blood vessels back to normal AND stimulate heart function, with drugs as well (same remarks, except for allergic people : carry your adrenalin/epinephrin/epipen/etc.).
Reassuring the person WILL help a lot. A positive mindset and the urge to fight and survive are often procuring the person with their own self-produced set of drugs and that does help a lot. Just never let them quit.
Cheers,
David
