system
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human
ELI5: what is the process of going into shock?
gpt
Paramedic student here. When we speak of “shock” we are talking about inadequate tissue perfusion- basically, for whatever reason, oxygenated blood is not reaching the patients tissues. There are 5 major types of shock- 

hypovolemic (loss of blood volume, ie, the patient is bleeding out)

cardiogenic (there is an issue with the mechanical activity of the heart pumping blood to the body), 

neurogenic (there is an issue with either the brain controlling the heart, or the electrical system in the heart itself)

anaphylactic (life threatening allergic reactions, or other adrenal issues affecting perfusion)

septic (massive systemic infections)

In pre-hospital care (when you call for a paramedic), we can manage some of these. For hypovolemic, we can give you IV fluids to replace lost blood volume, but we have to balance that with making sure theres still enough actual blood there to carry oxygen to the tissues. For septic, we give fluids as well, but in the hopes of diluting the blood- theres very little we can do in the field to actually combat septic shock. For anaphylactic shock, we can give medications to mitigate and lessen to bodies reaction to what ever triggered the event. For neurogenic shock, we try to control heart rate and BP, without letting the system crash. For cardiogenic, we try to get you to the hospital as fast as we can, cause there’s not much we can do for you in the field. 

Another issue with shock is that there’s 3 levels of shock- compensated, decompensated, and irreversible. Compensated shock is the early stage, where the patient is sweaty, pale, and has a rapid heart rate. This is the stage that is easiest to manage. Signs/symptoms can include agitation or anxiety, fast heart rate (tachycardia), fast breathing (tachypnea), nausea and/or vomiting, and a weak or thready pulse. Decompensated shock is the mid stage, where the patient becomes mentally altered (seems intoxicated, or passes out entirely), has no pulses in the extremities (but still has a carotid pulse), labored or odd breathing, and a falling blood pressure. This is the shock stage that we throw everything we have at, in order to keep the patient alive so we can get them to a doc. The last stage, irreversible shock, is just that, irreversible. If you hit that point, you’re gonna die. Medics and doctors will do everything they can, but at that point, it’s a losing battle. Patients in this stage have lost the carotid pulse, they’ll have very shallow and irregular breathing, very low blood pressure (hypotension), and they’ll be unconscious. 

Our ultimate goal, regardless of the type or level of shock, is to get you to a hospital, or ‘definitive care’ as we call it. Medics, despite all the tools, techniques, and meds at our disposal, are bandaids. We can stabilize, but it takes a doctor to fix the problem. So if you call 911, and the medic says you need to see a doc, go see one. Ideally, the medic will take you, but not every fire service does their own patient transports.