“He heard the news & went into shock.” Well, no he didn’t. Terrible news can incapacitate you emotionally, even make you faint. But you’ll wake up. If you’re, medically-speaking, in shock, then without treatment, you die.
Shock means inability of blood to circulate. Blood carries the oxygen and nutrients that every cell of our body needs to function. When circulation fails, everything breaks down. And that’s that.
There are several main reasons for Shock:
- Blood Loss
- Cardiac
- Anaphylactic
- Septic / Toxic / Other
Blood Lossย —ย Bleeding out, from internal bleeding, bullet wound, etc.ย Treatment involves IV’s to keep circulation flowing, blood transfusions, & usually surgery to fix the cause.ย The same type of shock can happen from extreme dehydration (massive vomiting, diarrhea, etc) [called “hypovolemia,” meaning “low blood volume”], in which case the patient needs IV fluids & treatment of the cause.
Cardiac Shockย —ย This is due to a heart problem of one sort or another, in which the heart can’t pump blood well enough.ย Cardiac arrest means the heart stops completely, then death occurs in 6 minutes.ย With cardiac shock, it takes longer.ย This can occur if a heart attack kills enough heart muscle, if the heart’s electrical system makes it pump too slowly or erratically, or a number of other conditions.
Treatment is not to give IV fluids, because that’ll make it even harder for the heart to pump. Maybe we can fix the original problem, sometimes we give medicines to help the heart pump better, sometimes specialists can even insert a device to temporarily help the heart. All this gets done in an ICU. And a lot of times, it doesn’t work.
Anaphylactic Shockย —ย “Anaphylaxis” means “allergy,” the severest kind.ย It can be caused by medications, bee stings, peanuts, etc. etc.ย The allergen (substance) sets the immune system in motion inappropriately.ย Lots of chemicals get released into the blood stream, which cause the arteries to lose their strength.
Imagine squirting water through a hose by holding your finger over the nozzle. If you let go, pressure drops, and the squirt turns into a lazy trickle. This is what happens with anaphylaxis, since our arteries need to be tight enough to keep blood flowing. It’s call “vasodilatation” (dilating, or opening wide, or blood vessels).
Treatment is immediate epinephrine, a natural hormone (its synonym is “adrenalin”). This can be given by an “Epi-Pen” in emergencies. Epinephrine serves to counteract the allergy, keep arteries constricted (opposite of dilated), help the heart pump, and keep bronchi open in the lungs. Emergency medical personnel can also put in IVs for the shock, but epinephrine is essential. Antihistamines (Benadrylยฎ, etc.) are useless (they only help itching), steroids take hours to work. Epinephrine is essential, there is no substitute.
Anyone who needs epinephrine should call 911 and go to an ER. Repeated doses may be necessary, since the anaphylaxis can last several hours. It can also come back hours later (up to a day or more), so patients need extra EpiPens to keep on hand just in case.
We diagnose anaphylaxis & give epinephrine in the following cases:
1. Sudden illness with either itching all over or swollen face, eyelids, or lips, PLUS either
- Sudden shortness of breath; or
- Shock (low blood pressure)
2. Exposure to a substance either famous for causing allergies, or known to cause them in a specific patient, PLUS:
- Swollen face, lips, and/or eyelids
- Shortness of breath
- Shock (low blood pressure)
- Vomiting or abdominal cramps
A professor many years ago told me a story a student had told him — she was in an elevator, a bee stung her, and she began to get an anaphylactic reaction.ย A man inside realized her distress, didn’t know what to do, put his hand on her shoulder.ย The student got so angry being touched by a strange man, her body set off a natural “fight or flight” response, and her own adrenalin (epinephrine) calmed her reaction.ย Moral — in such a case, maybe do something immediately outrageous or obscene (but explain rapidly to bystanders why).ย I’ve never had occasion.
Septic / Toxic / Other Shock
These are all called “vasodilatory shock” because the loss of blood pressure is caused by arteries dilating (see above under Anaphylactic Shock, which also causes vaso-dilatation, but has very specific treatment).ย Septic shock is the most common of these, caused by toxins produced by various germs.ย Toxins can also be produced by other diseases, and some plain old poisons can cause shock.ย Severe low blood pressure can result from a few diseases, as well as from spinal cord injury.
All these types of shock are treated with IV fluids, to keep blood moving. But the main treatment for each depends of course on the specific cause (antibiotics for infections, etc.)