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Health and medicine
Course: Health and medicine > Unit 3
Lesson 14: Shock- What is shock?
- Shock - hemodynamics
- Shock - oxygen delivery and metabolism
- Shock - diagnosis and treatment
- Cardiogenic shock
- Sepsis: Systemic inflammatory response syndrome (SIRS) to multiple organ dysfunction syndrome (MODS)
- Septic shock - pathophysiology and symptoms
- Septic shock: Diagnosis and treatment
- Hypovolemic shock
- Neurogenic shock
- Obstructive shock
- Anaphylactic shock
- Dissociative shock
- Differentiating shock
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What is shock?
Created by Ian Mannarino.
Want to join the conversation?
- Could young kids get a shock?(6 votes)
- Yes; anyone of any age can go into shock.
And it's not "a" shock, like an electric shock; it's just called shock.(5 votes)
- at approx 6.30 you discuss distributive shock. Im in an advanced degree class and the person teaching on 'shock' provided other classifications of shock as being cardiogenic, hypovolemic, anaphylaxis, neurogenic and septic. She stated distributive shock is old terminology and as a person who is on the international committee for surviving sepsis campaign-she should know what she is lecturing on. So i would suggest updating the terminology to keep up with current trends(1 vote)
- UpToDate, Merck Manuel, Oxford American Handbook of Clinical Medicine (those are just the three sources I've looked at for more information on shock, take your pick as to which one is the gold standard of current medical reference material) all cite "distributive shock" as a present classification of shock. If your lecturer lady wants to unpack distributive shock and just list each type of distributive shock as its own classification (anaphylactic, septic, neurogenic, etc) then she will need to add endocrine shock and drug/toxin-induced shock to her list because she is missing those types of distributive shock...(7 votes)
- How is hypoxia different than shock?(2 votes)
- Hypoxia is lack of oxygen. Shock is a condition brought on by sudden lack of blood flow through the body. The two are related but not the same.(3 votes)
- At, what is a pulmonary embolism? I never understood that. 5:53(2 votes)
- A pulmonary embolism is a blockage of an artery in the lungs, usually caused by a blood clot.(3 votes)
Video transcript
- [Voiceover] I'm sure most
of us have seen those medical shows or those medical movies
where a patient is hauled into the operating room or is in
the emergency department, and the physician is
furiously working on them, while somebody on the
medical team is screaming, "Doctor, the patient is in shock!" Everybody continues to
furiously work on the patient. There's a lot of commotion. It makes sense, because this
is a life-threatening problem. Shock. But what is shock? To understand, let's go ahead
and tackle some of the basics. So we know in the body there is something called the cardiovascular system, which is essentially your
heart and blood vessels. So, here's a blood vessel. Blood passes through blood vessels. The reason we have blood
is to distribute nutrients and energy and oxygen to the
different cells of the body. So here we have some cells. So this is the normal
physiological process by which we deliver oxygen to the tissues. But what if we're not able
to deliver as much oxygen, which I'm doing with these
little white dots here? What if we can't deliver as much oxygen to the tissues as we need? What if the O2, the oxygen that
is delivered, is inadequate? What if it's less than the oxygen that is required by these cells? This is essentially what happens in shock. Shock is inadequate delivery
of oxygen to the tissues. It's also known as tissue perfusion. So what is tissue perfusion? Tissue perfusion is basically the amount, so the volume of blood,
that can be distributed over a certain amount of time, over, or to, a certain amount of tissue. Amount of tissue. So volume over time is
essentially blood flow. So this is flow of blood to
a certain amount of tissue. This could be in grams of tissue. So this might be written as
something like 20 milliliters per minute delivered
to 100 grams of tissue. So profusion is just a
measurement of how much blood can reach a certain amount of
tissue in a given time period. Now we know that cells require oxygen, and know there are things
that can increase or decrease the amount of
oxygen required by cells, So, for example, if you're exercising, you're going to have an
increased need for oxygen. Increased oxygen requirement. But when we talk about shock, we mostly focus on this oxygen delivery. So let's take a look at oxygen delivery through the cardiovascular system. So here we have our heart. I'm going to do a good
old Valentine's Day heart. The heart is really
divided into four chambers. The right side of the heart. This is the patient's right. So you're looking at a patient. This is the right side of their body. And the left side of the heart. We've got the atria,
which is where blood first enters into either the
right or the left side of the heart, and we have the ventricles. So this will be the right
ventricle, and the left ventricle, which will essentially pump
blood to where it needs to go. So let's follow to the
left side of the heart. So we can follow blood flow
from the left side of the heart as it goes and gets pumped to the system, where different organs
of the body, so these are cells from different
organs of the body, receive oxygen, nutrients, glucose, everything they need from the blood. Then blood, after being deoxygenated, returns to the right side of the heart. Then this blood, this deoxygenated
blood, is pumped again from the right side of
the heart, to the lungs. Now obviously this isn't
anatomically correct because the lungs are on the right
and left side of the heart. They surround the heart on both sides. They're kind of situated
on both sides of the heart. But this will really suffice for the purposes of our diagram. And so, blood will be
oxygenated and returned to the left side of the
heart to be pumped again, pumped to the organs of the body. And so this is the cardiovascular system. So when you think about
shock, I want you to think about how the cardiovascular
system is affected so that you can figure out
the different types of shock. Because there are four
different types of shock. First of all, remember
our definition of shock is decreased tissue perfusion. So one thing that we could
imagine is, if we decreased the volume of blood, that
would decrease perfusion. Right? Because perfusion is volume
over a certain amount of time delivered to a
certain amount of tissues. So low blood volume is
known as hypovolemic shock. Hypo means low. Volemic means volume. And so you could imagine
if a patient is vomiting or is having diarrhea,
sorry for the visual. Or maybe they're bleeding. This all leads to volume
loss from the patient. If it's severe, it can
lead to hypovolemic shock. So what's something else that can decrease tissue perfusion? What if we decrease the flow
through the entire system? Well what causes the
cardiovascular system to function? It's the heart. So if the heart can't contract and push blood forward,
that can lead to shock. And so that's known as
cardiogenic shock from the heart. Now what else can prevent blood flow? Well what if there's an obstruction in the cardiovascular system? That's another type of shock. Obstructive shock. There are many examples
of obstructive shock. One example is a pulmonary embolism. A clot in the pulmonary arteries. If this is severe enough, it can prevent blood from flowing
through, which is decreased blood flow, decreased tissue perfusion. So that's another type of shock. Finally, the fourth classification of shock is known as distributive. Distributive shock includes
different shocks such as septic shock, anaphylactic
shock, neurogenic shock. What happens in
distributive shock is fluid ends up collecting in
between the cells of organs that are requiring the
oxygen, and the blood vessels that are delivering that oxygen. If a lot of fluid accumulates, it's harder for oxygen
to get to the tissues. It has to pass through a lot
of fluid to reach the tissues. By tissues I mean the
organs, like kidneys, the liver, or maybe the
gastrointestinal organs. So finishing up, I want
you to ask yourself, what happens to the
gastrointestinal system, the intestines, when they
don't receive enough blood? Well, if it's mild, if they're not receiving enough oxygen and blood. It might be something mild like nausea. If it's severe enough if left
unchecked for a long time, the cells of the intestines, they die. This will lead to bowel perforation, or intestinal perforation.