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Current time:0:00Total duration:7:16

Video transcript

I'm sure most of us have seen those medical shows or those medical movies where 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 and everybody continues to furiously work on the patient there's a lot of commotion and 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 and blood passes through blood vessels and the reason we have blood is to distribute nutrients and energy and oxygen to the different cells of the body and 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 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 and this could be in grams of tissue so this might be written as something like 20 milliliters per minute delivered to a hundred grams of tissue so perfusion 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 though 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 and I'm going to do a good old Valentine's Day heart and the heart is really divided into four chambers the right side of the heart and 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 would be the right ventricle and the left ventricle which will essentially pump blood to where it needs to go so let's follow 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 or 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 and then blood after being deoxygenated returns to the right side of the heart and in this blood this deoxygenated blood is pumped again from the right side of the heart to the lungs now this isn't obviously this is an anatomically correct because the lungs are on the right and the left side of the heart they kind of surround the heart on both sides they kind of are 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 out 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 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 decrease the volume of blood that would decrease perfusion right because perfusion is volume over a certain amount of time deliver to a certain amount of tissues so low blood volume is known as hypovolemic shock hypo means level emic means volume and so you can 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 and 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 what if there's an obstruction in the cardiovascular system that's another type of shock obstructive shock and there are many examples of obstructive shock but 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 and finally the fourth classification of shock is known as distributive and distributive shock includes different shocks such as septic shock and a flat kick shock neurogenic shock and 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 and 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 tissue and 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 but if it's severe enough if left unchecked for a long time the cells of the intestines may die and this will lead to bowel perforation or intestinal perforation