In this micro-lecture, we discuss shock and the five different types of shock Paramedics should be aware of when treating patients. Enrolled students have unlimited access to a rich library of learning materials such as this.
Today we’re going to talk about shock. By definition, shock occurs when there’s an insufficient amount of oxidized blood at the tissue sites. At the level of the tissue. And by definition, that’s what shock is. Here you can see in this video there are at least five descriptions of types of shock, and the typical signs, symptoms, and causes, or mechanisms of reduced oxidisation of the tissues.
But regardless of the nature of the type of shock, they all end up with the same outcome. In other words, the tissues always end up with low levels of oxygen and if it’s not corrected, your patient will become critically unwell and end up dying.
In the context of paramedic practice, when you’re doing your primary survey. One of the first things you will do as a Paramedic/Medic, is to try and identify time critical features of your patient. That’s where identifying and rectifying shock comes into it. Because if shock is something that will kill your patient, and the primary survey is designed to help you identify any abnormal life threats, then putting the two together, you can see how you need to be able to recognise them.
However, it’s not always easy to be able to recognise the causes and the nature of shock. Just take a look at this chart, that shows at least a different five. And I say at least, because it absolutely depends on the type of classification system that you’re using. So, you will see different classification systems.
Let’s start with hypovolemia. Hypovolemia just means a low volume. Now, volume doesn’t just relate to blood. It can be any of the fluids inside your body. So, whenever there’s a low fluid, there’s going to be a state of hypovolemia. These patients will end up with low blood pressure, tachycardia, weak, thready pulse, they are cool, pale, moist skin.
We talk about signs and symptoms, there are always going to be different stages of shock. There’s compensated, there’s a middle ground where it starts to become uncompensated, then there’s the decompensated shock. This one here, this table shows you a mixture of these, rather than going into such specific detail.
But with hypovolemia shock, you can expect to find low blood pressure at the end stages, tachycardia from the outset, because your body’s trying to pump really hard to get the blood around the body, the pulse is weak and thready, because there’s low volume there and eventually it will disappear. The patient will be cool and pale, and they will have moist skin, because they are hypoxic.
However, if you look at cardiogenic shock, there’re some similarities, but also some differences. Cardiogenic shock is to do with the heart. Cardiogenic shock occurs when the heart is pumping, but it’s not pumping effectively enough to pump the blood around the body.
Neurogenic shock is to do with the nervous system. Take for example somebody who has had a road traffic collision and they’ve injured they’re nervous system.
Anaphylactic, as you know is caused by the mast cell. In other words, the mast cell de-granulates and all the histamine, leukotrienes, and the interleukins, they all come out of the cell and cause massive swelling of the airway and the face.
And then finally, septic, which could also be known as distributive shock, but so could anaphylactic, so, again, you can see how there’s differences in the way we describe these types of shock.