shockShock is defined as a lack of oxygen to the body’s tissues. Many different things can cause this, and there are lots of different types of shock.

Types of Shock

The first one is hypovolemic shock. This occurs normally during or after a major trauma incident, for example, a car crash, where the patient loses around 20% or more of their blood volume. There is also neurogenic shock, which is a problem within the brain. Cardiogenic shock is where there is a problem with the heart. The most common type of shock is hypovolemic shock.

Shock Scenario

Here is a scenario in which you have been putting a dressing on somebody that has lost quite a lot of blood. Inside their blood vessels, there is less blood flowing around. Therefore there is less oxygen being transferred around the body. Their heart is going to start being much faster because your heart is trying to pump more blood around. However, there is just not enough blood to go around. Although the heart beats very rapid, there is less blood being pumped with every beat than normal. Consequently, you get what a rapid but weak pulse. They are also going to start to look a little bit blue-grey. You will see this especially around the lips and the extremities, because not enough oxygen is reaching there. They will start sweating and feeling very dizzy and nauseous. They may even start vomiting.

If you get to a situation where someone says they are feeling unwell and have undergone bloodloss trauma, you need to lay them down. You want to get them off of a chair and onto the floor. This is because if they collapse on a chair, they could potentially injure themselves even more when they fall off. In the current situation, we need to get more blood into the body and the brain.  By laying somebody down and elevating their legs, spare blood will be flowing from the legs into the body and the brain. This will hopefully make that person feel better and will essentially keep them alive. Elevating their legs 15 to 30 cm is enough.

The important thing then is to keep checking that the patient is not deteriorating. Also, because there is not so much blood going around the body, they may also start to suffer from hypothermia. Therefore, keeping them warm by covering them with a blanket or something similar is essential. Often in the BSI-type first aid kits, there is a foil blanket.

A Medical Emergency!

Hypovolemic shock is a medical emergency, therefore you should call the Emergency Medical Services immediately. Even if after laying them down and elevating their legs makes them feel better, you must call the emergency services. Don’t let them get them up straight away, because all that will happen is that straight away, they will feel unwell again.


One other type of shock which is normally not so severe is fainting. Fainting happens because your brain does not have enough oxygen. Consequently, you will start to feel dizzy. You feel dizzy because your own brain is trying to get you to sit or lay down. If the brain is seriously lacking in oxygen, your brain will make you lay down by making you pass out – you faint. Once a patient faints, they will normally come round very quickly. Like hypovolemic shock, there is not enough oxygen in the brain, so lift the legs up. Essentially, treat for hypovolemic shock. However, if someone has fainted, it may not be necessary to call the emergency services. It may well be that you just stay with them for a while. When they start to feel better, get them up slowly. Don’t get them to stand up straight away, as all the blood will leave their brain and they will just collapse again.

Although fainting, generally speaking, is not a serious medical condition, if someone is fainting regularly, then they should see a doctor just in case of a more serious issue.

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