Fainting is a common cause of a patient losing consciousness. It is caused by a lack of blood to the brain. This can be caused by anxiety, hunger, pregnancy, stress, worry, tiredness, standing for long periods, too hot or after receiving local anaesthetic containing adrenaline.
If a patient is lying flat, there are much less likely to faint. Often the first sign that a patient may faint is their change in colour. Their skin will appear pale and they become light headed and pass out. Sometimes there is very little warning that someone will pass out.
The patient may say they do not feel well or they they may say they feel sick.
Once the person has fainted, they usually recover quickly. Raise their legs 15-30cm to give more blood to the brain and tell them to rest. Once they feel better and when they are ready, allow them to slowly get up in stages. If they get up too quick, they may faint again.
As the patient recovers quickly, it is not usually necessary to call EMS but you may have to call a family member to escort them home or allow them to rest somewhere.
Regular fainting may be the result of an underling health concern so it is worth seeing a Doctor if this happens regularly or you are concerned.