Brief loss of consciousness (less than 30 minutes) is called a faint.
Why does a person faint?
It is caused by decrease in the blood flow to the brain that can occur with pain, starvation or even on hearing shocking news. Commonly it occurs on prolonged standing especially in a crowded place. Due to failure of the nervous system a significant amount of blood pools in the legs, thus reducing the flow to the brain.
What happens when a person faints?
A person when he faints loses control over the body posture and collapses and even falls down that may lead to injuring himself/herself while falling. Sometimes when a person faints, he/she may complain of blackness in front of the eye or dizziness prior to fainting. When you examine a person who has fainted, you’ll find that the person is unconscious. His/Her pulse may be slow and the skin may be pale.
What should you do when a person faints?
If you find a person has fainted, always
check the ABC (airway, breathing, pulse) of the person. If the person is not breathing, start CPR in the person. Once the ABC has been stabilized, raise the person's legs to increase the blood flow to the brain. Loosen the clothing. Splash some water on the face to help the person gain consciousness. Once the person regains consciousness encourage the person to lie down until fully recovered. Then gradually help him/her to sit and then to stand up.
If the person is still unconscious after a couple of minutes, call for an ambulance.