Fainting
What is it?
Fainting is a sudden and temporary loss of consciousness, where the person falls to the floor. It is accompanied by muscle weakness.
Causes
A faint occurs when oxygen cannot reach the brain effectively. There may be many reasons for this.
Intense stress, fear, pain or anything that suddenly increases pressure inside the body can cause a vasovagal attack. Here overstimulation of a major nerve (the vagus) slows the heart rate and lowers blood pressure.
Fainting may also result from hypotension, or low blood pressure. This can occur when someone stands up suddenly or is dehydrated. More rarely, fainting is due to abnormalities of the heartbeat.
Anyone may be affected by fainting, but people who are unwell or dehydrated are at greater risk. It is also common in pregnancy.
Symptoms
The person may start to feel dizzy and light-headed.They may feel nauseous sweaty and weak. They then collapse to the ground and are unconscious for a few moments before coming round. They may feel woozy or nauseous for a little while afterwards and may vomit.
Diagnosis and treatment
After fainting, a person should return to normal fairly quickly. If they don't, or have problems such as weakness or inability to speak, it may be more than a simple faint.
If a person is feeling faint but is not yet unconscious, they should lean forwards with their head between their knees or, ideally, lie down with their feet raised above the level of their head.
The aim of treatment is to get more blood and oxygen to the brain. Falling to the floor usually achieves this because the head is then at the same level as the heart. Once on the floor they should be put into the recovery position.
