Anaesthesia means ‘loss of sensation’. Medications that cause anaesthesia are called anaesthetics.
Anaesthetics are used during tests and surgical operations to induce sleep, which prevents pain and discomfort and enables a wide range of medical procedures to be performed. Local anaesthetics and general anaesthetics are two commonly used types of anaesthetics.
A local anaesthetic is often used during minor procedures where a small area of the body is numbed and you remain fully conscious.
A general anaesthetic is often used for more serious operations where you will be totally unconscious and unaware of the procedure.
How anaesthetics work
Anaesthetics work by blocking the signals sent along your nerves to your brain. Nerves are bundles of tiny fibres that use chemical and electrical signals to pass information around your body.
Anaesthetics work by stopping the nerve signals that keep you awake and aware from reaching your brain. During this state of induced sleep, procedures can be carried out without you feeling anything. After the anaesthetic has worn off, the nerve signals will be able to reach your brain, and consciousness and feeling will return.
Types of anaesthesia
As well as local and general anaesthetic, there are a number of other types of anaesthesia. Unlike general anaesthetic, these do not make you unconscious; they stop you feeling pain in a particular area of your body. The different types of anaesthetic are described below.
* Regional anaesthetic - this is a local anaesthetic given to a defined region of your body, usually served by a large nerve bundle (such as your arm), giving numbness or pain relief for deeper operations where more extensive numbness is needed.
* Epidural anaesthetic - a type of regional anaesthetic usually used to numb the lower half of the body and good for pain relief - for example, during labour and childbirth.
* Spinal anaesthetic - a type of regional anaesthetic used to give total numbness lasting...