Akademik

loss of feeling or sensation in a part or all of the body. Anaesthesia of a part of the body may occur as a result of injury to or disease of a nerve; for example in leprosy. The term is usually applied, however, to the technique of reducing or abolishing an individual's sensation of pain to enable surgery to be performed. This is effected by administering drugs (see anaesthetic) or by the use of other methods, such as acupuncture or hypnosis.

General anaesthesia is total unconsciousness, usually achieved by administering a combination of injections and gases (the latter are inhaled through a mask). Local anaesthesia abolishes pain in a limited area of the body and is used for minor operations, particularly many dental procedures. It may be achieved by injections of substances such as lidocaine (commonly used in dentistry) close to a local nerve, which deadens the tissues supplied by that nerve. Local anaesthesia may be combined with intravenous sedation. An appropriate injection into the spinal column produces spinal anaesthesia or epidural anaesthesia in the lower limbs or abdomen. Regional anaesthesia, usually of a limb, is achieved by encircling local anaesthetic solutions or direct application of anaesthetic to one or more peripheral nerves.