The simplest form of anaesthesia is the local anaesthetic. The local anaesthetic drug is injected around a nerve, and the parts of the body supplied by the nerve are rendered anaesthetic. In its simplest form local anaesthetic can be injected just under the skin where the nerve endings are situated, as your doctor will do when stitching a cut.
There are many nerves that are accessible for local anaesthesia and these nerve blocks can be used to operate on the arms, legs and other parts of the body.
Because the dose of local anaesthetic is controlled and it is injected around the nerve and not into the bloodstream, the heart and brain are not exposed to the drug. This makes local anaesthesia a very safe procedure.
The effect of local anaesthesia on the body: