Comfortably numb

If large areas need to be anaesthetised while the patient is still awake, local anaesthetics can be injected around nerve bundles. By preventing transmission through a large nerve, the signals from all the smaller nerves that feed into it can’t reach the brain. Injecting anaesthetic around the maxillary nerve will not only generate numbness in the roof of the mouth and the teeth on that side, but will stop transmission from the nose and sinuses too. Local anaesthetics can also be injected into the epidural space in the spinal canal. This prevents transmission through the spinal roots, blocking the transmission of information to the brain.