What is anaesthesia?
Anaesthesia is defined as “Loss of sensation” (Oxford English Dictionary). Anaesthesia can be produced either by blocking sensation to a particular region of the body (local or regional anaesthesia) or by the administration of drugs that produce a loss of consciousness (general anaesthetics). Most laboratory animals are anaesthetised using general anaesthetics, but local anaesthesia can also be useful. For example, local anaesthetic cream (EMLA, Astra) can be applied to the skin to prevent pain or discomfort associated with venepuncture.