Background: General anaesthesia is the state produced when a patient receivesmedications for amnesia, analgesia, muscle paralysis, and sedation. An anaesthetisedpatient can be thought of as being in a controlled, reversible state of unconsciousness. Anaesthesia enables a patient to tolerate surgical procedures that would otherwiseinflict unbearable pain, potentiate extreme physiologic exacerbations, andresult inunpleasant memories. General anaesthesia uses intravenous and inhaled agents toallowadequate surgical access to the operative site.