Review of local anaesthetic agents.

The currently available local anaesthetic agents are capable of providing high quality nerve blockade in a wide variety of clinical circumstances. Our understanding of the mechanisms and consequences of toxicity is increasing rapidly. Knowledge of the chemistry of local anaesthetics has enabled clinicians to exploit the increased safety of single isomer agents. However, the extent, if any, of this improvement in toxicity has yet to be proven. Established toxicity may be very difficult to treat and no specific reversing therapy is yet available. Until this occurs it is essential that practitioners of regional anaesthesia maintain their knowledge base and skill in techniques of administration of local anaesthetic, are able to recognise impending disaster, and constantly update their skills in resuscitation.