Local anaesthesia and its safe use in minor surgery

Abstract

Local anaesthetics are drugs that are used clinically to produce reversible inhibition of excitation and conduction in peripheral nerve fibres and produce loss of sensation in a circumscribed area of the body. Local anaesthetics have a common structure (Figure 1) with a lipophilic (aromatic) group joined to a hydrophilic (amine) group by an intermediate chain. This intermediate chain may be either an amide or ester link, hence the two major groups of local anaesthetics are esters and amides (Figure 2). The linkage is important because of the metabolism of that group which has, in the case of esters, led to adverse reactions and limited their use. Knowledge of the physicochemical prop-Local anaesthesia and its safe use in minor surgery erties of a local anaesthetic is important as they influence the pharmacodynamics of that drug.