Pharmacology of local anaesthesia in different age groups

Local anaesthetics are usually divided into amino-amides, drugs with a hepatic metabolism, and amino-esters, which are hydrolysed by esterases. Their effects are related to the inactivation of fast sodium channels. Although they have a large volume of distribution for local anaesthetics, neonates and infants have a low protein-binding capacity and a high heart rate. These conditions could increase the risk of bupivacaine cardiotoxicity. However, local anaesthetics have attractive pharmacodynamic characteristics in paediatric patients—such as easiness and safety of peripheral blocks and minor haemodynamic repercussion of central blocks.