Toxicity of Local Anaesthetics in Obstetrics I: Bupivacaine—Research and Clinical Aspects

SUMMARY

Bupivacaine is a widely used local anaesthetic of the amino amide class that is relatively free of side-effects if it is administered in an appropriate dosage and in the appropriate anatomical location. Toxic systemic reactions to bupivacaine and other local anaesthetics are largely restricted to the central nervous and cardiovascular systems. The acid-base status of the patient, the time course to peak blood concentration, and the relative potency of the local anaesthetic have correlated with ability to produce CNS symptomatology. The clinical impression that bupivacaine possesses unusual cardiotoxic properties has been demonstrated in laboratory animals. Neonatal effects appear to be minimal. The principles of safe use have been outlined. Bupivacaine is a very useful local anaesthetic in obstetrics and can be used safely, but it is not perfect. The search for new drugs with minimal systemic toxicity and bupivacaine-like efficacy continues.