Influence of dextran on the absorption of adrenaline-containing lignocaine solutions: A protective mechanism in local anaesthesia

Abstract

Summary: The effect of adding 6% dextran to a lignocaine solution containing adrenaline was studied in 27 neurosurgicalpatients during modified neurolept-anaesthesia. Before trepanation they received infiltration anaesthesia of the scalp at the site of the proposed operation. For a period of 1 h following injection plasma concentrations of adrenaline were measured by high pressure liquid chromatography and serum concentrations of lignocaine by gas chromatography. The addition of dextran caused a significant reduction in the absorption of both adrenaline and lignocaine from the injection site. It is concluded that the dextran adjuvant constitutes a protective mechanism against toxic systemic side effects in local anaesthesia using adrenaline-containing anaesthetic solutions. This effect is particularly significant in patients with pre-existing cardiovascular disease and when local anaesthetic solutions are used in combination with volatile anaesthetics. © 1988 Copyright: 1988 British Journal of Anaesthesia.