Plasma lignocaine levels during paediatric endoscopy of the upper respiratory tract

Abstract
Summary: Plasma lignocaine levels were measured at 5, 10 and 15 minutes following local application (4 mg/kg) to the upper airway in children who underwent endoscopy under general anaesthesia. These levels were then correlated with the appearance of the moistness of the airway mucosa secondary to premedication with atropine. This latter assessment was carried out by one anaesthetist who used a predetermined scale of 1–5, where I was very dry and 5 very wet. Significantly higher (p < 0.05) plasma levels of lignocaine were achieved when the mucosa was ‘very dry’ especially in children under 2 years of age. The total dose of lignocaine applied to the upper airway of children should probably be reduced, in the presence of a ‘dry’ mucosa after effective antisialogogue premedication, and especially when less than 2 years of age.