Awake insertion of the laryngeal mask airway using topical lidocaine and intravenous remifentanil*

Abstract

We assessed the use of intravenous remifentanil for the insertion of the laryngeal mask airway in 10 healthy awake volunteers, a technique primarily developed to facilitate functional magnetic resonance imaging studies of anaesthesia. Each volunteer received 200 μg glycopyrronium intravenously. Topical airway anaesthesia was effected by 4 ml nebulised lidocaine 4%, followed by 12 sprays of lidocaine 10%. Remifentanil was subsequently infused to achieve an initial target effect‐site concentration of 2 ng.ml⁻¹; increments of 1 ng.ml⁻¹ were allowed with the maximum effect‐site concentration limited to 6 ng.ml⁻¹. Insertion of the laryngeal mask airway was successful on the first attempt in all cases. The median (IQR [range]) target effect‐site remifentanil concentration at insertion was 2.5 (2–3 [2–4]) ng.ml⁻¹. All volunteers were co‐operative during the procedure and only one reported discomfort. Sore throat was a complication in all volunteers. We conclude that the technique allows successful insertion of the laryngeal mask airway in healthy awake volunteers under conditions that were safe and reproducible.