The efficacy and safety of EMLA (R) Cream for awake fiberoptic endotracheal intubation

EMLA(R) Cream (EC; Astra, Westborough, MA) has been widely used as a local anesthetic. Limited safety information is available with respect to the app lication of EC to the oral mucous membranes. The purpose of this pilot stud y was to evaluate the efficacy and safety of EC when applied to oral mucosa for fiberoptic intubation. Twenty ASA physical status I-IV patients (11 wo men and 9 men), 28-57 yr old, who were scheduled for awake, fiberoptic, int ubation participated in this open-label study. A total of 4 g of EC was use d for 5 min until the patient showed no evidence of a gag reflex (this was evaluated clinically by the patient's acceptance of the William's airway an d considered the endpoint for assessing adequate topicalization of the orop harynx). The measured peak plasma concentration of lidocaine or prilocaine did not reach toxic levels in any patient. Methemoglobin levels did not exc eed normal values (1.5%) in any patient, and there was no relationship betw een methemoglobin levels and patient weight, amount of EC used, measured pe ak plasma concentration, or times to measured peak concentrations of priloc aine or lidocaine. We conclude that EC provided satisfactory topical anesth esia allowing for successful oral fiberoptic intubation in all patients and should be considered a safe alternative for anesthetizing the airway of pa tients requiring awake oral fiberoptic intubation.