This study compared remifentanil and dexmedetomidine as awake fiberoptic intubation (AFOI) anesthetics. Thirty-four adult ASA I-III patients were enrolled in a double-blinded randomized pilot study to receive remifentanil (REM) or dexmedetomidine (DEX) for sedation during AFOI (nasal and oral). Thirty patients completed the study and received 2？mg midazolam IV and topical anesthesia. The REM group received a loading dose of 0.75？mcg/kg followed by an infusion of 0.075？mcg/kg/min. The DEX group received a loading dose of 0.4？mcg/kg followed by an infusion of 0.7？mcg/kg/hr. Time to sedation, number of intubation attempts, Ramsay sedation scale (RSS) score, bispectral index (BIS), and memory recall were recorded. All thirty patients were successfully intubated by AFOI (22 oral intubations/8 nasal). First attempt success rate with AFOI was higher in the REM group than the DEX group, 72% and 38% ( ), respectively. The DEX group took longer to attain RSS of ≥3 and to achieve BIS <80, as compared to the REM group. Postloading dose verbal recall was poorer in the DEX group. Dexmedetomidine seems a useful adjunct for patients undergoing AFOI but is dependent on dosage and time. Further studies in the use of dexmedetomidine for AFOI are warranted. 1. Introduction Awake nasal or oral flexible fiberoptic intubation (AFOI) is usually the primary method for airway management in the expected difficult airway. Experience with AFOI is not easily acquired, and success of the procedure is also highly dependent on adequate preparation and sedation techniques, especially in training programs [1]. Optimal conditions for AFOI include that a patient be comfortable, cooperative, free of oropharyngeal blood and secretions, and able to maintain their airway with spontaneous ventilation. In order to achieve these conditions, the pharmacologic agent chosen for sedation should be short acting, easily titratable, provide the required amount of sedation and have little suppression of spontaneous ventilation. Controlled sedation and analgesia are paramount to AFOI, but deep sedation can result in loss of the airway with serious consequences. Techniques to improve success rate have included nasal over oral intubation (not always possible or not indicated in studies) and different protocols for sedation (sevoflurane, propofol and remifentanil with titrated or target controlled infusion) [1–9]. There have been numerous reports of remifentanil and propofol used either alone or in combination to achieve an adequate level of sedation for such procedures. The advantages of remifentanil for
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