Date Published: July 16, 2012
Publisher: Hindawi Publishing Corporation
Author(s): Davide Cattano, Nicholas C. Lam, Lara Ferrario, Carmen Seitan, Kash Vahdat, Darrell W. Wilcox, Carin A. Hagberg.
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% (P = 0.02), 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.
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 .
During the years 2006 and 2007, after institutional review board approval from the University of Texas Medical School at Houston, written informed consent was obtained from 34 adult ASA I-III patients who required AFOI, as deemed necessary by the attending anesthesiologist. Due to case cancellations or delays, only 30 patients were included. These patients were randomized by the pharmacy into one of two groups: group REM (remifentanil) and group DEX (dexmedetomidine). Study drugs were prepared by the pharmacy in accordance to the patient’s weight in kilograms and blinded to the anesthesia care team (faculty and resident) and the patient. All residents were CA-2 or CA-3 and had previously performed at least 5 oral and 5 nasal fiberoptic intubations. Their classification as “trainee” anesthesiologists provided the study with insight into how the “average” anesthesiologist (i.e., a mid-level provider not employed at a tertiary level hospital) would perform and which drug would be of more value to him. No stratification was decided between oral and nasal intubations.
Thirty randomized cases underwent awake fiberoptic intubation; 17 were in the REM group and 13 were in the DEX group. Unequal distribution resulted due to a prerandomized list that did not adjust for the four excluded DEX patients. AFOI was successful in all patients in both groups. Five patients in the REM group and 3 patients in the DEX group received nasal endotracheal intubation.
The current study showed relatively similar efficacy of Dexemedetomidine and remifentanil as adjuvant to endotracheal oral and nasal intubation. The study ended being underpowered by 4 patients in the DEX group.
Mid-level providers of anesthesia will find it of more benefit to use remifentanil for awake fiberoptic intubation.