Intravenous versus Nebulized Dexmedetomidine for Awake Fiberoptic Bronchoscopy in Head and Neck Cancer Surgery: A Randomized Double-Blind Comparative Study

Background: Awake fiberoptic intubation is the technique of choice when the airway is anticipated to be difficult, as it commonly is in head and neck cancer. Dexmedetomidine sedates well without depressing respiration, but the intravenous route is prone to bradycardia and hypotension. Nebulization offers topical airway anaesthesia with slower systemic uptake and may avoid these swings. We compared the two routes at an equivalent dose. Material and Methods: In this prospective, randomized, double-blind study, 86 adults (ASA II–III) undergoing head and neck cancer surgery with awake fiberoptic nasotracheal intubation were allocated to intravenous dexmedetomidine 1 µg/kg over 20 minutes with saline nebulization (Group I, n=43) or saline infusion with nebulized dexmedetomidine 1 µg/kg (Group N, n=43). Sedation, cough and vocal cord scores, patient tolerance, intubation time, haemodynamics, satisfaction, and adverse events were recorded. Results: Heart rate and mean arterial pressure were lower in Group I from 10 minutes through 60 minutes post-intubation (p<0.05). Sedation was deeper (median RSS 3 vs 2; p<0.001), cough better suppressed (no cough in 65.1% vs 27.9%; p<0.001), and intubation faster (52.4±8.6 vs 78.9±14.2 s; p<0.001). Excellent satisfaction was reported by 65.1% vs 32.6% (p<0.001). Bradycardia and hypotension were more frequent in Group I (p=0.044 and 0.049). Oxygenation was preserved in both. Conclusion: Intravenous dexmedetomidine gave better sedation, intubating conditions, comfort, and procedural speed, at the cost of more haemodynamic adverse effects. The nebulized route is a gentler alternative when haemodynamic stability is paramount.

Keywords: Dexmedetomidine; awake fiberoptic intubation; head and neck cancer; nebulization; difficult airway; sedation.