Effects of the jaw-thrust manoeuvre in the semi-sitting position on securing a clear airway during fibreoptic intubation

Securing a clear airway is important for successful fibreoptic intubation. We investigated whether the jaw-thrust manoeuvre in the 25 degrees semi-sitting position improves airway clearance compared with the supine position in 88 anaesthetised patients randomly assigned to the two positions. After induction of anaesthesia, the fibreoptic bronchoscope was advanced into the mouth along the dorsum of the tongue during the jaw-thrust manoeuvre. Airway clearance was assessed at the level of the soft palate and epiglottis. Patients in the 25 degrees semi-sitting position had clearer airways (judged subjectively by a three-level scale) than those in the supine position at the soft palate level (p=0.012). At the level of the epiglottis, airway clearance was equally good in both positions. The mean (SD) times to view the vocal cord and carina were shorter in the 25 degrees semi-sitting position (4 (1) s and 8 (1) s, respectively) compared with the supine position (6 (3) s and 11 (3) s; p<0.001, respectively). The time to achieve intubation was also shorter in the 25 degrees semi-sitting position (21 (5) s) than in the supine position (25 (7) s; p=0.018).