Comparison of glottic visualisation through supraglottic airway device (SAD) using bronchoscope in the ramped versus...

Airway management in obese patients is associated with increased risk of difficult airway and intubation. After failed intubation, supraglottic airway-guided flexible bronchoscopic intubation (SAGFBI) may be required. It is uncertain whether SAGFBI is best performed in the ramped versus conventional supine "sniffing air" position. We conducted a feasibility study to evaluate the logistics of positioning, compared glottic views, and evaluated SAGFBI success rates.

We conducted a prospective, pilot study in patients with a body mass index (BMI) 30-40 kg/m² undergoing elective operations requiring tracheal intubation. All patients were placed in a ramped position. After induction, a supraglottic airway device (SAD) was inserted. A flexible bronchoscope was inserted into the SAD and a photograph of the glottic view taken. The patient was repositioned to the supine position. A second photograph was taken. SAGFBI was performed. Images were randomised and assessed by two independent anesthetists.

Of 17 patients recruited, 15 patients were repositioned successfully. There were no differences in glottic views observed in the two positions. SAGFBI was successful in 92.9% of patients (median time 91.5 s). Haemodynamic changes were noted in 42.7% of patients which resolved spontaneously.

Our pilot study was completed within 5 months, achieved low dropout rate and protocol feasibility was established. SAGFBI was successfully and safely performed in obese patients, with a median time of 91.5 s. The time taken for SAGFBI was similar to awake intubation using FBI and videolaryngoscopy. Our study provided preliminary data supporting future, larger-scale studies to evaluate glottic views in the ramped versus supine positions.