Bougies as an aid for endotracheal intubation with the Airway Scope: bench and manikin comparison studies

BACKGROUND When encountering a difficult airway with an Airway Scope (AWS) a bougie can be inserted into the endotracheal tube in the AWS channel. The angulated tip of the bougie can be guided toward the glottis by rotating it. We tested the ease of rotating bougies (Venn reusable, Boussignac, Portex single-use, and Frova) in an endotracheal tube when placed in the AWS channel. METHODS Bench study: Seven anesthesiologists inserted each of the four types of bougies into a 7.0 mm endotracheal tube in an AWS channel and rotated the bougie end (side of bougie operated by hand) clockwise or counterclockwise to an angle of 0°-180° in 45° increments. The rotation angle of the bougie tip (tracheal side) was measured for each bougie and the degree of force required to rotate them was examined. Manikin study: Using the same four bougies, the same seven anesthesiologists attempted to intubate a manikin that simulated a difficult airway. Success rate and time required for successful intubation were compared between the four bougies. RESULTS Bench study: The difference in the rotation angle between the bougie tip and end was significantly larger with Portex single-use and Frova bougies than with Venn reusable and Boussignac bougies (P < 0.01). The rotation angles of the tips of Venn reusable, Boussignac, Portex single-use, and Frova bougies were 145°/123° (clockwise / counterclockwise), 92°/108°, 46°/56°, and 39°/51°, respectively, when their ends were rotated to an angle of 180°. Venn reusable and Boussignac bougies could be rotated in the endotracheal tube by clinically acceptable rotational force. Manikin study: Times to intubation with Venn reusable [25 (SD, 5) s] and Boussignac bougies [35 (6) s] were significantly shorter than with Portex single-use [61 (17) s] and Frova bougies [69 (22) s] (P < 0.01). There were no significant differences in success rate between the four bougies. CONCLUSIONS Venn reusable and Boussignac bougies are a useful aid for intubation with an AWS. Portex single-use and Frova bougies seem to be less suitable for this technique. Different bougies may be of varying utility when used with an AWS or airway device with an endotracheal tube channel.