Airway Assessment

Figure 5. Passage of a bevel-tipped ETT through the glottis with an accentuated
secondary curve.
The C-Mac video laryngoscope TM has blades designed to either follow (the “Dorges” or D blade)
or compress the airway curves (the modified Macintosh blade). Use of the modified Macintosh
blade in patients with posterior column pathology permits flattening of the primary and
secondary curves, with the benefit of video-assisted glottic visualisation from further along the
primary curve. Consequently, the operator may need to apply less force to visualise the glottis
compared to a standard Macintosh blade. The C-Mac TM should improve intubating conditions
compared to contouring video laryngoscope blades, due to flattening of the secondary curve
(anti-clockwise rotation of the laryngeal vestibule axis). The application of this device is intuitive,
and it is recommended to operators with infrequent exposure to video laryngoscopes.
The Classic LMA TM (cLMA, LMA North America, Inc, US) with fibreoptic bronchoscope/Aintree
Intubating Catheter TM18 (AIC; Cook Critical Care, US), intubating laryngeal mask 19-21 and
flexible fibreoptic intubation are other possible alternatives. Intubation can be assisted via the
placement of a Classic LMA TM in the extraglottic region, permitting oxygenation +/- ventilation.
Subsequently, a fibreoptic bronchoscope loaded with an AIC TM is inserted through the LMA until
the glottis is visualised (Figure 6). Once the AIC TM positioned in the trachea under fibreoptic
vision, the cLMA TM and the bronchoscope are removed. Intubation with an ETT over the AIC TM
is facilitated with a curved-blade laryngoscope to flatten the primary and secondary curves.
53 Airway Assessment