Tracheal intubation using Bullard laryngoscope for patients with a simulated difficult airway

To evaluate the utility and safety of orotracheal intubation in adult patients with simulated difficult airways using the Bullard Laryngoscope (BL).

A rigid cervical collar was used to simulate the difficult airway. The study consisted of two phases. Phase I evaluated the BL used in conjunction with an independently styletted endotracheal tube (ISETT) passed freehand into the trachea. Phase II evaluated the new Multifunctional Intubating Stylet (MFIS). Forty patients were studied in each phase. Following induction of anesthesia a rigid cervical collar was applied and the laryngoscopic grade assessed. Tracheal intubation was then performed using the BL with either an ISETT or the MFIS. The total time to intubate, number of attempts, failures, hemodynamic changes during intubation were recorded.

The rigid collar effectively simulated a difficult laryngoscopy, 65% of patients had a grade 3 view. The success rates for tracheal intubation using the ISETT and MFIS were 88% and 83% respectively. The average times to intubation were similar for both intubating techniques (45.4 +/- 26.8 sec for the ISETT and 41.2 +/- 25.2 sec for the MFIS). Although there were minor hemodynamic changes, mucosal bleeding and sore throat following intubation, there were no major complications in any of the study patients.

The BL, used with either an ISETT or the MFIS, is an effective and safe intubating device for patients with simulated restricted cervical spine movement. Further studies are needed to compare the effectiveness and safety of these two techniques in managing patients with a difficult airway.