A Comparison Between the Bonfils Intubation Fiberscope and McCoy Laryngoscope for Tracheal Intubation in Patients with a Simulated Difficult Airway

Abstract

The Bonfils Intubation Fibrescope (Bonfils) and the McCoy laryngoscope (McCoy) are airway devices designed to assist tracheal intubation in difficult cases. Individually, both the Bonfils and McCoy have demonstrated superiority to the Macintosh laryngoscope in a simulated difficult airway. In this study, we compared the Bonfils with the McCoy laryngoscope in patients whose tracheal intubation had been intentionally hindered. Our primary hypothesis was that there is a significant difference in the rate of success for tracheal intubation when using the Bonfils or McCoy laryngoscope in patients with an intentionally hindered airway. Patients undergoing elective surgery and requiring general anesthesia and endotracheal intubation were randomized to have intubation performed with either the Bonfils or McCoy laryngoscope. All patients were fitted with a hard cervical collar to simulate a difficult airway. Data collected included the success rate of endotracheal intubation, the time taken for intubation, the number of attempts required, the use of further aids to intubation, hemodynamic variables, and the incidence of adverse events. The primary end point was the relative rate of successful tracheal intubation. Categorical outcome measures were compared using the χ test, or Fisher exact test where appropriate, and the Mann-Whitney U test or unpaired Student t test where data were continuous. For the nonnormally distributed data, log transformation was adopted, and t test was performed if normalcy was achieved. Sixty adult patients were recruited and randomized into 2 groups of 30 patients each. There was no difference in the rate of successful intubation between groups (95% confidence interval [CI], -11.6% to 11.6%), with a 100% success rate achieved in both groups. We found no statistically significant differences between groups in the time taken for intubation (P = 0.32, 95% CI, 0.90-1.41) and percentage of single attempts (P = 0.47, 95% CI, -30.3% to 9.7%). However, further aids to intubation were required more frequently when using the McCoy laryngoscope (P < 0.001, 95% CI, 0.17-0.46), with 18 patients in the McCoy group requiring the use of an elastic bougie, and no patients in the Bonfils group requiring any aids. There were no significant differences found in the rates of adverse events. In the hands of trained operators, there appears to be no clinically significant difference in success, time to intubation, or adverse outcomes, when comparing the Bonfils with the McCoy laryngoscope, in the setting of a simulated difficult airway. The choice to use either device should remain based on appropriate patient selection, available aids, individual operator's experience, and economic circumstances.