A clinical comparison of the Flexiblade™ and Macintosh laryngoscopes for laryngeal exposure in anesthetized adults

Abstract

The Flexiblade™ is a laryngoscope with a flexible blade. To evaluate the efficacy of the Flexiblade™ compared with the classic Macintosh laryngoscope, we performed a clinical study in 200 paralyzed patients undergoing elective surgery requiring general anesthesia and endotracheal intubation. Direct laryngoscopy was performed with a size 3 Macintosh laryngoscope and the Flexiblade™, with and without activation of the lever. The laryngeal views were recorded, without manipulation, according to the Cormack and Lehane classification. No laryngoscopic view obtained by the Macintosh blade was worse than that obtained by the Flexiblade™ without the lever activated. The Macintosh blade improved 58.5% of non-Grade I views obtained by the Flexiblade™ with its lever not activated. However, when the Flexiblade™ lever was activated, 39.6% of non-Grade I views obtained by the Macintosh blade were improved, whereas 84.5% of non-Grade I views obtained by the inactivated Flexiblade™ were improved. Activating the Flexiblade™ lever never caused a deterioration of view. In only one case was the view better with the Macintosh blade than that with the activated Flexiblade™. We conclude that the Flexiblade™, after lever activation, is significantly better than the Macintosh laryngoscope for laryngeal visualization in paralyzed adults (P < 0.0001). ©2006 by the International Anesthesia Research Society.