Comparison of Two Different Shapes of Stylets for Intubation with the McGrath MAC®: A Randomized Controlled Trial

Abstract

Background: Adequate shapes for videolaryngoscopes are important for safer, faster, and successful intubation. The aim of this study was to compare two different shapes of stylets, the 60º and J-shape stylets, for intubation with the McGrath MAC®. Methods: In this multicenter, prospective, randomized controlled study, patients undergoing elective surgery under general anesthesia were randomly assigned into the 60º group or the J group. After anesthetic induction, subjects in both groups were intubated with an endotracheal tube bent into a specific shape according to the group allocation. Time to intubation, difficulty of intubation, glottic view grade, use of external manipulation, and number of intubation attempts were recorded. Results: One hundred and eight patients in the J group and 110 patients in the 60º group were enrolled. Time to intubation in the J group [23.1 (20.6-28.0)] was not different from the 60º group [24.8 (20.5-28.3), P = 0.623). There were no differences in difficulty of intubation, glottic view grade, use of external manipulation, and number of intubation attempts between the two groups. Conclusions: Adding extra curvature to the tube to resemble the shape of the blade did not improve the intubation conditions of the McGrath MAC®.