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Updated: Feb 15, 2026

Repeated Orotracheal Intubation in Mice
Published on: March 27, 2020
Stylet angulation of 70 degrees reduces the time to intubation with the GlideScope®: A prospective randomised trial
Yong-Cheol Lee1, Jiwon Lee1, Je-Do Son1
1Department of Anaesthesiology and Pain Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea.
Abstract:
Objective The GlideScope® videolaryngoscope provides a good view of the glottis. However, directing and inserting an endotracheal tube is sometimes difficult during intubation with the GlideScope®. In this study, we compared two GlideScope® stylet angulations (90° vs. 70°) in terms of the time to intubation. Methods In total, 162 patients scheduled for elective surgery under general anaesthesia were randomly assigned to one of two groups. In the 90 group ( n = 79), a 90° stylet was used. In the 70 group ( n = 78), a 70° stylet was used. The time to intubation was recorded. The number of intubation attempts was assessed. Results The time to intubation was significantly shorter in the 70 than 90 group [26.0 (23.0-32.0) vs. 37.0 (30.0-43.0) s, respectively]. The first-time intubation success rate was significantly higher and the number of failed intubations was significantly lower in the 70 than 90 group (100% vs. 87% and 0% vs. 6%, respectively). Conclusions This investigation suggests that a 70° angle stylet is superior to a 90° angle stylet for GlideScope® intubation. Trial Registration Clinicaltrials.gov Identifier: NCT02547064.
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