Dental Strain on Maxillary Incisors During Tracheal Intubation With Double-Lumen Tubes and Different Laryngoscopy Techniques - A Blinded Mannequin Study

Objectives: To quantify dental forces during double-lumen tube intubations with different laryngoscopy techniques. Design: Experimental biomechanical mannequin study. Setting: Two German university hospitals. Participants: One hundred four anesthesiologists with varying levels of experience. Interventions: Participants performed a sequence of intubations on a mannequin equipped with hidden forces sensors in the maxillary incisors. Different laryngoscopy techniques were evaluated under normal and difficult airway conditions. Direct laryngoscopy was compared with different videolaryngoscopy techniques: the C-MAC with a Macintosh blade, the GlideScope, and the KingVision with hyperangulated blades. Measurements and Main Results: A total of 624 intubations were evaluated. In normal airway conditions, the median (interquartile range [range]) peak forces were significantly lower when the GlideScope (15.7 (11.3-22.0 [2.1-110.5]) N) was used compared with direct laryngoscopy (21.0 (14.1-28.5[4.7-168.6]) N) (p = 0.007). In difficult airways, resulting forces were reduced using hyperangulated videolaryngoscopes (Glide-Scope: -13.7 N [p < 0.001]; KingVision: -11.9 N [p < 0.001]) compared with direct laryngoscopy, respectively. The time to intubation was prolonged with the use of the KingVision (25.5 (17.1-41.9[9.2-275.0])s [p < 0.001]) in comparison to direct laryngoscopy (20.8 (15.9-27.4[8.7-198.6]) s). The C-MAC demonstrated the shortest time to intubation. Conclusions: Although hyperangulated videolaryngoscopes improve dental strain, clinicians also should consider the time to intubation, which is shortest with nonhyperangulated videoblades, when choosing a laryngoscopy technique on an individual patient basis. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

The study quantified dental forces during double-lumen tube intubations with different laryngoscopy techniques. The results showed that while videolaryngoscopes reduced dental strain, they also prolonged the time to intubation. Different laryngoscopy techniques performed differently under normal and difficult airway conditions.