Development of the obstetric unanticipated difficult video-laryngoscopy algorithm through a quality improvement randomized open-label in situ simulation study

Background: Video-laryngoscopy is increasingly used during general anesthesia for emergency cesarean deliveries. Given the heightened risk of difficult tracheal intubation in obstetrics, addressing challenges in airway management is crucial. In this simulation study, we hypothesized that using a flexible bronchoscope would lead to securing the airway faster than the Eschmann introducer when either device is used in addition to video-laryngoscopy.

Methods: Twenty-eight anesthesia trainees (n=14/group) were randomized to use either one of the rescue devices and video-recorded in a simulated scenario of emergency cesarean delivery. The primary outcome was the time difference in establishing intubation; secondary outcomes were the differences in incidence of hypoxemia, need for bag and mask ventilation, and failed intubation between the two rescue devices.

Results: Mean (±SD) time to intubation using flexible bronchoscopy was shorter compared to using an Eschmann introducer (24 ± 10 vs 86 ± 35 s; P<0.0001; difference in mean 62 seconds, 95% CI 42 to 82 seconds). In the fiberoptic bronchoscopy group, there were no episodes of hypoxemia or need for bag and mask ventilation; in contrast both such events occurred frequently in the Eschmann introducer group (71%, 10/14); P=0.0002). All flexible bronchoscopy-aided intubations were established on the first attempt. The incidence of failed intubation was similar in both groups.

Conclusions: Our data from simulated emergency tracheal intubation suggest that flexible bronchoscopy combined with video-laryngoscopy results in faster intubation time than using an Eschmann introducer combined with video-laryngoscopy.