A comparison of the force applied on oral structures during intubation attempts between the Pentax-AWS airwayscope and the Macintosh laryngoscope: a high-fidelity simulator-based study

Objective: We sought to determine whether the use of Pentax-AWS Airwayscope (AWS) applied less force on oral structures during intubation attempts than a conventional direct laryngoscope (DL).

Design: Prospective cross-over study.

Participants: A total of 37 physicians (9 transitional-year residents, 20 emergency medicine residents and 8 emergency physicians) were enrolled.

Interventions: We used four simulation scenarios according to the difficulty of intubation and devices and used a high-fidelity simulator to quantify the forces applied on the oral structures.

Outcome measures: Primary outcomes were the maximum force applied on the maxillary incisors and tongue. Other outcomes of interest were time to intubation and glottic view during intubation attempts.

Results: The maximum force applied on the maxillary incisors in the normal airway scenario was higher with the use of AWS than that with DL (107 newton (N) vs 77 N, p=0.02). By contrast, the force in the difficult airway scenario was significantly lower with the use of AWS than that of the DL (89 N vs 183 N, p<0.01). Likewise, the force applied on the tongue was significantly lower with the use of AWS than the use of DL in both airway scenarios (11 N vs 27 N, p<0.001 in the normal airway scenario; 12 N vs 40 N, p<0.01 in the difficult airway scenario).

Conclusions: The use of AWS during intubation attempts was associated with decreased forces applied to oral structures in the simulated difficult airway scenario.