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

Abstract

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.