title: 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).
  
  
  METHODS
  Prospective cross-over study.
  
  
  METHODS
  A total of 37 physicians (9 transitional-year residents, 20 emergency medicine residents and 8 emergency physicians) were enrolled.
  
  
  METHODS
  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.
  
  
  METHODS
  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.
authors.affiliation: Department of Emergency Medicine, University of Fukui Hospital, Fukui, Japan.
authors.forename: Tadahiro
authors.initials: T
authors.lastname: Goto
authors.affiliation: Department of Emergency and Critical Care Medicine, University of Tsukuba Hospital, Ibaraki, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Koyama
authors.affiliation: Department of Healthcare Epidemiology, Graduate School of Medicine and Public Health, Kyoto University, Kyoto, Japan.
authors.forename: Takashiro
authors.initials: T
authors.lastname: Kondo
authors.affiliation: Harvard Interfaculty Initiative in Health Policy, Harvard University, Cambridge, Massachusetts, USA.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Tsugawa
authors.affiliation: Department of Emergency Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Kohei
authors.initials: K
authors.lastname: Hasegawa
mesh_terms: D002983:Clinical Competence; D018592:Cross-Over Studies; D004635:Emergency Medicine; D004867:Equipment Design; D006801:Humans; D007180:Incisor; D007396:Internship and Residency; D007442:Intubation, Intratracheal; D020704:Laryngoscopes; D008348:Manikins; D008953:Models, Anatomic; D011312:Pressure; D011446:Prospective Studies; D014059:Tongue
keywords: ACCIDENT & EMERGENCY MEDICINE