title: Comparative analysis of airway scope and Macintosh laryngoscope for intubation primarily for cardiac arrest in prehospital setting.
abstract: OBJECTIVE
  This study sought to determine and compare the utility of the Airway scope (AWS; Pentax Corporation, Tokyo, Japan) and the conventional Macintosh laryngoscope (MLS) for intubation in the prehospital setting.
  
  
  METHODS
  In this randomized controlled trial in the prehospital setting, the primary outcome was time required for intubation, and the secondary outcomes were ultimate success, first attempt success, and difficulty of intubation. The intent-to-treat principle was used to analyze time to intubation. Ultimate success was defined as intubation completed within 600 s regardless of the device ultimately used.
  
  
  RESULTS
  A total of 109 patients, primarily with cardiac arrest, were randomly assigned to the AWS or MLS arms. Median time (interquartile range) to intubation was 155 (71-216) s with the AWS versus 120 (60-170) s with the MLS (P = .095). Ultimate success rate was slightly lower with the AWS (96.4%) than with the MLS (100%) (P = .496), while the first attempt success rate was significantly lower (46% and 75%, respectively; P = .002). There was no significant difference in difficulty of intubation (P = .066). Multivariate logistic regression analysis revealed that cervical immobilization and oral contamination, such as vomit, was associated with first attempt success (odds ratio [95% confidence interval]: 0.11 [0.01-0.87] and 0.43 [0.18-0.99], respectively).
  
  
  CONCLUSIONS
  Despite its many advantages seen in other settings, the AWS did not show superior efficacy to the MLS in relation to time required for intubation, ultimate or first attempt success rate, or difficulty level of intubation in the prehospital setting.
authors.affiliation: Emergency Department, Funabashi Municipal Medical Center. Electronic address: arimataka64@gmail.com.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Arima
authors.affiliation: Department of Anesthesiology, the Cancer Institute Hospital of JFCR, Tokyo, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Nagata
authors.affiliation: Emergency Department, Funabashi Municipal Medical Center.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Miura
authors.affiliation: Emergency Department, Funabashi Municipal Medical Center.
authors.forename: Katsuki
authors.initials: K
authors.lastname: Ikeda
authors.affiliation: Emergency Department, Funabashi Municipal Medical Center.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Mizushima
authors.affiliation: Emergency Department, Funabashi Municipal Medical Center.
authors.forename: Azusa
authors.initials: A
authors.lastname: Takahashi
authors.affiliation: Emergency Department, Funabashi Municipal Medical Center.
authors.forename: Koji
authors.initials: K
authors.lastname: Sakaida
mesh_terms: D000368:Aged; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D020704:Laryngoscopes / Q000592:standards; D008297:Male; D058687:Out-of-Hospital Cardiac Arrest / Q000628:therapy*; D013997:Time Factors