title: Cardiac arrest is a predictor of difficult tracheal intubation independent of operator experience in hospitalized patients.
abstract: BACKGROUND
  Placement of advanced airways has been associated with worsened neurologic outcome in survivors of out-of-hospital cardiac arrest. These findings have been attributed to factors such as inexperienced operators, prolonged intubation times and other airway related complications. As an initial step to examine outcomes of advanced airway placement during in-hospital cardiac arrest (IHCA), where immediate assistance and experienced operators are continuously available, we examined whether cardiopulmonary resuscitation efforts affect intubation difficulty. Additionally, we examined whether or not the use of videolaryngoscopy increases the odds of first attempt intubation success compared with traditional direct laryngoscopy.
  
  
  METHODS
  The study setting is a large urban university-affiliated teaching hospital where experienced airway managers are available to perform emergent intubation for any indication in any out-of-the-operating room location 24 hours a day, 7 days-a-week, 365 days-a-year. Intubations occurring in all adults >18 years-of-age who required emergent tracheal intubation outside of the operating room between January 1, 2008 and December 31, 2012 were examined retrospectively. Multivariate logistic regression was used to estimate the odds of difficult intubation during IHCA compared to other emergent non-IHCA indications with adjustment for a priori defined potential confounders (body mass index, operator experience, use of videolaryngoscopy versus direct laryngoscopy, and age).
  
  
  RESULTS
  In adjusted analyses, the odds of difficult intubation were higher when taking place during IHCA (OR=2.63; 95% CI 1.1-6.3, p=0.03) compared to other emergent indications. Use of video versus direct laryngoscopy for initial intubation attempts during IHCA, however, did not improve the odds of success (adjusted OR = 0.71; 95% CI 0.35-1.43, p = 0.33).
  
  
  CONCLUSIONS
  Difficult intubation is more likely when intubation takes place during IHCA compared to other emergent indications, even when experienced operators are available. Under these conditions, direct laryngoscopy (versus videolaryngoscopy) remains a reasonable first choice intubation technique.
authors.affiliation: University of Washington, Harborview Medical Center, 325 Ninth Avenue, Box 359724, Seattle, WA 98104, USA.
authors.forename: Nita
authors.initials: N
authors.lastname: Khandelwal
authors.affiliation: University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Galgon
authors.affiliation: Northeast Ohio Medical University, School of Medicine, Rootstown, OH, USA.
authors.forename: Marwan
authors.initials: M
authors.lastname: Ali
authors.affiliation: University of Washington, Harborview Medical Center, 325 Ninth Avenue, Box 359724, Seattle, WA 98104, USA.
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Joffe
mesh_terms: D000328:Adult; D000368:Aged; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D002983:Clinical Competence; D005260:Female; D006323:Heart Arrest / Q000628:therapy*; D006785:Hospitals, University; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods*; D007828:Laryngoscopy / Q000379:methods*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D020535:Video-Assisted Surgery / Q000379:methods
keywords: Direct laryngoscopy; In-hospital cardiac arrest; Intubation; Videolaryngoscopy