title: Difficult intubation and outcome after out-of-hospital cardiac arrest: a registry-based analysis.
abstract: BACKGROUND
  Airway management during resuscitation attempts is pivotal for treating hypoxia, and endotracheal intubation is the standard procedure. This German Resuscitation Registry analysis investigates the influence of airway management on primary outcomes after out-of-hospital cardiac arrest, in a physician-based emergency system.
  
  
  METHODS
  A total of 8512 patients recorded in the German Resuscitation Registry (2007-2011) were analyzed. The Return of Spontaneous Circulation After Cardiac Arrest (RACA) score was used to compare observed return of spontaneous circulation (ROSC) rates with the ROSC predicted by the score and to analyze factors influencing the primary outcome. Patients were classified into three groups: difficult intubation, impossible intubation, and a control group with normal airways.
  
  
  RESULTS
  The observed ROSC matched the predicted ROSC in the group with difficult airways. The impossible intubation group had lower ROSC rates (31.3% vs. 40.5%; P < 0.05). Impossible intubation was more frequent in men (OR 2.28; 95% CI, 1.43-3.63; P = 0.001), young patients (OR 2.18; 95% CI, 1.26-3.76; P = 0.005) and those with trauma (OR 2.22; 95% CI, 1.01-4.85; P = 0.046). Fewer impossible intubations were reported when the emergency physicians were anesthesiologists (OR 0.65; 95% CI, 0.44-0.96; P = 0.028). If a supraglottic airway device was not used in the impossible intubation group, the observed ROSC (18.0%; 95% CI, 7.4-28.6%) was poorer than predicted (38.2%) (P < 0.05).
  
  
  CONCLUSIONS
  Outcomes after resuscitation attempts are poorer when endotracheal intubation is not possible. Predictive factors for impossible intubation are male gender, younger age, and trauma. Supraglottic airway devices should be used at an early stage whenever these negative factors are present.
authors.affiliation: Department of Anesthesiology and Intensive-Care Medicine, University Medical Center Schleswig-Holstein, Campus Luebeck, Ratzeburger Allee 160, Haus 13, 23538, Luebeck, Germany. wnent@reanimationsregister.de.
authors.forename: Jan
authors.initials: J
authors.lastname: Wnent
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, European Medical School Oldenburg-Groningen, Oldenburg, Germany. ruediger_franz@t-online.de.
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Franz
authors.affiliation: Department of Anesthesiology and Intensive-Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Schwanenweg 21, 24105, Kiel, Germany. seewald@reanimationsregister.de.
authors.forename: Stephan
authors.initials: S
authors.lastname: Seewald
authors.affiliation: University of Witten/Herdecke, Faculty of Medicine, Institute for Research in Operative Medicine, Ostmerheimer Strasse 200, Haus 38, 51109, Cologne, Germany. rolf.lefering@uni-wh.de.
authors.forename: Rolf
authors.initials: R
authors.lastname: Lefering
authors.affiliation: Department of Anesthesiology and Intensive-Care Medicine, Klinik am Eichert, ALB.Fils-Kliniken, Eichertstrasse 3, 73035, Göppingen, Germany. Matthias.Fischer@af-k.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Fischer
authors.affiliation: City of Münster, Fire Department, York-Ring 25, 48159, Münster, Germany. BohnA@stadt-muenster.de.|Department of Anesthesiology and Intensive-Care Medicine, Münster University Hospital, Albert-Schweitzer-Campus 1, Gebäude A1, 48149, Münster, Germany. BohnA@stadt-muenster.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bohn
authors.affiliation: Institute for Prevention and Occupational Medicine, Ruhr-Universität Bochum, Buerkle de la Camp-Platz 1, 44789, Bochum, Germany. walther@ipa-dguv.de.
authors.forename: Jörg W
authors.initials: JW
authors.lastname: Walther
authors.affiliation: Department of Anesthesiology and Intensive-Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Schwanenweg 21, 24105, Kiel, Germany. vv@uksh.de.
authors.forename: Jens
authors.initials: J
authors.lastname: Scholz
authors.affiliation: Department of Anesthesiology and Intensive-Care Medicine, Münster University Hospital, Albert-Schweitzer-Campus 1, Gebäude A1, 48149, Münster, Germany. lukasr@uni-muenster.de.
authors.forename: Roman-Patrik
authors.initials: RP
authors.lastname: Lukas
authors.affiliation: Department of Anesthesiology and Intensive-Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Schwanenweg 21, 24105, Kiel, Germany. graesner@reanimationsregister.de.
authors.forename: Jan-Thorsten
authors.initials: JT
authors.lastname: Gräsner
mesh_terms: D058109:Airway Management; D016887:Cardiopulmonary Resuscitation; D005260:Female; D005858:Germany; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods*; D008297:Male; D058687:Out-of-Hospital Cardiac Arrest / Q000628:therapy*; D010043:Outcome and Process Assessment, Health Care; D012042:Registries; D012307:Risk Factors; D017211:Treatment Failure