title: Risk factors for unsuccessful prehospital laryngeal tube placement.
abstract: BACKGROUND
  Laryngeal tube (LT) airways are commonly used in the prehospital setting, but there are limited data on clinical success rates across emergency medical services (EMS) agencies. We aimed to determine factors associated with unsuccessful LT placement in the prehospital setting.
  
  
  METHODS
  We retrospectively reviewed all King LT placement attempts by prehospital providers in 35 ground advanced life support EMS agencies and one air medical critical care service with 17 rotorwing bases, between January 1, 2006 and August 31, 2011. Success of King LT placement and patient, procedural, and agency factors present were identified using descriptive statistics. Factors associated with unsuccessful laryngeal tube placement were identified using multivariable logistic regression.
  
  
  RESULTS
  During the study period, we observed 511 attempts at laryngeal tube placement by paramedics or prehospital nurses in 477 patients. Unsuccessful LT placement occurred in 15.1% of first attempts and 9.9% of cases overall. The majority (79.2%) of first attempts occurred as a rescue airway after unsuccessful endotracheal intubation attempt(s), in patients with non-traumatic complaints (70.9%) and in cardiac arrest (60.8%). Gag reflex (OR 4.08, 95% CI 1.72-9.67), ground (versus air) EMS agency (OR 2.49, 95% CI 1.07-5.79), and male gender (OR 1.90, 95% CI 1.04-3.46) were associated with unsuccessful LT placement in our multivariable model.
  
  
  CONCLUSIONS
  The laryngeal tube is an effective airway management tool for both advanced life support and critical care prehospital providers. Gag reflex, ground (versus air) EMS agency, and male gender were associated with unsuccessful laryngeal tube placement by prehospital personnel.
authors.affiliation: Department of Emergency Medicine, University of Pittsburgh, Iroquois Building, Suite 400A, 3600 Forbes Avenue, Pittsburgh, PA 15261, United States. Electronic address: martingillc2@upmc.edu.
authors.forename: Christian
authors.initials: C
authors.lastname: Martin-Gill
authors.affiliation: Department of Emergency Medicine, University of Pittsburgh, Iroquois Building, Suite 400A, 3600 Forbes Avenue, Pittsburgh, PA 15261, United States.
authors.forename: Heather A
authors.initials: HA
authors.lastname: Prunty
authors.affiliation: Department of Emergency Medicine, University of Pittsburgh, Iroquois Building, Suite 400A, 3600 Forbes Avenue, Pittsburgh, PA 15261, United States.
authors.forename: Seth C
authors.initials: SC
authors.lastname: Ritter
authors.affiliation: St. Vincent's Medical Center, Department of Emergency Medicine, Allegheny Health Network, 232 West 25th Street, Erie, PA 16544, United States.
authors.forename: Jestin N
authors.initials: JN
authors.lastname: Carlson
authors.affiliation: Department of Emergency Medicine, University of Pittsburgh, Iroquois Building, Suite 400A, 3600 Forbes Avenue, Pittsburgh, PA 15261, United States.
authors.forename: Francis X
authors.initials: FX
authors.lastname: Guyette
mesh_terms: D004632:Emergency Medical Services; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal; D007830:Larynx; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D017211:Treatment Failure
keywords: Airway management; Emergency medical services; Procedure failure; Supraglottic airway