title: Failure of the Laryngeal Mask Airway Unique™ and Classic™ in the pediatric surgical patient: a study of clinical predictors and outcomes.
abstract: BACKGROUND
  Although predictors of laryngeal mask airway failure in adults have been elucidated, there remains a paucity of data regarding laryngeal mask airway failure in children.
  
  
  METHODS
  The authors performed a retrospective database review of all pediatric patients who received a laryngeal mask anesthetic at their institution from 2006 to 2010. Device brands were restricted to LMA Unique™ (Cardinal Health, Dublin, OH) and LMA Classic™ (LMA North America, San Diego, CA), and primary outcome was laryngeal mask failure, defined as any airway event requiring device removal and tracheal intubation. Potential risk factors were analyzed with both univariate and multivariate techniques and included medical history, physical examination, surgical, and anesthetic characteristics.
  
  
  RESULTS
  Of the 11,910 anesthesia cases performed in the study, 102 cases (0.86%) experienced laryngeal mask failure. Common presenting features of laryngeal mask failures included leak (25%), obstruction (48%), and patient intolerance such as intractable coughing/bucking (11%). Failures occurred before incision in 57% of cases and after incision in 43%. Independent clinical associations included ear/nose/throat surgical procedure, nonoutpatient admission status, prolonged surgical duration, congenital/acquired airway abnormality, and patient transport.
  
  
  CONCLUSIONS
  The findings of the study support the use of the LMA Unique™ and LMA Classic™ as reliable pediatric supraglottic airway devices, demonstrating relatively low failure rates. Predictors of laryngeal mask airway failure in the pediatric surgical population do not overlap with those in the adult population and should therefore be independently considered.
authors.affiliation: * Anesthesiology Resident, † Assistant Professor, ‡ Consultant Anesthetist, § Research Associate, ‖ Professor, Department of Anesthesiology, University of Michigan Medical School, Michigan, Ann Arbor.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Mathis
authors.forename: Bishr
authors.initials: B
authors.lastname: Haydar
authors.forename: Emma L
authors.initials: EL
authors.lastname: Taylor
authors.forename: Michelle
authors.initials: M
authors.lastname: Morris
authors.forename: Shobha V
authors.initials: SV
authors.lastname: Malviya
authors.forename: Robert E
authors.initials: RE
authors.lastname: Christensen
authors.forename: Satya-Krishna
authors.initials: SK
authors.lastname: Ramachandran
authors.forename: Sachin
authors.initials: S
authors.lastname: Kheterpal
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000402:Airway Obstruction / Q000453:epidemiology / Q000209:etiology; D000758:Anesthesia; D002648:Child; D002675:Child, Preschool; D003627:Data Interpretation, Statistical; D016208:Databases, Factual; D004868:Equipment Failure; D005260:Female; D005544:Forecasting; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D017214:Laryngeal Masks / Q000009:adverse effects*; D008297:Male; D015999:Multivariate Analysis; D059035:Perioperative Period; D012140:Respiratory Tract Diseases / Q000151:congenital; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome