title: Evaluation of laryngoscopic views and related influencing factors in a pediatric population.
abstract: BACKGROUND
  Management of the difficult pediatric airway is a serious problem that anesthesiologists face in their practice. However, guidelines for adults may not be applied readily to pediatric populations.
  
  
  OBJECTIVE
  This study was performed to determine the incidence of different laryngoscopic views and the associated conditions.
  
  
  METHODS
  The authors collected data on 511 consecutive patients who were scheduled to receive general anesthesia. Laryngeal views were graded using the Cormack and Lehane classification, and grades III and IV were defined as difficult laryngoscopic visualization. The distances from the nose to the upper lip, lower lip to menthom, ear tragus to mouth, ear lobe to mouth, the horizontal length of mandible, and thyromental distance were measured. The association of these parameters with the laryngoscopic views was analyzed.
  
  
  RESULTS
  The incidence of grade I to IV laryngoscopic views was 80%, 17%, 3%, and 0%, respectively. All the cases that involved difficult laryngoscopy (3%) were aged ≤3 months. The distances from the lower lip to menthom and ear tragus to mouth had a direct association with difficult cases. There were no apparent cutoff points to predict difficult laryngoscopy, for any of the distances.
  
  
  CONCLUSIONS
  The difficult cases were mostly aged <1 year. The association between difficult laryngoscopy and the distances between the lower lip border and menthom, ear tragus and corner of the mouth, and ear lobe and corner of the mouth can be summarized in an equation that may have potential use in the prediction of difficult laryngoscopy.
authors.affiliation: Department of Anesthesiology, Children Medical Center, Tehran University of Medical Sciences, Tehran, Iran. a_mirghasemi@yahoo.com
authors.forename: Asadollah
authors.initials: A
authors.lastname: Mirghassemi
authors.forename: Alireza E
authors.initials: AE
authors.lastname: Soltani
authors.forename: Maryam
authors.initials: M
authors.lastname: Abtahi
mesh_terms: D000293:Adolescent; D058109:Airway Management / Q000379:methods; D000768:Anesthesia, General; D000769:Anesthesia, Inhalation; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004431:Ear, External / Q000033:anatomy & histology; D005260:Female; D006257:Head / Q000033:anatomy & histology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007828:Laryngoscopy / Q000379:methods*; D008046:Lip / Q000033:anatomy & histology; D008297:Male; D009055:Mouth / Q000033:anatomy & histology; D009296:Nasal Cavity / Q000033:anatomy & histology; D012372:ROC Curve; D012044:Regression Analysis