title: A comparison of the upper lip bite test (a simple new technique) with modified Mallampati classification in predicting difficulty in endotracheal intubation: a prospective blinded study.
abstract: We explored the possibility that a simple and single test could replace the modified Mallampati score for either a difficult or an unaccomplished tracheal intubation in an impending hypoxic patient. Three hundred adult patients were enrolled in this study. They were subjected to the following assessments: 1) oropharyngeal class according to the modified Mallampati criteria; 2) the new, upper lip bite criteria-class I = lower incisors can bite the upper lip above the vermilion line, class II = lower incisors can bite the upper lip below the vermilion line, and class III = lower incisors cannot bite the upper lip; and 3) laryngeal view grading according to Cormack's criteria. The incidence of difficult intubation was 5.7%. The upper lip bite test showed significantly higher specificity and accuracy than the modified Mallampati test (P < 0.001). Comparisons of sensitivity, positive and negative predictive values, between the two tests, however, did not reveal any significant differences (P > 0.05). In conclusion, the upper lip bite test is an acceptable option for predicting difficult intubation as a simple, single test.
authors.affiliation: Department of Anesthesiology, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran. arash_kashfi@hotmail.com
authors.forename: Zahid Hussain
authors.initials: ZH
authors.lastname: Khan
authors.forename: Arash
authors.initials: A
authors.lastname: Kashfi
authors.forename: Elham
authors.initials: E
authors.lastname: Ebrahimkhani
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000768:Anesthesia, General; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal; D007574:Jaw Relation Record / Q000379:methods*; D007828:Laryngoscopy; D008046:Lip / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D014070:Tooth / Q000033:anatomy & histology