title: Determination of the diagnostic value of the Modified Mallampati Score, Upper Lip Bite Test and Facial Angle in predicting difficult intubation: A prospective descriptive study.
abstract: BACKGROUND
  Difficult intubation is a significant cause of mortality and morbidity related to anesthesia. We decided to evaluate the value of Modified Mallampati Score, Upper Lip Bite Test and Facial Angle in the prediction of difficult intubation.
  
  
  METHODS
  In a prospective descriptive study, data from 132 patients who were candidates for elective maxillofacial surgeries under general anesthesia were gathered. Facial Angles were measured by a maxillofacial surgeon according to cephalometry. The Modified Mallampati Score and Upper Lip Bite Test were first measured by an anesthesiologist and then another anesthesiologist was assigned to record the Cormack and Lehane score during the intubation. Grades 3 and 4 were considered as difficult intubation. Sensitivity, specificity, positive predictive value, negative predictive value and Youden index were calculated for all tests.
  
  
  RESULTS
  Difficult intubation was reported in 12% of the patients. Facial Angle≤82.5° can predict difficult intubation with 87.5% sensitivity and 88.8% specificity. Among the three tests, a high Modified Mallampati Score had the highest specificity (94.5%) and a high Modified Mallampati Score and Facial Angle (FA≤82.5°) had the highest sensitivity (87.5%). The highest NPV, sensitivity and Youden index were observed when using Facial Angle with the Modified Mallampati Score or with Upper Lip Bite Test.
  
  
  CONCLUSIONS
  Facial Angle has a high sensitivity, NPV and Youden index for the prediction of difficult intubation, but the best result is achieved when Facial Angle is used in combination with either the Modified Mallampati Score or Upper Lip Bit Test.
authors.affiliation: Anesthesiology Research Team, Department of Anesthesiology, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Ata
authors.initials: A
authors.lastname: Mahmoodpoor
authors.affiliation: Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.. Electronic address: soleimanpourh@tbzmed.ac.ir.
authors.forename: Hassan
authors.initials: H
authors.lastname: Soleimanpour
authors.affiliation: Medical Philosophy and History Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Samad Ej
authors.initials: SE
authors.lastname: Golzari
authors.affiliation: Students' Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Arezoo
authors.initials: A
authors.lastname: Nejabatian
authors.affiliation: Department of Oral & Maxillofacial Surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Tannaz
authors.initials: T
authors.lastname: Pourlak
authors.affiliation: Department of Oral & Maxillofacial Surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Amani
authors.affiliation: Department of Oral & Maxillofacial Surgery, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Hajmohammadi
authors.affiliation: Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Hamzeh
authors.initials: H
authors.lastname: Hosseinzadeh
authors.affiliation: Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz 51664, Iran.
authors.forename: Robab Mehdizadeh
authors.initials: RM
authors.lastname: Esfanjani
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000768:Anesthesia, General / Q000009:adverse effects*; D017558:Elective Surgical Procedures / Q000009:adverse effects*; D005145:Face / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D005544:Forecasting / Q000379:methods; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects*; D019647:Oral Surgical Procedures / Q000009:adverse effects*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011859:Radiography; D013997:Time Factors; D055815:Young Adult
keywords: Difficult intubation; Facial Angle; Modified Mallampati Score; Upper Lip Bite Test