Airway physical examination tests for detection of difficult airway management in apparently normal adult patients

• Published in: Cochrane database of systematic reviews 2018-05, Vol.5 (5), p.CD008874-CD008874
• Main Authors: Roth, Dominik, Pace, Nathan L, Lee, Anna, Hovhannisyan, Karen, Warenits, Alexandra-Maria, Arrich, Jasmin, Herkner, Harald
• Format: Article
• Language: English
• Subjects: Adult; Airway management; Airway Management - statistics & numerical data; Diagnosis; Humans; Intubation, Intratracheal - statistics & numerical data; Laryngoscopy - statistics & numerical data; Lungs & airways; Pain & anaesthesia; Physical Examination - methods; Point-of-Care Systems - statistics & numerical data; Sensitivity and Specificity; Treatment Failure
• ISSN: 1469-493X
• DOI: 10.1002/14651858.CD008874.pub2

The unanticipated difficult airway is a potentially life-threatening event during anaesthesia or acute conditions. An unsuccessfully managed upper airway is associated with serious morbidity and mortality. Several bedside screening tests are used in clinical practice to identify those at high risk of difficult airway. Their accuracy and benefit however, remains unclear. The objective of this review was to characterize and compare the diagnostic accuracy of the Mallampati classification and other commonly used airway examination tests for assessing the physical status of the airway in adult patients with no apparent anatomical airway abnormalities. We performed this individually for each of the four descriptors of the difficult airway: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation. We searched major electronic databases including CENTRAL, MEDLINE, Embase, ISI Web of Science, CINAHL, as well as regional, subject specific, and dissertation and theses databases from inception to 16 December 2016, without language restrictions. In addition, we searched the Science Citation Index and checked the references of all the relevant studies. We also handsearched selected journals, conference proceedings, and relevant guidelines. We updated this search in March 2018, but we have not yet incorporated these results. We considered full-text diagnostic test accuracy studies of any individual index test, or a combination of tests, against a reference standard. Participants were adults without obvious airway abnormalities, who were having laryngoscopy performed with a standard laryngoscope and the trachea intubated with a standard tracheal tube. Index tests included the Mallampati test, modified Mallampati test, Wilson risk score, thyromental distance, sternomental distance, mouth opening test, upper lip bite test, or any combination of these. The target condition was difficult airway, with one of the following reference standards: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation. We performed screening and selection of the studies, data extraction and assessment of methodological quality (using QUADAS-2) independently and in duplicate. We designed a Microsoft Access database for data collection and used Review Manager 5 and R for data analysis. For each index test and each reference standard, we assessed sensitivity and specificity. We produced forest