Brazilian Journal of Anesthesiology
Brazilian Journal of Anesthesiology
Systematic Review

Predictive performance of thyromental height for difficult laryngoscopies in adults: a systematic review and meta-analysis

Clístenes Crístian de Carvalho, Jayme Marques Santos Neto, Flávia Augusta de Orange

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Thyromental height (TMH) was first reported as a great single test for prediction of difficult laryngoscopies, although further studies have shown variable estimates of its accuracy. We thus performed this meta-analysis to summarize the predictive values of TMH mainly for prediction of difficult laryngoscopies.

A search in PubMed, EMBASE, LILACS, and Scielo was conducted in June 2020. We included prospective cohorts fully reported with patients ≥ 16 years old, providing data on predictive values of TMH for prediction of either difficult laryngoscopies or difficult intubations. Diagnostic properties and association between TMH and Cormack and Lehanes’s classification by direct laryngoscopy were evaluated. A random-effects meta-analysis using hierarchical models was performed.

Eight studies evaluating 2844 patients were included. All included studies had high risk of bias and low concern regarding applicability. There was significant heterogeneity among the studies. The pooled diagnostic odds ratio (DOR) and positive (LR+) and negative (LR-) likelihood ratios were as follows: DOR, 57.94 (95% CI: 18.19–184.55); LR+, 11.32 (95% CI: 4.28–29.92); and LR-, 0.23 (95% CI: 0.15–0.35). Summary sensitivity and specificity for studies with common threshold were 82.6 (95% CI: 74–88.8%) and 93.5 (95% CI: 79–98.2%), respectively. The estimated AUC was 81.1%.

TMH arises as a good predictor of difficult laryngoscopies in adult patients from diverse populations presenting better predictive values than most previously reported bedside tests. However, the high risk of bias throughout the studies may have skewed the results of the individual research as well as the summary points of the present meta-analysis.


Airway management;  Laryngoscopy;  Intubation, intratracheal;  Systematic review;  Meta-analysis;  Sensitivity and specificity


1 T.M. Cook, N. Woodall, C. Frerk Major complications of airway management in the UK: Results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: Anaesthesia Br J Anaesth., 106 (2011), pp. 617-631

2 C. Frerk, V.S. Mitchell, A.F. McNarry, et al. Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults Br J Anaesth., 115 (2015), pp. 827-848

3 A. Higgs, B.A. McGrath, C. Goddard, et al. Guidelines for the management of tracheal intubation in critically ill adults Br J Anaesth., 120 (2018), pp. 323-352

4 D. Roth, N.L. Pace, A. Lee, et al. Bedside tests for predicting difficult airways: an abridged Cochrane diagnostic test accuracy systematic review Anaesthesia., 74 (2019), pp. 915-928

5 M.E. Detsky, N. Jivraj, N.K. Adhikari, et al. Will this patient be difficult to intubate? the rational clinical examination systematic review JAMA., 321 (2019), pp. 493-503

6 A.K. Nørskov, C.V. Rosenstock, J. Wetterslev, et al. Diagnostic accuracy of anaesthesiologists’ prediction of difficult airway management in daily clinical practice: a cohort study of 188 064 patients registered in the Danish Anaesthesia Database Anaesthesia., 70 (2015), pp. 272-281

7 J.L. Apfelbaum, C.A. Hagberg, R.A. Caplan, et al. Practice Guidelines for Management of the Difficult Airway: An Updated Report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway Anesthesiology., 118 (2013), pp. 251-270

8 T.M. Cook, N. Woodall, J. Harper, et al. Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 2: intensive care and emergency departments Br J Anaesth., 106 (2011), pp. 632-642

9 J.A. Law, N. Broemling, R.M. Cooper, et al. The difficult airway with recommendations for management - Part 2 - Difficult airway Can J Anesth., 60 (2013), pp. 1119-1138

10 J.J. Pandit, T. Heidegger Putting the “point” back into the ritual: a binary approach to difficult airway prediction Anaesthesia., 72 (2017), pp. 283-288

11 A. Vannucci, L.F. Cavallone Bedside predictors of difficult intubation : a systematic review Minerva Anestesiol., 82 (2016), pp. 69-83

12 O. Hung, J.A. Law, I. Morris, et al. Airway assessment before intervention: What we know and what we do Anesth Analg., 122 (2016), pp. 1752-1754

13 F. Etezadi, A. Ahangari, H. Shokri, et al. Thyromental height: A new clinical test for prediction of difficult laryngoscopy Anesth Analg., 117 (2013), pp. 1347-1351

14 O. Selvi, T. Kahraman, O. Senturk, et al. Evaluation of the reliability of preoperative descriptive airway assessment tests in prediction of the Cormack-Lehane score: A prospective randomized clinical study J Clin Anesth., 36 (2017), pp. 21-26

15 N. Jain, S. Das, M. Kanchi Thyromental height test for prediction of difficult laryngoscopy in patients undergoing coronary artery bypass graft surgical procedure Ann Card Anaesth., 20 (2017), pp. 207-211

16 M. Nurullah, M.S. Alam, M. Hossen, et al. Prediction of difficult airway by thyromental height test-a comparison with modified mallampati test Bangladesh J Med Sci., 17 (2018), pp. 455-461

17 K.V.N. Rao, D. Dhatchinamoorthi, A. Nandhakumar, et al. Validity of thyromental height test as a predictor of difficult laryngoscopy: A prospective evaluation comparing modified Mallampati score, interincisor gap, thyromental distance, neck circumference, and neck extension Indian J Anaesth., 62 (2018), pp. 603-608

18 S. Yabuki, S. Iwaoka, M. Murakami, et al. Reliability of the thyromental height test for prediction of difficult visualisation of the larynx: A prospective external validation Indian J Anaesth., 63 (2019), pp. 270-276

19 P. Panjiar, A. Kochhar, K. Bhat, et al. Comparison of thyromental height test with ratio of height to thyromental distance, thyromental distance, and modified Mallampati test in predicting difficult laryngoscopy: A prospective study J Anaesthesiol Clin Pharmacol., 35 (2019), pp. 390-395

20 M. Mostafa, M. Saeed, A. Hasanin, et al. Accuracy of thyromental height test for predicting difficult intubation in elderly J Anesth., 34 (2020), pp. 217-223

21 P. Macaskill, C. Gatsonis, J.J. Deeks, et al. Analysing and presenting results J.J. Deeks, P.M. Bossuyt, C. Gatsonis (Eds.), Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy Version 1.0, The Cochrane Collaboration (2010) Available at: (Accessed April 1, 2020)

22 K.W. Kim, J. Lee, S.H. Choi, et al. Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers–part I. General guidance and tips Korean J Radiol., 16 (2015), pp. 1175-1187

23 J. Lee, K.W. Kim, S.H. Choi, et al. Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers–part II. Statistical methods of meta-analysis Korean J Radiol., 16 (2015), pp. 1188-1196

24 W.M. Bramer, G.B. de Jonge, M.L. Rethlefsen, et al. A systematic approach to searching: An efficient and complete method to develop literature searches J Med Libr Assoc., 106 (2018), pp. 531-541

25 D. Moher, L. Shamseer, M. Clarke, et al. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement Syst Rev., 4 (2015), p. 1

26 D. Moher, A. Liberati, J. Tetzlaff, et al. Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement PLoS Med., 6 (2009), Article e1000097

27 T.A. McGrath, M. Alabousi, B. Skidmore, et al. Recommendations for reporting of systematic reviews and meta-analyses of diagnostic test accuracy: A systematic review Syst Rev., 6 (2017), p. 194

28 M.D.F. Mclnnes, D. Moher, B.D. Thombs, et al. Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies: The PRISMA-DTA Statement JAMA., 319 (2018), pp. 388-396

29 P.F. Whiting, A.W.S. Rutjes, M.E. Westwood, et al. Quadas-2: A revised tool for the quality assessment of diagnostic accuracy studies Ann Intern Med., 155 (2011), pp. 529-536

30 Review Manager (RevMan) [Computer program] Version 5.3. Copenhagen, Denmark: The Nordic Cochrane Centre, The Cochrane Collaboration (2014)

31 R CoreTeam R: A Language and Environment for Statistical Computing R Foundation for Statistical Computing, Vienna, Austria (2013)

32 S.R. Shim, S.-J. Kim, J. Lee Diagnostic test accuracy: application and practice using R software Epidemiol Health., 41 (2019), Article e2019007

33 P. Palczynski, S. Bialka, H. Misiolek, et al. Thyromental height test as a new method for prediction of difficult intubation with double lumen tube PLoS One., 13 (2018), pp. 1-13

34 T. Shiga, Z. Wajima, T. Inoue, et al. Predicting difficult intubation in apparently normal patients: a meta-analysis of bedside screening test performance Anesthesiology., 103 (2005), pp. 429-437

35 A.K. Nørskov Pre-operative Airway Assessment – Experience Gained from a Multicentre Cluster Randomised Trial and the Danish Anaesthesia Database. [PhD thesis] University of Copenhagen, Copenhagen, Denmark (2015)

36 J.E. Fischer, L.M. Bachmann, R. Jaeschke A reader’s guide to the interpretation of diagnostic test properties: clinical examples of sepsis Intensive Care Med., 29 (2003), pp. 1043-1051

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