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Updated: Feb 5, 2026
A Novel Rescue Technique for Difficult Intubation and Difficult Ventilation
Published on: January 17, 2011
Thyromental height test as a new method for prediction of difficult intubation with double lumen tube
Piotr Palczynski1, Szymon Bialka1, Hanna Misiolek1
1Department of Anaesthesiology and Intensive Care, Medical University of Silesia, Katowice, Poland.
Background:
Predicting difficult intubation is of high clinical interest.
Methods:
237 patients aged ≥18 years were included in the study. Preoperative airway evaluation included: Mallampati test, thyromental distance, sternomental distance and thyromental height test. During direct laryngoscopy Cormack & Lehane classification was graded. We calculated the ROC AUC, sensitivity and specificity for thyromental height test as a primary end point of our study.
Results:
Only thyromental height test and Cormack-Lehane scale proved significant on occurrence of difficult intubation. The optimal sensitivity and specificity values of thyromental height test were met with a cut off value of 50 mm. With 1 mm increase in thyromental height test, risk of difficult intubation decreased by 7%.
Conclusion:
Thyromental height test is a simple, easy to perform and non-invasive test to predict difficult intubation in patients scheduled for elective double lumen tube intubation during thoracic surgical procedures. With 1 mm above 50 mm increase in thyromental height test the risk of difficult intubation decreased by 7%.
Trial Registration:
Clinicaltrials.gov Identifier: NCT02988336.
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