A Study to Predict Difficult Intubation Using Simple Non-invasive test: A Prospective Observational Study

  • Asha Attar Asst. Prof., Vedantaa Institute of Medical Sciences, Palghar.
  • Ravindra Gandhi Associate Prof., Vedantaa Institute of Medical Sciences, Palghar.
Keywords: Airway Management, ULBT, HMD, TSD, TMD, ML & Cormack Lehane grading.


Background: Airway Management is prime importance to the anaesthesiologist of all the anaesthetic deaths 30 % to 40 % are attributed to the inability to manage a difficult airway. The various simple bedside predictors of difficult airway like Mallampati test, Upper lip bite test, Thyromental, Hyomental, Thyrosternal & Sternomental distances, mandibular length, Neck circumferences etc. are easy to perform with No extra cost or inconvenience to patients. Aim: To assess the predictability of Upper lip bite test, Hyomental distance, Thyromental distance, Thyrosternal distance & Mandibular length. Objective: 1) To find out the best predictor of difficult intubation amongst the Upper Lip Bite Test, Hyomental Distance, Thyromental Distance, Thyrosternal Distance & Mandibular Length on the basis of the test. Methods: This is a prospective observational study of 110 patients are randomly selected & age caring between 20 to 59 yrs both male and female are presented in anaesthesia of routine per anaesthetic check-up. After from mouth opening & mallampati test which are routinely done airway assessment included ULBT, HMD, TMD, TSD & ML will be done.

Results: After analysing study state that the age (P = 0.031) were significant , & sex (P = 0.213) ASA (P = 0.091) were not significant with difficult intubation on the basis of Cormack lehane grading. All these factors were applicant on next set of 110 patients to found sensitivity & specificity to be ULBT ( SE = 50.00%, SP =100.00%), HMD (SE = 10.00%, SP = 97.00%), TSD (SE = 0.00%, SP = 97.00%), ML (SE = 20.00%, SP = 97.00%) & TMD (SE = 70.00%, SP = 85.00%) respectively.

Conclusions: Thyromental distance is the most important sensitive factors predicting difficult intubation on the basis of cormack lehane grading in indian patients.


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How to Cite
Attar A, Gandhi R. A Study to Predict Difficult Intubation Using Simple Non-invasive test: A Prospective Observational Study . Int Arch BioMed Clin Res [Internet]. 2019Sep.30 [cited 2022Aug.12];5(3):27-1. Available from: https://www.iabcr.org/index.php/iabcr/article/view/493
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