Acta Medica Iranica 2017. 55(7):453-458.

Predicting Difficult Laryngoscopy and Intubation With Laryngoscopic Exam Test: A New Method
Mahmood Akhlaghi, Mohammadreza Abedinzadeh, Ali Ahmadi, Zohre Heidari


Airway assessment is fundamental skill for anesthesiologists and failure to maintain a patient’s airway is the tremendous cause of anesthesia-related morbidity and mortality. None of the tests which have recommended for predicting difficult intubation stands out to be the best clinical test or have high diagnostic accuracy. Our study aimed to determine the utility of a new test as “laryngoscopic exam test (LET)” in predicting difficult intubation. Three hundred and eleven patients aged 16-60 years participated and completed the study. Airway assessment was carried out with modified Mallampati test, upper lip bit test and LET preoperatively, and Cormack and Lehane's grading of laryngoscopy were assessed during intubation as a gold standard, and difficult laryngoscopy was considered as Cormack and Lehane's grade ΙΙΙ or ΙV of laryngoscopic view. The incidence of difficult intubation was 6.1%. The LET showed higher sensitivity, specificity, and accuracy (P<0.05), without revealing significant differences among three tests (P=0.375). The LET is a simple bedside test and an alternative method for predicting difficult intubation.


Difficult intubation; Airway management; Laryngoscopy; Mallampati

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