Evaluation of anthropometric measurements and clinical tests in the diagnosis of difficult airway in patients undergoing head and neck surgery.

Background: The aim of this study is to research the incidence of difficult airways and the effectiveness of anthropometric measurements and clinical tests used to predict difficult airways in patients undergoing head and neck surgery.

Methods: This study was performed on a total of 200 patients over the age of 18 who underwent head and neck surgery between December 2019 and March 2020. The demographic data of the patients in the preoperative period, previous operations/ radiotherapy history applied to the head and neck region, and obstructive sleep apnea syndrome symptoms were recorded. In the physical examination, the jaw structure, mouth opening, jaw movement, and tooth structure of the patients, modified Mallampati classification, head and neck movements, neck circumference, thyromental and sternomental distance, atlantooccipital joint mobility, upper lip bite test, Wilson risk scoring, and Cormack-Lehane classification were evaluated.

Results: The difficult laryngoscopy rate was identified as 19%, and the difficult intubation rate as 8%. Operation history related to head and neck (p = 0.002), presence of at least two of the obstructive sleep apnea syndrome symptoms (p = 0.008), Modified Mallampati score (p = 0.009), Wilson risk score (p = 0.004), upper lip bite test (p < 0.0001) and mouth opening (p = 0.001) were found to be associated with difficult laryngoscopy. Modified Mallampati score (p = 0.002), Wilson risk score (p < 0.0001), upper lip bite test (p < 0.0001), mouth opening (p < 0.0001), sternomental distance (p = 0.003), Atlantooccipital joint mobility (p = 0.001), and Cormack-Lehane classification (p < 0.0001) were found to be associated with difficult intubation. According to multiple logistic regression analysis, the results obtained for sternomental distance and mouth opening were OR 0.8, 95% CI 0.6-1.1 and OR 0.2, 95% CI 0.1-0.4, respectively.

Discussion: In patients who underwent head and neck surgery, it was observed that the frequency of difficult airway was higher, and particularly the Modified Mallampati score, Wilson risk score, upper lip bite test, and mouth opening were associated with both difficult laryngoscopy and difficult intubation.