Difficult airway predictors for anticipated or unanticipated difficult airway in patients with fibreoptic intubation: a retrospective observational study

Airway management is a cornerstone of anaesthesia. The aim of the study was to identify difficult airway (DA) predictors for patients with fibreoptic intubation (FOI). This retrospective cohort study included 135 adult patients undergoing general anaesthesia with the use of FOI at Rīga East University Hospital from 1 January 2018 to 31 December 2022. For analysis, 135 patients were divided into two groups according to unanticipated (un-DA, n = 33) or anticipated DA: (a-DA, n = 102). Data were analysed using SPSS 26.0, p < 0.05. FOI was used only in 135 cases of 50,186 general anaesthesia cases over the study period. Of 135 FOI cases, 75 (55.6%) were males with a median age of 62 ± 19 years; 24.4% FOI was used in acute and 75.6% in elective surgeries. Those with a-DA had a higher Mallampati score, on average 3.2 vs. 2.1, p = 0.002. Unanticipated DA were reported statistically more frequently in acute admission cases compared to elective surgeries — 39.3% vs 10.8% of cases. Previously known tracheal pathologies such as dislocation (p = 0.001) and stenosis (p = 0.011) were statistically reliable factors for the anticipated DA. Comparing a-DA and un-DA groups for combinations of predictors (Mallampati score, admission and tracheal pathology) we found a sensitivity and specificity 70.3% and 68.7% to predict DA. Mallampati score, acute admission, and previously known tracheal pathology are reliable predictors of DA in patients undergoing FOI. Acute admission had the greatest impact on unanticipated DA.