STOP-BANG questionnaire as predictor of a difficult airway management during anesthesia

Abstract

Obstructive sleep apnea (OSA) is highly prevalent. The STOP-BANG questionnaire is a simple and useful tool to screen for OSA. Since OSA is strongly associated with airway management troubles, we sought to determine whether the STOP-BANG can predict difficult airway management. An observational, cross-sectional study was conducted including adult patients scheduled for major outpatient surgery under general anesthesia. The STOP-BANG questionnaire was preoperatively applied by a ward nurse. The Han scale mask ventilation difficulty scale, Cormack-Lehane laryngeal view scale were also applied and the need for video laryngoscopy was recorded. The number of attempts for successful insertion of a laryngeal mask airway were determined. We studied 993 patients, of whom 53% required tracheal intubation and 47% a laryngeal mask. Most patients had a low OSA risk, (STOP-BANG < 3). STOP-BANG score was associated with difficult airway management (p < 0.05), except for the laryngeal mask airway insertion. The effect size was especially high for difficult mask ventilation with an Odds Ratio of 1.7 [ 95% confidence intervals (CI)1.2 - 2.4] and for video laryngoscopy, with an Odds Ratio of 1.6 [95% CI: 1.6 - 2.1]. The area under the receiver operating characteristic (ROC) curve was above 0.7, (acceptable level), only for predicting difficult mask ventilation. The cut-off for having a difficult mask ventilation was a STOP-BANG > 2. The positive and negative likelihood ratios, (2.0 and 0.2) imply poor predictive capability. The STOP-BANG questionnaire was only able to predict difficult mask ventilation. Since its discriminative value was low, it cannot be recommended it as a single predictor.