STOP-Bang and prediction of difficult airway in obese patients.

Study Objective: To determine if a high score (≥ 3) on the STOP-Bang screening questionnaire for obstructive sleep apnea (OSA) predicts whether obese patients are at high risk for OSA and increased risk of difficult airway.

Design: Prospective, questionnaire-based clinical assessment.

Setting: University-affiliated hospital.

Patients: 127 ASA physical status 2 and 3 patients, who were scheduled for elective bariatric surgery.

Interventions: Patients were allocated to three groups. Group 1 patients had a previous history of OSA, Group 2 patients had no history of OSA but did have a high STOP-Bang score (≥ 3), and Group 3 patients had no history of OSA but did have a low STOP-Bang score (< 3). Groups 2 and 3 only were assessed using the STOP-Bang questionnaire. After induction and intubation of the patient, an anesthesiologist who was blinded to the three study group allocations completed an airway questionnaire on the three study groups.

Measurements: The frequency of difficult airway, difficult mask ventilation with or without muscle relaxation, poor visualization of the vocal cords, difficulty in blade insertion, and difficult intubation were compared.

Main Results: The group of patients with high STOP-Bang scores (Group 2) and those patients previously diagnosed with OSA (Group1) showed a higher risk for difficult airway than the patients with low STOP-Bang scores (Group 3; P < 0.001).

Conclusion: The STOP-Bang score may be used as an effective predictor of difficult airway in obese patients. Obese surgical patients with unknown/undiagnosed OSA status should be evaluated using the STOP-Bang questionnaire score.