A Pilot Study of Preoperative Submandibular POCUS to Predict Difficult Mask Ventilation

Area of Science:

• Anesthesiology
• Ultrasound Imaging
• Sleep Medicine

Background:

• Difficult mask ventilation poses risks during anesthesia.
• Obstructive sleep apnea (OSA) is a known risk factor for challenging mask ventilation.
• Existing assessment tools may be supplemented by objective measurements.

Purpose of the Study:

• To investigate the correlation between submandibular point-of-care ultrasound (POCUS) findings and difficult mask ventilation.
• To assess if POCUS can identify patients at higher risk for mask ventilation difficulties, particularly those with OSA.

Main Methods:

• An observational study involving patients screened with the STOP-BANG questionnaire for OSA risk.
• Submandibular POCUS was performed to measure several anatomical parameters: tongue thickness (TT), geniohyoid muscle thickness (GMT), distance between lingual arteries (DLA), lateral pharyngeal wall thickness (LPW), hyomental distance (HMD), and oral cavity height (OCH).
• Correlation analysis was performed between POCUS measurements and difficult mask ventilation scores.

Main Results:

• Patients with higher STOP-BANG scores (≥3) exhibited larger TT, GMT, DLA, and HMD.
• Increased TT and DLA were significantly associated with the need for airway adjuncts or assistance from multiple practitioners during mask ventilation.
• Both increased TT (OR 1.152) and DLA (OR 1.207) were independently associated with higher mask ventilation difficulty scores.

Conclusions:

• Submandibular POCUS measurements, particularly TT and DLA, show potential as objective markers for predicting difficult mask ventilation.
• This technique may aid in identifying high-risk patients, especially those with suspected OSA based on STOP-BANG scores.
• POCUS offers a non-invasive method to enhance pre-anesthetic assessment for mask ventilation challenges.