Airway Ultrasound as a Method of Airway Assessment: Review Article

Background: Unanticipated and challenging endotracheal intubation continues to pose a significant clinical challenge, particularly when accompanied by difficulty in ventilation. It is linked to serious complications, including airway trauma, laryngospasm, hypoxemia, and cardiac arrhythmias. Despite the availability of various clinical screening tools, a subset of patients initially assessed as having an uncomplicated airway may still experience unforeseen difficulties. Ultrasound (US) imaging is a simple, portable, non-invasive tool that can aid in rapid assessment of airway anatomy not only in the operating theatre but also in the intensive care unit and emergency department. Objective: This review aimed to evaluate the value of airway US in the assessment and prediction of difficult intubation in adult patients undergoing general anaesthesia. Conclusions: Although no single US measurement has been universally accepted, several indices, such as increased tongue thickness (> 6.1 mm), skin-to-epiglottic distance (> 2.54 cm), and pre-epiglottic area (> 5.04 cm), demonstrated high sensitivity and specificity for predicting difficult airways. US also assisted in evaluating tracheal size, identifying pathological changes (e.g., tumors or goitres), verifying endotracheal tube placement, and assessing cuff-related tracheal wall pressure. The advent of point-of-care airway US can enhance patient safety by uncovering anatomical modifications that impede ventilation or intubation. To maximize its utility, standardized protocols and training are needed so that airway becomes an accessible, reliable component of perioperative and critical care practice.