Thyroid Cartilage Plane VS Superior Laryngeal Nerve Space Block in Awake Tracheal Intubation

The aim of this clinical trial is to compare the effectiveness and safety of ultrasound-guided thyroid cartilage plane approach with the superior laryngeal nerve space approach for superior laryngeal nerve block in awake tracheal intubation. Patients were randomized into the thyroid cartilage plane block group (T group) or the superior laryngeal nerve space block group (C group). In Group T, bilateral thyroid cartilage plane block was performed under ultrasound with thyroid cartilage as the landmark, and local anesthetic was injected on the surface of the thyroid cartilage. In Group C, local anesthetic was injected into the space between the thyrohyoid membrane and muscle groups above. The investigators aim to evaluate whether the thyroid cartilage plane approach is not inferior to the superior laryngeal nerve space approach for ultrasound-guided superior laryngeal nerve block in awake tracheal intubation