Ultrasound-guided Thyroid Cartilage Plane Block for Awake Intubation

Use a SonoSite high-frequency linear array transducer (5-13 MHz, SonoSite, USA). Place the transducer parallel to the spine on one side of the neck, ensuring clear visualization of the thyroid cartilage plate under ultrasound. Employ ultrasound-guided out-of-plane techniques to display the needle insertion path and tip. Once the needle tip contacts the upper half of the thyroid cartilage plate, injecting 2.5ml of 2% lidocaine on the surface of the thyroid cartilage each side.