Fig. 2

Stellate ganglion block process. A: The tip of the needle reached the surface of the longus colli muscle and the 5 o’clock position of the carotid artery. B: After administration of ropivacaine, the carotid artery can be seen floating like a balloon in real time under ultrasound, which indicates that the ropivacaine diffuses in the paravertebral space and can effectively block the stellate ganglion. 1, common carotid artery; 2, longus colli muscle; The three arrows indicate the puncture needle, and the two-way arrows indicate that the distance between the common carotid artery and the longus colli muscle is larger than that in Fig. A