Evaluation of new approach to ultrasound guided stellate ganglion block

Abstract

Background: Ultrasound imaging is an ideal tool for stellate ganglion block (SGB) due to clarity, portability, lack of radiation, and low cost. Ultrasound guided anterior approach requires the application of pressure to the anterior neck and is associated with more risk of injury to inferior thyroid artery, vertebral artery, and esophagus. The lateral approach does not interfere with nerve or vascular structures. Blockade at the C 6 vertebral level results in more successful sympathetic blockade of the head and neck with less sympathetic blockade of the upper extremity compared to sympathetic blockade at C 7 vertebral level, which produces successful sympathetic blockade of upper extremity. This is helpful in patients of complex regional pain syndrome of the upper limb. Hence, we conducted a study using the lateral approach at C 7 level. Materials and Methods: Ultrasound guided SGBs using lateral in-plane technique at C 7 level were given in 20 patients suffering from chronic pain patients of upper extremity, head, and neck using 4 ml of 0.25% bupivacaine and 1 ml of 40 mg triamcinolone. The patients were assessed for a numeric pain intensity score (NPIS), the rise in axillary temperature, the range of motion of joints of upper extremity, and resolution of edema at various time intervals up to 3 months. Results: NPIS showed a statistically significant decrease from baseline at 30 min, which was sustained till 3 rd month. The rise in axillary temperature after the block was statistically significant, which was sustained till 2 nd week. The edema score decreased significantly at all-time intervals (P ≤ 0.001). The restriction of motion in all joints of upper limb decreased from 13 to 3 patients. Conclusion: There is a significant variation in the anatomy of stellate ganglion at the level of C 6 and C 7 . Ultrasound guided lateral approach increases the efficacy of SGB by deposition of drug subfascially with real-time imaging.

Keywords

• Complex regional pain syndrome; lateral approach; stellate ganglion block; ultrasound guidance