BACKGROUND: From our clinical experiences, there are some problems with a paratracheal stellate ganglion block at the 6^th cervical level e.g. small changes in blood flow to the upper extremities and more difficulty in differentiating sympathetically-maintained pain from neuropathic pain. This study compared the effectiveness of the classic injection technique and the modified injection technique in paratracheal stellate ganglion block at the 6^th cervical level.

METHODS: Forty patients were randomly divided into 2 groups. In Group I, the patients underwent a paratracheal stellate ganglion block at the 6^th cervical level with 1% mepivacaine 6 ml using the classic injection technique. In Group II, the patients underwent a paratracheal stellate ganglion block at the 6^th cervical level with 1% mepivacaine 6 ml using the modified injection technique by applying strong pressure to the cephalad portion of the needle entry point. The skin temperature of the first finger was measured before and after the stellate ganglion block, and the warm sensation on the face and upper extremities, hoarseness and upper extremity paralysis were examined.

RESULTS: The increase in skin temperature of the first finger after the procedure was 0.26 ± 0.22 ℃ in Group I and 0.84 ± 0.63 ℃ in Group II, which was statistically significant (P < 0.05). There were no significant differences in the warm sensation on the face and upper extremities, hoarseness and upper extremity paralysis between the two groups.

CONCLUSIONS: The modified injection technique is more effective in the sympathetic block on the upper extremities than the classic injection technique.