Evaluation of Temperature Elevation on the Ipsilateral Upper Extremity after T2 Paravertebral Block

Moon, Dong Eon; Lee, Jaemin; Kim, Eun Sung; Moon, Seok Whan

Abstract

BACKGROUND
A thoracic paravertebral block is effective at treating unilateral pains of the arm, chest, and abdomen. In when administering a thoracic paravertebral block it is essential to know whether the sympathetic block is complete. The aim of the present study was to evaluate sympathetic denervation after a T2 paravertebral block by measuring the skin temperature of the ipsilateral upper extremity. METHODS: Eleven patients scheduled for video-assisted thoracoscopic sympathectomy for palmar hyperhydrosis were selected for this study. Right side T2 paravertebral block was performed with 8 ml of 2% lidocaine using a 22-gauge needle under fluoroscopic guidance. Bilateral skin temperatures were measured on both middle finger tips before block, and 1, 3, 5, 7, 10 and 15 minutes after injecting 8 ml of 2% lidocaine. RESULTS: The ipsilateral skin temperatures significantly increased with time after T2 paravertebral block administration. Contralateral skin temperatures were increased after the block, but this was not statistically significant. Mean depths from the skin to the transverse process of T2 and from the transverse process to the paravertebral space were 3.75 +/- 1.25 cm, and 1.0 +/- 0.23 cm respectively. Mean denervated dermatomes were 3.63 +/- 1.32 after paravertebral block. CONCLUSIONS: This clinical study reveals that a single-site injection of 8 ml of 2% lidocaine produces multidermatomal ipsilateral somatic and sympathetic nerve block. We ascertained that the T2 paravertebral block is effective for adequate sympathetic blockade of the upper extremity.