Effectiveness of additional thoracic paravertebral block in improving anesthetic effects of regional anesthesia for proximal humeral fracture surgery in elderly patients: study protocol for a randomized controlled trial
Abstract Background The innervation of shoulder-upper arm area is complicated and unclear. Ultrasound-guided brachial plexus combined with cervical plexus block is probably inadequate for the anesthesia of proximal humeral surgery. Missing blockade of T1-T2 nerves may be the reason. The primary aim of this trial is to investigate the effectiveness of additional T2 thoracic paravertebral block (TPVB) in improving the anesthetic effects of regional anesthesia for elderly patients in proximal humeral fracture surgery. Methods We have designed a two-armed, parallel, randomized controlled trial (RCT) to compare the anesthetic effects of ultrasound-guided brachial and cervical plexus block with or without additional T2 TPVB in terms of the following outcomes: success rate, sensory block and safety. The elderly patients over 65 years old, referred for anterior approach proximal humeral fracture surgery, will be enrolled. Each participant will be randomly assigned 1:1 to receive IC block (combined interscalene brachial plexus with superficial cervical plexus block) or ICTP block (combined thoracic paravertebral block with IC block). The primary outcome is the success rate of surgical anesthesia. The secondary outcomes are as follows: sensory block at surgical area, proportion of participants who need supplementary anesthesia (remifentanil or conversion to general anesthesia), cumulative doses of intraoperative vasoactive medications and adverse events. The necessary sample size is estimated to be 80 patients according to the data of our pilot study. Discussion This RCT aims to demonstrate that whether combined T2 TPVB with brachial and cervical plexus block can provide better anesthetic effects of regional anesthesia in elderly patients undergoing proximal humeral fracture surgery.