Summary

Suprascapular nerve block and axillary nerve block with dexmedetomidine improved visual analog pain scale patient satisfaction within 48 h after arthroscopic rotator cuff repair. Pain-related cytokines showed some differences associated with dexmedetomidine within this period. A delayed rebound pain happened in the group treated with dexmedetomidine.

Abstract

Introduction

Suprascapular nerve block (SSNB) is most commonly used for relieving postoperative pain of arthroscopic rotator cuff repair and it can be used in combination with axillary nerve block (ANB). Dexmedetomidine (DEX) is known as a type of alpha agonist which can elongate the duration of regional block. The aim of this study was to compare the results of dexmedetomidine combined with SSNB and ANB with SSNB and ANB alone on postoperative pain, satisfaction, and pain-related cytokines within the first 48 hours after arthroscopic rotator cuff repair.

Methods

40 patients with rotator cuff tears who had undergone arthroscopic rotator cuff repair were enrolled in this study. The 20 patients randomly allocated to group 1 received ultrasound-guided SSNB and ANB using each mixture of 0.5 ml (50 µg) DEX and 9.5 ml 0.75% ropivacaine, preemptively. The other 20 patients to group to group 2 underwent ultrasound-guided SSNB and ANB alone using each mixture of 0.5 ml normal saline and 9.5 ml ropivacaine. Functional scores were checked at postoperative 1, 3, 6, 12, 18, 24 and 48 h. Plasma Cortisol, interleukin (IL) -6, IL-8, IL-1b, and Serotonin were measured at postoperative 1, 6, 12, 24 and 48 h.

Results

Group 1 showed a significantly lower mean VAS (Visual analog scale of pain) at postoperative 1, 3, 6, 12, 18 and 24 h, and a significantly higher mean SAT (Patient's satisfaction) at postoperative 1, 3, 6, 12, 18, 24 and 36 h than group 2. Group 1 showed a significantly lower mean plasma IL-8 at postoperative 1 and 48 h, and a significantly lower mean IL-1ß at 48 h than group 2. Group 1 showed a significantly lower mean plasma Serotonin at postoperative 12 h than group 2. Six patients in each group 1 and group 2 showed the rebound pain one time. The others did not show the rebound pain.

Conclusion

Ultrasound-guided SSNB and ANB with DEX improved VAS and SAT within postoperative 48 h. Pain-related cytokines showed some differences associated with DEX. A delayed rebound pain happened in the group treated with DEX.
Level of evidence: Level I, randomized controlled trial.