Effects of dexmedetomidine plus ropivacaine in ultrasound-guided brachial plexus upper trunk and superficial cervical plexus nerve block in shoulder arthroscopic surgery

Objective The addition of dexmedetomidine (Dex) to local anesthetics can prolong peripheral nerve block. However, clinical safety data on the brachial plexus upper trunk and superficial cervical plexus block are limited. We compared the efficiency of ropivacaine combined with Dex to efficiency of ropivacaine alone in the ultrasound-guided brachial plexus upper trunk and superficial cervical plexus block during shoulder arthroscopy. Methods A total of sixty patients with rotator cuff injury, ASAⅠor Ⅱ were enrolled. The patients underwent single shoulder arthroscopy, with ultrasoundguided brachial plexus upper trunk and superficial cervical plexus block combined with general anesthesia. Patients were randomly divided into two groups: group D (ropivacaine alone) and group E (ropivacaine combined with Dex), 30 patients in each group. After successful ultrasound-guided puncture, in the group D, 0.35% ropivacaine (12 ml) was injected in each patient while 0.35% ropivacaine combined with 1 μg/kg of Dex (12 ml) was injected in patients of the group E. Before the operation (T0), 5 min after the operation (T1), 30 min after the operation (T2), and 30 min after removal of the laryngeal mask (T3), HR, MAP and SpO2 were recorded. Operation duration, time of laryngeal mask removal (from stopping sevoflurane to removal of laryngeal mask), dosage of opioid analgesic (sufentanil), the amount of sevoflurane, VAS at 6, 12, 18, 24 h after surgery, and side effects such as hypertension, hypotension, tachycardia, bradycardia, nausea, and vomiting were recorded. Results The differences in age, gender, weight, ASA classification, BMI, operation time, intraoperative fluid intake, BIS value of T1 and T2 between the two groups were not statistically significant (P>0.05). Compared with the group D, the dosage of sufentanil and sevoflurane in the group E was significantly reduced (P<0.05). T1-T3 MAP and T3 HR was significantly lower (P<0.05). And VAS score was significantly lower 6, 12 h and 18 h after surgery (P<0.05). Two cases of bradycardia occurred in group E, which was significantly higher than group D (P<0.05). No side effects such as hypertension, hypotension, tachycardia and postoperative nausea and vomiting occurred in the two groups within 48 h after resuscitation. Conclusions In the treatment of shoulder arthroscopy under ultrasound-guided brachial plexus upper trunk and superficial cervical plexus block combined with general anesthesia, ropivacaine combined with Dex can reduce the dosage of sufentanil and sevoflurane, provide a more stable state of anesthesia at the same time and prolong postoperative analgesia time, when compared with ropivacaine alone. Key words: Brachial plexus upper trunk nerve block; Superficial cervical plexus nerve block; Ropivacaine; Dexmedetomidine; Shoulder joint; Arthoroscopy