Prospective study of ultrasound-guided peri-plexus interscalene block with continuous infusion catheter for arthroscopic rotator cuff repair and postoperative pain control.

Objective: This trial investigated postoperative analgesia in arthroscopic rotator cuff repair surgery patients under general anesthesia, associated with ultrasound-guided peri-plexus interscalene brachial plexus block (US-IBPB), and compared single injection to elastomeric pump continuous infusion of local anesthetics. Complications associated to both techniques are described.

Methods: In this prospective, quasi-randomized controlled clinical trial, 68 adults scheduled for elective arthroscopic rotator cuff repair were assigned to receive Group 1 (G1 = 41) US-IBPB with a 20 mL injection of 0.5% peri-plexus ropivacaine, introduction of catheter, injection of 20 mL of 0.5% ropivacaine through continuous catheter infusion of local anesthetic by elastomeric pump (ropivacaine 0.2%, infusion of 5 mL/h). In Group 2 (G2 = 27), US-IBPB, with a single peri-plexus injection of 40 mL ropivacaine 0.5%. In both groups oral analgesics were prescribed, paracetamol 500 mg associated to codeine 30 mg for patients with VAS between 3 and 5, and also oxycodone 20 mg for VAS ≥ 6. The anesthesiology team was available through contact telephones and the patients received a table to complete in order to report pain intensity according to VAS, use of oral medication, and complications related to the catheter and pump, until the third postoperative day.

Results: The intensity of pain was higher on second day after surgery than on days 1 and 3, in both groups confirmed by the ANOVA test ( p  = 0.00006) Among the groups, G1 patients had lower pain intensity than G2, ( p  = 0.000197). G2 patients presented greater pain intensity during all periods studied (days 1, 2, and 3) than G1 patients. Postoperatively, G2 patients had higher consumption of rescue analgesics, nausea, and vomiting (40.74%) vs. G1 (5%) and dizziness (25.92%). No patient with catheter and elastomeric pump (G1) had complications regarding its insertion and maintenance during postoperative period.

Conclusion: The quality of analgesia for arthroscopic rotator cuff repair with peri-plexus US-IBPB and continuous infusion with elastomeric pump presented superior postoperative analgesia quality to single puncture IBPB on postoperative days 2 and 3, with lower consumption of rescue opioids in this period.