Objective: Arthroscopic subacromial decompression may cause substantial postoperative pain. We undertook a randomized controlled trial to examine whether adding dexmedetomidine to the local anesthetic in an interscalene brachial plexus block and subsequent patient-controlled interscalene analgesia (PCIA) regime improved postoperative pain scores, patient satisfaction, rescue analgesic requirement and local anesthetic consumption.
Methods: 48 patients aged between 18 and 65 years undergoing arthroscopic subacromial decompression were enrolled and randomized into one of two groups. Group L (n=25) received levobupivacaine and epinephrine while Group LD (n=23) received levobupivacaine, epinephrine and dexmedetomidine via an interscalene catheter. Four hours after surgery, a PCIA regime was commenced. In Group L patients were administered levobupivacaine and in Group LD levobupivacaine and dexmedetomidine. Demographic and hemodynamic data, duration of motor and sensory blocks, pain VAS, side effects, PCIA demand and delivery values, consumption of lornoxicam as a rescue analgesic and patient satisfaction were recorded for 24 hours after surgery.
Results: PCIA demand and delivery, and pain VAS values were significantly lower, and patient satisfaction was significantly higher in the dexmedetomidine group (P=0.004, 0.001, 0.004 and 0.002 respectively). The side effect profile was similar between the groups. Levobupivacaine consumption was significantly lower in Group LD (P=0.009). In the first 24 postoperative hours, Group LD consumed significantly less lornoxicam (P=0.01).
Discussion: Addition of dexmedetomidine to levobupivacaine for interscalene brachial plexus block decreases pain scores and increases patient satisfaction after arthroscopic subacromial decompression.
(C) 2014 by Lippincott Williams & Wilkins