A Comparative Study of Bilateral Erector Spinae Block Versus Intravenous Dexmedetomidine for Perioperative Pain Management in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting - A Single-Blind Randomized Controlled Trial

Abstract

Regional analgesia, along with general anesthesia, reduce postoperative pain. In this study, the authors compared the erector spinae plane (ESP) block having dexmedetomidine as an adjuvant with conventional pain management along with intravenous dexmedetomidine. Prospective randomized single-blinded trial. Tertiary care teaching hospital. All of the patients scheduled for elective off-pump coronary artery bypass grafting with an ejection fraction of >45%. After obtaining institutional ethical committee approval, 130 patients were randomized into Group E and Group D. Group E patients received ESP block bilaterally with 25 mL of bupivacaine plus 0.5 μg/kg of dexmedetomidine. The patients in Group D received conventional intravenous analgesia, as well as a 0.7 μg/kg of dexmedetomidine bolus, followed by a 0.3 μg/kg dexmedetomidine infusion during surgery and continued postoperatively for 24 hours. Group E patients received 8 mL/h of bupivacaine infusion bilaterally for 24 hours. The primary outcome assessed was pain scores in the postoperative period. The secondary outcomes assessed were postoperative rescue analgesic consumption, time to first rescue analgesia, intraoperative fentanyl consumption, duration of mechanical ventilation, and duration of intensive care unit (ICU) stay. Both groups were comparable in demographic characteristics. The postoperative pain scores from 4 hours to 12 hours were lower in Group E compared with Group D. The pain scores at 24 hours were not significantly different between groups. Postoperative fentanyl consumption in Group E (99.23 ± 50.19 μg) was significantly lower than in Group D (181.15 ± 82.92 μg), with a p value of 0.001. Time to first rescue analgesia was significantly longer in Group E, with a median score of 8 hours when compared with that of 4 hours in Group D, with a p value of 0.01. Intraoperative fentanyl consumption was significantly lower in Group E (392.15 ± 55.36 μg) compared with Group D (604.00 ± 131.87 μg; p=0.001). There were no significant differences in the duration of mechanical ventilation in both groups. Duration of ICU stay was significantly lower in Group E (51.95 ± 8.54 hours) when compared with Group D (59.06 ± 8.68 hours) (p=0.001). Erector spinae fascial plane blocks appeared to reduce postoperative pain scores in off-pump coronary artery bypass graft patients. Furthermore, ESP block was beneficial in terms of less intraoperative and postoperative opioid consumption, longer time to first rescue analgesia, and shorter ICU stay.