Intravenous infusion of dexmedetomidine amplifies thoracic epidural analgesic effect after open thoracotomy A prospective, double-blind, randomized controlled trial

Background: The anesthetic-sparing effect of dexmedetomidine has led to its use as a general adjuvant. The present study aimed to determine intravenous infusion of dexmedetomidine to epidural analgesia after open thoracotomy. Methods: Forty-four patients scheduled for admission to the intensive care unit after open thoracotomy were divided into 2 groups. An epidural catheter was placed at T4 to T7. Thirty minutes before the end of thoracotomy, group D was injected with 0.3 mu g/kg/h of dexmedetomidine and group C received an equal dose of normal saline. For patient-controlled epidural analgesia (PCEA), 150mL of levobupivacaine 300mg was infused at a rate of 1mL/h, plus a bolus dose of 3mL with a lockout time of 30minutes. The primary outcome evaluated was analgesic efficacy using a visual analog scale (VAS) 48hours postoperatively. Other outcomes included additional analgesic use, total consumed local analgesia via PCEA, sedation score, blood pressure, heart rate, arterial blood gases, patient satisfaction, and adverse effects. Results: The VAS scores in group D were significantly lower than that in group C immediately, 1, 4, 12, 36, and 48hours after admission to the intensive care unit (P = .016, .009, .015, .002, .001, and .042, respectively). The total dose of additional analgesic was also significantly lower in group D (P = .011). Patient satisfaction was higher in group D (P < .05). There were no significant differences in the other outcomes between groups. Conclusion: Intravenous infusion of dexmedetomidine amplifies thoracic epidural analgesic effect after open thoracotomy.