The Effect of Epidural Infusion of Dexmedetomidine on Postoperative Analgesia After Thoracotomy: A Randomized Clinical Trial

Background: The unique analgesic properties of dexmedetomidine have led anesthesiologists to use it as an alternative to relieve pain after major surgeries. Objectives: We aimed to evaluate the effect of continuous injection of thoracic epidural dexmedetomidine on analgesia after thoracotomy. Methods: In this randomized, double-blind clinical trial, 46 patients (18 to 70 years old) who were candidates for thoracotomy surgery were randomly assigned to receive ropivacaine alone or combined with dexmedetomidine after epidural anesthesia as postoperative epidural anesthesia. The postoperative sedation rate, pain score, and opioid use were assessed within 48 hours after surgery and compared between the 2 groups. Results: Comparing the mean postoperative sedation scores indicated no difference between the 2 study groups. The pain score assessment showed a lower pain score 6 to 36 hours after surgery in the group receiving concurrent ropivacaine and dexmedetomidine than in the group receiving ropivacaine alone. In the 2 groups receiving ropivacaine with and without dexmedetomidine, the rate of morphine administration after surgery was 43.4% and 65.2%, respectively, indicating no difference. However, the first group received significantly lower doses of morphine after the end of surgery (3.26 ± 0.90 mg vs. 7.04 ± 1.48 mg; P = 0.035). Conclusions: A combination of ropivacaine and dexmedetomidine as epidural analgesia can lead to lower postoperative pain scores and reduced doses of opioids required.