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.

The effect of intra-articular meperidine and bupivacaine 0.5% on postoperative pain of arthroscopic knee surgery; a randomized double blind clinical trial.

BACKGROUND: Arthroscopic knee surgeries have a painful postoperative course, which often necessitates acute pain management. Among different analgesia techniques, Intra-articular injection is the technique of choice for many pain specialists, based on its confined effect to the surgical site (knee), lack of systemic effects and promotion of safe early ambulation. OBJECTIVES: The aim of this study was to compare analgesic effects of intra-articular meperidine, bupivacaine 0.5% or their combination after knee arthroscopic surgery. PATIENTS AND METHODS: Sixty ASA class I-II patients' candidates for arthroscopy knee surgery enrolled in a randomized double blind study to receive either 20 mL of bupivacaine 0.5%; 100 mg meperidine (diluted in normal saline) or bupivacaine 0.5% along with 100 mg meperidine. A written informed consent was obtained from all patients. Postoperative analgesia duration, VAS at 2, 6, 12 and 24 hours, the first analgesic request time, total fentanyl consumption in first 24 hours, patients' satisfaction and adverse effects were recorded. RESULTS: The bupivacaine-meperidine group had better duration of postoperative analgesia (P = 0.001), latter first analgesic request (P ≤ 0.001), lower total fentanyl consumption in first 24 hours after the operation (P = 0.001), less mean VAS at 2 hours (P = 0.001) and more patients' overall satisfaction (P = 0.01) compared with each medication alone. VAS at 6, 12 and 24 postoperative hours were not different between the groups of study. No adverse effects were observed. CONCLUSIONS: Although postoperative intra-articular meperidine is a better alternative for bupivacaine, their combination could improve their analgesic effects compared with each other alone.