Effects of administration of dexmedetomidine with intrathecal bupivacaine on analgesia after femoral and tibia orthopedic surgery: A double-blind randomized clinical trial study

Introduction: Various drugs are used as adjuvants for various purposes such as increasing analgesia, reducing analgesic complications and generally improving the quality of anesthesia with topical anesthetics. The use of alpha-2 agonists has recently been considered. One of these drugs is dexmedetomidine, which has been studied recently. The aim of this study was to evaluate the effect of dexmedetomidine as an adjunct to bupivacaine in spinal anesthesia in femoral fracture orthopedic surgery. Materials and Methods: This double-blind randomized clinical trial study was performed on 60 patients 18-50 years old with Class I and II anesthesia who were candidates for tibia and femur orthopedic fracture surgery. Patients were randomly divided into two groups of intervention: 12.5 mg bupivacaine (2.5 cc) and 5 µg dexmedomidine (0.5 ml) and control group: 12.5 mg bupivacaine and 0.5 ml normal saline. Systolic, diastolic, and mean arterial blood pressure and pulse counts were recorded before spinal anesthesia, after anesthesia and then every 15 minutes until surgery and at recovery time. At 2, 8, 4, 12, and 24 hours postoperatively, patients were evaluated for pain, opioid administration during the first 24 hours, and the time of first analgesic administration. Results: There was a significant difference between the bupivacaine-normal saline and bupivacaine- dexmedetomidine groups in terms of systolic and diastolic blood pressure at 15, 30, 45 and 60 minutes during surgery (P<0.05). There was a significant difference in the frequency of pain between the Bupivacaine-Normal Saline and Bupivacaine- dexmedetomidine groups at 4, 8 and 24 hours postoperatively (P<0.05). Conclusion: The results of this study showed that addition of 5 μg dexmedetomidine to bupivacaine in spinal anesthesia method prolonged analgesia time, decreased pain intensity, decreased postoperative opiate requirement. Conspicoiusly, there was no risk of respiratory suppression even at higher doses than other medicines used. Conclusively, dexamethasone seems to be an appropriate supplement to be added to bupivacaine to reduce postoperative pain.