Comparative study between the effect of Intravenous versus Intrathecal Dexmedetomidine as an Additive to Hyperbaric Bupivacaine in Spinal Anesthesia for Hip Arthroplasty

Background: A lot of people who were getting hip arthroplasty (HA) were given spinal anesthesia. This might have helped with pain management and preventing embolism of the deep veins in the early days after surgery.Aim and objectives: To find out whether intravenous (IV) or intrathecal (IT) dexmedetomidine works better and is safer when added to spinal anesthesia with hyperbaric bupivacaine for adult HA patients.Patients and Methods: Seventy participants participated in this single-blind, prospective, randomized, controlled study at the Al-Azhar University Hospitals for Boys in Cairo, conducted from May 23 to May 24. Participants were divided into two equal groups: 12.5 mg (2.5 ml) of hyperbaric bupivacaine 0.5% was administered to Group A along with 5 μg of attenuated dexmedetomidine in 1 ml of normal saline IT. Group B received 12.5 mg (2.5 ml) of hyperbaric bupivacaine, 0.5% combined with 1 ml of normal saline intravenous (IV) for spinal anesthesia, and 0.5 μg/kg of diluted dexmedetomidine administered slowly.Results: The intrathecal group showed a significantly longer duration of motor 228.03 ± 52.8 minutes vs 163.4 ± 39.26 minutes, P<0.001) and an insignificant difference of duration for sensory block (238.69 ± 53.91 minutes vs 253.29 ± 53.69 minutes, P>0.05) compared to the intravenous group. In the IT group, both motor and sense blocks start more quickly. In the first 24 hours after surgery, patients in the IT group needed fewer extra painkillers (P=0.01). There isn't a big change in MAP, but the IV group has more cases of bradycardia (P<0.05).Conclusion: When combined with hyperbaric bupivacaine for spinal anesthesia, both IV and IT dexmedetomidine were safe and effective; however, in adult patients receiving HA, IT dexmedetomidine was more efficient as an analgesic and provided motor block than IV dexmedetomidine.