A Comparative Study between Intrathecal Dexmedetomidine vs Ketamine with Intrathecal Bupivacaine in Orthopedic Lower Limb Surgeries

This is the authors' abstract. We don't add key points for this paper.

Background: Many adjuvants have been used to increase the analgesic duration of intrathecal bupivacaine. Objective: This work was aimed at comparing intrathecal ketamine vs dexmedetomidine for patients with lower limb surgery regarding advantages, efficacies, and hemodynamic stability. Patients and methods: This prospective randomized double-blind study involved 100 individuals whose ages ranged from eighteen to fifty years, both sexes, who underwent orthopedic lower limb surgeries. All participants went through an even categorization into two groups: Group D: administering calculated dosage of intrathecal hyperbaric bupivacaine 0.5 % according to body weight and 5μg dexmedetomidine and Group K: administering calculated dosage of intrathecal hyperbaric bupivacaine 0.5 % according to body weight and 0.1 mg/kg of ketamine. Results: Intraoperative HR as well as MAP measurements were significantly higher during 15 min, 30min, 45min and end of surgery within group K as opposed to group D (P value <0.05). Postoperative HR, MAP, SaO2 as well as VAS measurements were significantly less during 30 min, 2h, 4h and 6h within group K as opposed to group D (P value <0.05). Time to first analgesic request was significantly delayed within group K as opposed to group D (P value<0.001). Complications (bradycardia as well as hypotension) were insignificantly varied among two groups. Respiratory depression occurrence was not present in both groups. Conclusions: Ketamine produces better analgesic outcomes compared to dexmedetomidine in patients with lower limb surgery. However, it is associated with higher intraoperative HR and MAP and lower postoperative HR and MAP compared to dexmedetomidine with no difference in complications among them.

May improve analgesia with intrathecal ketamine over dexmedetomidine in lower limb surgery; leaves open optimal dosing and safety in larger trials.