Background: Perioperative shivering is one of the most common problems in parturients receiving regional anesthesia during cesarean section. Although shivering is a protective reflex to increase the core temperature by involuntary contraction of muscles, it also leads to adverse effects like increasing oxygen consumption and affecting wound healing. The aim of this work is to compare the efficacy of dexamethasone and dexmedetomidine in prevention of perioperative shivering when added to hyperbaric bupivacaine intrathecally in cesarean sections (CS) and their effect on the intraoperative hemodynamics, intensity of the block, sedation, and postoperative analgesic requirement. Results: Study included 60 obstetric patients who were randomized into 2 equal groups, each consisting of 30 patients, namely group A (dexmedetomidine group and B (dexamethasone group). Group A patients received 5 μg dexmedetomidine with 12.5 mg hyperbaric bupivacaine 0.5% intrathecally. Group B patients received 8 mg dexamethasone then 12.5 mg hyperbaric bupivacaine 0.5% intrathecally. The comparison included assessment of intra- and postoperative hemodynamics, duration of surgery, assessment of sensory and motor block, assessment for shivering and sedation, and assessment of adverse events. This study showed that there were a small number of patients complaining of shivering (five patients in group A and seven patients in group B) with no statistical difference between both groups in the incidence and intensity of shivering. Time to two segment regression (minutes) was longer in group B compared to group A, and also, time to first analgesic rescue was longer in group B compared to group A. For sedation intensity, there was statistical difference between both groups as all patients in group A were sedated compared to six patients only in group B. There was no statistical difference between both groups as regards incidence of adverse effects. Conclusion: We concluded that both drugs can be added safely to bupivacaine, and both decreased the incidence and the intensity of shivering. Dexamethas one was found to prolong the duration of sensory block and delay opioid requirements post-operatively, while dexmedetomidine is more effective in sedating the patients intra- and postoperatively.
