Effect of Intrathecal Dexmedetomidine in Preventing Intra-operative Shivering after Spinal Anesthesia

Background: Dexmedetomidine (DEX) has sedative, analgesic, sympatholytic, anesthetic-sparing and hemodynamic-stabilizing properties. This study aims to evaluate the effects of intrathecal DEX as an adjuvant to hyperbaric bupivacaine in the prevention of shivering in patients who underwent surgeries under Intrathecal anesthesia.

Methods: A prospective double-blind, controlled, randomized study was conducted on 100 patients aged above 21 years old, ASA I & II undergoing lower limb orthopedic surgeries under intrathecal anesthesia. Patients were subdivided randomly into 2 equal group; Group Bupivacaine-Dexmedetomidine (BD): 5 µg dexmedetomidine diluted in 0.5 ml 0.9% normal saline was added to 12.5 mg heavy bupivacaine 0.5% and Group Bupivacaine (B): 0.5 ml 0.9% normal saline was added to 12.5mg heavy bupivacaine 0.5% (3ml volume).

Results: Shivering occurred in 9 patients (18%) in group BD and 23 patients (46%) in group B with a significant decrease in group BD compared to group B (P = 0.003). The relative risk of developing shivering was decreased 53% (95% Confidence Interval: 74 – 16%) with group BD compared to group B. Tsai and Chu score was significantly better in group BD (P = 0.013).

Conclusion: The use of intrathecal DEX (5μg) in conjugation with heavy bupivacaine help decrease the incidence and intensity of shivering when compared with heavy bupivacaine alone in surgeries under spinal anesthesia.