Comparison of two different doses of intrathecal dexmedetomidine as adjuvant with isobaric ropivacaine in lower abdominal surgery

BACKGROUND: To augment the subarachnoid block utility, the efficacy of newer molecules as an adjuvant is investigated constantly. Considering the favorable profile of dexmedetomidine, it could have a potential role as an adjuvant to ropivacaine. AIM: We evaluated the efficacy of two different doses of dexmedetomidine as an adjuvant to isobaric ropivacaine, intrathecally. METHODS: Ninety patients scheduled for lower abdominal surgery under spinal anesthesia were randomized into three groups to receive 2.5 ml of isobaric ropivacaine (0.75%, 7.5 mg/ml) added to 5 µg (10 µg/ml) or 10 µg (20 µg/ml) of dexmedetomidine or 0.5 ml of normal saline in group A, B or C, respectively. Block characteristics were compared as a primary outcome. STATISTICAL ANALYSIS: One-way analysis of variance test, Fisher's exact test/Chi-square test, whichever appropriate. A P < 0.05 was considered significant. RESULTS: Time to achieve desired block was least in group B and maximum in group C. The sensory-motor blockade remained significantly prolonged in group B compared to other groups. Hemodynamic parameters remained stable in all three groups. CONCLUSION: Among the investigated doses, dexmedetomidine augments the efficacy of intrathecal ropivacaine in a dose-dependent manner, without any untoward side effects.