Abstract
Role of dexmedetomidine as adjuvant to intrathecal local anaesthetics is being increasingly described in the literature. This prospective, double blind, randomised study evaluated various doses of dexmedetomidine with an aim to find out the dose of dexmedetomidine. Patients undergoing elective vaginal hysterectomy were randomly divided into 5 groups of 16 patients each. Group 1 (control) received 3 ml of 0.75% isobaric ropivacaine. Group 2, 3, 4 and 5 received additional 3, 5, 10 and 15 µg dexmedetomidine respectively. Compared to control, onset of sensory block was quickened in all in groups except in group 2, while onset of motor block was quickened in all groups except groups 2 and 3. Sensory 2 segment regression, regression of sensory block to S2, time to regression of motor block to modified Bromage score 0 and time to 1st analgesic request was prolonged in all the test groups. Maximum Visual analogue score and total postoperative analgesic requirement was lower in all test groups when compared to control. No difference was observed between group 4 and 5 when they were compared in terms of onset or duration of sensory and motor block or post-operative analgesia. However, group 5 had higher incidence of hypotension and bradycardia and required higher dose of ephedrine and atropine than other groups. Dexmedetomidine in a dose of 10 µg is preferable to other doses in terms of balance between potentiation of subarachnoid block and development of undesirable effects.
Keywords: dexmedetomidine, spinal anesthesia, dose, anesthesia.
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Corresponding Author
Dr Rati Prabha
Department of Cardiac Anesthesia
LPS institute of Cardiology, Kanpur India
Mobile No. 9452781293, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
DOI: https://dx.doi.org/10.18535/jmscr/v6i2.179
