Introduction: The efficacy of local anesthetics in spinal anesthesia can be enhanced by using adjuvants like fentanyl, morphine, tramadol and α2-agonists like clonidine, dexmeditomidine so as to improve the postoperative patient comfort and satisfaction.

Aim: The present study was designed to study the analgesic efficacy and side effects of adding dexmedetomidine to bupivacaine in spinal anesthesia for gynaecological surgeries i.e hysterectomies.

Patients and Methods: In a prospective, randomized, double-blind study, after taking their informed consent, 60 patients were randomly divided into two groups of 30 each. Sub arachnoid block was given with 12.5 mg of 0.5% hyperbaric bupivacaine in group I (n = 30) and with 12.5 mg of 0.5% hyperbaric bupivacaine plus 5 μg of dexmedetomidine in group II (n = 30). The two groups were compared with respect to hemodynamic parameters, onset of sensory block to T10 and regression to S1, time to achieve Bromage 3 and regression to Bromage 0, duration of analgesia, number of doses and type of rescue analgesia required, and complications occurring in 24 h.

Results: Significant difference was observed in relation to onset of sensory block [12.7 ± 1.015 min in group I  and 6.84 ± 0.792 min in group II (P < 0.001)], total duration of sensory block [177.74 ± 28.573 min in group I and 353.36 ± 12.138 min in group II (P < 0.001)], total duration of motor block [146.94 ± 9.173 min in group I and 318.36 ± 9.374 min in group II (P < 0.001)], duration of analgesia [283.96 ± 11.165 min in group II and 126.34 ± 7.684 min in group I (P < 0.001)], and total number of doses of rescue analgesia required in 24 h [1.44 ± 0.501 in group II and 2.56 ± 0.675 in group I (P < 0.001)].

Conclusion: Addition of dexmedetomidine to bupivacaine in sub arachnoid block leads to early onset of sensory and motor block with prolonged duration, and patients remained pain free for a longer period with decreased demand for rescue analgesia in the postoperative period as compared with hyperbaric bupivacaine alone without addition of dexmeditomidine.

Keywords: bupivacaine, dexmedetomidine, intrathecal, subarachnoid block.

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Lt Col (Dr) Ritu Grewal

Classified Specialist (Anaesthesiology), Military Hospital Jaipur Rajasthan