Background:Alpha2-adrenergic agonists have synergistic action with local anesthetics and may prolong the duration of sensory, motor blockade and postoperative analgesia obtained with spinal anesthesia.Aim:The objectives of this study are to compare and evaluate the efficacy of intravenous dexmedetomidine premedication with clonidine and placebo on spinal blockade duration, postoperative analgesia and sedation in patients undergoing surgery under bupivacaine intrathecal block.Materials and Methods:In this prospective, randomized, double-blind placebo-controlled study, 75 patients of the American Society of Anesthesiologists status I or II, scheduled for orthopedic lower limb surgery under spinal anesthesia, were randomly allocated into three groups of 25 each. Group DE received dexmedetomidine 0.5 μgkg−1, group CL received clonidine 1.0 μgkg−1 and placebo group PL received 10 ml of normal saline intravenously before subarachnoid anesthesia with 15 mg of 0.5% hyperbaric bupivacaine. Onset time and regression times of sensory and motor blockade, the maximum upper level of sensory blockade were recorded. Duration of postoperative analgesia and sedation scores along with side effects were also recorded. Data was analyzed using analysis of variance or Chi-square test, and the value of P < 0.05 was considered statistically significant.Results:The sensory block level was higher with dexmedetomidine (T4 ± 1) than clonidine (T6 ± 1) or placebo (T6 ± 2). Dexmedetomidine also increased the time (243.35 ± 56.82 min) to first postoperative analgesic request compared with clonidine (190.93 ± 42.38 min, P < 0.0001) and placebo (140.75 ± 28.52 min, P < 0.0001). The maximum Ramsay sedation score was greater in the dexmedetomidine group than other two groups (P < 0.0001).Conclusion:Premedication with intravenous dexmedetomidine is better than intravenous clonidine to provide intraoperative sedation and postoperative analgesia during bupivacaine spinal anesthesia.

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Background:The peripheral nerve endings carrying pain contains opiod receptors. Blocking these receptors during haematoma block or periosteal block may provide better analgesia.Aim:Evaluation of effectiveness and safety of butorphanol as an adjuvant to lidocaine for haematoma block.Settings and Design:This is a two centre, prospective, individually randomised, two group, parallel, double-blind clinical trial.Methods:In this study, 115 American society of anaesthesiologist grade I and II adult patients scheduled for closed reduction of fractures were randomly allocated into two groups; Group A received 1% lidocaine (2 mg/kg) where as Group B received 1% lidocaine (2 mg/kg) with butorphanol (0.02 mg/kg) during haematoma block. Pain was assessed before, during and after manipulation of fracture by using visual analogue scale (VAS 0-10). Onset time of block, time for first rescue analgesic, 24 hour analgesic requirement and sedation levels were noted.Statistical Analysis:Data analysed with the unpaired t-test with Welch correction assuming unequal variances and Fisher's exact test using Graph pad Prism 5.02 version.Results:Onset time of haematoma block was significantly less in the butorphanol group compared to the lidocaine group (P=0.0003). The mean time for first rescue analgesic was significantly higher and total analgesic requirement was significantly lower in the butorphanol group (P<0.0001). Mean VAS scores were lower and sedation scores were higher in the butorphanol group.Conclusions:Addition of butorphanol to lidocaine quickens onset of haematoma block, provides excellent post manipulation analgesia and decreases 24 hour total analgesic requirement without excessive sedation.