Xia F, et al. - Given dexmedetomidine (Dex) has been shown to prolong the duration of analgesia when added to local anaesthetic as an adjuvant in a central or peripheral nerve block, researchers performed this prospective, double-blinded, randomized study to test their hypothesis that intrathecal (IT) Dex can reduce the 95% effective dose (ED95) of spinal hyperbaric bupivacaine. They determined the ED95 of IT hyperbaric bupivacaine for the Dexmedetomidine group (received bupivacaine + 5 mcg dexmedetomidine) and the Control group (received bupivacaine + the same volume of saline). For the Dex group and Control group, the reported ED95 and 95% confidence intervals (95% CI) of IT hyperbaric bupivacaine were 8.4 mg and 12.1 mg, respectively. Overall, for patients undergoing caesarean section, hyperbaric bupivacaine antinociception was potentiated by 31% in spinal anaesthesia by IT 5 mcg dexmedetomidine.