Alpha 2 agonists in regional anesthesia and analgesia

Effect of Clonidine and/or Fentanyl in Combination with Intrathecal Bupivacaine for Lower Limb Orthopedic Surgeries in Spinal Anaesthesia

“…Intrathecal clonidine has been reported to result in intraoperative hypotension. 30,31 However, we observed stable hemodynamics among all the groups without any incidence of respiratory depression. This could be explained by adequate preloading which was performed in all the patients prior to subarachnoid block.…”

“…Clonidine is known to cause sedation, and this hypnotic response is believed to be mediated via locus coeruleus where alpha-2-adrenergic receptors are abundant. 31 A potential limitation of our study design relates to small sample size. Secondly, we did not attempt dose-response effect by using various doses of clonidine.…”

Comparative Study of Epidural Dexmedetomidine with Clonidine as Adjuvant to Isobaric Ropivacaine in Abdominal Hysterectomy

“…Discussion α-2 agonists provide sedation, analgesia, anxiolysis, hypnosis, sympatholysis, improve quality and cause less respiratory depression when used as adjuvant in epidural anesthesia. [5][6][7][8] Dexmedetomidine is eight times more specific and highly selective α-2 adreno receptor agonist compared to clonidine. 9,10 There are no studies indicating the equipotent doses of epidural dexmedetomidine and clonidine.…”

“…1 The stable haemodynamics and the decreased oxygen demand due to enhanced sympathoadrenal stability, less thromboembolic events and other complications make them very useful pharmacologic agents. 2,3,4 Dexmedetomidine has anα-2 affinity eight times greater than clonidine.…”

Clonidine versus butorphanol as adjuvant to 0.5% hyperbaric bupivacaine to enhance the onset and duration of subarachnoid blockade with postoperative analgesia during orthopaedic surgeries-A randomized study

“…Anti-nociceptive synergism between local anesthetic and intrathecal adjuvants, opioids or α 2 agonist, allow the reduction in the dosages of both drugs, reduce the unwanted side effects attributable to both drugs and improves the perioperative analgesia [2][3][4].…”