AbstractBackground: Intravenous regional anesthesia (IVRA) was introduced into clinical practice by August Bier in 1908. This form of analgesia is ideally suited for emergencies, where patient is with full stomach or suffering from other diseases that contraindicates general anaesthesia, moreover the feasibility and simplicity of execution of this method, its effectiveness and its lack of any side effects have been gratifying. IVRA is particularly suitable for day care surgeries as it requires minimal preparation and premedication. Dexmedetomidine, a stereoisomer of medetomidine is a highly selective alpha 2 adrenergic agonist and has been shown to decrease anesthetic requirements by upto 90% and to induce analgesia in rats, volunteers and patients. The present study was designed to evaluate the quality, onset and recovery of IVRA with 0.5mcg/kg dexmedetomidine added to 3mg/kg of 0.5% lignocaine.
Methods: After institutional approval and informed consent, 60 ASA 1 and 2 volunteers, were taken into the study. In Group A 30 patients were randomly allocated to receive IVRA for upper limb with 3mg/kg for 0.5% lignocaine; in Group B 30 patients randomly received IVRA of upper limb with 3mg/kg of 0.5% lignocaine with 0.5mcg/kg Dexmedetomidine. The onset and recovery of sensory block were tested in six sites of the forearm and hand, determined by pin prick, touch and cold. The cuff was released after 45 minutes.Theonsetofcompletemotorblockwasalsoassessedandanysymptomsaftercuffde!ationwere recorded. Usual haemodynamic monitoring was used.
Results: The speed of onset of sensory and motor block was higher in Group B than in Group A (p<0.05). The recovery of sensory and motor block was prolonged in Group B than in Group A (p<0.05). The tourniquetpainoccurredsigni#cantlylaterinGroupBascomparedtoGroupA.Therewerefewincidence of bradycardia in Group B.
Conclusion: Addition of 0.5mcg/kg of Dexmedetomidine as an adjuvant to Bier’s Block effectively enhances the anesthesia and post-operative analgesia obtained with lignocaine. The low dose of Dexmedetomidine was effective and did not cause any major side-effects.