THE STUDY OF EFFECT OF DEXMEDETOMIDINE ON THE CHARACTERISTICS OF BIER???S BLOCK (INTRAVENOUS REGIONAL ANAESTHESIA) WHEN ADMINISTERED IN ADDITION TO LIDOCAINE FOR FOREARM AND HAND SURGERIES

Abstract

Diptanu Bhaumik1, Amol Singam2, Nand Kishore Agrawal3

BACKGROUND
Bier’s Block (IVRA) is being commonly used as anaesthetic technique for conducting forearm and hand surgeries. It is technically simple and reliable with success rate between 94-98%. However, its use is limited by tourniquet pain and inability to provide postoperative analgesia. To improve the quality of Bier’s block, the addition of α-2 adrenergic receptor agonist, dexmedetomidine have been the focus of interest for their sedative, analgesic and perioperative sympatholytic and cardiovascular stabilising effects. The aim of the present study was to evaluate the efficacy of 0.5 mcg/kg dexmedetomidine when added to (0.5%) lidocaine (40 mL) with lidocaine alone in IVRA.
MATERIALS AND METHODS
After approval from Institutional Ethical Committee, 60 patients of ASA Grade I and II of either sex aged between 20-60 years scheduled for various forearm and hand surgeries were included in the study. Patients were randomly divided into two groups 30 in each. Patients in Group L received (0.5%) lidocaine 40 mL with 1 mL NS making it to a total volume of 41 mL and Group LD received (0.5%) lidocaine with the test drug, 0.5 mcg/kg dexmedetomidine diluted up to 1 mL NS to a total volume of 41 mL. Both sensory and motor block onset and regression times, incidences of tourniquet pain, haemodynamic changes, quality of block were noted. Sedation score using Ramsay sedation scale, duration of postoperative analgesia and associated complications were also recorded. Intraoperative and postoperative pain score was recorded by using VAS. Rescue analgesia was given when VAS >3.
RESULTS
Significant shorter onset times and prolonged regression times of sensory and motor block were recorded in Group LD as compared to Group L. Better haemodynamic stability, prolonged tourniquet tolerance and improved quality of anaesthesia were found in Group LD. Time to first analgesic requirements was significantly longer in Group LD in the postoperative period.
CONCLUSION
We concluded that addition of 0.5 mcg/kg dexmedetomidine to (0.5%) lidocaine for IVRA improves quality of anaesthesia, tourniquet pain and postoperative analgesia without causing side effects.

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