Evaluation of Addition of Sodium Bicarbonate to Dexamethasone and Ropivacaine in Supraclavicular Brachial Plexus Block for Upper Limb Orthopedic Procedures

BACKGROUND: Peripheral nerve blocks have taken over as the principle technique for upper limb surgeries. A number of adjuvants have been tried individually, but very few studies have investigated the cumulative effect of two or more adjuvants given together along with local anesthetic. AIM: This study aimed to evaluate the effect of addition of sodium bicarbonate to dexamethasone and ropivacaine in supraclavicular brachial plexus block. SETTINGS AND DESIGN: This was a prospective, randomized, double-blind study that comprised 90 American Society of Anaesthesiologist (ASA) 1 and 2 patients posted upper limb orthopedic procedures. MATERIALS AND METHODS: Ninety ASA 1 and 2 patients were selected and divided into three groups of 30 each: Group R received 30 mL of 0.75% ropivacaine plus 4 mL normal saline; Group RD 30 mL of 0.75% ropivacaine, 2 mL normal saline and 2 mL of dexamethasone were given; Group RB 30 mL of 0.75% ropivacaine plus 2 mL of dexamethasone and 2 mL of sodium bicarbonate. Onset and duration of sensory and motor block and postoperative pain scores were studied in each group. STATISTICAL ANALYSIS: Student's independent t-test was employed for comparing the continuous variables and Chi-square test for the categorical variables. Kruskal–Wallis test was used for postoperative pain score data. RESULTS: Addition of sodium bicarbonate to dexamethasone and ropivacaine quickens onset and prolongs duration of sensory and motor block. CONCLUSION: Sodium bicarbonate produces a synergistic and potentiating effect with dexamethasone as adjuvant in supraclavicular brachial plexus block.