Intravenous regional anesthesia: comparing efficacy of magnesium sulphate and clonidine as an adjuvant to lignocaine for intraoperative and postoperative analgesia.

Abstract

Objectives: Intravenous regional anesthesia is used for short procedures for hand and upper limb surgeries. IVRA with adjuvants like opioids, muscle relaxants, NSAIDS increases the efficacy in terms of analgesic duration and quality of anesthesia. We conducted this comparative study for evaluating the effect of adding magnesium sulphate and clonidine with lignocaine in IVRA for upper limb surgeries.
Methodology: Seventy five patients ASA class 1 and 2 of either sex, age 18-60 years undergoing upper limbs surgeries were enrolled. They were divided into three groups (25 each) according to drug received. Group L: 9 ml of 2% lignocaine (preservative free) diluted with normal saline to make a total volume of 36 ml of 0.5% lignocaine. Group M: 3 ml of 50% magnesium sulphate with 9 ml of 2 % lignocaine diluted with normal saline to make a total volume of 36 ml, 0.5% lignocaine. Group C: 1 µg/kg clonidine with 9 ml of 2% lignocaine diluted with normal saline to make a total volume of 36 ml of 0.5% lignocaine. Sensory and motor block (onset and recovery time), intraoperative tourniquet pain, time to first tramadol requirement and mean tramadol dosage, quality of operative conditions, hemodynamic parameters,  postoperative pain (VAS) scores were recorded.
Results: Both groups were comparable in terms of age, sex, ASA grade, baseline hemodynamic parameters, duration of surgery and tourniquet inflation time. Shortened sensory and motor block onset times were established in Group M (p < 0.05). Recovery from sensory and motor blockade was significantly prolonged in Group M (p < 0.05). Anesthesia excellence as determined by anesthesiologist and the surgeon was significantly better in C group as compared to rest two groups (p < 0.05).There was statistically significant difference (p > 0.05) in intraoperative VAS in Group M and C as compared to Group L, throughout the procedure. Time to First analgesic requirement in Group C 43.04 ± 27.46, Group M 42.72 ± 18.06 and Group L was 27.08 ± 4.45  minutes (p < 0.05). Postoperative VAS scores for 24 hours were higher in Group L as compared to Group M and C (p < 0.05).