Analgesic efficacy of the erector spinae plane block using bupivacaine vs. bupivacaine/magnesium sulphate in patients undergoing lumbar spine surgery: a randomized, double-blinded comparative study

Abstract

Background & Objectives: Postoperative pain is one of the most troublesome pains for the surgical patient, and is one of the causes of morbidity and prolonged hospital stay. Opiates and non-steroidal anti-inflammatory drugs have been routinely used across the world. Recent resurge of regional anesthetic techniques offer some advantages, especially reduced post-operative nausea and vomiting and less sedation. We compared the efficacy of bupivacaine with a combination of bupivacaine/magnesium sulphate for the Erector Spinae Plane (ESP) block in patients for postoperative pain undergoing lumbar spinal fusion under general anesthesia. Methodology: A total of 30 ASA-I and II patients, 20-60 y old, who undergoing lumbar spinal fusion were enrolled. They were randomly divided into two groups; Group B (n = 15) to receive bupivacaine 0.25 percent, 20 mL injected on each side to provide ESP block; and Group BMG (n = 15): to receive 20 mL of 0.25 percent bupivacaine plus 500 mg magnesium sulphate, injected on each side for ESP block. The parameters measured included; the surgery time, non-invasive mean blood pressure during surgery, postoperative heart rate at 1, 6, 12, and 24 h, The time to first request for analgesics time after surgery referred to as the postoperative period (h). Postoperative total analgesic (pethidine needed per 24h) required and postoperative pain at rest and on moving, measured with VAS (Visual Analogue Scale) at the 1st, 6th, 12th, and 24th h. Results: Both at rest and through moving the VAS (Visual Analogue Scale) among both groups. No significant difference could be seen at the first, sixth, twelfth, and twenty-fourth hours. The time to the first request for analgesics was significantly prolonged in the Group BMG than the Group B. The total analgesic need after surgery was significantly lower in Group BMG than the Group B. Conclusion: The use of a combination of bupivacaine plus magnesium for bilateral erector spinae plane block after lumbar spinal fusion surgery is better in terms of prolonged postoperative analgesia and reducing the opioid use as compared to bupivacaine alone in patients undergoing lumbar spinal fusion under general anesthesia.