The use of intravenous magnesium sulfate on postoperative analgesia in orthopedic surgery

Abstract

Introduction:The aim of this systematic review is to investigate the effects of perioperative intravenous administration of MgSO4 on postoperative pain, analgesic consumption and adverse effects in patients undergoing orthopedic surgery.Methods:Two investigators independently searched for articles on randomized controlled trials (RCTs) from 1998 to 2016 in Pubmed, Web of science and Google scholar. We evaluated clinical outcomes, comparing postoperative pain scores, cumulative analgesic consumption, time to first analgesia, and adverse effects between orthopedic surgery patients with and without the administration of MgSO4.Results:After screening 2350 articles, 11 RCTs (with a total sample size of 535 subjects) were included in this systematic review. Perioperative intravenous administered MgSO4 could reduce postoperative pain intensity compared with control in 6 trials (55%), but without significant difference in 5 trials (45%). With MgSO4 treatments, postoperative analgesic consumption was significantly reduced in 8 trials (73%), and without significant difference in 2 trials (18%). Two trials evaluated the time to first request of analgesic after surgery and showed prolong of 2.3 hours and 93 minutes respectively. MgSO4 group had less postoperative nausea (relative risk [RR] = 0.32, 95% confidence interval [CI] = 0.12–0.82, number needed to harm [NNH] = 8.8), vomiting (RR = 0.38, 95% CI = 0.15–0.92, NNH = 9.7), and shivering (RR = 0.31, 95% CI = 0.11–0.88, NNH = 5.2).Conclusion:Perioperative intravenous administration of MgSO4 in orthopedic surgery could reduce postoperative analgesic consumption and adverse effects such as vomiting, nausea, and shivering. These trials do not provide convincing evidence of beneficial effects on postoperative pain intensity and the time to first analgesic request. More trials should be conducted for the roles of MgSO4 in pain management for orthopedic surgery. However, intravenous MgSO4 administration should be considered as a strategy to relieve postoperative pain in orthopedic surgery patients.

Magnesium and Pain

“…Magnesium is a critical participant in various physiological processes of the body. Therefore, much attention has focused on anesthesiology [ 23 ], resulting in many clinical trials [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ], reviews, and meta-analyses [ 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. In particular, the pain attenuation effect of magnesium was investigated to improve the outcomes in surgical patients.…”

A prospective randomized controlled trial to study the effect of preoperative and intraoperative magnesium over postoperative ileus and postoperative pain in major non–laparoscopic abdominal surgeries

“…Levaux et al studied 24 patients undergoing major lumbar surgeries. 10 In this study intervention group received 50 mg/kg of intravenous magnesium sulfate this study reveals the bowls dose reduces postoperative analgesic consumption and makes greater satisfaction and better sleep in first 24 hours.…”

“…In another study "Telci et al" studied the administration of magnesium sulfate infusion, reduces intraoperative anaesthetic requirements. 10 81 patients (36 female, 45 male) undergoing effective spinal surgeries were divided into two groups. The intervention group received 30 mg/kg bolus and 10 mg/kg infusion during the operation for maintenance lower consumed doses of propofol, remifentanil and rocuronium were identified when magnesium sulfate was increased the dosage of anaesthetic drugs was reduced but in low doses of 10 mg/kg/hr side effect of magnesium were not developed.…”

Comparative evaluation of epidural bupivacaine alone and bupivacaine combined with magnesium sulfate in providing postoperative analgesia: a meta-analysis of randomized controlled trials

“…The analgesic effect primarily depends on Mg2+ blocks inward current flow through ion channels linked to NMDA receptors [23]. Although a previous systematic review found that intravenous administration of magnesium sulfate in orthopedic surgery could reduce postoperative requirement for postoperative analgesics and adverse events such as vomiting, nausea, and shivering [24], the role of intravenous magnesium sulfate was controversial. Some studies had found that intravenous magnesium failed to improve postoperative pain in gastrointestinal surgery [25] and in a pediatric population undergoing tonsillectomy [26].…”