Impact of intraoperative intravenous magnesium on spine surgery: A systematic review and meta-analysis of randomized controlled trials

Abstract

Background The effectiveness and safety of intraoperative intravenous magnesium (IIM) on spine surgery remain uncertain, as recent randomized controlled trials (RCTs) yielded conflicting results. The purpose of this study was to determine the impact of IIM on spine surgery.Methods A literature search was performed on multiple electronic databases, ClinicalTrial.gov and Google Scholar on July 12th 2021, and reference lists were examined. We selected RCTs comparing the effects of IIM with placebo treatment on spine surgery. We calculated pooled standard mean difference (SMD) or risk ratio (RR) with 95% confident interval (CI) under a random-effect model. We assessed risk of bias using Cochrane risk-of-bias tool and Jadad score was applied to assess the quality of each included trial. Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was used to determine the confidence in effect estimates. Sensitivity analysis was conducted by omitting each included study one by one from the pooled analysis. PROSPERO Registration: CRD42021266170.Findings Fourteen trials of 781 participants were included. Low-to moderate-quality evidence suggested that IIM reduces postoperative morphine consumption at 24 h (SMD: -1¢61 mg, 95% CI: -2¢63 to -0¢58) and intraoperative remifentanil requirement (SMD: -2¢09 ug/h, 95% CI: -3¢38 to -0¢81). High-quality evidence suggested that IIM reduces the risk of postoperative nausea and vomiting compared with placebo (RR: 0¢43, 95% CI: 0¢26 to 0¢71). Besides, moderate-quality evidence suggested that recovery orientation time in the IIM group is longer than control group (SMD: 1¢13 min, 95% CI: 0¢83 to 1¢43).Interpretation IIM as adjuvant analgesics showed overall benefits on spine surgery in terms of reducing analgesic requirement and postoperative nausea and vomiting; however, potential risks of IIM, such as delayed anesthetic awakening, should not be ignored. Future evidence will inform the optimal strategy of IIM administration for patients undergoing spine surgery.

Analgesic Effects of Preoperative Combination of Oral Pregabalin and Intravenous Magnesium Sulfate on Postoperative Pain in Patients Undergoing Posterolateral Spinal Fusion Surgery: A 4-arm, Randomized, Double-blind, Placebo-controlled Trial

“…The analgesic potential of pregabalin or magnesium sulfate used individually in spine surgery has been investigated previously. [14][15][16]18,19,28,29 In a meta-analysis, Jiang et al 16 reported that pregabalin is significantly associated with reduced VAS for pain at rest and decreased cumulative morphine consumption at 24 and 48 hours postoperatively in patients undergoing spine surgery. Regarding the use of magnesium sulfate, a recent meta-analysis and systematic review including 14 clinical trials (781 participants) found a significant association between intraoperative magnesium sulfate infusion and reduction in postoperative morphine consumption in spine procedures.…”

“…16 Magnesium sulfate is another nonopioid drug with efficacy as an analgesic adjuvant in various procedures, including spine surgery. 18,19 The major mechanism of the analgesic effect of magnesium is blockade of the N-methyl-D-aspartate receptor, which in turn inhibits calcium influx and prevents central sensitization. [20][21][22] In addition, there is growing preclinical evidence of an interaction between the α2δ-1 subunit of the calcium channel and the N-methyl-D-aspartate receptor, and of their involvement in neuropathic pain.…”

Development of multidisciplinary, evidenced-based protocol recommendations and implementation strategies for anterior lumbar interbody fusion surgery following a literature review

“…[248,249] A RCT involving elective spine surgery patients demonstrated that intraoperative 50 mg/kg IV MgSO 4 given as a single bolus dose significantly reduced opioid consumption, improved patient discomfort, and reduced the incidence of PONV. [248,249] Intraoperative low-dose ketamine combined with MgSO 4 reduced opioid use and improved pain scores at 48 hours postoperatively in elective spine surgery patients. [250] Ketamine, another NMDA antagonist, reduces the peri- and postoperative opioid analgesic requirement and prolongs the time to first opioid dose.…”

“…Intraoperative IV magnesium sulfate (MgSO 4 ) acts as a noncompetitive antagonist of the NMDA receptor, which makes it a useful adjuvant for perioperative analgesia in patients undergoing spine surgery. [248,249] A RCT involving elective spine surgery patients demonstrated that intraoperative 50 mg/kg IV MgSO 4 given as a single bolus dose significantly reduced opioid consumption, improved patient discomfort, and reduced the incidence of PONV. [248,249] Intraoperative low-dose ketamine combined with MgSO 4 reduced opioid use and improved pain scores at 48 hours postoperatively in elective spine surgery patients.…”

Postoperative analgesia for complex spinal surgery

“…A recent systematic review and meta-analysis of RCTs on the use of intra-operative i.v. magnesium in spine surgery showed low- to moderate quality evidence that it reduces intra-operative remifentanil requirements and morphine requirement at 24 h. With regard to adverse events, there was less PONV but longer recovery orientation times [29 ▪ ]. An RCT showed significantly lower cumulative morphine requirement at 48 h postoperatively and lower pain scores in the magnesium group compared with control [30 ▪ ].…”