Effects of adjunct intrathecal magnesium sulfate to bupivacaine for spinal anesthesia: a randomized, double-blind trial in patients undergoing lower extremity surgery

Abstract

In patients undergoing lower extremity surgery with spinal anesthesia, the addition of 100 mg IT MgSO(4) to 15 mg bupivacaine without opioid supplement, prolonged the duration of the sensory block, decreased postoperative analgesic consumption, and significantly prolonged the onset of spinal anesthesia.

Effects of adding Magnesium Sulphate to Ropivacaine and Fentanyl for spinal anaesthesia

“…The incidence of adverse events (hypotension, pruritis) were insignificant with intrathecal magnesium. This was consistent with the results of other studies (20,21,22,23) Mitrajabalameli and Seyed Hamid Pakzadmoghadam et al compared effects of adding different doses of intrathecal magnesium sulfate for spinal anesthesia in the cesarean section and showed that all doses studied provide safe and effective anesthesia, but 75 mg of this drug increases duration of postoperative analgesia and prolong than sensory and motor block without significant increase in maternal and neonatal side effects (20).…”

“…Magnesium exerts its analgesic action as a non-competitive NMDA receptor antagonist, blocking ion channels in a voltage dependent manner (20,21,22) .This drug is both analgesic and anti -nociceptive additive drug. When used with local anaesthetic, it resulted in prolongation of analgesia without significant complication (23,24).This prolongation of anaesthesia is consistent with the experimental synergistic action between spinal local aneasthetic and NMDA antagonists like magnesium sulphate, which use anti -nociceptive effects via different mechanisms; (25,26,27) hence the rationale for combining the two.…”

“…They provide faster onset and prolonged duration analgesia (16,17,18) .Intrathecal opiods can cause pruritis, urinary retention, respiratory depression, nausea and vomiting as adverse effects. Thus addition of intrathecal magnesium sulphate has been used to study the effect of potentiation of opiods at lower doses on local anaesthetics (20,21,22). Anti-nociceptive effect of Magnesium appears to be relavant not only for chronic pain, but also in postoperative pain based on regulation of calcium influx into the cell.…”

Comparison of two different doses of magnesium sulphate for spinal anaesthesia: a prospective, randomized double-blind study

“…[17][18][19][20] In two studies 17,18 addition of different doses of intrathecal magnesium sulphate to hyperbaric bupivacaine was studied where as in a study 19 fentanyl was also used as adjuvant. Magnesium sulphate 100 mg as adjuvant to bupivacaine and saline was compared in another study.…”

Evaluation of the Effect of Magnesium Sulphate vs. Clonidine as an Adjuvant to Epidural Levobupivacaine in Patients Undergoing Lower Abdominal Surgeries- A Prospective,randomised and Double-Blinded Study

“…In a study conducted by Khalili G and Janghorbini et al, 15 who compared Magnesium Sulphate with Bupivacaine Vs. plain Bupivacaine for lower extremity surgeries concluded that the duration of sensory blockade was significantly longer with Magnesium Sulphate group than in control group (magnesium sulphate 106.5 min. vs. control group 85.5 min., p<0.001), similar to our study.…”