Intravenous Magnesium Sulfate for Multimodal Analgesia

Abstract

Purpose Statement

Magnesium Sulfate has been used as a multimodal approach for analgesia as it may reduce opioid consumption in the first 24 hours after surgery and decrease post-operative pain scores.

Introduction

The use of intraoperative opioids for analgesia is associated with postoperative side effects such as respiratory depression, ileus, nausea, and vomiting. The side effects from opioids can prolong hospital stay and cause patient dissatisfaction. Magnesium acts as a N-methyl-D-aspartate (NMDA) receptor antagonist resulting in an analgesic effect, which can be used as an alternative or adjunct to opioids for pain control.

Literature Review

Magnesium sulfate may be beneficial for multimodal pain management as it reduces opioid requirements and postoperative pain. Targeting various receptors in the pain pathway can optimize analgesia and reduce side effects. Magnesium antagonizes the NMDA receptor and blocks calcium channels to modulate pain and inflammatory responses. Perioperative magnesium administration should be considered as a strategy to reduce postoperative pain in patients undergoing surgical procedures.

Description of the Case

A 67-year-old female presented for a bilateral breast revision, bilateral blepharoplasty of upper lids, neck rhytidectomy, and fat graft injection surgery. The patient had a history of postoperative nausea and vomiting. During the maintenance phase of anesthesia, fentanyl 50 mcg was given as needed for signs of pain, rocuronium was re-dosed to maintain paralysis, and ephedrine and phenylephrine were administered to maintain blood pressure. Intravenous magnesium sulfate 2 g was administered as a multimodal approach to analgesia to decrease post-operative opioid consumption and to prevent post-operative nausea and vomiting. The following day the patient tolerated a regular diet, pain was well controlled, and was hemodynamically stable. The patient was discharged home without complications.

Discussion and Conclusion

Magnesium sulfate may be beneficial for multimodal pain management as it reduces opioid requirements and postoperative pain. Magnesium antagonizes the NMDA receptor and blocks calcium channels to modulate pain and inflammatory responses. It is unclear which mode of magnesium administration provides an advantage to the analgesic effects. The differences in age and gender-related responses to magnesium for analgesia is undetermined. Further research is necessary to examine the use of intravenous magnesium sulfate for postoperative pain in different patient populations, safe and effective dosing ranges, and the effects of analgesia in various surgeries. Intravenous magnesium sulfate should be considered in multimodal analgesic treatment as an adjunct for postoperative analgesia.