Effect of Magnesium on General Anesthesia in Children

The Benefits of Magnesium

Magnesium is a natural cation that helps with many essential biological functions, including energy metabolism, proper muscle contraction, regulating the flow of ions in and out of cells, keeping neurons working properly, and helping regulate calcium levels in the body.

Aside from these functions, studies have shown that magnesium also has equally important anti-nociceptive properties that can reduce the demand for anesthetic drugs like propofol, remifentanil, and vecuronium during total intravenous anesthesia. Moreover, magnesium administration has shortened the time needed to reach a bi-spectral (BIS) index value of 60. Although some authors may not accept the BIS index as the best way to measure how deeply someone is sedated, it is the most accepted way to measure sedation and anesthesia in children. Previous studies have looked at how magnesium affects the amount of anesthetic needed to keep bi-spectral index values within a specific range.

This present study evaluated the influence of intraoperative magnesium on BIS values while we kept other anesthetic variables unchanged during pediatric anesthesia.

The Study Method on Magnesium for Bi-Spectral Index Values during Pediatric Anesthesia

80 pediatric patients with American Society of Anesthesiologists (ASA) physical status I (normal healthy patient), ages 2 to 8 years, and scheduled for minor infra-umbilical elective procedures participated in this prospective controlled study. They were randomly and equally allocated into two groups — Group I received magnesium sulfate, while control Group II received an acetate ringer solution. The anesthetist gave the patients a premedication of intramuscular midazolam and atropine thirty minutes before induction of anesthesia by inhalation of sevoflurane. All patients received a caudal epidural block of bupivacaine and paracetamol suppository for intraoperative analgesia.

We compared the groups regarding 1) BIS values, 2) Hemodynamic parameters, 3) Arterial oxygen saturation, 4) End-tidal carbon dioxide, 5) Respiratory rate, and 6) Tidal volume.

The Results

The magnesium group (Group I) showed significantly lower BIS values and a shorter time of 20 minutes to reach BIS values below 60. Tidal volume and respiratory rate, both respiratory parameters, were significantly lower in the magnesium group. No significant differences between the two groups were detected.

The Conclusion

Magnesium produced significantly lower BIS values, less time to reach BIS values below 60, lower tidal volume, and lower respiratory rate during pediatric general anesthesia.

Reference

Effect of Magnesium Sulfate on Bi-Spectral Index (BIS) Values During General Anesthesia in Children