Magnesium as an adjunct in regional anesthesia: literature review

Neringa Umaraitė1, Audronė Grigaliūnaitė2, Ramūnas Tamošiūnas2

1Lithuanian University of Health Sciences, Academy of Medicine, Faculty of Medicine, Kaunas, Lithuania

2Hospital of Lithuanian University of Health Sciences Kaunas Clinics, Department of Anesthesiology, Kaunas, Lithuania


Background. High-quality regional anesthesia should ensure good operating conditions and effective, long-lasting analgesia after surgery. Ways to prolong analgesia in order to allow early patient mobility and rehabilitation procedures are constantly being sought. Magnesium sulfate (MgSO4) as an adjunct to local anesthetics solutions is an attractive option and is being extensively studied.

The aim: to review the scientific literature on usage of MgSO4 as an adjunct in regional anesthesia and to provide clinical conclusions for the application of MgSO4 in this anesthesia.

Methods: The search of the scientific literature was performed in PubMed, Google Scholar online databases, using the following keywords and their combinations: ,,magnesium“, ,,peripheral nerve block“, ,,brachial plexus block“, ,,TAP block”, ,,spinal anesthesia“, ,,epidural anesthesia“, ,,neuraxial anesthesia“. 19 publications were included. Descriptive analysis was used to analyze the literature.

Results. Regardless of type of regional anesthesia, magnesium combined with a local anesthetic shortens the duration of analgesic onset, prolongs both sensory and motor block durations, alleviates postoperative pain. Furthermore, less analgesics are consumed during surgery and postoperative period. Also, magnesium has advantage over some adjuvants to complement the action of local anesthetics or to avoid certain adverse effects. However, there is no consensus on what concentrations and volumes of MgSO4 solution should be used for different types of regional anesthesia.

Conclusions. MgSO4, when used as an adjunct in regional anesthesia, enhances the action of local anesthetics without increasing the frequency of adverse effects.

Keywords: magnesium sulfate, regional anesthesia, peripheral blocks, neuraxial anesthesia.

Full article