Lidocaine and Magnesium Sulfate in Anesthesia
New methods for hemodynamic stabilization in anesthesia are constantly being developed. In particular, in light of the opioid epidemic and severe opioid side effects 1, opioid-free or opioid-reduced anesthesia procedures have garnered increasing attention 2. In addition, previous studies have already established the efficacy of lidocaine or magnesium sulfate administered individually as anesthetics 3; they are both safe and efficacious with regard to hemodynamic management in the context of laryngoscopy and intubation. However, given that co-administered anesthetics typically interact synergistically, multimodal approaches have been gaining traction 4. As such, the co-administration of lidocaine and magnesium sulfate has become an increasingly viable and popular option in anesthesia.
A 2008 study first assessed the efficacy of adding magnesium sulfate as an adjuvant to lidocaine for intravenous regional anesthesia in upper limb surgery 5. This study found that the addition of magnesium sulfate hastened the onset of both the sensory and motor block and decreased tourniquet pain. However, they did note a transient increase in pain on injection of the anesthetic if magnesium sulfate was added.
Thereafter, these findings were corroborated by a 2012 study assessing the effect of adding magnesium sulfate to lidocaine in the prevention of acute pain in hand surgery patients under intravenous regional anesthesia 6. To this end, the analgesic effects of magnesium sulfate plus lidocaine, paracetamol plus lidocaine, and placebo plus lidocaine were compared. Results revealed that the group receiving magnesium sulfate plus lidocaine demonstrated the lowest time from drug injection to both motor and sensory block onset, and the longest motor block duration.
More recently, a 2020 study confirmed the synergistic effect of lidocaine and magnesium sulfate on reducing perioperative pain and subsequent opioid consumption following mastectomy 7. Specifically, patients who were administered lidocaine plus magnesium sulfate had lower pain scores within 24 hours postoperatively, as assessed by numerical and verbal rating scales on discharge.
Finally, a 2021 study added further support to these findings, demonstrating that lidocaine with magnesium sulfate preserved hemodynamic stability during general anesthesia without prolonging neuromuscular blockade. Specifically, they gauged the effects of lidocaine and magnesium sulfate, isolated or combined, on hemodynamic parameters and cisatracurium-induced neuromuscular blockade. Magnesium sulfate had no effect on the speed of onset of cisatracurium-induced neuromuscular blockade, but significantly prolonged all neuromuscular blockade recovery features. The addition of lidocaine to magnesium sulfate stabilized hemodynamic parameters such as heart rate and mean arterial pressure, without influencing cisatracurium neuromuscular blockade 8. No adverse events were noted. Limitations of the study include the fact that the actual plasma concentrations of cisatracurium were not measured and the fact that groups were intraoperatively treated with remifentanil, which may have influenced results.
Future research will need to elucidate the mechanisms of these effects and the precise dosage regimen for optimizing patient hemodynamic stability. Given the heterogeneity of clinical study contexts, these studies’ findings lay the foundation for clinical decision-making involving the co-administration of lidocaine and magnesium sulfate for multimodal anesthesia across surgical contexts.
References
1. de Boer, H. D., Detriche, O. & Forget, P. Opioid-related side effects: Postoperative ileus, urinary retention, nausea and vomiting, and shivering. A review of the literature. Best Practice and Research: Clinical Anaesthesiology (2017). doi:10.1016/j.bpa.2017.07.002
2. Bakan, M. et al. Opioid-free total intravenous anesthesia with propofol, dexmedetomidine and lidocaine infusions for laparoscopic cholecystectomy: a prospective, randomized, double-blinded study. Brazilian J. Anesthesiol. (English Ed.) (2015). doi:10.1016/j.bjane.2014.05.001
3. Mendonça, F. T., de Queiroz, L. M. da G. M., Guimarães, C. C. R. & Xavier, A. C. D. Effects of lidocaine and magnesium sulfate in attenuating hemodynamic response to tracheal intubation: single‐center, prospective, double‐blind, randomized study. Brazilian J. Anesthesiol. (2017). doi:10.1016/j.bjan.2016.02.001
4. Hendrickx, J. F. A., Eger, E. I., Sonner, J. M. & Shafer, S. L. Is synergy the rule? a review of anesthetic interactions producing hypnosis and immobility. Anesth. Analg. (2008). doi:10.1213/ane.0b013e31817b859e
5. Narang, S., Dali, J. S., Agarwal, M. & Garg, R. Evaluation of the efficacy of magnesium sulphate as an adjuvant to lignocaine for intravenous regional anaesthesia for upper limb surgery. Anaesth. Intensive Care (2008). doi:10.1177/0310057×0803600614
6. Mirkheshti, A., Aryani, M. R., Shojaei, P. & Dabbagh, A. The effect of adding magnesium sulfate to lidocaine compared with paracetamol in prevention of acute pain in hand surgery patients under intravenous regional anesthesia (IVRA). Int. J. Prev. Med. (2012).
7. Mendonça, F. T. et al. Synergistic effect of the association between lidocaine and magnesium sulfate on peri-operative pain after mastectomy: A randomised, double-blind trial. Eur. J. Anaesthesiol. (2020). doi:10.1097/EJA.0000000000001153
8. Paula-Garcia, W. N., Oliveira-Paula, G. H., de Boer, H. D. & Garcia, L. V. Lidocaine combined with magnesium sulfate preserved hemodynamic stability during general anesthesia without prolonging neuromuscular blockade: a randomized, double-blind, controlled trial. BMC Anesthesiol. 21, 91 (2021).