AzTrials
AzTrials

Intraoperative Neurophysiological MonitoringPhase 4NCT04938765

Effect of Magnesium Sulfate Bolus on Intraoperative Neuromonitoring

A Phase 4 study testing Magnesium sulfate and Normal Saline in people with Intraoperative Neurophysiological Monitoring and Magnesium Sulfate, run by Loma Linda University at 1 site in United States.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
Search all trials

Trial summary

Magnesium Sulfate(MgSo4) is increasingly being used as part of the multimodal pain regimen in the perioperative period. The intraoperative neurophysiological monitoring (IONM) is utilized in complex spine and cranial surgeries to assess the functional integrity of the neural pathways. Read more about this study

Who is it for?
Ages 18 to 80 years
What is being tested?
Magnesium sulfate and Normal Saline
Type of treatment
Injection or infusion
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
50 participants
Where
1 siteUnited States
Study dates
18 Mar 2022to Mar 2027
Phase
Phase 4
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 80 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Patients aged 18 to 80 years
  • Belonging to American Society of Anesthesiologists physical status (ASA) I, II
  • Undergoing elective spine or cranial surgery where intraoperative neuromonitoring including short latency somatosensory evoked potentials (SSEP or SEP) and transcranial electrical muscle motor evoked potentials recording from muscles (TceMEP or TcMEP or mMEP or MEP) is planned.

Who cannot join

  • Magnesium use within the last 2 days, either intravenous or oral supplements.
  • Patients with known electrolyte imbalances (Sodium <135 or >145 mmol/L OR Potassium < 3.5 or > 5.0 mmol/L, Magnesium >1.2 mmol/L.
  • Severe cardiac or cardiac conduction disorders.
  • Severe pulmonary disease.
  • Patients with significant neuromuscular disorders or preexisting motor or sensory deficits other than focal upper limb neuropathy or focal cervical radiculopathy or mild cervical myelopathy.
  • Severe Renal disease - serum creatinine of > 2 mg/dl.
  • Pregnant or breastfeeding patients.
  • Unable to obtain adequate baseline SSEPs and MEPs.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Rashmi Vandse, MD contact

9095584000

rvandse@llu.edu

United States1 site, 1 recruiting
  • Loma linda University Medical Center

    Loma Linda, California, 92354

    Rashmi Vandse, MD, 909-558-4000 ext. 88054, rvandse@llu.edu

    Penelope Garcia, 909.558.5966, pegarcia@llu.edu

    Recruiting

Other trials in United States

About this study

Official title: Randomized and Placebo Controlled Study to Evaluate the Effect of Magnesium Sulfate on Intraoperative Neuromonitoring.

Magnesium Sulfate(MgSo4) is increasingly being used as part of the multimodal pain regimen in the perioperative period. The intraoperative neurophysiological monitoring (IONM) is utilized in complex spine and cranial surgeries to assess the functional integrity of the neural pathways. The effect of Magnesium sulfate on IONM has not been studied.

This is a prospective, double blind, randomized placebo controlled trial to study the effect of Magnesium sulfate bolus on the amplitude and latency of somatosensory(SSEPs) and motor evoked potentials(MEPs) in patients undergoing surgery requiring IONM.

Read the detailed description

The primary objective of this study is to investigate the effect of magnesium sulfate on the amplitude of the SSEP with tibial nerve stimulation. Secondary objectives are to study the effect of magnesium sulfate on the latency of SSEPs and the amplitude of MEPs in patients undergoing spine and/or cranial surgery requiring intraoperative neuromonitoring.

Background: Magnesium Sulfate is increasingly being used as part of the multimodal pain regimen in the perioperative period. The efficacy of intravenous (IV) magnesium sulfate in reducing the postoperative pain scores and/or postoperative opioid use has been established in several randomized controlled trials, systematic reviews, and meta-analyses. The multimodal intraoperative neurophysiological monitoring (IONM) is increasingly being utilized in complex spine surgeries to assess the functional integrity of the neural pathways. The goal of IONM is to avert permanent damage by proving real-time feedback from sensory tracts, motor tracts, and individual nerve roots thus alerting any impending injury which allows for modification of management in time.

Several factors like, hypoxia, hypercarbia, changes in blood pressure and temperature can affect the IONM in addition to direct surgical injury to neural structures. In addition, several drugs including anesthetic agents can have a significant effect on IONM. Hence anesthetic regimen is usually tailored to facilitate IONM during these surgeries. The infusion of propofol and remifentanil are commonly used for maintenance of anesthesia during these procedures. Opioid analgesics play a central role in the anesthetic cocktail as the pain associated with complex spinal surgery can be debilitating. However, opioids can also complicate the postoperative pain management by inducing opioid induced hyperalgesia and /or tolerance. The current trend is to implement a multimodal analgesic approach to achieve an additive or synergistic analgesic effect by targeting different receptors in the peripheral and central pain signaling pathways while minimizing opioid-related adverse effects. Magnesium sulfate has shown promising results when used as part of the multimodal pain management in previous studies in addition it can also has shown to attenuate the remifentanil-induced hyperalgesia which is commonly used as part of the anesthetic regimen. However, the effect of Magnesium Sulfate on intraoperative neuromonitoring is not been studied.

Methods Procedures involved (Research Interventions):

After obtaining the written informed consent and premedication, patients will be taken to the operating room. The standard ASA monitors will be applied. They will be monitored with electrocardiography, noninvasive and/or invasive blood pressure (BP), pulse oximetry, and temperature monitor along with brain function monitor to monitor the depth of anesthesia (Sedline monitor) during surgery.

After preoxygenation, the patient will be induced with general anesthesia using fentanyl 1-3 mg/kg or Remifentanil 1-3 mcg/kg, lidocaine 1-2 mg/kg, Propofol 1-3 mg/kg, and succinylcholine 1-2 mg/kg or Rocuronium 0.3-0.5 mg/kg. Inhalation anesthetic agents will not be used for induction or maintenance of anesthesia but may be used after the end of data collection for this study and/or during closing. Anesthetic infusion consisting of propofol 50-150 mg/kg, remifentanil 0.05-0.2 mg/kg will be started immediately after the induction for maintenance of general anesthesia and doses may be adjusted to higher amounts if needed. The BP will be maintained within 20% of patient's baseline using phenylephrine infusion or other appropriate vasoactive agents after the induction of anesthesia. End-tidal carbon dioxide will be maintained within normal limits. Patients will be actively warmed using a Bair Hugger™ or similar device(s) ("warmer(s)") to prevent any hypothermia.

In patients given rocuronium, neuromuscular blockage will be reversed before obtaining the baseline IONM recordings. The baseline set of SSEPs and MEPs will be recorded before the study drug administration and consisting of 2 to 4 measurements; T0 represents the average of these measurements. For study group, MgSo4 diluted to < 20% concentration in 20 ml normal saline will be administered as 40 mg/kg bolus dosed to ideal body weight over 10 min. For control group, 20 ml of normal saline bolus will be administered over 10 mins. Magnesium group will also be given continuous infusion of MgSO4 at 10mg/kg/hr. till the end of the surgery. Repeat SSEPs and MEPs will be recorded at the end of the bolus ("0" minutes) (T1) as well as 10 (T2) and 30 (T3) minutes following the completion of the bolus dose.

Patient's hemodynamic data also will be collected at baseline and every 5 mins up to 30 mins following the administration of the drug.

The T1,T2,T3 data will be compared with the To(baseline) data to evaluate the effect of MgSO4 on intraoperative neuromonitoring.

Being tested
Magnesium sulfate, Normal Saline
Keywords
multimodal analgesia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Magnesium sulfateDrug

    Effect of 40mg/kg Magnesium sulfate bolus dosed to ideal body weight on intraoperative neuromonitoring

  • Normal SalineDrug

    20 ml of normal saline bolus will be administered to the control group over 10 mins.

Study groups in NCT04938765
Study groupRoleWhat they receive
Magnesium sulfate armExperimentalMgSo4 diluted to 20% will be administered at 40 mg/kg dosed to ideal body weight over 10min to the study arm followed by 10mg/kg/hr infusion.
Receives: Drug: Magnesium sulfate
Normal SalinePlacebo comparator20 ml of normal saline bolus will be administered to the control group over 10 mins.
Receives: Drug: Normal Saline

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Change in the amplitude of SSEPs.

    Baseline SSEP recording is done before the administration of MgSo4 or placebo and will be compared with the SSEPs measured at 0,10 and 30 minutes following the end of the bolus dose of MgSO4 or normal saline. Any change in the amplitude will be analyzed. For SSEPs, 50% reduction in amplitude will be considered as significant change.

    Measured: Up to 30 minutes after the end of bolus dose of MgSO4 or Normal saline.

Secondary outcomes (2)
  1. Change in the latency of SSEP compared to baseline.

    Baseline SSEP recording is done before the administration of MgSo4 or placebo and will be compared with the SSEPs measured at 0, 10 and 30 minutes following the end of the bolus dose of MgSO4 or normal saline.10% increase in latency will be considered as significant change.

    Measured: Up to 30 minutes after the end of bolus dose of MgSO4 or Normal saline.

  2. Change in the amplitude of MEPs.

    Baseline MEP recording is done before the administration of MgSo4 or placebo and will be compared with the MEPs measured at 0, 10 and 30 minutes following the end of the bolus dose of MgSO4 or normal saline. Any change in the amplitude of MEPs will be analyzed .For MEPs, 75% decrease in amplitude is considered as significant change

    Measured: Up to 30 minutes after the end of bolus dose of MgSO4 or Normal saline.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted24 Jun 2021
  2. Study start18 Mar 2022
  3. Primary completionMar 2027 (estimated)
  4. Study completionMar 2027 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 4
Primary purpose
Diagnosis
Allocation
Randomised
Intervention model
Parallel groups
Model description
Prospective double blind randomized clinical trial
Masking
Double blind
Who is masked
Participant, Outcomes assessor
Enrolment
50 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04938765
Sponsor's protocol ID
5210244
Status last verified
Apr 2026
First submitted
16 Jun 2021
Last updated
24 Apr 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
No

Publications

  • Albrecht E, Kirkham KR, Liu SS, Brull R. Peri-operative intravenous administration of magnesium sulphate and postoperative pain: a meta-analysis. Anaesthesia. 2013 Jan;68(1):79-90. doi: 10.1111/j.1365-2044.2012.07335.x. Epub 2012 Nov 1.

    PubMed 23121612
  • De Oliveira GS Jr, Castro-Alves LJ, Khan JH, McCarthy RJ. Perioperative systemic magnesium to minimize postoperative pain: a meta-analysis of randomized controlled trials. Anesthesiology. 2013 Jul;119(1):178-90. doi: 10.1097/ALN.0b013e318297630d.

    PubMed 23669270
  • Guo BL, Lin Y, Hu W, Zhen CX, Bao-Cheng Z, Wu HH, Kaye AD, Duan JH, Qu Y. Effects of Systemic Magnesium on Post-operative Analgesia: Is the Current Evidence Strong Enough? Pain Physician. 2015 Sep-Oct;18(5):405-18.

    PubMed 26431120
  • Arumugam, S. , S. M. Lau, C. and Chamberlain, R. (2016) Perioperative Adjunct Magnesium Decreases Postoperative Opioid Requirements-A Meta-Analysis. International Journal of Clinical Medicine, 7, 297-308. doi: 10.4236/ijcm.2016.75032.

  • Dehkordy ME, Tavanaei R, Younesi E, Khorasanizade S, Farsani HA, Oraee-Yazdani S. Effects of perioperative magnesium sulfate infusion on intraoperative blood loss and postoperative analgesia in patients undergoing posterior lumbar spinal fusion surgery: A randomized controlled trial. Clin Neurol Neurosurg. 2020 Sep;196:105983. doi: 10.1016/j.clineuro.2020.105983. Epub 2020 Jun 2.

    PubMed 32521394
  • Kizilcik N, Koner O. Magnesium Sulfate Reduced Opioid Consumption in Obese Patients Undergoing Sleeve Gastrectomy: a Prospective, Randomized Clinical Trial. Obes Surg. 2018 Sep;28(9):2783-2788. doi: 10.1007/s11695-018-3243-7.

    PubMed 29754384
  • Shin HJ, Kim EY, Na HS, Kim TK, Kim MH, Do SH. Magnesium sulphate attenuates acute postoperative pain and increased pain intensity after surgical injury in staged bilateral total knee arthroplasty: a randomized, double-blinded, placebo-controlled trial. Br J Anaesth. 2016 Oct;117(4):497-503. doi: 10.1093/bja/aew227. Epub 2016 Oct 17.

    PubMed 28077538
  • Ballesteros-Flores CG, Garrido-Aguirre E, Carrillo-Esper R, et al. Hypomagnesemia in the perioperative period. Current concepts. Rev Mex Anest. 2013;36(2):114-118.

  • Whittaker JD, Downes F, Becker H, Garnham A, Wall M. Influence of Perioperative Serum Magnesium for Cardiac and Noncardiac Morbidity and Mortality Following Emergency Peripheral Vascular Surgery. J Cardiothorac Vasc Anesth. 2019 Feb;33(2):474-479. doi: 10.1053/j.jvca.2018.05.042. Epub 2018 May 28.

    PubMed 30045811
  • Herroeder S, Schonherr ME, De Hert SG, Hollmann MW. Magnesium--essentials for anesthesiologists. Anesthesiology. 2011 Apr;114(4):971-93. doi: 10.1097/ALN.0b013e318210483d.

    PubMed 21364460
  • Hicks MA, Tyagi A. Magnesium Sulfate. [Updated 2020 May 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK554553/

  • Okusanya BO, Oladapo OT, Long Q, Lumbiganon P, Carroli G, Qureshi Z, Duley L, Souza JP, Gulmezoglu AM. Clinical pharmacokinetic properties of magnesium sulphate in women with pre-eclampsia and eclampsia. BJOG. 2016 Feb;123(3):356-66. doi: 10.1111/1471-0528.13753. Epub 2015 Nov 24.

    PubMed 26599617
  • Yanni DS, Ulkatan S, Deletis V, Barrenechea IJ, Sen C, Perin NI. Utility of neurophysiological monitoring using dorsal column mapping in intramedullary spinal cord surgery. J Neurosurg Spine. 2010 Jun;12(6):623-8. doi: 10.3171/2010.1.SPINE09112.

    PubMed 20515347
  • Huang ZF, Chen L, Yang JF, Deng YL, Sui WY, Yang JL. Multimodality Intraoperative Neuromonitoring in Severe Thoracic Deformity Posterior Vertebral Column Resection Correction. World Neurosurg. 2019 Jul;127:e416-e426. doi: 10.1016/j.wneu.2019.03.140. Epub 2019 Apr 11.

    PubMed 30981802
  • Minahan RE. Intraoperative neuromonitoring. Neurologist. 2002 Jul;8(4):209-26. doi: 10.1097/00127893-200207000-00001.

    PubMed 12803681

Questions about this trial

What is this clinical trial studying?

A Phase 4 study testing Magnesium sulfate and Normal Saline in people with Intraoperative Neurophysiological Monitoring and Magnesium Sulfate, run by Loma Linda University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 24 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Rashmi Vandse, MD (9095584000, rvandse@llu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change in the amplitude of SSEPs. (time frame: Up to 30 minutes after the end of bolus dose of MgSO4 or Normal saline.). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04938765, which also lists 19 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Apr 2026.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in