The Effect of Magnesium Sulfate on Motor and Somatosensory Evoked Potentials in Children Undergoing Scoliosis Surgery

Scoliosis Clinical Trial

Official title:

The Effect of Magnesium Sulfate on Motor and Somatosensory Evoked Potentials in Children Undergoing Scoliosis Surgery

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01148888
• Other study ID #: 1000014574
• Status: Completed
• Phase: Phase 2
• First received: June 21, 2010
• Last updated: November 18, 2014
• Start date: June 2010
• Est. completion date: December 2012

Study information

• Verified date: November 2014
• Source: The Hospital for Sick Children
• Contact: n/a
• Is FDA regulated: No
• Health authority: Canada: Health Canada
• Study type: Interventional

Clinical Trial Summary

The primary objective of this study is to determine whether magnesium sulfate has a clinically important effect on the amplitude and latency of somatosensory and motor evoked potentials in patients undergoing surgical correction of idiopathic scoliosis.

Description:

Motor and somatosensory evoked potentials are continuously monitored in the setting of scoliosis surgery to evaluate the integrity of spinal cord pathways. Detection of neural irritation or injury using motor or somatosensory evoked potentials allows the surgeon to modify technique to reverse the insult and proceed without spinal cord compromise. To facilitate evoked potential monitoring, anesthetic agents that attenuate the evoked responses must be avoided.Several different agents have been studied to try to diminish the acute opioid tolerance and/or hyperalgesia seen with remifentanil.

Two studies investigated the effect of magnesium sulfate on intraoperative remifentanil-induced hyperalgesia. In both studies, post-operative pain scores and opioid consumption were decreased in those patients who received magnesium.

Our aim is to establish that magnesium sulfate does not adversely affect somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) in patients undergoing correction of idiopathic scoliosis. Future clinical trials can then be performed investigating the effect of magnesium sulfate on remifentanil-induced hyperalgesia in the same population.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 5
• Est. completion date: December 2012
• Est. primary completion date: June 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 12 Years to 18 Years

Eligibility

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) status I or II

• Adolescent children aged 12 to 18 years undergoing surgery for idiopathic scoliosis

Exclusion Criteria:

• Magnesium use within the last two weeks, either intravenous or oral supplements

• Patients with known electrolyte imbalances or conduction disorders. (Sodium <135 or >143 mmol/L OR Potassium < 3.7 or > 5.0 mmol/L if 12 to 15 yrs; Potassium <3.7 or >4.8 mmol/L if 16 to 18 yrs)

• Renal, cardiac or neuromuscular disorders.(Urea < 2.9 or > 7.1 mmol/L OR Creatinine >79 µmol/L if < 13 yrs; Creatinine > 98 µmol/L if >= 14 yrs)

Study Design

Allocation: Non-Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Crossover Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Scoliosis

Intervention

Drug:
• Magnesium
Magnesium will be administered intravenously at a dose of 50 mg/kg bolus followed by an infusion of 10 mg/kg/hr.

Locations

Country	Name	City	State
Canada	The Hospital for Sick Children	Toronto	Ontario

Sponsors (1)

Lead Sponsor	Collaborator
The Hospital for Sick Children

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Somatosensory and motor evoked potentials	Cortical SEPs will be measured from Cz-Fpz or Ci-Cc (10-20 system of head measurement) and the amplitudes will be taken from the first positive deflection to first negative deflection (P1-N1) after supramaximal stimulation of the posterior tibial nerves at the medial malleolus. The MEP peak-to-peak amplitudes will be measured from left and right tibialis anterior and abductor hallucis muscles. Stimulation parameters will be varied in order to achieve the maximum amplitude values. Evoked potentials will be measured before and at 10 and 30 minutes after the start of the magnesium infusion.	Baseline	No
Primary	Somatosensory and motor evoked potentials	Cortical SEPs will be measured from Cz-Fpz or Ci-Cc (10-20 system of head measurement) and the amplitudes will be taken from the first positive deflection to first negative deflection (P1-N1) after supramaximal stimulation of the posterior tibial nerves at the medial malleolus. The MEP peak-to-peak amplitudes will be measured from left and right tibialis anterior and abductor hallucis muscles. Stimulation parameters will be varied in order to achieve the maximum amplitude values. Evoked potentials will be measured before and at 10 and 30 minutes after the start of the magnesium infusion.	10 and 30 minutes after the start of the magnesium infusion	No