Blood Pressure and Brain Blood Flow Regulation After Midodrine Administration in Those With Spinal Cord Injury

Neural and Mechanical Baroreflex Sensitivity and Cerebral Blood Flow

This project aims to evaluate the physiological effects of Midodrine administration during orthostatic challenge in those with high level spinal cord injury. Midodrine has been shown to improve orthostatic symptoms in those with spinal cord injury but the physiological mechanisms influenced have not been identified. The investigators will examine key physiological components influencing orthostatic tolerance. The investigators will do this, by measuring the baroreflex, and brain blood flow autoregulation (the ability to maintain brain blood flow) before during and after the sit-up test. Two sit-up tests will occur; one before Midodrine administration, and one after administration of a 10mg dose of Midodrine.

Study Overview

• Status: Completed
• Conditions: Orthostatic Intolerance
• Intervention / Treatment: Drug: Midodrine

• Study Type: Observational
• Enrollment (Actual): 22

Contacts and Locations

Study Locations

• Canada
  • British Columbia
    • Vancouver, British Columbia, Canada, V5Z 2G9
      • GF Strong Hospital and Rehabilitation Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 49 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Individuals with spinal cord injury currently in primary care (less than one year post injury)

Description

Inclusion Criteria:

• To be included in the study, participants must have sustained a traumatic spinal cord injury within the ages of 18-49 years.
• Also, participants must have an injury level above the 6th thoracic vertebrae and be a non-smoker for a minimum of one year.

Exclusion Criteria:

• Any participants with a history of cardiovascular disease, pulmonary disease or diabetes mellitus will not be eligible.
• Also, participants will not be eligible to take part in study if they experiences acute distress, or are taking medications known to influence cardiovascular function.
• Patient will be not eligible for the study if he/she has known adverse reaction to Midodrine.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Baroreflex sensitivity	Immediately after drug administration (30 mins)

Secondary Outcome Measures

Outcome Measure	Time Frame
Cerebral autoregulation	Thirty minutes after administration

Collaborators and Investigators

• Sponsor: University of British Columbia
• Investigators: Principal Investigator: Darren Warburton, PhD, University of British Columbia; Principal Investigator: Andrei Krassioukov, MD PhD, GF Strong Hospital University of British Columbia

Study record dates

Study Major Dates

• Study Start: March 1, 2012
• Primary Completion (Actual): November 1, 2013
• Study Completion (Actual): November 1, 2013

Study Registration Dates

• First Submitted: December 21, 2011
• First Submitted That Met QC Criteria: December 22, 2011
• First Posted (Estimate): December 23, 2011

Study Record Updates

• Last Update Posted (Actual): October 1, 2019
• Last Update Submitted That Met QC Criteria: September 27, 2019
• Last Verified: September 1, 2019

More Information

Terms related to this study

• Keywords: Orthostatic intolerance in people with spinal cord injury
• Additional Relevant MeSH Terms: Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Wounds and Injuries; Trauma, Nervous System; Spinal Cord Diseases; Autonomic Nervous System Diseases; Primary Dysautonomias; Spinal Cord Injuries; Orthostatic Intolerance; Physiological Effects of Drugs; Adrenergic Agents; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Autonomic Agents; Peripheral Nervous System Agents; Adrenergic alpha-Agonists; Adrenergic Agonists; Sympathomimetics; Vasoconstrictor Agents; Adrenergic alpha-1 Receptor Agonists; Midodrine
• Other Study ID Numbers: H11-02823