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CompletedNCT00175773Updated Oct 1, 2019

Mechanisms of Orthostatic Intolerance in Spinal Cord Injured Individuals and Following Bed Rest

An observational study in Spinal Cord Injury, sponsored by University of British Columbia. Completed at 1 site in Canada. Open to participants aged 19 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2019-10-01.

Sponsored by University of British Columbia · Observational

Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
51
Ages
19 Years to 55 Years
Sex
All
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Study summary

The primary purpose of this study is to investigate the relationship between the extent of neurologic (nerve) impairment in patients with spinal cord injuries and how well the nerves passing down the spine to the heart and blood vessels are working. These nerves are called the descending spinal sympathetic pathway (DSSP) and are important in controlling many functions, including blood pressure. We also wish to examine how injury severity and DSSP function influence blood levels of nor-epinephrine and epinephrine. Nor-epinephrine and epinephrine are hormones released into the blood that are also important in controlling blood pressure. Thus, we will also look at how the effect of the extent of DSSP dysfunction influences heart rate and blood pressure and blood levels of certain enzymes.

Read the detailed description

Subjects Healthy able-bodied control volunteers, individuals with acute and chronic spinal cord injury, and individuals who have undergone a period of bed rest.

ASIA and SSR Assessment. The severity of injury to the motor and sensory spinal pathways will be documented in accordance to the American Spinal Injury Association (ASIA). The sympathetic skin response (SSR) will be examined in order to determine the completeness of injury to the DSSP. SSRs will be recorded in subjects in supine position, with the room temperature between 21-25oC. Subjects will rest supine for at least 30 min before the beginning of the examination. The procedure will take approximately 20-30 min. Self-adhesive electrodes will be applied to the hands and feet of the patient. SSRs will be recorded bilaterally and simultaneously from both hands and feet over 5 s and sampled at a band pass of 3Hz to 3 kHz. The median nerve will be stimulated (0.2ms duration, 10-20mA intensity) and 5-10 SSRs samples will be recorded. The latency and amplitude of SSRs will be measured and compared in each case.

"Sit up test". We will use a sit-up test to evaluate blood pressure control and orthostatic tolerance. Before the test the subject will lie down on a tilt table, in a temperature controlled environment for a period of 10 min. Then the subject will be passively seated to 90° and will keep this position without moving for 20 minutes. The test will be aborted if subjects become lightheaded or symptomatic. All individuals with SCI will be assessed for the continuity of the DSSP. Continuous non-invasive BP (Finometer, FMS, Arnhem, The Netherlands) and ECG (lead II, 3 electrodes on the thorax), monitoring will be performed pre-test, during and post-test. In all subjects the following measurements are planned: recordings of BP and ECG during 10 min in supine and 20 min in sitting position. Two blood samples will be collected prior to the sit-up test after 30 min of rest in supine position and 3-5 min after sit-up test. Serum level catecholamines will be examined. Butterfly catheters will be inserted at least 30 min prior to the sit-up test. This will allow the collection of blood without additional stress to the participant and activation of catecholamines release by venopuncture. Two blood samples will be drawn to determine the serum levels of NE and E from the antecubital vein of each individual before and immediately after the orthostatic challenge.

Circadian rhythm and 24hr Holter monitoring of ECG. We will obtain continuous HR recordings and following analysis will determine the beat-to-beat HRV during the 24 hr period. The subject will wear a portable unit connected with electrodes on the chest-wall. During the day the subject can do normal daily activities. We will analyze at least 3 measurement points (10 min interval) during the day and night periods in each individual. HRV analysis will occur off-line: briefly, we will use an autoregressive model for the frequency domain variables of HRV: low-frequency power (LF, 0.04-0.15 Hz), and high-frequency power (HF, 0.15-0.4 Hz). LF power is believed to represent sympathetic tone while HF power represents parasympathetic tone.

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Conditions studied

  • Spinal Cord Injury

Keywords

  • Orthostatic stress
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In context

Spinal Cord Injuries

1,948 studies on the registry are indexed under Spinal Cord Injuries; 505 are open to participants now.

This study's enrollment of 51 is below the median of 60 across 323 observational studies indexed under Spinal Cord Injuries.

Browse Spinal Cord Injuries studies →

Lead sponsor

University of British Columbia is the lead sponsor of 1,310 studies on the registry; 253 are open to participants now.

Of its 6 completed or terminated interventional studies of FDA-regulated products, 1 (17%) have results posted.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
19 Years to 55 Years
Sexes eligible
All
Accepts healthy volunteers
Yes
Sampling method
Probability sample

Study population

SCI individuals (19 to 55 years of age) with a functionally complete or a functionally incomplete spinal cord injury will constitute the study population.

Inclusion criteria

  1. SCI individuals (19 to 55 years of age) with a functionally complete or a functionally incomplete spinal cord injury will constitute the study population. These groups will be subdivided according to whether the SCI is acute or chronic. 2. Neurologically intact, age-matched control individuals who are confined to bedrest for 5-7 days as the result of a musculoskeletal condition (eg. following a pelvic/acetabular fracture) or lumbar drain will also be recruited. 3. Healthy able bodied control volunteer subjects.

Exclusion criteria

Exclusion Criteria:

Subjects under 19 and over 55 years of age; subjects with symptomatic cardiovascular disease or problems, any unstable medical/psychiatric condition or substance abuse that is likely to affect their ability to complete the study. Individuals with SCI and active medical issues such as pressure sores, urinary tract infections, hypertension or heart disorders will be excluded from the study

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Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
51 participants (actual)
06

Study locations

1 site
  • Vancouver General Hospital, Echeleon Bldg.
    Vancouver, British Columbia, Canada
07

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Oct 1, 2019, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT00175773
Lead sponsor
University of British Columbia
Responsible party
Andrei Krassioukov (Principal Investigator, University of British Columbia) — Principal investigator
First posted
Sep 15, 2005
Start date
Nov 2004
Primary completion
Dec 2009
Completion
Dec 2009
Last update
Oct 1, 2019

Study contacts

Andrei Krassioukov, MD
principal investigator · University of British Columbia

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Sep 2019. You cannot join it, but the record below documents what was studied.

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