Ignite Creation Date:
2024-05-05 @ 11:55 AM
Last Modification Date:
2024-10-26 @ 9:16 AM
Study NCT ID:
NCT00175773
Status:
COMPLETED
Last Update Posted:
2019-10-01
First Post:
2005-09-13
Brief Title:
Mechanisms of Orthostatic Intolerance in Spinal Cord Injured Individuals and Following Bed Rest
Sponsor:
University of British Columbia
Organization:
University of British Columbia
Study Overview
Official Title:
Mechanisms of Orthostatic Intolerance in Spinal Cord Injured Individuals and Following Bed Rest
Status:
COMPLETED
Status Verified Date:
2019-09
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief 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
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 02ms 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 004-015 Hz and high-frequency power HF 015-04 Hz LF power is believed to represent sympathetic tone while HF power represents parasympathetic tone
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 02ms 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 004-015 Hz and high-frequency power HF 015-04 Hz LF power is believed to represent sympathetic tone while HF power represents parasympathetic tone
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None