Neuromodulation of Blood Pressure Using Transcutaneous Spinal Stimulation in Chronic Spinal Cord Injury
Kessler Foundation
Summary
This project will investigate the effect of spinal cord transcutaneous stimulation on blood pressure in individuals with a chronic spinal cord injury who experience blood pressure instability, specifically, orthostatic hypotension (a drop in blood pressure when moving from lying flat on your back to an upright position). The main questions it aims to answer are: 1. What are the various spinal sites and stimulation parameters that normalize and stabilize blood pressure during an orthostatic provocation (70 degrees tilt)? 2. Does training, i.e., exposure to repeated stimulation sessions, have an effect on blood pressure stability? Participants will undergo orthostatic tests (lying on a table that starts out flat, then tilts upward up to 70 degrees), with and without stimulation, and changes in their blood pressure will be evaluated.
Description
Cardiovascular (CV) control in persons with a high level (thoracic level T6 or above) spinal cord injury (SCI) is often impaired, resulting in short and long-term health complications and a decline in quality of life. Orthostatic hypotension (OH), a significant decrease in blood pressure (BP) when moving from lying flat (supine) to an upright position, appears early after injury and is frequently accompanied by dizziness, weakness, fatigue, and even syncope. In the long term, while symptoms are typically diminished, it still clinically occurs in 50% of individuals with a cervical injury. The p…
Eligibility
- Age range
- 18–75 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Spinal cord injury for greater than or equal to 6 months * Injury level ≥ T6 (thoracic level) * American Spinal Injury Association (ASIA) Impairment Scale (AIS) A-D * Exhibits at least one of the following hypotensive symptoms: 1. Baseline hypotension - resting supine or seated systolic blood pressure(SBP) \< 90mmHg; 2. SBP drop ≥ 20 mmHg within 5 minutes of assuming seated position; 3. Symptoms of orthostasis with a drop of SBP (\<90mmHg) from supine to sitting Exclusion Criteria: * Current illness (infection, a pressure injury that might interfere with the int…
Interventions
- DeviceBiostim-5 transcutaneous spinal stimulator
Transcutaneous stimulation of the spinal cord. Mapping will be performed to determine sites for optimal modulation of blood pressure. During each mapping day, with participants in a supine or seated position, electrodes will be placed on the midline of one of the following spinous processes: C5/6, T7/8, T11/12, L1/2 and S1/2. Stimulation intensity will start at 5 mA and gradually increased in 5 mA increments up to 100 mA. The frequency will be 2 or 30 Hz. Profiles will be established to guide selection of optimal site locations for blood pressure modulation. The profile chosen will be used during training and testing. During testing, stimulation will be applied using the selected profile in order to normalize SBP to the range of 110-120 mmHg and stabilize it within this range during a 30-min tilt test. On each session during the 2-week training-period, stimulation will be applied for 30 minutes using the selected profile, while the participant remains in a seated position.
- Diagnostic TestTilt-table orthostatic stress testing
While lying supine, participants will be strapped to a Hi-Low tilt-table bed. The bed will gradually be tilted to a 70 degrees tilt, during which time continuous hemodynamic measures will be recorded. This position will be maintained for 30 minutes. During some of the sessions, the tilt test will be accompanied by spinal stimulation.
Location
- Kessler FoundationWest Orange, New Jersey