Abstract
BACKGROUND: Transcutaneous spinal cord stimulation (tSCS) has shown evidence of leveraging intact neural circuits to increase blood pressure (BP) in hypotensive people with chronic spinal cord injury (SCI). OBJECTIVES: The primary aim is to determine the safety and feasibility of using tSCS to promote seated systolic BP (SBP) within a target range of 110-130 mm Hg and to mitigate the fall in BP with transition to an upright position in hypotensive participants during acute inpatient rehabilitation (AIR) following SCI. DESIGN/METHODS: Cathode placement on the spine will be randomized among 4 sites: T7/8, T9/10, T11/12, and L1/2. Mapping for other stimulation parameters includes waveform (monophasic, biphasic, pseudo-monophasic), frequency (30, 60, 120 Hz), use of a carrier frequency (0, 10 kHz), and stimulation amplitude (0-100 mA). Each mapping session will consist of 2 sit-up tests, one without stimulation followed by one with stimulation. During the sit-up test with stimulation, intensity will be slowly increased to 30 mA with continuous monitoring of BP, heart rate, pain, and symptoms of orthostatic hypotension (OH) and autonomic dysreflexia (AD). Once 30 mA is reached, brachial BP will be monitored for 5 minutes. If below the target SBP range, stimulation intensity will be increased in increments of 5 to 10 mA until one of the following occurs: (1) SBP is within the target range, (2) stimulation is intolerable, (3) 100 mA is reached, or (4) stimulation is delivered for 30 minutes. Safety and feasibility will be measured by assessing burn frequency, pain level, and symptoms of AD and OH along with scheduling compliance.