The goal of this clinical trial is to determine if perfusion index (PI) can reliably predict changes in systolic blood pressure (SBP) in persons with spinal cord injury (SCI) during a cool temperature challenge. Participants with SCI can be 18-75 years of age, male or female, neurological level of injury C4-T12, ASIA Impairment Scale (AIS: A or B: motor complete) or gender and healthy age-matched able-bodied (AB) controls.
The main question this study aims to answer is: can PI reliably predict change in SBP during a cool temperature challenge? We hypothesize that PI can be used as a biomarker of SBP in persons with SCI.
Researchers will compare the relationship of 1) changes in PI and SBP and 2) relationship of changes in other vital signs to SBP, during the cool temperature challenge. The researchers aim to determine if PI can be used as a biomarker of SBP in persons with SCI during a cool temperature challenge (experimental group/arm). Able-bodied controls (control group/arm) will receive the same intervention (cool challenge) as the experimental group.
During the study, participants will be asked to wear only shorts and a T-shirt so that their skin can be exposed to the warm and cool temperatures of the 2 rooms.
We will put put on non-invasive sensors (taped or attached on the surface of your body) to measure PI, BP, and other vital signs. We will record these measurements while you are seated in a wheelchair for 10 minutes in a warm room and up to 90 minutes in a cool room.
You have had a spinal cord injury (SCI: C4-T12) for more than one year and the SCI was graded as ASIA Impairment Scale (AIS) A or B (unable to voluntarily move your legs)
You can also be a gender and age-matched (±5 years) able-bodied (AB) control subject (similar gender and age to a subject with SCI).
Subjects with SCI and AB controls must be between 18 and 75 years of age.
If you are going to participate, you must avoid caffeine and alcohol, maintain normal salt and water intake, and avoid strenuous exercise for 24 hours prior to the study visit.
You have cardiovascular, kidney, or untreated thyroid disease
You have a traumatic brain injury (TBI)
You have diabetes mellitus
You have an acute illness or infection