AI-Guided Predictions of Blood Pressure Dysregulation Using Perfusion Index as a Novel Biomarker in Persons With Spinal Cord Injury

NCT07699094 | Recruiting

• 3 other identifiers: 1930980RFA # 20465SFS # PART72025
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Spinal Cord Injuries (SCI); Blood Pressure; Thermoregulation; Perfusion Index

Outcome Measures

Primary Outcomes (2)

• Perfusion Index (PI)

  Perfusion index (PI: ranging from 0.02 to 20) reflects the ratio of pulsatile (arterial) blood flow to non-pulsatile static blood flow. PI will be continuously collected using Masimo Radical-7 pulse oximeters (Masimo Corp., Irvine, CA) attached to three sites: an ear, a finger, and a toe. This multi-site data will serve as the primary independent predictor variable of SBP in the AI/machine learning models.

  Continuously recorded during 10 minutes of the baseline thermoneutral (27°C) phase and throughout the cool thermal challenge (18°C) phase for up to 90 minutes.

• Systolic Blood Pressure (SBP)

  Beat-to-beat systolic blood pressure (SBP: mmHg) will be continuously collected via a finger-cuff sensor using the VitalStream-CM wireless hemodynamic monitor (CareTaker Medical LLC, Charlottesville, VA). SBP will serve as the primary target dependent variable that we are trying to predict to evaluate sympathetic/vascular reactivity and to train the non-invasive machine learning prediction algorithms.

  Continuously recorded during 10 minutes of the baseline thermoneutral (27°C) phase and throughout the cool thermal challenge (18°C) phase for up to 90 minutes.

Study Arms (2)

Participants with SCI: Cool temperature challenge

EXPERIMENTAL

Participants with SCI will be transferred from a thermoneutral room (27°C) to a cool thermal chamber (18°C) for up to 90 minutes to determine change in 1) perfusion index and 2) systolic blood pressure.

Other: Controlled Cool Thermal Challenge (18°C)

Able-bodied participants (Control): Cool temperature challenge

ACTIVE COMPARATOR

Able-bodied participants will be transferred from a thermoneutral room (27°C) to a cool thermal chamber (18°C) for up to 90 minutes to determine change in 1) perfusion index and 2) systolic blood pressure.

Other: Controlled Cool Thermal Challenge (18°C)

Interventions

Controlled Cool Thermal Challenge (18°C) OTHER

Participants with SCI will undergo a controlled, non-invasive cool thermal challenge of 18°C (64.4°F) in a climate-controlled chamber for up to 90 minutes. Participants will remain seated in their wheelchair while wearing a standard T-shirt and shorts to ensure uniform skin exposure. Continuous non-invasive monitoring of perfusion index and blood pressure will be performed throughout the baseline of 27°C (80°F) and cool challenge 18°C (64.4°F) phases to evaluate their relationship.

Participants with SCI: Cool temperature challenge

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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 may not qualify if:

• 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
• You are dehydrated
• You smoke
• You are pregnant
• You have broken, inflamed, or otherwise fragile skin
• Your Body Mass Index (BMI) is more than 30 kg/m2

Sponsors & Collaborators

• James J. Peters Veterans Affairs Medical Center: lead

Study Sites (1)

James J Peters VA Medical Center

The Bronx, New York, 10468, United States

RECRUITING

MeSH Terms

Conditions

Spinal Cord Injuries

Condition Hierarchy (Ancestors)

Spinal Cord Diseases; Central Nervous System Diseases; Nervous System Diseases; Trauma, Nervous System; Wounds and Injuries

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: FED
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: 12 Subjects with Spinal Cord Injury 12 Subjects who are Able Bodied

Study Record Dates

• First Submitted: July 7, 2026
• First Posted: July 13, 2026
• Study Start: July 1, 2026
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2028
• Last Updated: July 13, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will share

Locations

US (1)