Recruiting

BioFLO

Sponsor:

University of Florida

Code:

NCT06011876

Conditions

Spinal Cord Injuries

Eligibility Criteria

Sex: All

Age: 18 - 70

Healthy Volunteers: Not accepted

Interventions

Acute Intermittent Hypoxia (AIH)

Acute Intermittent Hypercapnic-Hypoxia (AIHH)

Sham AIH

Study Details

Brief summary:

Acute intermittent hypoxia (AIH) involves brief (1 min), repeated episodes (\~15) of breathing low oxygen air to stimulate spinal neuroplasticity. Animal and human studies show that AIH improves motor function after spinal cord injury, particularly with slightly increased carbon dioxide (hypercapnic AIH; AIHH) and task-specific training. Using a double blind cross-over design, the study will test whether AIHH improves breathing more than AIH and whether specific genetic variations are related to individuals' intervention responses.

Conditions

Spinal Cord Injuries

Study ID

NCT06011876

Start date

Dec 21, 2023

Status verified date

Nov, 2025

Completion date

Sep, 2027

Anticipated

Primary completion date

Jul, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. Adults 18-70 years of age
2. Chronic incomplete SCI ≥ 1 year at or below C1-T12

  • Incomplete SCI based on residual sensory and motor function below the level of the injury or injury classification of B, C, D at initial screening according to the American Spinal Injury Association Impairment Classification and the International Standards for the Neurological Classification of SCI.

-OR- Chronic complete SCI ≥1 year at or below C4-T12
  • Complete SCI based on the absence of residual sensory or motor function below the level of injury or injury classification of A at initial screening according to the American Spinal Injury Association Impairment Classification and the International Standards for the Neurological Classification of SCI.
3. Medically stable with physician clearance
4. SCI due to non-progressive etiology
5. 20% impairment in maximal inspiratory, maximal expiratory pressure generation, or both relative to normative values

Exclusion Criteria:

1. Current diagnosis of an additional neurologic condition such as Multiple Sclerosis, Parkinson disease, stroke, or brain injury
2. Severe illness or infection, including non-healing decubitus ulcers, untreated bladder or urinary tract infections, cardiovascular disease, lung disease, active heterotopic ossification, or uncontrolled hypertension
3. Severe neuropathic pain
4. Known pregnancy
5. Severe recurrent autonomic dysreflexia

Exclusion for involvement in TMS - History of seizure disorder, uncontrolled migraines, presence of cardiac pacemaker, metal implants in skull, medications that lower seizure threshold.

Study Design

Enrollment

62 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Single-session testing days

Participants will complete three separate single-session testing days. Baseline testing will be performed, then on each day, participants will receive AIH, AIHH, and sham AIH in random order. Post-testing will occur after each intervention.

experimental: Respiratory strength training blocks

Participants will complete three separate respiratory strength training blocks. In each block, participants will receive 5 days of AIH, 5 days of AIHH, and 5 days of sham AIH in random order, followed by respiratory strength training. Each block will include 5 days of intervention and training, and post-testing 1, 3, and 7 days after intervention and training has concluded.

Interventions

Acute Intermittent Hypoxia (AIH)

AIH (acute intermittent hypoxia) consists of short episodes of low oxygen (9% O2).

Acute Intermittent Hypercapnic-Hypoxia (AIHH)

AIHH consists of short episodes of low oxygen (9% O2) and elevated carbon dioxide (4% CO2).

Sham AIH

A single session of sham AIH with episodes of normal room air (21% O2).

Primary outcome measure

  • Change in motor evoked potential [ Time Frame: Baseline, and 45-60 minutes after intervention on AIH day, AIHH day, and Sham AIH day ]
  • Change in maximal inspiratory pressure [ Time Frame: Baseline, 1 day, 3 days, and 7 days after intervention blocks (daily AIH + respiratory strength training, daily AIHH + respiratory strength training, daily sham AIH + respiratory strength training.) ]
  • Change in maximal expiratory pressure [ Time Frame: Baseline, 1 day, 3 days, and 7 days after intervention blocks (daily AIH + respiratory strength training, daily AIHH + respiratory strength training, daily sham AIH + respiratory strength training.) ]

Central Contacts and Locations

Central contacts

Locations

Brooks Rehabilitation

Recruiting

Jacksonville, Florida, United States, 32216

Contacts

Emily J. Fox, MHS, DPT, PhD

(904) 742-2500ejfox@phhp.ufl.edu

More Information

Sponsor

University of Florida

Last update posted

Nov 5, 2025

Last verified

Nov, 2025

Keywords

  • acute intermittent hypoxia
  • spinal cord injury
  • breathing
  • motor function

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Florida on 2025-11-05.