BioFLO for Respiratory Recovery in SCI

University of Florida

Status: Enrolling

Conditions: Spinal Cord Injuries

Treatments: Other: Sham AIH; Other: Acute Intermittent Hypercapnic-Hypoxia (AIHH); Other: Acute Intermittent Hypoxia (AIH)

Study type: Interventional

Funder types: Other; Other U.S. Federal agency

Identifiers

NCT06011876

W81XWH2210478 (Other Grant/Funding Number)

IRB202202891

Details and patient eligibility

About

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.

Full description

This study will consist of two parts - single-session testing days, and respiratory strength training blocks. If a participant is not eligible to enroll in single-day testing, they will be asked to enroll in only the respiratory strength training blocks.

On single-session testing days, participants will be asked to come in on three separate days they will complete a battery of tests, then be given one of three interventions, and then complete the same battery of tests. The three interventions are acute intermittent hypoxia (AIH), acute intermittent hypercapnic-hypoxia (AIHH), or sham acute intermittent hypoxia (sham AIH). These interventions are explained in more detail below.

During respiratory strength training blocks, participants will receive five days of AIH, AIHH, or sham AIH in combination with respiratory strength training, which uses small hand-held devices to strengthen the muscles used for breathing. Participants will be asked to complete all three blocks to receive all three interventions. In addition to 5 days of interventions and respiratory strength training, the respiratory strength training blocks include testing 1 day, 3 days, and 7 days after the 5 days of respiratory strength training.

Enrollment: 62 estimated patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

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.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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62 participants in 2 patient groups

Single-session testing days

Experimental group

Description:

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.

Treatment:

Other: Acute Intermittent Hypercapnic-Hypoxia (AIHH)

Other: Acute Intermittent Hypoxia (AIH)

Other: Sham AIH

Respiratory strength training blocks

Experimental group

Description:

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.

Treatment:

Other: Acute Intermittent Hypercapnic-Hypoxia (AIHH)

Other: Acute Intermittent Hypoxia (AIH)

Other: Sham AIH