Acute Intermittent Hypoxia to Improve Airway Protection in Chronic Traumatic Brain Injury

January 7, 2026 updated by: University of Florida
Acute intermittent hypoxia (AIH) involves 1-2min of breathing low oxygen air to stimulate neuroplasticity. Animal and human studies show that AIH improves motor function after neural injury, particularly when paired with task-specific training. Using a double blind cross-over study we will test whether AIH and task-specific airway protection training improves airway protection more than training alone in individuals with chronic mild-moderate traumatic brain injury (TBI).

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Recent studies have found that acute intermittent hypoxia (AIH)-or repetitive exposure to brief episodes of low inspired oxygen--is a promising new strategy that can help restore motor function by promoting neuroplasticity throughout the central nervous system (CNS). Both rodent and human studies show that motor function is further enhanced when AIH is paired with task-specific training/rehabilitation (TST). Therefore, this study will investigate the therapeutic potential of combining AIH with a task-specific airway protection training. We propose that the combined use of AIH + TST will enhance the magnitude and duration of TST training alone in individuals with chronic traumatic brain injury.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
5

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • Florida
      • Jacksonville, Florida, United States, 32209
        • University of Florida

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adults aged 21-80 years
  • A mild to moderate traumatic brain injury (TBI) confirmed by medical records
  • A Glasgow Coma Scale score between 9-15
  • Able to consent independently
  • Women of child-bearing age must be comfortable confirming a negative pregnancy prior to participating in the study

Exclusion Criteria:

  • Other neurological diagnoses or a diagnosis of a severe psychiatric disorder
  • Severe aphasia preventing a participant from understanding the protocol and consent form
  • Pre-existing hypoxic pulmonary disease
  • History of obstructive lung diseases such as chronic obstructive pulmonary disease (COPD) or significant asthma)
  • Severe hypertension (>160/100)
  • History of head and neck cancer
  • Allergy to barium sulfate
  • Ischemic cardiac disease

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Active Comparator: AIH + TST
Participants will complete a 5-day intervention blocks where they receive daily AIH followed by task specific airway protection training 60 minutes after the AIH exposure. Each exposure involves a 1-minute delivery of low oxygen (9-11% inspired O2), followed by a 1.5-min interval of room air breathing (21% O2). This method of waiting 45-60 minutes after the delivery of AIH and prior to engaging in task-specific training/rehabilitation enables sufficient time to increase brain derived neurotrophic factor (BDNF) following AIH, thereby augmenting the impact of task-specific training.
Other: Acute Intermittent Hypoxia (AIH)
Acute intermittent hypoxia refers to brief (acute), repetitive (intermittent) episodes of breathing oxygen-deprived air (hypoxia) alternating with breathing ambient room air.
Behavioral: Task specific Airway Protection Training
The vLVC maneuver involves training participants to volitionally prolong closure of the laryngeal vestibule during swallowing, beginning with swallow onset and sustaining closure for at least 2 seconds.
Other Names:
  • volitional laryngeal vestibule closure (vLVC) training
Sham Comparator: Sham AIH + TST
Participants will complete a 5-day intervention blocks where they receive sham AIH followed by task specific airway protection training 60 minutes after the AIH sham exposure. Sham AIH will be delivered using methods identical to AIH, except a normoxic gas mixture (~21% O2) will be delivered. The gas mixture with normoxic air will effectively serve as a sham.
Behavioral: Task specific Airway Protection Training
The vLVC maneuver involves training participants to volitionally prolong closure of the laryngeal vestibule during swallowing, beginning with swallow onset and sustaining closure for at least 2 seconds.
Other Names:
  • volitional laryngeal vestibule closure (vLVC) training
Other: Sham AIH
Sham AIH will be delivered using methods identical to AIH, except a normoxic gas mixture (~21% O2) will be delivered. The gas mixture with normoxic air will effectively serve as a sham.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Duration of laryngeal vestibule closure (dLVC)
Time Frame: Pre-intervention, 1 day after intervention block and 1-week post intervention
Time in (msec) the laryngeal vestibule stays closed during a swallow
Pre-intervention, 1 day after intervention block and 1-week post intervention
Time to laryngeal vestibule closure (Time-to-LVC)
Time Frame: Pre-intervention, 1 day after intervention block and 1-week post intervention
Time in (msec) it takes to close the laryngeal vestibule after swallow initiation
Pre-intervention, 1 day after intervention block and 1-week post intervention

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Penetration-Aspiration Scale Scores
Time Frame: Pre-intervention, 1 day after intervention block and 1-week post intervention
The penetration-aspiration scale (PAS) will be used to assess penetration or aspiration; the PAS is an 8-point scale that ranges from 1 (no penetration/aspiration) to 8 (aspiration with no cough response).
Pre-intervention, 1 day after intervention block and 1-week post intervention

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Florida

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Alicia Z Vose, Ph.D., University of Florida

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
August 30, 2024

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
September 30, 2025

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
September 30, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
July 19, 2024

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 24, 2024

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
July 25, 2024

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
January 9, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 7, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2024

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • IRB202301156

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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