The Role of Heliox in Respiratory Control

Conditions

• Work of Breathing

Eligibility Criteria

Sex

ALL

Age

18 Years - 40 Years

Healthy Volunteers

Accepted

Interventions

• Heliox inspirate — DRUG
  This intervention corresponds to Arm 1 titled "room air and heliox inspirate". This corresponds with the first phase/period of this study.

Study Details

Warfighters are frequently exposed to environments and life-support systems that increase breathing resistance and the work of breathing (WOB), such as aircraft on-board oxygen generation systems and underwater breathing apparatuses. Elevated WOB increases the perception of breathing difficulty (dyspnea) and has been associated with impaired cognitive performance, including slower reaction time and reduced accuracy during attention-demanding tasks. These effects are particularly concerning in operational settings that require rapid decision-making and precise motor responses. Despite growing recognition of this issue, critical gaps remain regarding strategies to mitigate the perceptual and cognitive consequences of elevated inspiratory resistance, especially under realistic operational stressors. The objective of this study is to determine whether reducing mechanical WOB alters breathing perception and cognitive performance during inspiratory resistance. Participants will breathe either normal-density air or a low-density helium-oxygen gas mixture (heliox) to determine whether reducing mechanical WOB lowers perceived breathing effort and improves cognitive function.

Key Dates

Start date

Feb 3, 2026

Status verified

Mar 2026

Primary completion

May 31, 2027

Completion

May 31, 2027

Study Design

Enrollment

15 participants (estimated)

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Arms

• Active Comparator: Room Air, then Heliox Inspirate
  Participants will complete 2 full length breathing tasks, one under each condition. The order of condition exposure will be assigned via randomization.
• Active Comparator: Heliox Inspirate, then Room Air
  Participants will complete 2 full length breathing tasks, one under each condition. The order of condition exposure will be assigned via randomization.

Primary Outcome Measure

Change in Stroop Color-Word Test Time Performance [ Time Frame: Before and after each Day 1 breathing task (approximately 60 minutes in duration) ]

Central Contacts

• Timothy D Mickleborough, PhD
  812-855-0753
  [email protected]

Locations (1)

Find similar trials in Bloomington, IN

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