Clinical trial NCT05761756: Oxygen Toxicity: Mechanisms in Humans
Official title: Applied Physiology of Oxygen Toxicity: Mechanisms in Humans
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Oxygen Toxicity
Hypercapnia
Seizures
Lead sponsor: Duke University
Sponsor class: OTHER
First posted: 2023-03-09
Enrollment: 62
Sex: ALL
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: The goal of this clinical trial is to learn about the mechanisms of oxygen toxicity in scuba divers. The main questions it aims to answer are:

* How does the training of respiratory muscles affect oxygen toxicity?
* How do environmental factors, such as sleep deprivation, the ingestion of commonly utilized medications, and chronic exposure to carbon dioxide, impact the risk of oxygen toxicity?
* How does immersion in water affect the development of oxygen toxicity?

Participants will be asked to do the following:

* Undergo a basic screening exam composed of health history, vital signs, and some respiratory function tests
* Train their respiratory muscles at regular intervals
* Exercise on a cycle ergometer both in dry conditions and underwater/under pressure in the context of medication, sleep deprivation, or carbon dioxide exposure

Researchers will compare the performance of each subject before and after the possible interventions described above to see if there are changes in exercise performance, respiratory function, cerebral blood flow, and levels of gene expression.


Eligibility criteria: Inclusion Criteria:

* Equal numbers of male and female
* Non-smokers
* Aged 18-45 years
* Males will be required to have VO2 peak \> or equal to mL/kg min
* and females \> or equal to 30 mL/kg min

Exclusion Criteria:

* Pregnancy
* Cardiorespiratory disease, including hypertension
* Neuromuscular disease
* Anemia
* History of hemoglobinopathy, including sick cell disease and trait

Primary outcomes:
measure: Hypercapnic ventilatory response
timeFrame: 3 months
Secondary outcomes:
measure: Lactate, pyruvate
timeFrame: 3 months
measure: Arterial PCO2
timeFrame: Baseline and after Intervention/arm
measure: Integrated diaphragmatic function (IDF) composite score
timeFrame: Baseline and after Intervention/arm, which averages 3 months
measure: Cerebral blood oxygenation
timeFrame: Baseline and after Intervention/arm, which averages 3 months
measure: Hormone levels (leptin, adiponectin)
timeFrame: Baseline and after Intervention/arm, which averages 3 months
Other outcomes:
Locations:
city: Durham
country: United States
facility: Duke University Health Sustem
state: North Carolina
Study officials:
affiliation: Duke University
name: Derek B Covington, MD
role: PRINCIPAL_INVESTIGATOR
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