Applied Physiology of Oxygen Toxicity: Mechanisms in Humans
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 62
- 试验地点
- 1
- 主要终点
- Hypercapnic ventilatory response
研究概览
简要总结
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Single (Investigator)
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •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
排除标准
- •Pregnancy
- •Cardiorespiratory disease, including hypertension
- •Neuromuscular disease
- •History of hemoglobinopathy, including sick cell disease and trait
研究组 & 干预措施
Sleep Deprivation
Effect of sleep deprivation on HCVR and arterial PCO2 during submersed rest and exercise at 98 fsw. Ten subjects will be tested before and after 24 hours of sleep deprivation. The order of sleep deprivation vs. control will be randomized. Measurements at 98 fsw will be obtained at rest and during 10 minutes of moderate exercise in thermoneutral (29-30°C) water.
干预措施: Sleep Deprivation (Behavioral)
Caffeine
Effect of caffeine and methylphenidate on HCVR and arterial PCO2 during submersed rest and exercise at 98 fsw. Twenty subjects will be similarly sleep-deprived, tested as above and then re-tested tested following oral administration of administration of either oral caffeine (N=10) or methylphenidate (N=10). Pre-dive caffeine will be administered 500 mg orally [59]. Pre-dive methylphenidate will be administered as a single dose of 5 mg [60]. The order of drug administration vs. control will be randomized. Measurements at 98 fsw will be obtained at rest and during 10 minutes of moderate exercise in thermoneutral (29-30°C) water. fNIRS will be used to assess cerebral oxygenation and regional blood volume.
干预措施: Caffeine (Drug)
Methylphenidate
Effect of caffeine and methylphenidate on HCVR and arterial PCO2 during submersed rest and exercise at 98 fsw. Twenty subjects will be similarly sleep-deprived, tested as above and then re-tested tested following oral administration of administration of either oral caffeine (N=10) or methylphenidate (N=10). Pre-dive caffeine will be administered 500 mg orally [59]. Pre-dive methylphenidate will be administered as a single dose of 5 mg [60]. The order of drug administration vs. control will be randomized. Measurements at 98 fsw will be obtained at rest and during 10 minutes of moderate exercise in thermoneutral (29-30°C) water. fNIRS will be used to assess cerebral oxygenation and regional blood volume.
干预措施: Methylphenidate (Drug)
Carbon Dioxide Exposure
Effect of simulated chronic CO2 exposure on HCVR and arterial PCO2 during submersed rest and exercise at 98 fsw. Ten subjects will be studied before and after induction of metabolic alkalosis as described above with daily oral administration of sodium bicarbonate. Oral bicarbonate to simulate hypercapnia exposure will seek to increase serum bicarbonate to 30 mM/L via daily oral intake of 6 teaspoons of NaHCO3 for five days. Subsequently, blood will be drawn and intake adjusted as necessary [61]. The order of alkalization vs. control will be randomized. Measurements at 98 fsw will be obtained at rest and during 10 minutes of moderate exercise in thermoneutral (29-30°C) water.
干预措施: Carbon Dioxide (Drug)
结局指标
主要结局
Hypercapnic ventilatory response
时间窗: 3 months
次要结局
- Cerebral blood oxygenation(Baseline and after Intervention/arm, which averages 3 months)
- Hormone levels (leptin, adiponectin)(Baseline and after Intervention/arm, which averages 3 months)
- Lactate, pyruvate(3 months)
- Integrated diaphragmatic function (IDF) composite score(Baseline and after Intervention/arm, which averages 3 months)
- Arterial PCO2(Baseline and after Intervention/arm)