Effect of Hyperbaric Oxygen Therapy on Healthy Volunteers Microcirculation
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 15
- 试验地点
- 2
- 主要终点
- Changes in proportion of perfused vessel (PPV)
研究概览
简要总结
Previous studies shoes that hyperoxia alters microcirculation.The investigators hypothesize that hyperbaric may restore microcirculation integrity. This hypothesis is supported by a recent study in rabbits, but no data exists for humans.
The study will expose fifteen healthy volunteers to a succession of different fraction of inspired oxygen and barometric pressure and assess microcirculatory and macrocirculatory changes via sidestream dark field videomicroscopy, near-infrared spectroscopy, Laser Doppler, transthoracic echocardiography and bio-impedancemetry at every step.
详细描述
Microcirculation alterations and hyperoxia are known to alter ICU-patients' prognostic.
Studies have shown that hyperoxia alters healthy volunteers' microcirculation, whereas hyperbaric oxygen therapy is commonly used to facilitate cicatrization. There seems to be a paradox. A recent study in rabbits has given some evidences that hyperbaria may restore microcirculation integrity, but to date, there is no such evidences in human.
To study hyperoxia and hyperbaric induced changes in micro and macrocirculation, fifteen healthy volunteers will be exposed to successive variations of inspired oxygen fraction and barometric pressure according to a predefine sequence so that only one parameter will change from a condition to the next one :
- FiO2 0.21 - 1 ATA
- FiO2 1 - 1 ATA
- FiO2 1 - 2.5 ATA
- FiO2 0.21 - 2.5 ATA
- FiO2 0.21 - 1 ATA
At each time, and after a 30 minutes period of exposure, measures will be made using SDF-microscopy, Laser Doppler and NIRS to assess microcirculation.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 64 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •To provide a medical certificate of fitness to dive (< 1 year)
- •Consent given for study participation
- •French health insurance affiliated
排除标准
- •Temporary or definitive contra-indication to dive
- •Pregnancy or < 18 years of age
- •Precedent dive < 24 hours
- •Under a legal protection measure
- •Medical history of a disease known to alter microcirculation
结局指标
主要结局
Changes in proportion of perfused vessel (PPV)
时间窗: 30 minutes after hyperbaric hyperoxia exposure (FiO2 1 - 2.5 ATA)
Proportion of perfused vessel assessed by Sidestream dark field microscopy on the sublingual mucosa
次要结局
- Validation of cardiac output assessed by bioimpedancemetry under hyperbaric condition(30 minutes after FiO2 1 - 2.5 ATA exposure)
- Changes in area of hyperaemia after a vaso-occlusion test(30 minutes after FiO2 1 - 2.5 ATA exposure)
- Changes in proportion of perfused vessel (PPV)(30 minutes after FiO2 0.21 - 2.5 ATA exposure)
- Changes in hyperemic reaction after a vaso-occlusion test(30 minutes after FiO2 1 - 2.5 ATA exposure)
- Changes in proportion of perfused vessel (PPV)(30 minutes after FiO2 1 - 1 ATA exposure)