Effect of Hyperbaric Oxygen Therapy on Microcirculation

Hyperbaric Oxygen Therapy Clinical Trial

— MICROHB  

Official title:

Effect of Hyperbaric Oxygen Therapy on Healthy Volunteers Microcirculation

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03980210
• Other study ID #: 2018_63
• Secondary ID: 2019-A00053-54
• Status: Completed
• Phase: N/A
• Start date: June 14, 2019
• Est. completion date: July 25, 2019

Study information

• Verified date: September 2019
• Source: University Hospital, Lille
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

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.

Description:

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 :

1. FiO2 0.21 - 1 ATA

2. FiO2 1 - 1 ATA

3. FiO2 1 - 2.5 ATA

4. FiO2 0.21 - 2.5 ATA

5. 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.

As previously described, macrocirculation can modify microcirculation due to a mechanism called hemodynamic coherence.

Hence, the investigators planned to assess macrocirculation changes at every step of the protocol using bioimpedancemetry and transthoracic echocardiography.

Each volunteer will be his own control, using the first measurements (condition 1. FiO2 0.21

• 1 ATA) as reference.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 15
• Est. completion date: July 25, 2019
• Est. primary completion date: July 25, 2019
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 64 Years

Eligibility

Inclusion Criteria:

• To provide a medical certificate of fitness to dive (< 1 year)

• Consent given for study participation

• French health insurance affiliated

Exclusion Criteria:

• 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

Related Conditions & MeSH terms

• Hyperbaric Oxygen Therapy

Intervention

Procedure:
• Hyperbaric oxygen therapy
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

Locations

Country	Name	City	State
France	Hôpital Roger Salengro, CHU	Lille

Sponsors (1)

Lead Sponsor	Collaborator
University Hospital, Lille

Country where clinical trial is conducted

France, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Changes in proportion of perfused vessel (PPV)	Proportion of perfused vessel assessed by Sidestream dark field microscopy on the sublingual mucosa	30 minutes after hyperbaric hyperoxia exposure (FiO2 1 - 2.5 ATA)
Secondary	Changes in proportion of perfused vessel (PPV)	Proportion of perfused vessel assessed by Sidestream dark field microscopy on the sublingual mucosa	30 minutes after FiO2 1 - 1 ATA exposure
Secondary	Changes in proportion of perfused vessel (PPV)	Proportion of perfused vessel assessed by Sidestream dark field microscopy on the sublingual mucosa	30 minutes after FiO2 0.21 - 2.5 ATA exposure
Secondary	Changes in hyperemic reaction after a vaso-occlusion test	Area under curve assessed by near-infrared spectroscopy	30 minutes after FiO2 1 - 2.5 ATA exposure
Secondary	Changes in area of hyperaemia after a vaso-occlusion test	Area under curve assessed by Laser-Doppler	30 minutes after FiO2 1 - 2.5 ATA exposure
Secondary	Validation of cardiac output assessed by bioimpedancemetry under hyperbaric condition	Comparison with transthoracic echocardiography	30 minutes after FiO2 1 - 2.5 ATA exposure