Study of the Impact of Changes in Carbonemia on Microcirculation in Patients Achieving a Test Hypercapnia

Study Overview
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Brief Summary
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The microcirculatory alterations is common in circulatory failure, especially during sepsis. The severity of these changes and their sustainability are responsible of multi organ failure and ultimately death. The optimization of microcirculatory flow could be a central objective of the management of patients hospitalized in intensive care. Microcirculation includes all blood vessels of a diameter smaller than 100 micrometer. It represents the largest heat exchange surface of the body and is involved in tissue oxygenation. Microcirculatory flow is conditioned by the macrocirculation (heart rate and blood pressure) and the state of the microcirculation (thrombosis, vasoconstriction ...). The role of the CO2 in regulating microcirculatory flow is little studied. A recent work of our team and the oldest work in the literature lead to believe that CO2 has a specific role in modulating microcirculatory flow. No study to date precisely studied the impact of changes in the microcirculatory flow carbonemia . The hypocapnia test is carried out in a standardized manner by inhalation of a mixture enriched in CO2 7% allows a significant increase in carbonemia. Hypocapnia will in turn obtained by a calibrated voluntary hyperventilation test. Direct visualization of microcirculation by confocal microscopy is now considered the gold standard for exploring the microcirculation.

Official Title
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Study of the Impact of Changes in Carbonemia on Microcirculation in Patients - A Monocentric Study

Conditions
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Microcirculation, Blood Circulation

Intervention / Treatment
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* Device: confocal microscopy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients from achieving hypercapnia test the CHU of Saint-Etienne non smoking non diabetic affiliated with or entitled to a social security system Written consent Exclusion Criteria: subjects not performing the test hypercapnia in full patients with dermatological pathology at the study area patient with Raynaud's syndrome Patients with known bleeding disorders refusal to consent

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: patients with a hypercapnia test<br>confocal microscopy patients with a hypercapnia test | Device: confocal microscopy<br>* microvessel diameter measured by confocal microscopy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| microcirculatory flow (cells / min) measured by confocal microscopy | microcirculatory flow (cells / min) measured by confocal microscopy in hypocapnic patients | Day1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| microvessel diameter (micrometer) measured by confocal microscopy | microvessel diameter (micrometer) measured by confocal microscopy in hypocapnic patients | Day1 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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microcirculation, confocal microscopy, hypocapnia