Carbon Monoxide's Headache Inducing Characteristics and Effects on the Cerebral Arteries and Blood Flow

Study Overview
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Brief Summary
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In this study the investigators will research the hypothesis that the gas carbon monoxide induces headache and increases the blood flow velocity in the middle cerebral artery.

Detailed Description
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To investigate headache score and accompanying symptoms during and after inhalation of carbon monoxide. With transcranial Doppler imaging, c-scan and laser speckle the investigators will investigate changes in blood flow velocity of the middle cerebral artery (MCA), diameter of the superficial temporal artery (STA), the radial artery and facial skin perfusion.

Official Title
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Basic Research on Carbon Monoxide's Headache Inducing Characteristics and Effects on the Cerebral Arteries and Blood Flow in a Humane Experimental Headache Model

Conditions
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Headache, Migraine

Intervention / Treatment
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* Other: Carbon monoxide
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy volunteers Aged 18-50 50-100 kg Exclusion Criteria: Tension type headache more than once/month Other primary headaches Daily medication except contraceptives Drug taken within 4 times the halflife for the specific drug except contraceptives Pregnant or lactating women Exposure to radiation within the last year Headache within the last 24 hours before start of trial Hypertension Hypotension Respiratory or cardiac disease Smoking Primary relatives with current or previous migraine

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: carbon monoxide<br>Inhalation of carbon monoxide up to a carboxyhemoglobin concentration of 12% and 22%. | Other: Carbon monoxide<br>* carbon monoxide, 4.7, Purity 99.997, inhalation of carbon monoxide in a volume corresponding to carboxyhemoglobin 10 and 20%, calculated from baseline Hg and body mass.<br>|
| Placebo Comparator: placebo<br>Atmospheric air | Other: Placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Headache scores | Comparison between carbon monoxide and placebo (atmospheric air) | 12 h | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood flow velocity | Carbon monoxide induced changes in blood flow velocity in the middle cerebral artery before and after inhalation. | 0-180 min after inhalation | 
| Artery circumference | Carbon monoxide induced changes in the superficial temporal artery and the radial artery before and after inhalation. | 0-180 min | 
| Facial blood flow | Carbon monoxide induced changes in facial blood flow before and after inhalation. | 0-180 min | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Headache, Carbon monoxide, Migraine