Redistribution of Pulmonary Perfusion During Bronchoconstriction in Asthma

NCT01547286 NA COMPLETED Results posted

Asthma is a disease of rapidly increasing incidence that already affects more than 17 million people in the United States alone. It has long been known that areas of severely reduced airflow occur in asthma and contribute significantly to the impairment of gas exchange in this disease. However, the extent to which local blood flow changes during an asthmatic attack is unclear. The purpose of this study is using Positron Emission Tomography - Computed Tomography imaging to evaluate how the blood flow changes in the lungs during an asthma attack induced by allergens.

Details

Lead sponsor	Massachusetts General Hospital
Phase	NA
Status	COMPLETED
Enrolment	7
Start date	2012-05
Completion	2013-10

Conditions

• Asthma
• Atopy

Interventions

• Standardized Cat Allergen Extract and Standardized Dust Mite Allergen
• Computed Tomography imaging, functional Positron Emission Tomography imaging
• Nebulized methacholine inhalation

Primary outcomes

• Percentage Change in the Ratio of Mean-normalized Perfusion Within Ventilation Defective Regions Relative to Outside — 3 hours after allergen administration
  Blood flow relative to the mean blood flow of the lung (mean normalized perfusion) inside areas that have reduced ventilation (Vdefs) relative to outside the Vdefs. Or, another way of writing this is: (Blood flow inside Vdefs/mean blood flow of the lung)/(Blood flow outside Vdefs/mean blood flow of the lung).
• Percentage Change in the Ratio of Mean-normalized Perfusion Within Ventilation Defective Regions Relative to Outside — 7 hours after allergen administration
  Blood flow relative to the mean blood flow of the lung (mean normalized perfusion) inside areas that have reduced ventilation (Vdefs) relative to outside the Vdefs. Or, another way of writing this is: (Blood flow inside Vdefs/mean blood flow of the lung)/(Blood flow outside Vdefs/mean blood flow of the lung).

Countries

United States