Ignite Creation Date:
2024-05-05 @ 11:49 AM
Last Modification Date:
2024-10-26 @ 9:14 AM
Study NCT ID:
NCT00145990
Status:
COMPLETED
Last Update Posted:
2012-03-05
First Post:
2005-09-01
Brief Title:
The Impact of Dosimeter on Measurement of Airway Responsiveness to Methacholine
Sponsor:
University of Florida
Organization:
University of Florida
Study Overview
Official Title:
None
Status:
COMPLETED
Status Verified Date:
2012-03
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
To determine whether there is a difference in two different breathing tests used to detect asthma Hypothesis The Digidoser delivers less methacholine to the airways and will result in a higher PC20 than the value determined by the Rosenthal Dosimeter
Detailed Description:
Bronchoprovocation with methacholine is used to confirm the diagnosis of asthma The procedure involves inhaling methacholine through a nebulizer attached to a dosimeter that delivers a precise volume of methacholine The endpoint of the test is the provocational concentration that produces a 20 decrease in FEV1 PC20 To standardize the procedure the American Thoracic Society ATS recommends that the nebulizer output be calibrated to deliver an output of 09 009 mLmin
The Rosenthal Dosimeter and the KoKo Digidoser are two commonly used dosimeters In an attempt to follow the ATS guideline we discovered that the nebulizer output was lower with the KoKo Digidoser and could not be calibrated However it is unclear whether the apparent lower output is a result of the Digidoser delivering less solution or that the ATS method of determining output is not applicable to this dosimeter To answer this question we propose to determine the methacholine PC20 in subjects with asthma using the two dosimeters It is our hypothesis that the Digidoser delivers less methacholine and thus will produce a higher PC20 than the Rosenthal Dosimeter
Twelve nonsmoking subjects with mild asthma will be selected on the basis of 18 years of age a baseline FEV1 of 60 predicted and a screening PC20 of 8mgml Subjects will be randomized to perform a methacholine challenge with the Digidoser and the Rosenthal Dosimeter on two different days in an unblinded crossover manner The geometric mean PC20 with each dosimeter will be compared with a paired t test The results of this study will indicate whether the Digidoser has the potential of causing false negative test results or whether the ATS method of determining output should not be used with this dosimeter
The Rosenthal Dosimeter and the KoKo Digidoser are two commonly used dosimeters In an attempt to follow the ATS guideline we discovered that the nebulizer output was lower with the KoKo Digidoser and could not be calibrated However it is unclear whether the apparent lower output is a result of the Digidoser delivering less solution or that the ATS method of determining output is not applicable to this dosimeter To answer this question we propose to determine the methacholine PC20 in subjects with asthma using the two dosimeters It is our hypothesis that the Digidoser delivers less methacholine and thus will produce a higher PC20 than the Rosenthal Dosimeter
Twelve nonsmoking subjects with mild asthma will be selected on the basis of 18 years of age a baseline FEV1 of 60 predicted and a screening PC20 of 8mgml Subjects will be randomized to perform a methacholine challenge with the Digidoser and the Rosenthal Dosimeter on two different days in an unblinded crossover manner The geometric mean PC20 with each dosimeter will be compared with a paired t test The results of this study will indicate whether the Digidoser has the potential of causing false negative test results or whether the ATS method of determining output should not be used with this dosimeter
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None