Oscillation Mechanics of the Respiratory System in Never-smoking Patients With Silicosis
|ClinicalTrials.gov Identifier: NCT01725971|
Recruitment Status : Completed
First Posted : November 14, 2012
Last Update Posted : October 23, 2014
Silicosis is a chronic and incurable occupational disease that can progress independent of the end of exposure. Recent works suggest that the Forced Oscillation Technique (FOT) may help to improve our understanding of the changes in lung mechanics, as well as in the detection of these changes.
Objectives: Analyze the effects of airway obstruction in silicosis on the respiratory impedance and evaluated the diagnostic use of the FOT in these patients. For this, the investigators used spirometry to classify airway obstruction, which resulted in four categories: control, patients with normal exam, mild obstruction, and moderate-to-severe obstruction. Resistive data were interpreted using the zero-intercept resistance (R0), the resistance at 4 Hz (Rrs4) and the mean resistance (Rm). The investigators also analyzed the mean reactance (Xm) and the dynamic compliance (Crs,dyn). The total mechanical load was evaluated using the absolute value of the respiratory impedance (Z4Hz). The diagnostic potential was evaluated by investigating the area under the receiver operating characteristic curve (AUC).
|Condition or disease|
|Study Type :||Observational|
|Actual Enrollment :||67 participants|
|Official Title:||The Use of Forced Oscillation Technique in the Analysis of Respiratory System in Never-smoking Patients With Silicosis:Pathophysiological Study and Evaluation of Diagnostic Accuracy|
|Study Start Date :||July 2010|
|Primary Completion Date :||December 2012|
|Study Completion Date :||June 2013|
Group of nonsmokers individuals without respiratory disease.
subjects with silicosis , but with normal spirometric data
subjects with silicosis with mild obstruction in spirometric data
moderate to severe obstruction
subjects with silicosis with moderate to severe obstruction in spirometric data
- spirometric [ Time Frame: 1 day ]Spirometry was used to classify airway obstruction, which resulted in four categories: control (n=21), patients with normal exam (n=12), mild obstruction (n=22), and moderate-to-severe obstruction (n=12).
- Forced Oscillation technique [ Time Frame: 1 day ]In the analysis of the forced oscillation technique was used the following data: Resistive data were interpreted using the zero-intercept resistance (R0), the resistance at 4 Hz (Rrs4) and the mean resistance (Rm). The researchers also analyzed the mean reactance (Xm) and the dynamic compliance (Crs,dyn). The total mechanical load was evaluated using the absolute value of the respiratory impedance (Z4Hz).
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01725971
|Laboratório de Instrumentação Biomédica|
|Rio de janeiro, Brazil, 21550-013|