Oscillation Mechanics of the Respiratory System in Never-smoking Patients With Silicosis

Completed

• Conditions: Silicosis

• Registration Number: NCT01725971
• Lead Sponsor: Rio de Janeiro State University

Brief Summary

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).

Detailed Description

Not available

Study Timeline

• Study Start: 2010-07
• Study First Submitted: 2012-10-30
• Study First Submitted QC: 2012-11-08
• Study First Posted: 2012-11-14
• Primary Completion: 2012-12
• Study Completion: 2013-06
• Status Verified: 2014-10
• Last Update Submitted: 2014-10-21
• Last Update Posted: 2014-10-23

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 67

Inclusion Criteria

• • Volunteers with silicosis for Patients Group;

  • Volunteers without any respiratory disease for the control group.

Exclusion Criteria

• Smokers

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
spirometric	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	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).

Trial Locations

Locations (1)

Laboratório de Instrumentação Biomédica; 🇧🇷 Rio de janeiro, Brazil