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

Rio de Janeiro State University67 enrolled

Overview

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).

Study Type

OBSERVATIONAL

Enrollment

Conditions

Silicosis

Eligibility

Sex: ALLMin age: 18 YearsMax age: 90 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * • Volunteers with silicosis for Patients Group; * Volunteers without any respiratory disease for the control group. Exclusion Criteria: * Smokers

Locations (1)

Outcomes

Primary Outcomes

spirometric

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).

Time frame: 1 day

Forced Oscillation technique

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).

Time frame: 1 day