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Updated: Jul 17, 2026

Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults
Published on: February 9, 2022
Using the forced oscillation technique to evaluate respiratory resistance in individuals with silicosis
Jayme Alves de Mesquita Júnior1, Agnaldo José Lopes, José Manoel Jansen
1Laboratory of Biomedical Instrumentation, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil.
Objective:
To evaluate the resistance values obtained through the use of the forced oscillation technique in patients with varying degrees of airway obstruction resulting from silicosis.
Methods:
A total of 40 never-smoking volunteers were analyzed: 10 were healthy subjects with no history of pulmonary disease or silica exposure, and 30 had silicosis. The forced oscillation technique was used to examine the subjects, and spirometry was used as a reference in order to classify the obstruction by degree. This classification resulted in five groups: control (n = 10); normal exam, composed of individuals diagnosed clinically and radiologically with silicosis but presenting normal spirometry results (n = 7); mild obstruction (n = 10); moderate obstruction (n = 8); and severe obstruction (n = 5).
Results:
The reduction observed in the spirometric values corresponded to a significant increase in the total respiratory resistance (p < 0.001), as well as in airway resistance (p < 0.003). A significant reduction in ventilation homogeneity was also observed (p < 0.004).
Conclusion:
In individuals with silicosis, the additional respiratory resistance-related data obtained through the use of the forced oscillation technique can complement spirometric data. Therefore, the forced oscillation technique presents great potential for the analysis of such patients.
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