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Updated: Jun 5, 2026

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics
Published on: April 19, 2024
Flutter valve improves respiratory mechanics and sputum production in patients with bronchiectasis
Pedro H S Figueiredo1, Walter A Zin, Fernando S Guimarães
1Curso de Graduação em Fisioterapia, Pontifícia Universidade Católica de Minas Gerais, Brazil.
Background And Purpose:
Although the application of airway clearance techniques is considered an important component in the treatment of several obstructive pulmonary diseases, there is no scientific evidence supporting the use of Flutter Valve™ in the management of patients with bronchiectasis. Moreover, the consequences of respiratory physiotherapy techniques on respiratory mechanics have not been fully studied. Therefore, we investigated the acute, short-term effects of Flutter Valve™ on respiratory mechanics and sputum production in bronchiectatic patients.
Methods:
EIGHT patients were evaluated in a randomized, blinded, cross-over trial. Impedance at 5 Hz (R5), resistance as a function of oscillation frequency (dR/dF), reactance at 5 Hz (X5), resonant frequency (f(0) ) and integral of reactance between 5 Hz and resonant frequency (AX) were recorded.
Results:
Flutter Valve™ cleared 8.4 mL more secretions than the Sham Flutter intervention (95% confidence interval [95% CI], 3.4-13.4). There was a higher percentage decrease in R5 (-11.2%; 95% CI, -4.4 to -18.2), dR/dF (-20.8%; 95% CI, -32.4 to -9) and AX (-7.8%; 95% CI, -11.9 to -3.7) under Flutter Valve™. X5 and f(0) variation did not differ between interventions.
Conclusions:
Flutter Valve™ increases sputum removal during treatment and diminishes total and peripheral airway resistance in hypersecretive patients with bronchiectasis. Impulse oscillometry is a user-friendly tool to evaluate the effects of airway clearance techniques on respiratory mechanics.
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