Aplicabilidade da técnica de oscilações forçadas modificada na avaliação da função pulmonar de crianças e adolescentes com bronquiolite obliterante

Abstract

Introduction: Bronchiolitis obliterans post infecction (PIBO) is a chronic obstructive pulmonary disease characterized by obliteration of the distal airways caused by fibrosis and scarring of lung tissues. Assessment of pulmonary function, and particularly the demonstration of reversibility of obstruction, may assist in the diagnosis and evaluation of respiratory system impairment. The forced oscillation technique (FOT) is a functional evaluation method with a high success rate in situations of poor patient collaboration and describes mechanical properties of the respiratory system that are not evidenced in spirometry. Objective: To evaluate the accuracy of spectral FOT and within-breath for the detection of BO. Methods: Cross-sectional study. The sample was selected for convenience, being composed of children and adolescents with BO and controls, aged between 4 and 19 years. Anthropometry, clinical history and measures of respiratory impedance were obtained in all participants. Spirometry was performed in the BO group. Results: 16 subjects with BO and 32 healthy individuals were recruited. Patients with BP had a more negative response (p=0.001), with more negative inertance (p=0.001) and a higher frequency of resonance (p=0.029) when compared to patients with BP (X6hz, 8hz, 10hz, p <0.05) controls. The variables of the intra-breath analysis with greater sensitivity to differentiate the BO subjects of the controls were XmédiaE, XmédiaI and XeE. Conclusions: The results showed that the individuals with BO present significantly more negative reactance in the low frequencies by the within-breath method, with consequent elevation of fRes.