Oscilometria respiratória e análises funcionais em pacientes com escoliose idiopática

Abstract

Scoliosis is a condition that affects the vertebral column and causes thorax rotation and trunk distortion. Juvenile idiopathic scoliosis is diagnosed at the beginning of puberty and can progress until the young stage. Depending on the angle of the spine curvature, these patients may present pulmonary complications with the possibility of also presenting cardiac complications later, making surgical intervention necessary to correct the deformity. In the literature, besides classical spirometry, only a few respiratory mechanics assessment methods were added to the propaedeutic arsenal. Several studies have been focusing on new tests that complement the information provided by classic tests, and tests that require less cooperation and effort from the patient or that can be performed under adverse conditions. Respiratory oscillometry, also known as the Forced Oscillation Technique (FOT) has been assuming relevance as a tool in pulmonary function laboratories because of its potential to improve diagnosis and monitor the treatments of respiratory diseases, but additional studies are needed in this area. Previous studies demonstrated that the parameters derived from FOT enable a detailed analysis of the respiratory system of patients with airflow obstruction and restrictive respiratory disease, contributing to a better pathophysiological understanding of these abnormalities. However, only one study showed evidence that FOT can contribute to the differential diagnosis in individuals with idiopathic scoliosis. This work aims to investigate the potential of FOT in the evaluation of respiratory mechanics in patients with scoliosis and its association with physical performance. This is a controlled cross-sectional study, in which volunteers were divided into 2 groups: control and scoliosis, with a total of 64 individuals (32 in each group). Volunteers were submitted to pulmonary function tests, FOT, and 6-minute walk test (6MWT). The scoliosis group, when compared with the control, presented altered spirometry and plethysmography values. In the FOT, increases were observed in the resistive parameters R0 (p<0,001), R4 (p<0,01), R12 (p<0,0001), R20 (p<0,01), and Rm (p< 0,001). No significant changes were observed in the parameters R4-R20 and S (both with p=0,31). In the reactive parameters, reductions were observed in Xm (p<0,001), Cdin (p<0,001), fr (p<0,001), and Ax (p<0,001). The Z4Hz parameter also showed an increase (p<0,01). Functional capacity was reduced with the 6MWT (p≤0,001). These results demonstrate new information on respiratory mechanics in scoliosis, with important changes that are consistent with the pathophysiology in spirometry, plethysmography, FOT, and TC6m tests. It confirms that the method has the potential for the functional evaluation of patients with scoliosis