Efeitos de dispositivos de reexpansão pulmonar na atividade eletromiográfica de músculos respiratórios em sujeitos pós AVC

Abstract

Background: Stroke presents as the primary clinical manifestation the hemiplegia or hemiparesis. In addition, there is respiratory muscle strength decreasing (expressed as maximal inspiratory and expiratory pressure - MIP and MEP), attenuation of electromyographic activity, elevation of the diaphragmatic dome, and reduction of thoracic expansion on the paretic side. These disorders culminate in a restrictive breathing pattern. Therefore, devices that help maintain lung volumes can facilitate the preservation of airway permeability and respiratory muscle activity. Objective: To compare the activation of different respiratory muscles during the use of breathing devices in stroke patients through the analysis of electromyographic activity level of 4 respiratory muscles: parasternal (PARA), scalene (SCL), sternocleidomastoid (SCM) and rectus abdominis (RA). Methodology: This is a crossover study, which evaluates 12 stroke cases according to anthropometric measurements, clinical history, pulmonary function, and respiratory muscle strength. The electromyographic activity of SCM, SCL, PARA and RA muscles was analyzed by surface electromyography during volume-oriented incentive spirometry (VIS), positive expiratory pressure (PEP), and association of both devices (VIS + PEP). Results: We included 12 individuals (5W) after hemorrhagic or ischemic stroke, with mean time after injury of 4.25 ± 2.64 (years), mean age of 52.1 ± 11.59 (years), and BMI of 26 ± 3. 25 (kg/m²). We found respiratory muscle strength lower than predicted for each individual, MIP 64.13 ± 20.09 (% pred), and MEP 74.02 ± 20.04 (% pred). However, they presented normal spirometric values according to prediction (FEV1 = 81.92 ± 15.83 (% pred) and FEV1/FVC ratio = 90.78 ± 15.28). During the use of VIS and VIS + PEP, the SCM and SCL muscles showed higher activity when compared with PEP. Already in the comparison between VIS and VIS + PEP, there was no significant difference in the activation of these muscles. For PARA and RA muscles, there was no significant difference in the activation in any of the recommended devices. For all muscles analyzed, p <0.05 was adopted. Conclusion: There was no difference in the electrical activity level of the SCM and SCL muscles with VIS alone or in association with PEP.