Banca de DEFESA: LAYANA MARQUES DE OLIVEIRA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : LAYANA MARQUES DE OLIVEIRA
DATE: 19/11/2021
TIME: 14:00
LOCAL: videoconferência
TITLE:

Respiratory Muscle Changes in Duchenne Muscular Dystrophy: its consequences on the clinical presentation of the disease

KEY WORDS:

Duchenne muscular dystrophy, thoracoabdominal asynchrony, respiratory muscles.

PAGES: 120
BIG AREA: Ciências da Saúde
AREA: Fisioterapia e Terapia Ocupacional
SUMMARY:

Abstract Introduction: Duchenne muscular dystrophy (DMD) results in progressive weakness and loss of all striated muscles, including the respiratory muscles, with consequences for walking, in addition to breathing difficulties, as the main cause of death. In the last decades, the survival of patients with DMD has increased thanks to a more comprehensive therapeutic approach, mainly with measures for the assessment and early management of pulmonary complications. However, there are still gaps in the understanding of how changes in respiratory muscles and body postures can influence thoracoabdominal synchrony and maximum nasal respiratory pressures in this population and how the introduction of new non-invasive clinical measures can assist in the management of these patients. Objective: The main objective of this thesis is to better understand the changes in respiratory muscle strength in Duchenne Muscular Dystrophy and its consequences on the clinical course of the disease. For this, three objectives were set: 1) Assess how body position influences thoracoabdominal asynchrony and paradoxical inspiratory movement during quiet breathing and cough in DMD; 2) Assess how the change in body positioning during the assessment of maximum nasal pressures can affect blood pressure values, relaxation rates, muscle contractile properties, as well as modify electromyographic muscle activation in DMD; 3) Monitor the clinical evolution of respiratory and motor function, in addition to the relaxation rates and contractile properties of inspiratory muscles in DMD over a 6-month follow-up. Methods: For study 1, assessed 14 DMD subjects and 12 controls using Optoelectronic Plethysmography (OEP) during quite breathing (QB) and spontaneous cough in 3 positions: supine, supine with headrest raised at 45° (45°), and sitting with back support at 80° (80°). The TAA was assessed using phase angle (θ) between upper (RCp) and lower rib cage (RCa) and abdomen (AB), as well as the percentage of inspiratory time the RCp (IPRCp), RCa (IPRCa) and AB (IPAB) moved in opposite directions. In study 2, the relaxation rates and contraction properties of the inspiratory and expiratory muscles were extracted from the sniff nasal inspiratory pressure (SNIP) and reverse sniff nasal expiratory pressure (RSNEP) curves, performed non-invasively in 9 patients with DMD in different positions. Study 3 is a 6-month study of relaxation rates and contraction properties of the inspiratory muscles were extracted from SNIP in 22 DMD subjects. Results: 1) During cough, DMD group showed higher RCp and RCa θ (p<.05), RCp and AB θ (p<.05) in supine and 45° positions, and higher RCp and Rca θ (p=.006) only in supine position compared with controls. Regarding the intragroup analysis, during cough, DMD group presented higher RCp and AB θ (p=.02) and RCa and AB θ (p=.002) in supine and higher RCa and AB θ (p=.002) in 45° position when compared to 80°. ROC curve analyzes were able to discriminate TAA between controls and DMD in RCa and AB θ in supine position [AUC: 0.81, sensibility: 78.6% and specificity: 91.7%, p=0.001]. 2) During SNIP and RSNEP, there is no difference in pressure, relaxation rates, and contraction properties in different positions. However, subjects with DMD exhibited higher activation in EI just during the SNIP test. 3) When compared to healthy subjects, patients with DMD present a lower (p<.005) maximum relaxation rate (MRR) and a greater tau (τ) and half‐relaxation time (½ RT) in baseline and after 6 months. The results of the ROC curves showed that MRR, τ, ½ RT and SNIP (%pred) parameters were significantly able to discriminate between DMD and controls in baseline and after 6 months. Conclusions: During cough, subjects with DMD yields TAA with insufficient deflation of chest wall compartments and rib cage distortion, by non-invasive assessment. In addition, the position no affects the SNIP, RSNEP, and either relaxation rates and contraction properties of SNIP and RSNEP curve in different positions. Still, it is possible to discriminate altered parameters of relaxation rates and SNIP after 6 months in individuals with DMD concerning healthy subjects. These new non-invasive measurement techniques, such as the assessment of thoracoabdominal asynchrony, and the weakness of inspiratory and expiratory muscles presented in this study may help us in the early clinical management of this population. Key words: Duchenne muscular dystrophy, thoracoabdominal asynchrony, respiratory muscles.

BANKING MEMBERS:
Externo à Instituição - ANTONIO JOSÉ SARMENTO DA NÓBREGA
Externo à Instituição - FERNANDO AUGUSTO LAVEZZO DIAS - UFPR
Externa ao Programa - 2211023 - ILLIA NADINNE DANTAS FLORENTINO LIMA
Externa ao Programa - 2211046 - LUCIEN PERONI GUALDI
Presidente - 5566309 - VANESSA REGIANE RESQUETI FREGONEZI