Efeito da ventilação não-invasiva em repouso e durante o exercício físico nas respostas cardiovasculares e no desempenho físico em indivíduos saudáveis

• Autor(a) principal: Gonçalves, Thiago Rodrigues
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal Fluminense (RIUFF)
• Texto Completo: https://app.uff.br/riuff/handle/1/19667
• topic: Trabalhos dos músculos respiratórios; Ventilação não-invasiva; Exercício físico; Desempenho físico; CIÊNCIAS CARDIOVASCULARES; MEDICINA; Respiração artificial; Doenças cardiovasculares; Desempenho atlético; Respiratory muscle work; Non-invasive ventilation; Exercise; Performance; CNPQ::CIENCIAS DA SAUDE::MEDICINA::CLINICA MEDICA::CARDIOLOGIA

Background: During high intensity physical exercise the respiratory muscles work (RMW) induce the competition for blood flow between the respiratory and locomotors muscles, limiting the performance. However, the use of non-invasive ventilation (NIV) during the intense exercise may facilitate the RMW and increase the tolerance to fatigue in healthy individuals. Our objective was to investigate the effects of NIV on cardiovascular responses in rest and during the exercise in the exercise time to exhaustion (TLIM) and in the rate perception effort (RPE) in healthy individuals. Methods: The study was divided for NIV applied during rest and exercise. In the rest condition the inspiratory pressure (IPAP) was 20cmH2O and expiratory pressure (EPAP) = 15cmH2O (continuous positive airway pressure, CPAP) with n = 7, 24 ± 2 years. In a second condition IPAP was 20cmH2O and EPAP = 0cmH2O (inspiratory pressure support, IPS) with n = 6, 24 ± 2 years and both respiratory rate of 0.25Hz. The cardiac output (CO) was verified by infra-red photopletismograph (FPI) and analyzed the spontaneous baroreflex sensivity (BRS, ms/mmHg) by alfa index of HF (&#945;-HF). During exercise, 10 men volunteers (24 ± 3 years, VO2max = 41.4 ± 7.8 mL.kg.-1min-1) performed four exercises of constant load, divided in adaptation and experimental exercises, with IPS and without IPS (Control) to 80%VO2max to exhaustion with randomized for each situation. The RPE was determined by Borg scale (0-10), the TLIM and the CO by FPI. Results: We obtained in rest for CPAP: CO (14%) and the BRS decreased (43%) in relation to rest, p < 0.05. For IPS, the CO and BRS did not alter in relation to rest (p > 0.05). In exercise, the IPS increased the TLIM (633.8 ± 105.8 vs 556.3 ± 64.1s; p < 0.05) and decreased the RPE for dyspnea (6.5 ± 1.7 vs 7.9 ± 2.1) and locomotor muscles (8.2 ± 1.9 vs 9.2 ± 1.7, p < 0.05). The CO did not alter (IPS = 14.0 ± 4.7 vs Control =15.5 ± 5.3 L.min-1, p > 0.05). Conclusion: The use of NIV in rest decreased the baroreflex sensitivity possibly due to fall of cardiac output and in exercise increased the performance without presenting cardiovascular alterations in relation to control situation