The presented thesis is focused on the influence of postural stability changes on respiratory muscle strength. The aim of this thesis was to determinate whether the respiratory muscle strength will change during the increased demands on postural stability, and if so, then how exactly. The theoretical part summarized the findings about the diaphragm and its postural stabilizing function, about the connection between breathing and postural control as well as about the influence of body position on respiratory muscle strength. In the practical part of the thesis, the values of the maximal respiratory mouth pressures were measured (PI max and PE max) on 21 healthy subjects ranging from 20 to 26 years of age using the spirometer in three postural situations - standing, standing on the balance surface and standing on the balance surface with no visual control. Throughout the whole group, there were no significant statistical differences ( p ≥ 0,05 ) in the outcome values of the measured postural situations. Two trends were observed in the changes of values of PI max and PE max. During the increased demands for postural stability the value of PI max was higher for 29% and lower for 71% of the measured individuals. The value of PE max was higher for 33% and lower for 67% of the measured individuals. This...

Introdução: A aplicação da pressão positiva expiratória (EPAP) em pacientes com DPOC durante o exercício pode reduzir a hiperinflação dinâmica (HD) e consequentemente a dispneia, enquanto, por outro lado, pode aumentar o trabalho resistivo da respiração. O objetivo do presente estudo foi avaliar os efeitos de duas intensidades de EPAP sobre a capacidade inspiratória, dispneia e tolerância ao exercício em pacientes com DPOC moderada a muito grave. Métodos: Estudo transversal, experimental, de 4 visitas. Na visita 1, os participantes realizaram um teste de exercício cardiopulmonar incremental limitados por sintomas (TECP). Nas visitas 2-4, com pelo menos 48 horas de intervalo, em ordem aleatória, eles realizaram TECP com carga constante (TECPct; 75% da carga de pico) sem EPAP, EPAP com 5cmH2O (EPAP5), ou EPAP com 10cmH2O (EPAP10). Resultados: O estudo incluiu 15 participantes não hipoxêmicos com DPOC moderada a muito grave (média de VEF1= 35,3 ± 10,9% do previsto). As intensidades sucessivas de EPAP durante o TECPct tenderam a causar uma redução progressiva da tolerância ao exercício (p=0,11). Destaca-se que 10 dos 15 pacientes apresentaram menor duração de exercício quando o EPAP10 foi comparado ao teste sem EPAP (-151 ± 105s, p <0,01 ou -41 ± 26%). Além disso, observou-se com EPAP (p <0,05) uma redução significativa da ventilação minuto, as custas de uma restrição na expansão do volume corrente. Por fim, a sensação de dispneia e medidas seriadas da capacidade inspiratória durante o exercício não foram diferentes entre as três intervenções. Conclusão: Níveis progressivos de EPAP durante o exercício tendem a causar uma redução progressiva na tolerância ao exercício em pacientes com DPOC sem melhora na dispneia e HD. / Introduction: The application of expiratory positive aiway pressure (EPAP) in COPD patients during exercise may reduce dynamic hyperinflation (DH), and consequently dyspnea, while, on the other hand, can increase the resistive work of breathing. Therefore, the objective of the current study was to evaluate the effects of two intensities of EPAP on inspiratory capacity, dyspnea and exercise tolerance in patients with moderate to very-severe COPD. Methods: Cross-sectional, experimental, 4-visit study. In the Visit 1, participants performed symptom-limited cycling incremental cardiopulmonary exercise test (CPET). In Visits 2-4, at least 48hrs apart, in a randomized order, they performed constant CPET (ctCPET) without EPAP, EPAP with 5cmH2O (EPAP5), or EPAP with 10cmH2O (EPAP10). Results: The study included 15 non-hypoxemic subjects ranging from moderate-to-very-severe COPD (mean FEV1=35.3 ± 10.9% of predicted). Successive intensities of EPAP during ctCPET tended to cause a progressive reduction in exercise tolerance (p=0.11). Of note, 10 of 15 presented shorter exercise duration when EPAP10 was compared to the test without EPAP (-151±105s, p<0.01 or -41±26%). Moreover, significant constraint to minute-ventilation, at expenses of limited tidal volume expansion, was observed with EPAP (p<0.05). Finally, dyspnea sensation and IC measurements were similar during exercise among the interventions. Conclusion: Progressive levels of EPAP during exercise tented to cause a progressive reduction in exercise tolerance in COPD patients without improvement in exercise dyspnea and DH.

INTRODUÇÃO: Treinamento muscular inspiratório (TMI) tem se mostrado capaz de aumentar a espessura diafragmática. Sabe-se que o diafragma crural age como um esfincter externo do esfíncter inferior do esôfago (EIE), mas é desconhecido se pacientes com hipotonia do EIE se beneficiariam do TMI, a fim de aumentarem a pressão respiratória média (PRM), consequentemente havendo melhora dos sintomas de refluxo gastroesofágico. OBJETIVO: Determinar o resultado dos efeitos do TMI nas pressões respiratória média nos pacientes com doença do refluxo gastroesofágico e seu efeito no tônus do esfíncter inferior do esôfago e compará-los com o grupo controle. MÉTODOS: Vinte pacientes foram incluídos no grupo caso e nove no grupo controle. Todos pacientes tinham a pressão expiratória máxima (PEM) entre cinco e 10mmHg e foram submetidos à manometria esofágica e teste de função pulmonar antes e após oito semanas de treinamento utilizando o threshold IMT (Respironics, Cedar Grove, NJ) duas vezes ao dia. A medida da pressão inspiratória máxima (Pimax) foi aferida a cada duas semanas. O grupo caso teve o threshold IMT ajustado progressivamente, a cada quinze dias, sempre a 30% da nova Pimax. O grupo controle realizou o treinamento com o mesmo aparelho, sob uma pressão constante de 7cmH2O. O nível de significância estatística foi estabelecido a 5% (p £ 0,05). RESULTADOS: A média de idade do grupo caso foi 50,1 ± 18 e no grupo controle de 51,3± 11 anos. Após oito semanas de treinamento utilizando o threshold IMT houve uma melhora na PRM em 15 (75%) pacientes, representando um ganho médio de 46,6% (p<0,01), enquanto no grupo controle, seis (66%) pacientes obtiveram um aumento médio de 26,2% (p<0,01). Não houve diferença estatisticamente significante entre os grupos (p= 0,507). A PEM também aumentou quando comparada com a inicial (p<0,01), mas não diferiu entre os grupos (p= 0,727). Observou-se uma melhora na Pimax no grupo 1 (40% versus 19,6%). Houve um aumento na pressão expiratória máxima (Pemax) em ambos os grupos após as oito semanas de IMT (p< 0,05). CONCLUSÕES: O treinamento muscular inspiratório aumentou as pressões respiratória média e expiratória máxima ao longo das oito semanas em ambos os grupos. Não houve diferença com significância estatística entre os grupos sugerindo que o aumento na pressão do esfíncter inferior do esôfago ocorre independentemente da resistência aplicada ao threshold IMT. Mais estudos são necessários para determinar o impacto clínico desse aumento pressórico e confirmar ou afastar a manutenção dessas pressões a longo prazo / INTRODUCTION: Inspiratory muscle training (IMT) has been shown to increase diaphragm thickness. It is known that the diaphragmatic crural fibers act as an external LES, but it is unknown if patients with hypotensive lower esophageal sphincter (LES) would benefit from IMT increasing the mid-respiratory pressure (MRP), and as such relieving gastroesophageal reflux symptoms. AIM: Evaluate the effect of inspiratory muscle training on MRP in patients with gastroesophageal reflux disease and hypotensive LES and compare it with the control group. PATIENTS AND METHODS: Twenty consecutive patients (progressive loading group) and 9 controls (sham group) were included. All of them had end expiratory pressure (EEP) between 5 and 10mmHg and underwent esophageal manometry and pulmonary function tests before and after 8 weeks of training using a threshold IMT (Respironics, Cedar Grove, NJ) twice daily. The maximal inspiratory pressure (Pimax) measurement was repeated each 2 weeks. The progressive loading group had their threshold IMT set at 30% of their new Pimax. Sham-treated patients (same device but minimal resistance to the air flow) had their threshold set at 7cmH2O and it was maintained constant during the period. The significance level was set at 5% (p £ 0.05). RESULTS: The mean age of progressive loading group was 50.1 ± 11.3 years and sham group was 51.3± 6.3. Following eight weeks of training using a threshold IMT there was an increase in MRP in 15 (75%) patients, representing an average gain of 46.6% (p<0.01), while in the sham group, six (66%) patients had their MRP raised with mean increase of 26.2% (p< 0.01). There was no significant difference between the groups (p= 0.507). EEP also increased when compared with before measured (p<0.01), but did not differ between groups (p= 0.727). It has also been observed an improvement in the Pimax in progressive loading group (40% versus 19.6%). It was observed a gain in the maximal expiratory pressure (Pemax) as well in both groups after the 8-week program of IMT (p< 0.05). CONCLUSION: Inspiratory muscle training increased MRP and EEP in patients of active and sham-treated group after an 8-week program. There was no significant statistical difference between groups suggesting that the increase in pressure at LES occurs regardless to the resistance loading of threshold IMT. Extended follow-up is necessary to document the long-term benefits of such improvements

The primary aim of this thesis was to develop a better understanding of the physiology and perceptual responses associated with the performance of continuous (CE) and intermittent exercise (IE) in patients with moderate chronic obstructive pulmonary disease (COPD). A secondary aim was to examine factors that could potentially limit exercise tolerance in COPD patients, particularly in relation to the dynamics of the cardiovascular system and muscle metabolism. The results of the four studies conducted to achieve these aims are presented in this thesis. In Study 1, the physiological, metabolic and perceptual responses to an acute bout of IE and CE were examined in 10 individuals with moderate COPD. Each subject completed an incremental exercise test to exhaustion on a cycle ergometer. Subjects then performed IE (1 min exercise: 1 min rest ratio) and CE tests at 70% of peak power in random order on separate days. Gas exchange, heart rate, plasma lactate concentration, ratings of breathlessness, inspiratory capacity and the total amount of work completed were measured during each exercise test. Subjects were able to complete a significantly greater amount of work during IE (71 ± 32 kJ) compared with CE (31 ± 24 kJ). Intermittent exercise was associated with significantly lower values for oxygen uptake, expired ventilation and plasma lactate concentration when compared with CE. Subjects also reported a significantly lower rating of breathlessness during IE compared to CE. The degree of dynamic lung hyperinflation (change in end-expiratory lung volume) was lower during IE (0.23 ± 0.07 L) than during CE (0.52 ± 0.13 L). The results suggest that IE may be superior to CE as a mode of training for patients with COPD. The greater amount of total work performed and the lower measured physiological responses attained with intermittent exercise could potentially allow greater training adaptations to be achieved in individuals with more limited lung function. The purpose of Study 2 was to compare the adaptations to 8 wk of supervised intermittent and continuous cycle ergometry training, performed at the same relative intensity and matched for total work completed, in patients with COPD. Nineteen subjects with moderate COPD were stratified according to age, gender, and pulmonary function, and then randomly assigned to either an IE (1 min exercise: 1 min rest ratio) or CE training group. Subjects trained 3 d per week for 8 wk and completed 30 min of exercise. Initial training intensity, i.e., the power output applied during the CE bouts and during the exercise interval of the IE bouts, was determined as 50% of the peak power output achieved during incremental exercise and was increased by 5% each week after 2 wk of training. The total amount of work performed was not significantly different (P=0.74) between the CE (750 ± 90 kJ) and IE (707 ± 92 kJ) groups. The subjects who performed IE (N=9) experienced significantly lower levels of perceived breathlessness and lower limb fatigue during the exercise-training bouts than the group who performed CE (N=10). However, exercise capacity (peak oxygen uptake) and exercise tolerance (peak power output and 6-min walk distance) improved to a similar extent in both training groups. During submaximal constant-load exercise, the improved (faster) phase II oxygen uptake kinetic response with training was independent of exercise mode. Furthermore, training-induced reductions in submaximal exercise heart rate, carbon dioxide output, expired ventilation and blood lactate concentrations were not different between the two training modes. Exercise training also resulted in an equivalent reduction for both training modes in the degree of dynamic hyperinflation observed during incremental exercise. Thus, when total work performed and relative intensity were the same for both training modes, 8 wk of CE or IE training resulted in similar functional improvements and physiological adaptations in patients with moderate COPD. Study 3 examined the relationship between exercise capacity (peak oxygen uptake) and lower limb vasodilatory capacity in 9 patients with moderate COPD and 9 healthy age-matched control subjects. While peak oxygen uptake was significantly lower in the COPD patients (15.8 ± 3.5 mL·min-1·kg-1) compared to the control subjects (25.2 ± 3.5 mL·kg-1·min-1), there were no significant differences between groups in peak calf blood flow or peak calf conductance measured 7 s post-ischemia. Peak oxygen uptake was significantly correlated with peak calf blood flow and peak conductance in the control group, whereas there was no significant relationship found between these variables in the COPD group. However, the rate of decay in blood flow following ischemia was significantly slower (p less than 0.05) for the COPD group (-0.036 ± 0.005 mL·100 mL-1·min-1·s-1) when compared to the control group (-0.048 ± 0.015 mL·100 mL-1·min-1·s-1). The results of this study suggest that the lower peak exercise capacity in patients with moderate COPD is not related to a loss in leg vasodilatory capacity. Study 4 examined the dynamics of oxygen uptake kinetics during high-intensity constant-load cycling performed at 70% of the peak power attained during an incremental exercise test in 7 patients with moderate COPD and 7 healthy age-matched controls. The time constant of the primary component (phase II) of oxygen uptake was significantly slower in the COPD patients (82 ± 8 s) when compared to healthy control subjects (44 ± 4 s). Moreover, the oxygen cost per unit increment in power output for the primary component and the overall response were significantly higher in patients with COPD than in healthy control subjects. A slow component was observed in 5 of the 7 patients with COPD (49 ± 11 mL·min-1), whereas all of the control subjects demonstrated a slow component of oxygen uptake (213 ± 35 mL·min-1). The slow component comprised a significantly greater proportion of the total oxygen uptake response in the healthy control group (18 ± 2%) than in the COPD group (10 ± 2%). In the COPD patients, the slow component amplitude was significantly correlated with the decrease in inspiratory capacity (r = -0.88, P less than 0.05; N=5), indicating that the magnitude of the slow component was larger in individuals who experienced a greater degree of dynamic hyperinflation. This study demonstrated that most patients with moderate COPD are able to exercise at intensities high enough to elicit a slow component of oxygen uptake during constant-load exercise. The significant correlation observed between the slow component amplitude and the degree of dynamic hyperinflation suggests that the work of breathing may contribute to the slow component in patients with COPD.

Introdução: Pacientes com hipertensão pulmonar (HP) além de apresentar redução da capacidade funcional, da qualidade de vida e da sobrevida, apresentam fraqueza dos músculos respiratórios, o que pode contribuir para o aumento dos sintomas de fadiga e dispneia. Objetivos: Verificar o efeito do treinamento muscular inspiratório (TMI) sobre a capacidade funcional, a qualidade de vida, a força muscular respiratória, pressão sistólica da artéria pulmonar, a função pulmonar e o nível de atividade física de pacientes com HP. Métodos: Doze pacientes com HP foram randomizados em um grupo controle (n=7) e um grupo TMI (n=5). O protocolo do TMI foi realizado durante 8 semanas. Foram feitas avaliações da pressão arterial pulmonar média, através do ecocardiograma; da qualidade de vida, através do questionário SF-36; da capacidade funcional, através do teste de caminhada de 6 minutos e da força muscular respiratória, através de transdutor de pressão. Todos os pacientes foram avaliados na fase pré e pós protocolo. Resultados: A força muscular inspiratória aumentou significativamente no grupo TMI quando comparado ao grupo controle (105,2±6,6 vs 82,9±6,1; p=0,01), e o escore de saúde mental avaliado pelo questionário SF-36 aumentou no grupo TMI (de 70,4±21,6 para 80±14,4; p=0,05). Entretanto a capacidade funcional não apresentou alteração após o protocolo de TMI de 8 semanas. Conclusão: O TMI é capaz de aumentar a força muscular inspiratória e melhorar a qualidade de vida, em relação a saúde mental, de pacientes com HP. / Introduction: Besides showing pulmonary hypertension (PH), decreased functional capacity, quality of life and survival, patients also present respiratory muscle weakness, which may contribute to increased fatigue and dyspnea symptoms. Objectives: Evaluate the effects of inspiratory muscle training (IMT) on functional capacity, quality of life, respiratory muscle strength, pulmonary artery pressure, pulmonary function and level of physical activity. Methods: Twelve chronic PH patients randomized to a control group (n = 7) and an IMT group (n = 5) were studied. The IMT program was performed for 8 weeks. The following measures were obtained before and after the program: respiratory muscle function; function capacity (6-min walk test); pulmonary artery pressure; quality of life (SF-36); and level de physical activity (IPAQ). Results: Maximal inspiratory pressure (PI,max) was higher in the IMT group than in the control group (105.2±6.6 vs 82.9±6.1; p=0.01), and the mental health score by SF-36 increased in de IMT group (from 70.4±21.6 to 80±14.4; p=0.05). However, the six-min walk test did not change after the IMT program. Conclusions: This study indicates that IMT results in improvement in inspiratory muscle strength and in the quality of life regarding PH.

Objetivos: Avaliar a percepção da dispneia em pacientes com fibrose cística (FC) comparando com indivíduos normais, durante teste com cargas resistivas inspiratórias e durante teste de caminhada de seis minutos (TC6M). Secundariamente, avaliar a correlação entre os escores de dispneia induzida pelas cargas resistivas e os escores de dispneia provocada pelo TC6M. Métodos: estudo transversal em pacientes com FC (≥15 anos) e indivíduos normais. Os voluntários foram submetidos a teste com cargas resistivas inspiratórias, medida das pressões respiratórias máximas, espirometria, avaliação nutricional e TC6M. Resultados: Foram incluídos no estudo 31 pacientes com FC pareados com 31 indivíduos normais. À medida que a magnitude das cargas resistivas inspiratórias aumentou, os escores de dispneia aumentaram (p<0,001), porém não houve diferença entre grupos quanto ao escore de dispneia (p=0,654) e não houve efeito de interação (p=0,654). SpO2 foi menor em pacientes com FC (p<0,001) e aumentou à medida que a magnitude das cargas aumentou (p<0,001), sem ocorrer efeito de interação (p=,364). Vinte e seis (84%) indivíduos normais completaram o teste com cargas resistivas, comparado com apenas 12 (39%) dos pacientes com FC (p<0,001). Os escores de dispneia foram maiores ao final do TC6M do que no repouso (p<0,001), mas não houve diferença entre os grupos (p=0,080) e não houve efeito de interação (p=0,091). SpO2 foi menor nos pacientes com FC (p<0,001) e diminuiu do repouso ao final do TC6M nos pacientes com FC (p<0,001) com efeito de interação (p=0,004). Os escores de dispneia ao final do TC6M correlacionaram-se significativamente com os escores de dispneia induzidos pelo teste com cargas resistivas. Conclusão: a percepção da dispneia em pacientes com FC induzidos por teste com cargas resistivas inspiratórias e pelo TC6M não diferiu dos indivíduos normais. Contudo, os pacientes com FC descontinuaram o teste com cargas resistivas inspiratórias mais frequentemente. Além disso, houve correlação significativa entre o escore de percepção da dispneia induzida pelas cargas resistivas inspiratórias e pelo TC6M. / Objectives: To evaluate dyspnea perception in cystic fibrosis (CF) patients compared with normal subjects, during inspiratory resistive loading and the six-minute walk test (6MWT). Secondarily, to assess the correlation between dyspnea scores induced by resistive loads and those induced by the 6MWT. Methods: cross-sectional study in patients with CF (≥15 years old) and normal subjects. Volunteers underwent inspiratory resistive loading, measurement of maximal respiratory pressures, spirometry, nutritional evaluation, and the 6MWT. Results: Thirty-one CF patients and 31 paired normal subjects were included in the study. As the magnitude of the inspiratory loads increased, dyspnea scores increased (p<.001), but there was no difference between groups in dyspnea score (p=.654) and no group interaction effect (p=.654). SpO2 was lower in CF patients (p<.001) and increased as the magnitude of the loads increased (p<.001), with no interaction effect (p=.364). Twenty-six (84%) normal subjects completed the whole test, compared to only 12 (39%) CF patients (p<.001). Dyspnea scores were higher post-6MWT than at rest (p<.001), but did not differ between groups (p=.080) with no interaction effect (p=.091). SpO2 was lower in CF patients (p<.001) and decreased from resting to post-6MWT in CF patients (p<.001) with an interaction effect (p=.004). Post-6MWT dyspnea scores were significantly correlated with dyspnea scores induced by resistive loads. Conclusion: dyspnea perception in CF patients induced by inspiratory resistive loading and by 6MWT did not differ from normal subjects. However, CF patients discontinued inspiratory resistive loading more frequently. In addition, there were significant correlations between dyspnea perception score induced by inspiratory resistance loading and by the 6MWT.

Made available in DSpace on 2015-07-22T20:50:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-31 / As alterações fisiológicas presentes no processo de envelhecimento podem acarretar declínios fisiológicos marcantes na função pulmonar e metabólica, podendo afetar na qualidade de vida do idoso. O envelhecimento está associado à resistência a insulina, caracterizada pela diminuição da resposta insulínica aos estímulos, cujos efeitos progressivos podem levar a intolerância à glicose e diabetes tipo 2. Sendo assim, o objetivo proposto neste estudo foi investigar a influência do treinamento muscular inspiratório através do Threshold® sobre a resistência à insulina em pessoas idosas. O estudo envolveu a participação de 14 pacientes idosos voluntários, com idade variando de 61 a 82 anos, sedentários, com IMC entre 18,75 a 36,7, resistentes à insulina, de ambos os sexos, sem patologias pulmonares e cardiovasculares prévias do ambulatório do Hospital Geral de Taipas. Os pacientes selecionados foram submetidos à avaliação laboratorial, a avaliação física e avaliação cardiorrespiratória. Sendo posteriormente divididos em dois grupos: Grupo controle e Grupo experimental. O programa teve duração de 12 semanas e ambos os grupos realizaram o treinamento 07 vezes por semana, sendo 06 vezes domiciliar e 01 vez no ambulatório com duração de 30 minutos diários. Após o término de 12 semanas, todos os pacientes foram reavaliados, onde a comparação dos grupos após o período de estudo mostrou que o grupo que sofreu intervenção obteve melhora da força e desempenho muscular respiratório e diminuição dos valores metabólicos, sendo considerado estatisticamente significativo a diminuição dos valores de glicemia, insulina e do HOMA IR, dado este importante devido a correlação entre envelhecimento e resistência à insulina. Os dados sugerem que o treinamento muscular inspiratório melhora a sensibilidade à insulina em pacientes portadores de resistência à insulina. / The physiological degenerations in the aging process can cause physiological decline in the pulmonary and metabolic function, being able to affect in the elder quality of life. The aging is association with insulin resistance, characterized for the reduction of the insulin reply to the stimulations, whose gradual effect can take the glucose intolerance and diabetes type 2. Therefore, the objective in this study was to investigate the influence of the inspiratory muscular training through the Threshold® on the insulin resistance in aged people. The study involved the participation of 14 elder voluntaries, with age between 61 and 82 years old, sedentaries, with BMI between 18,75 - 36,7 and insulin resistants with lipids alterations, of both genders, without previous pulmonary and cardiovascular disease at the clinic of the Taipas Hospital. The selected patients have been submitted to the Laboratorial Test, the physical Test and Cardiopulmonary Test. After the test, the patients were divided in two groups: Control group and Experimental Group. The program had duration of 12 weeks and both the groups did the inspiratory muscle training 07 times per week, being 06 times domiciliary and 01 time in the clinic with duration of 30 minutes daily. All tests were repeated after 12 weeks of inspiratory muscle training, where the comparison between the groups after the period of study showed that the group that suffered intervention got an improvement of the respiratory muscular performance and force, reduction of metabolic values. It being considered statistical significant the reduction of the values in glicemic, insulin and HOMA IR, this is important because the correlation between aging and insulin resistance. The data suggest that the inspiratory muscle training improves the insulin sensibility in insulin resistance patients. / TEDE / BV UNIFESP: Teses e dissertações

Introdução: A aplicação da pressão positiva expiratória (EPAP) em pacientes com DPOC durante o exercício pode reduzir a hiperinflação dinâmica (HD) e consequentemente a dispneia, enquanto, por outro lado, pode aumentar o trabalho resistivo da respiração. O objetivo do presente estudo foi avaliar os efeitos de duas intensidades de EPAP sobre a capacidade inspiratória, dispneia e tolerância ao exercício em pacientes com DPOC moderada a muito grave. Métodos: Estudo transversal, experimental, de 4 visitas. Na visita 1, os participantes realizaram um teste de exercício cardiopulmonar incremental limitados por sintomas (TECP). Nas visitas 2-4, com pelo menos 48 horas de intervalo, em ordem aleatória, eles realizaram TECP com carga constante (TECPct; 75% da carga de pico) sem EPAP, EPAP com 5cmH2O (EPAP5), ou EPAP com 10cmH2O (EPAP10). Resultados: O estudo incluiu 15 participantes não hipoxêmicos com DPOC moderada a muito grave (média de VEF1= 35,3 ± 10,9% do previsto). As intensidades sucessivas de EPAP durante o TECPct tenderam a causar uma redução progressiva da tolerância ao exercício (p=0,11). Destaca-se que 10 dos 15 pacientes apresentaram menor duração de exercício quando o EPAP10 foi comparado ao teste sem EPAP (-151 ± 105s, p <0,01 ou -41 ± 26%). Além disso, observou-se com EPAP (p <0,05) uma redução significativa da ventilação minuto, as custas de uma restrição na expansão do volume corrente. Por fim, a sensação de dispneia e medidas seriadas da capacidade inspiratória durante o exercício não foram diferentes entre as três intervenções. Conclusão: Níveis progressivos de EPAP durante o exercício tendem a causar uma redução progressiva na tolerância ao exercício em pacientes com DPOC sem melhora na dispneia e HD. / Introduction: The application of expiratory positive aiway pressure (EPAP) in COPD patients during exercise may reduce dynamic hyperinflation (DH), and consequently dyspnea, while, on the other hand, can increase the resistive work of breathing. Therefore, the objective of the current study was to evaluate the effects of two intensities of EPAP on inspiratory capacity, dyspnea and exercise tolerance in patients with moderate to very-severe COPD. Methods: Cross-sectional, experimental, 4-visit study. In the Visit 1, participants performed symptom-limited cycling incremental cardiopulmonary exercise test (CPET). In Visits 2-4, at least 48hrs apart, in a randomized order, they performed constant CPET (ctCPET) without EPAP, EPAP with 5cmH2O (EPAP5), or EPAP with 10cmH2O (EPAP10). Results: The study included 15 non-hypoxemic subjects ranging from moderate-to-very-severe COPD (mean FEV1=35.3 ± 10.9% of predicted). Successive intensities of EPAP during ctCPET tended to cause a progressive reduction in exercise tolerance (p=0.11). Of note, 10 of 15 presented shorter exercise duration when EPAP10 was compared to the test without EPAP (-151±105s, p<0.01 or -41±26%). Moreover, significant constraint to minute-ventilation, at expenses of limited tidal volume expansion, was observed with EPAP (p<0.05). Finally, dyspnea sensation and IC measurements were similar during exercise among the interventions. Conclusion: Progressive levels of EPAP during exercise tented to cause a progressive reduction in exercise tolerance in COPD patients without improvement in exercise dyspnea and DH.

Made available in DSpace on 2016-12-12T17:32:55Z (GMT). No. of bitstreams: 1 Cintia Laura Pereira de Araujo.pdf: 891905 bytes, checksum: 68d6cdcc41dfe7c353a29f0ca21b680c (MD5) Previous issue date: 2013-07-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Evidence has shown that dynamic hyperinflation (DH) is an important factor leading to dyspnea and consequent limitations in functional capacity of COPD patients. It is not been completely elucidated whether the pursed-lips breathing (PLB) is able to minimize DH and its effects on exercise tolerance in these patients. The aim of this study was to evaluate the acute effect of PLB on DH and functional capacity in patients with COPD. Twenty-five patients with COPD (16 men, mean age 64±7 years, FEV1=41.7±14.7% predicted, BMI=27.6±5.13kg/m2) randomly performed two six-minute walk tests with and without PLB (6MWTPLB and 6MWTNon-PLB) and two Glittre-ADL tests with and without PLB (TGlittrePLB e TGlittreNon-PLB). At baseline and immediately after the tests, the inspiratory capacity (IC) was assessed by the slow vital capacity (SVC) maneuver. The 6MWTNon-PLB and TGlittreNon-PLB induced similar DH magnitude (0.22±0.24L and. 0.31±0.23L respectively; p>0.05). PLB did not improve DH induced by the 6MWT (0.24±0.20L PLB and 0.22±0,24L non-PLB, respectively; p>0.05). DH in the TGlittrePLB was significantly lower than TGlittreNon-PLB (0.19±0.20L and 0.31±0.23L, respectively; p=0.02). PLB did not improve exercise tolerance neither on the 6MWT (457±63m PLB and 466±71m Non-PLB, respctively; p>0.05) or on the TGlittre (4.38min PLB and 4.23min Non-PLB, respectively; p>0.05). In conclusion, PLB reduced DH only on TGlittre and did not improve functional capacity. / Evidências têm demonstrado que a hiperinsuflação dinâmica é um dos fatores que levam a dispneia e consequente limitação na capacidade funcional de indivíduos com DPOC. Não está completamente elucidado se o freno labial (FL) é capaz de minimizar a hiperinsuflação dinâmica e seus efeitos na tolerância ao exercício nesses pacientes. O objetivo desse estudo foi avaliar os efeitos agudos do freno labial na hiperinsuflação dinâmica e na tolerância ao exercício em pacientes com DPOC moderada a muito grave. Vinte e cinco pacientes com DPOC (16 homens, 64±7 anos, VEF1=41,7±14,7% do previsto, IMC=27,6±5,13kg/m2) realizaram em dois dias, de forma aleatória dois testes de caminhada de seis minutos com e sem freno labial (TC6MFL e TC6MSem-FL) e dois testes de AVD-Glittre com e sem freno labial (TGlittreFL e TGlittreSem-FL). Antes e após cada teste foi avaliada a capacidade inspiratória (CI), por meio de espirometria simples com manobra de capacidade vital lenta (CVL) para avaliar a hiperinsuflação dinâmica (HD). O TC6MSem- FL e TGlittreSem-FL induziram similar magnitude de HD (0.22±0.24L vs. 0.31±0.23L; p>0.05). HD induzida pelo TGlittreFL foi significativamente menor que a induzida pelo TGlittreSem-FL (0.19±0.20L vs. 0.31±0.23L; p=0.02). FL não melhorou a HD induzida pelo TC6M (0.24±0.20L FL vs. 0.22±0,24L Sem-FL; p>0.05). FL não melhorou o desempenho no TC6M (457±63m FL vs. 466±71m Sem-FL; p>0.05); nem no TGlittre (4.38min FL vs. 4.23min Sem-FL; p>0.05). Conclui-se que o FL reduziu apenas a HD induzida pelo TGlittre e não melhorou o desempenho nos testes.

Introdução: A aplicação da pressão positiva expiratória (EPAP) em pacientes com DPOC durante o exercício pode reduzir a hiperinflação dinâmica (HD) e consequentemente a dispneia, enquanto, por outro lado, pode aumentar o trabalho resistivo da respiração. O objetivo do presente estudo foi avaliar os efeitos de duas intensidades de EPAP sobre a capacidade inspiratória, dispneia e tolerância ao exercício em pacientes com DPOC moderada a muito grave. Métodos: Estudo transversal, experimental, de 4 visitas. Na visita 1, os participantes realizaram um teste de exercício cardiopulmonar incremental limitados por sintomas (TECP). Nas visitas 2-4, com pelo menos 48 horas de intervalo, em ordem aleatória, eles realizaram TECP com carga constante (TECPct; 75% da carga de pico) sem EPAP, EPAP com 5cmH2O (EPAP5), ou EPAP com 10cmH2O (EPAP10). Resultados: O estudo incluiu 15 participantes não hipoxêmicos com DPOC moderada a muito grave (média de VEF1= 35,3 ± 10,9% do previsto). As intensidades sucessivas de EPAP durante o TECPct tenderam a causar uma redução progressiva da tolerância ao exercício (p=0,11). Destaca-se que 10 dos 15 pacientes apresentaram menor duração de exercício quando o EPAP10 foi comparado ao teste sem EPAP (-151 ± 105s, p <0,01 ou -41 ± 26%). Além disso, observou-se com EPAP (p <0,05) uma redução significativa da ventilação minuto, as custas de uma restrição na expansão do volume corrente. Por fim, a sensação de dispneia e medidas seriadas da capacidade inspiratória durante o exercício não foram diferentes entre as três intervenções. Conclusão: Níveis progressivos de EPAP durante o exercício tendem a causar uma redução progressiva na tolerância ao exercício em pacientes com DPOC sem melhora na dispneia e HD. / Introduction: The application of expiratory positive aiway pressure (EPAP) in COPD patients during exercise may reduce dynamic hyperinflation (DH), and consequently dyspnea, while, on the other hand, can increase the resistive work of breathing. Therefore, the objective of the current study was to evaluate the effects of two intensities of EPAP on inspiratory capacity, dyspnea and exercise tolerance in patients with moderate to very-severe COPD. Methods: Cross-sectional, experimental, 4-visit study. In the Visit 1, participants performed symptom-limited cycling incremental cardiopulmonary exercise test (CPET). In Visits 2-4, at least 48hrs apart, in a randomized order, they performed constant CPET (ctCPET) without EPAP, EPAP with 5cmH2O (EPAP5), or EPAP with 10cmH2O (EPAP10). Results: The study included 15 non-hypoxemic subjects ranging from moderate-to-very-severe COPD (mean FEV1=35.3 ± 10.9% of predicted). Successive intensities of EPAP during ctCPET tended to cause a progressive reduction in exercise tolerance (p=0.11). Of note, 10 of 15 presented shorter exercise duration when EPAP10 was compared to the test without EPAP (-151±105s, p<0.01 or -41±26%). Moreover, significant constraint to minute-ventilation, at expenses of limited tidal volume expansion, was observed with EPAP (p<0.05). Finally, dyspnea sensation and IC measurements were similar during exercise among the interventions. Conclusion: Progressive levels of EPAP during exercise tented to cause a progressive reduction in exercise tolerance in COPD patients without improvement in exercise dyspnea and DH.