Effects of arm bracing posture on respiratory muscle strength and pulmonary function in patients with chronic obstructive pulmonary disease.

OBJECTIVE: To analyze the effect of arm bracing posture on respiratory muscle strength and pulmonary function in patients with Chronic Obstructive Pulmonary Disease (COPD). METHODS: 20 patients with COPD (11 male; 67 ± 8 years; BMI 24 ± 3 Kg · m⁻²) were submitted to assessments of Maximal Inspiratory and Expiratory Pressures (MIP and MEP, respectively) and spirometry with and without arm bracing in a random order. The assessment with arm bracing was done on standing position and the height of the support was adjusted at the level of the ulnar styloid process with elbow flexion and trunk anterior inclination of 30 degrees promoting weight discharge in the upper limbs. Assessment without arm bracing was also performed on standing position, however with the arms relaxed alongside the body. The time interval between assessments was one week. RESULTS: MIP, MEP and maximal voluntary ventilation (MVV) were higher with arm bracing than without arm bracing (MIP 64 ± 22 cmH2O versus 54 ± 24 cmH2O, p = 0,00001; MEP 104 ± 37 cmH2O versus 92 ± 37 cmH2O, p = 0,00001 and MVV 42 ± 20 L/min versus 38 ± 20 L/min, p = 0,003). Other variables did not show statistical significant difference. CONCLUSION: The arm bracing posture resulted in higher capacity to generate force and endurance of the respiratory muscles in patients with COPD.

Adaptação do threshold IMT para teste de resistencia dos musculos inspiratorios / Adaptation of ThresholdIMT for endurance test on inspiratory muscles

Para avalaicao da resistencia muscular inspirtoria atraves de dispositivos do tipo threshold loading estudos anteriores empregaram equipamentos artesanais e indisponiveis comercialmente. Objetivos: verificar a aplicabilidade e reprodutibilidade de um teste de resistencia muscular inspiratoria utilizando a adaptacao de um antigo modelo do THRESHOLD IMT (nao disponivel comercialmente) com ampla gama de pressoes, avalaindo sua resistencia intrinseca ao fluxo inspiratorio, sua caracteristica limiar pressorica e sua relativa independencia do fluxo aereo na geracao de pressao durante os testes. Metodos: um antigo modelo do THRESHOLD IMT foi aberto, retirado sua mola interna e adaptado seu embolo. Apos montagem vertical, um sistema de peso externo foi instalado como gerador de carga. Valvulas foram instaladas para evitar re-inalacao de gas carbonico. Essa adaptacao foi testada aplicando-se diversas razoes de fluxosem a presenca do embolo e de carga para avaliacao da resistencia intrinseca e aplicando-se diversas razoes de fluxo quando instaladas cargas de 10 ate 130 cmH2O para avaliar a real pressao de abertura da valvula e o comportamento pressorico em altas razoes de fluxo. Resultados: a resistencia media foi de 4,8+-0,7 cmH2O/L.s-1, mas teve seu valor aumentado proporcionalmente ao fluxo. A pressao real de abertura foi inferior ao valor esperado (p=0,002), condicao encontrada em outros estudos. O comportamento pressorico apos a abertura da valvula foi similar em todas as cargas: um aumento medio de 3,8+-2,0 cmH2O para cada 1,0 L/S de fluxo gerado. Conclusao: a adaptacao proposta do THRESHOLD IMT produziu um dispositivo barato e confiavel para emprego em testes de resistencia muscular inspiratoria

Effects of gender and aerobic fitness on cardiac autonomic responses to head-up tilt in healthy adolescents.

Cardiovascular autonomic responses to orthostatic challenges are affected by gender and cardiorespiratory fitness in adults. However, little is know about the effects of these factors in healthy adolescents. We studied 41 adolescents (20 boys and 21 girls) aged 12-17 years, divided into aerobic fitness tertiles based on the results of a maximal treadmill exercise test. Cardiac autonomic modulation was assessed by heart rate variability (HRV) analysis of 5-minute RR interval recordings before and after 70 degrees head-up tilt maneuver. HRV was analyzed by time (TD) and frequency domain (FD) methods. TD was analyzed by standard deviation of the RR intervals and the root mean square of successive differences of RR intervals. The power spectral components were studied at low (LF) and high (HF) frequencies and as the LF/HF ratio. We did not find any differences in TD and FD measures before and after tilt in either gender or fitness groups, except for a higher heart rate response for boys. These results suggests that cardiac autonomic responses to head-up tilt in healthy adolescents are not affected by gender or aerobic fitness.

Effects of isolated cycle ergometer training on patients with moderate-to-severe chronic obstructive pulmonary disease.

BACKGROUND: Pulmonary rehabilitation (PR) programs are beneficial to patients with chronic obstructive pulmonary disease (COPD), and lower-extremity training is considered a fundamental component of PR. Nevertheless, the isolated effects of each PR component are not well established. OBJECTIVE: We aimed to evaluate the effects of a cycle ergometry exercise protocol as the only intervention in a group of COPD patients, and to compare these results with a control group. METHODS: 25 moderate-to-severe COPD patients were evaluated regarding pulmonary function, respiratory muscle strength, exercise capacity, quality of life and body composition. Patients were allocated to one of two groups: (a) the trained group (TG; n = 13; 6 men) was submitted to a protocol of 24 exercise sessions on a cycle ergometer, with training intensity initially set at a heart rate (HR) close to 80% of maximal HR achieved in a maximal test, and load increase based on dyspnea scores, and (b) the control group (CG; n = 12; 6 men) with no intervention during the protocol period. RESULTS: TG showed within-group significant improvements in endurance cycling time, 6-min walking distance test, maximal inspiratory pressure and in the domain 'dyspnea' related to quality of life. Despite the within-group changes, no between-group significant differences were observed. CONCLUSION: In COPD patients, the results of isolated low-to-moderate intensity cycle ergometer training are not comparable to effects of multimodality and high-intensity training programs.

Influencia da saturacao de O2 na velocidade do teste de distancia percorrida em 6 minutos, em pacientes com DPOC grave / Influence of O2 saturation on the Speed of the Six-minute walking distance test in severe COPD patients

Pacientes com doenca pulmonar obstrutiva cronica (DPOC) frequentemente apresentam capacidade de exercicio reduzida, entretanto, a influencia da saturacao de O2 ao repouso (SpO2r) e/ou da dessaturacao de O2 ao exercicio(DES) na capacidade de exercicio de pacientes com DPOC grave nao esta totalmente esclarecida. O objetivo deste estudo foi analisar a distancia percorrida em seis minutos (DP6) por pacientes com DPOC grave, classificados de acordo com a SpO2r e a DES. Metodos: Foram estudados 20 pacientes (12 homens e 8 mulheres) com DPOC grave ]VEF 30,95]+-6,90(por cento) que apresentaram dessaturacao >- 4(por cento) durante teste DP6. Os pacientes faram divididos em dois grupos, de acordo com a SpO2r: baixa saturacao ao repouso (BSR) ]SpO2<-92 (por cento) (n=11) e baixa saturacao ao exercico (BSE) ]SpO2>92 (por cento) (n=9). Para analise estatistica utilizou-se teste t de Student e o teste de Chi-quadrado. Resultados: DP6 foi 339,09+-111,35m (grupo BSR) e 456,78+-48,54m (grupo BSE), p=0,004. A frequencia de interrupcao do teste da DP6 foi maior no grupo BSR(p=0,01). Houve correlacao significativa entre a SpO2 durante o teste e a velocidade de caminhada a cada minuto no grupo BSR(r=0,86, p=0,03), enquanto no grupo BSE nao houve correlacao significativa (r=0,59, p=0,22). Conclusao: O grupo BSR apresentou menor capacidade de exercicio funcional que o grupo BSE. Alem disso, nos pacientes do grupo BSR ha relacao entre SpO2 e a velocidade de caminhada no teste da DP6

Relacao entre capacidade de ventilatoria e exercicio em pacientes com doenca pulmonar obstrutiva cronica moderada grave / Ventilatory capacity and exercise in patients suffering from moderate-severe chronic obstructive pulmonary disease

Este estudo tem por objetivo verificar a influencia da capacidade ventilatoria na capacidade de exercicio do paciente com doenca pulmonar obstrutiva cronica (DPOC). Participaram do estudo 38 pacientes com DPOC moderada-grave (VEF <60 por cento do previsto e VEF/CVF< 90 por cento do previsto), sendo 19 homens e 19 mulheres, com idade media de 65,00+-9,94 anos, peso 59,78+-15,74 kg, altura 157, 76 +-8,65 com VEF 36,94 +-11,74 do previsto (media+-dpm). Os pacientes foram submetidos a espirometria, prova de pressoes respiratorias maximas e teste da distancia percorrida em seis minutos (DP6min). Foi realizada a prova de ventilacao voluntaria maxima (VVM) e calculados os valores da reserva ventilatoria (RV) e o indice de reserva ventilatoria (IRV) baseados na VVM e no volume minuto (VM). A forca muscular respiratoria foi medida pela pressao inspiratoria maxima (PImax) e pressao expiratoria maxima(PEmax). A capacidade de exercicio foi avaliada pela DP6min. Para analise estatistica utilizou-se a correlacao simples de Pearson (p<0,05). Os pacientes apresentaram DP6min media de 410, 29+-129, 57m, RV 23,64+-11,45 litros, IRV 66,89+-13,84 POR CENTO, VVM 34,01+-12,49 por cento do previsto, PImax -55,26+-22,02 cmH2O e PEmax 100,74+-31,78cmH2O. A RV (r=0,76), a IRV (r=0,71), a VVM (r=0,68) e a PImax (r=0,43) apresentaram correlacao significativa com a DP6min. Portanto, a VVM, a RV, o IRV e a PImax influenciam a capacidade de exercicio submaximo de pacientes com DPOC moderada-grave