Effects of proportional assisted ventilation on exercise performance in idiopathic pulmonary fibrosis patients.

BACKGROUND: Patients with idiopathic pulmonary fibrosis (IPF) present an important ventilatory limitation reducing their exercise capacity. Non-invasive ventilatory support has been shown to improve exercise capacity in patients with obstructive diseases; however, its effect on IPF patients remains unknown. OBJECTIVE: The present study assessed the effect of ventilatory support using proportional assist ventilation (PAV) on exercise capacity in patients with IPF. METHODS: Ten patients (61.2+/-9.2 year-old) were submitted to a cardiopulmonary exercise testing, plethysmography and three submaximal exercise tests (60% of maximum load): without ventilatory support, with continuous positive airway pressure (CPAP) and PAV. Submaximal tests were performed randomly and exercise capacity, cardiovascular and ventilatory response as well as breathlessness subjective perception were evaluated. Lactate plasmatic levels were obtained before and after submaximal exercise. RESULTS: Our data show that patients presented a limited exercise capacity (9.7+/-3.8 mL O(2)/kg/min). Submaximal test was increased in patients with PAV compared with CPAP and without ventilatory support (respectively, 11.1+/-8.8 min, 5.6+/-4.7 and 4.5+/-3.8 min; p<0.05). An improved arterial oxygenation and lower subjective perception to effort was also observed in patients with IPF when exercise was performed with PAV (p<0.05). IPF patients performing submaximal exercise with PAV also presented a lower heart rate during exercise, although systolic and diastolic pressures were not different among submaximal tests. Our results suggest that PAV can increase exercise tolerance and decrease dyspnoea and cardiac effort in patients with idiopathic pulmonary fibrosis.

Influence of diaphragmatic mobility on exercise tolerance and dyspnea in patients with COPD.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) present increased airway resistance, air trapping, pulmonary hyperinflation, and diaphragm muscle alterations, all of which affect pulmonary mechanics. PURPOSE: To evaluate the influence diaphragmatic mobility has on exercise tolerance and dyspnea in patients with COPD. MATERIALS AND METHODS: Fifty-four COPD patients with lung hyperinflation were evaluated to assess pulmonary function, diaphragm mobility, exercise tolerance, and dyspnea (score). Twenty healthy (age- and body mass index-matched) subjects were evaluated as controls. RESULTS: The COPD patients presented lower diaphragmatic mobility than did the controls (36.27+/-10.96 mm vs. 46.33+/-9.46 mm). Diaphragmatic mobility presented a linear correlation with distance covered on the 6-min walk test (6MWT) (r=0.38; p=0.005) and a negative correlation with dyspnea (r=-0.36; p=0.007). Patients were then divided into two subgroups based on the degree of diaphragmatic mobility: G1 (or=34 mm). Those in G1 presented poorer 6MWT performance and greater dyspnea upon exertion than did those in G2 (distance covered on the 6MWT: 454.76+/-100.67 m vs. 521.63+/-70.82 m; dyspnea score: 5.22+/-3.06 vs. 3.48+/-2.77). The G1 patients also presented greater residual volume (in liters) and lower maximal voluntary ventilation (in % of predicted values) than did the G2 patients (266.20+/-55.30 vs. 209.74+/-48.49 and 39.00+/-14.94 vs. 58.11+/-20.96). CONCLUSION: Diaphragmatic mobility influences dyspnea and exercise tolerance in patients with COPD.

Comparison of two questionnaires which measure the health-related quality of life of idiopathic pulmonary fibrosis patients.

The objective of the present study was to determine if there is a health-related quality of life (HRQL) instrument, generic or specific, that better represents functional capacity dysfunction in idiopathic pulmonary fibrosis (IPF) patients. HRQL was evaluated in 20 IPF patients using generic and specific questionnaires (Medical Outcomes Short Form 36 (SF-36) and Saint George's Respiratory Questionnaire (SGRQ), respectively). Functional status was evaluated by pulmonary function tests, 6-min walking distance test (6MWDT) and dyspnea indexes (baseline dyspnea index) at rest and after exercise (modified Borg scale). There was a restrictive pattern with impairment of diffusion capacity (total lung capacity, TLC = 71.5 +/- 15.6%, forced vital capacity = 70.4 +/- 19.4%, and carbon monoxide diffusing capacity = 41.5 +/- 16.2% of predicted value), a reduction in exercise capacity (6MWDT = 435.6 +/- 95.5 m) and an increase of perceived dyspnea score at rest and during exercise (6 +/- 2.5 and 7.1 +/- 1.3, respectively). Both questionnaires presented correlation with some functional parameters (TLC, forced expiratory volume in 1 s and carbon monoxide diffusing capacity) and the best correlation was with TLC. Almost all of the SGRQ domains presented a strong correlation with functional status, while in SF-36 only physical function and vitality presented a good correlation with functional status. Dyspnea index at rest and 6MWDT also presented a good correlation with HRQL. Our results suggest that a specific instead of a generic questionnaire is a more appropriate instrument for HRQL evaluation in IPF patients and that TLC is the functional parameter showing best correlation with HRQL.

Comparison of two questionnaires which measure the health-related quality of life of idiopathic pulmonary fibrosis patients

The objective of the present study was to determine if there is a health-related quality of life (HRQL) instrument, generic or specific, that better represents functional capacity dysfunction in idiopathic pulmonary fibrosis (IPF) patients. HRQL was evaluated in 20 IPF patients using generic and specific questionnaires (Medical Outcomes Short Form 36 (SF-36) and Saint George's Respiratory Questionnaire (SGRQ), respectively). Functional status was evaluated by pulmonary function tests, 6-min walking distance test (6MWDT) and dyspnea indexes (baseline dyspnea index) at rest and after exercise (modified Borg scale). There was a restrictive pattern with impairment of diffusion capacity (total lung capacity, TLC = 71.5 ± 15.6 percent, forced vital capacity = 70.4 ± 19.4 percent, and carbon monoxide diffusing capacity = 41.5 ± 16.2 percent of predicted value), a reduction in exercise capacity (6MWDT = 435.6 ± 95.5 m) and an increase of perceived dyspnea score at rest and during exercise (6 ± 2.5 and 7.1 ± 1.3, respectively). Both questionnaires presented correlation with some functional parameters (TLC, forced expiratory volume in 1 s and carbon monoxide diffusing capacity) and the best correlation was with TLC. Almost all of the SGRQ domains presented a strong correlation with functional status, while in SF-36 only physical function and vitality presented a good correlation with functional status. Dyspnea index at rest and 6MWDT also presented a good correlation with HRQL. Our results suggest that a specific instead of a generic questionnaire is a more appropriate instrument for HRQL evaluation in IPF patients and that TLC is the functional parameter showing best correlation with HRQL.

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

Comparacao entre a escala de Borg modificada e a escala de Borg modificada analogo visual aplicadas em pacientes com dispneia / Comparison between Modified Borg Scale (MBS) to the Visual Analogue Borg Scale (EBMAV) applied in patients with dyspnea

Dispneia e um sintoma respiratorio que pode ser primario ou associado a varias condicoes patologicas. A utilizacao de instrumentos que possibilitem a graduacao da intensidade desta sencasao subjetiva de desconforto respiratorio deve ser incorporado na pratica clinica do fisioterapeuta. A literatura relata que varios instrumentos tem sido proposto para a avaliacao da intencidade da dispneia, incluindo metodos de entrevistas, questionarios auto-aplicativos e escalas numericas e visuais. A Escala de Borg Modificada e a mais utilizada na pratica clinica para a avaliacao do grau de desconforto respiratorio durante o exercito, porem sua aplicacao esta restrita a individuos alfabetizados. Diante disso, surgiu a necessidade de criar uma forma alternativa de avaliar a dispneia em pacientes analfabeticos ou com baixo grau de compreensao.entao, elaboramos uma escala com a mesma graduacao da Escala de Borg Modificada, porem, em vez de o paciente ler para dar a nota, ele se orientara por quadros que vao variar a intensidade da cor, conforme a sencacao de dispneia referida pelo paciente no momento. Denominamos este novo instrumento de medida baseado na Escala de Borg Modificada de Escala de Borg Modificada Analogo Visual. Oobjetivo deste estudo foi comparar a Escala de Borg Modificada(EBM)com a Escala de Borg Modificada Analogo Visual (EBMAV) desenvolvida em nosso setor. Foram selecionados, aleatoriamente, 23 pacientes que aguardavam atendimento no Hospital Regional do Norte do Parana (HURNPr)e que estivessem procurando o servico devido a dispneia. Todos os pacientes graduaram a intencidade da dispneia que apresentavam naquele exato momento por intermedio das duas escalas Escala de Borg Modificada (EBM)e Escala de Borg Modificada Analogo Visual (EBMAV). A medida das notas obtidas pela aplicacao das duas escalas foram de 4,83+ 1,67 para a Escala de Borg Modificada e de 4,91+ 2,19 para a Escala de Borg Modificada Analogo Visual. Nao houve diferenca significativa entre os valores das duas escalas(p=0,32), indicando similaridade entre as duas escalas na mensuracao da dispneia. A EBMAV e um recurso pratico que pode ser utilizado pelo fisioterapeuta na avaliacao de pacientes nao alfabetizados que relatam dispneia, visando graduar a intencidade dessa sencao subjetiva de desconforto respiratorio ao repouso e/ou durante o exercicio