Acute effects of photobiomodulation therapy applied to respiratory muscles of chronic obstructive pulmonary disease patients: a double-blind, randomized, placebo-controlled crossover trial.

To investigate the effects of photobiomodulation applied to respiratory muscles on lung function, thoracoabdominal mobility, respiratory muscle strength, and functional capacity in COPD patients. This is a randomized double-blind crossover clinical trial. Twelve male COPD patients participated in the study. Participants were randomly allocated to receive two photobiomodulation sessions, 1 week apart: (1) an effective photobiomodulation session applied at the main respiratory muscles by means of a cluster with 69 light-emitting diodes (LEDs), containing 35 red (630 ± 10 nm; 10 mW; 0.2 cm2) and 34 near-infrared (830 ± 20 nm; 10 mW; 0.2 cm2) LEDs and (2) a sham photobiomodulation session, following the same procedures without emitting light. The primary outcomes were pulmonary function (spirometric indexes); thoracoabdominal mobility (cirtometry); respiratory muscle strength (maximal respiratory pressures), assessed at three moments: (1) baseline, (2) 1 h after intervention, and (3) 24 h after intervention; and the functional capacity, assessed by the 6-min walk test (6MWT) at baseline and 24 h after intervention. No significant interactions were found for spirometric variables, maximal respiratory pressures, and cirtometry. However, there was a Time × Condition interaction (F = 18.63; p = 0.001; η2p = 0.62) in the walked distance on the 6MWT, with a significant increase after photobiomodulation intervention (p < 0.01) compared with the baseline. Photobiomodulation applied to respiratory muscles was effective in improving acute functional capacity in COPD patients. To the best of our knowledge, this is the first study assessing the effects of photobiomodulation applied to respiratory muscles in patients with COPD.

Study of Maximal Respiratory Pressures after Exposure to Breast Radiotherapy in Women: a Pilot Study / Estudo das Pressões Respiratórias Máximas após Exposição à Radioterapia de Mama em Mulheres: um Estudo-Piloto / Estudio de las Presiones Respiratorias Máximas después de la Exposición a Radioterapia Mamaria en Mujeres: un Estudio Piloto

Introduction: Postoperative radiotherapy is widely used to reduce risks of locoregional recurrence of breast cancer. However, the radiation of the thoracic structures involves risks, especially to the lungs. Objective: To study the Maximal Respiratory Pressures (MRP) after exposure to breast radiotherapy in women. Method: Prospective observational study conducted at the Alfredo Abrão Cancer Hospital in Campo Grande, State of Mato Grosso do Sul ­ MS. The study sample consisted of women (n = 8) exposed to breast radiotherapy after quadrantectomy surgery. Respiratory muscle strength was assessed through Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure (MEP) using a portable device called manovacuometer. The exam was performed before the 1st session of radiotherapy and after the 25th session corresponding to the last day of radiotherapy treatment. It were also evaluated the weight and height to measure the body mass index (BMI), clinical respiratory symptoms of dyspnea using the Medical Research Council Dyspnea Scale and characterization of cough with the Common Lung Toxicity Criteria according to the clinical pneumonitis classification. Results: MIP values were 95.90 ± 23.86 and 81.20 ± 23.12 (mean ± standard deviation p = 0.035) in relation to the ideal percentage, characterizing a significant decrease when comparing before and after breast radiotherapy exposure. It was observed level of significance of p<0.05, t-student and paired test were applied. Conclusion: The study of MRP before and after exposure to breast radiotherapy showed a significant decrease in MIP.

Introdução: No câncer de mama, a radioterapia pós-operatória é amplamente usada para reduzir a incidência de recorrência local da doença. Entretanto, a irradiação das estruturas torácicas implica riscos, especialmente para os pulmões. Objetivo: Estudar as pressões respiratórias máximas (PRM) após exposição à radioterapia de mama em mulheres. Método: Estudo prospectivo observacional realizado no Hospital de Câncer Alfredo Abrão em Campo Grande, Estado de Mato Grosso do Sul ­ MS. A amostra deste estudo foi composta por mulheres (n = 8) expostas à radioterapia de mama após cirurgia de quadrantectomia. Avaliou-se a força dos músculos respiratórios por meio da pressão inspiratória máxima (Pimáx) e da pressão expiratória máxima (Pemáx), utilizando-se do aparelho portátil denominado manovacuômetro. O exame foi realizado antes da primeira sessão de radioterapia e após a 25ª sessão, correspondendo ao último dia de tratamento radioterápico. Também foram avaliados o peso e a altura para medir o índice de massa corporal, os sintomas respiratórios clínicos de dispneia com o uso da Escala de Dispneia Medical Research Council e a caracterização de tosse com os Critérios Comuns de Toxicidade Pulmonar, em classificação da pneumonite clínica. Resultados: Os valores da Pimáx resultaram em 95,90 ± 23,86 e 81,20 ± 23,12 (média ± desvio padrão da média ­ p = 0,035) em relação ao percentual ideal, caracterizando diminuição significativa ao se comparar antes e após a exposição à radioterapia. Observou-se nível de significância de p<0,05, teste t-student e pareado. Conclusão: O estudo das PRM antes e após a exposição à radioterapia de mama evidenciou diminuição significativa da Pimáx.

Introducción: En el cáncer de mama, la radioterapia postoperatoria se usa ampliamente para reducir los riesgos de recurrencia locorregional de la enfermedad. Sin embargo, la radiación de las estructuras torácicas implica riesgos, especialmente para los pulmones. Objetivo: Estudiar las presiones respiratorias máximas (PRM) después de la exposición a la radioterapia de mama en mujeres. Método: Estudio observacional prospectivo realizado en el Hospital de Cáncer "Alfredo Abrão" en Campo Grande ­ MS. La muestra del estudio consistió en mujeres (n = 8) expuestas a radioterapia de mama después de una cirugía de cuadrantectomía. La fuerza muscular respiratoria se evaluó a través de la presión inspiratoria máxima (MIP) y la presión espiratoria máxima (MEP), utilizando un dispositivo portátil llamado manovacuómetro. El examen se realizó antes de la 1ª sesión de radioterapia y después de la 25ª sesión correspondiente al último día de tratamiento de radioterapia. También fueron evaluados el peso y la altura para calcular el índice de masa corporal; los síntomas clínicos de disnea respiratoria utilizando la Escala de disnea del "Medical Research Council", y la caracterización de la tos con los criterios comunes de toxicidad pulmonar según la clasificación de neumonitis clínica. Resultados: Los valores de MIP fueron de 95,90 ± 23,86 y 81,20 ± 23,12 en relación con el porcentaje ideal, caracterizando una disminución significativa (media ± desviación estándar de la media - p = 0,035) al comparar el antes y el después de la exposición a radioterapia mamaria. Se observó nivel de significancia de p <0,05, se aplicó t-student y prueba pareada. Conclusión: El estudio de PRM, antes y después de la exposición a radioterapia de mama, mostró una disminución significativa en la MIP.

Impact of thoracic radiotherapy on respiratory function and exercise capacity in patients with breast cancer / Impacto da radioterapia torácica na função respiratória e capacidade de exercício em pacientes com câncer de mama

ABSTRACT Objective: To evaluate the impact of thoracic radiotherapy on respiratory function and exercise capacity in patients with breast cancer. Methods: Breast cancer patients in whom thoracic radiotherapy was indicated after surgical treatment and chemotherapy were submitted to HRCT, respiratory evaluation, and exercise capacity evaluation before radiotherapy and at three months after treatment completion. Respiratory muscle strength testing, measurement of chest wall mobility, and complete pulmonary function testing were performed for respiratory evaluation; cardiopulmonary exercise testing was performed to evaluate exercise capacity. The total radiotherapy dose was 50.4 Gy (1.8 Gy/fraction) to the breast or chest wall, including supraclavicular lymph nodes (SCLN) or not. Dose-volume histograms were calculated for each patient with special attention to the ipsilateral lung volume receiving 25 Gy (V25), in absolute and relative values, and mean lung dose. Results: The study comprised 37 patients. After radiotherapy, significant decreases were observed in respiratory muscle strength, chest wall mobility, exercise capacity, and pulmonary function test results (p < 0.05). DLCO was unchanged. HRCT showed changes related to radiotherapy in 87% of the patients, which was more evident in the patients submitted to SCLN irradiation. V25% significantly correlated with radiation pneumonitis. Conclusions: In our sample of patients with breast cancer, thoracic radiotherapy seemed to have caused significant losses in respiratory and exercise capacity, probably due to chest wall restriction; SCLN irradiation represented an additional risk factor for the development of radiation pneumonitis.

RESUMO Objetivo: Avaliar o impacto da radioterapia torácica na função respiratória e capacidade de exercício em pacientes com câncer de mama. Métodos: Pacientes com câncer de mama com indicação de radioterapia torácica após tratamento cirúrgico e quimioterápico foram submetidas a TCAR, avaliação respiratória e avaliação da capacidade de exercício antes da radioterapia torácica e três meses após o término do tratamento. Foram realizados teste de força muscular respiratória, medição da mobilidade torácica e prova de função pulmonar completa para a avaliação respiratória; realizou-se teste de exercício cardiopulmonar para avaliar a capacidade de exercício. A dose total de radioterapia foi de 50,4 Gy (1,8 Gy/fração) na mama ou na parede torácica, incluindo ou não a fossa supraclavicular (FSC). Histogramas dose-volume foram calculados para cada paciente com especial atenção para o volume pulmonar ipsilateral que recebeu 25 Gy (V25), em números absolutos e relativos, e a dose pulmonar média. Resultados: O estudo incluiu 37 pacientes. Após a radioterapia, observou-se diminuição significativa da força muscular respiratória, mobilidade torácica, capacidade de exercício e resultados da prova de função pulmonar (p < 0,05). A DLCO permaneceu inalterada. A TCAR mostrou alterações relacionadas à radioterapia em 87% das pacientes, o que foi mais evidente nas pacientes submetidas à irradiação da FSC. O V25% correlacionou-se significativamente com a pneumonite por radiação. Conclusões: Em nossa amostra de pacientes com câncer de mama, a radioterapia torácica parece ter causado perdas significativas na capacidade respiratória e de exercício, provavelmente por causa da restrição torácica; a irradiação da FSC representou um fator de risco adicional para o desenvolvimento de pneumonite por radiação.

Impact of thoracic radiotherapy on respiratory function and exercise capacity in patients with breast cancer.

OBJECTIVE: To evaluate the impact of thoracic radiotherapy on respiratory function and exercise capacity in patients with breast cancer. METHODS: Breast cancer patients in whom thoracic radiotherapy was indicated after surgical treatment and chemotherapy were submitted to HRCT, respiratory evaluation, and exercise capacity evaluation before radiotherapy and at three months after treatment completion. Respiratory muscle strength testing, measurement of chest wall mobility, and complete pulmonary function testing were performed for respiratory evaluation; cardiopulmonary exercise testing was performed to evaluate exercise capacity. The total radiotherapy dose was 50.4 Gy (1.8 Gy/fraction) to the breast or chest wall, including supraclavicular lymph nodes (SCLN) or not. Dose-volume histograms were calculated for each patient with special attention to the ipsilateral lung volume receiving 25 Gy (V25), in absolute and relative values, and mean lung dose. RESULTS: The study comprised 37 patients. After radiotherapy, significant decreases were observed in respiratory muscle strength, chest wall mobility, exercise capacity, and pulmonary function test results (p < 0.05). DLCO was unchanged. HRCT showed changes related to radiotherapy in 87% of the patients, which was more evident in the patients submitted to SCLN irradiation. V25% significantly correlated with radiation pneumonitis. CONCLUSIONS: In our sample of patients with breast cancer, thoracic radiotherapy seemed to have caused significant losses in respiratory and exercise capacity, probably due to chest wall restriction; SCLN irradiation represented an additional risk factor for the development of radiation pneumonitis.

Microstimulators and intramuscular hook electrodes for the stimulation of respiratory muscles.

BACKGROUND/OBJECTIVES: We determined the feasibility of stimulating the major muscles of respiration with different types of electrodes. Intramuscular hook electrodes, model microstimulators (M-Micro) developed in our laboratory, and commercial radiofrequency microstimulators (RFM) (Alfred Mann Foundation, Valencia, CA), were employed in this investigation. METHODS: In 8 anesthetized dogs, M-Micro were placed bilaterally on the diaphragm and in the abdominal muscles, and hook electrodes were placed in the 3rd and 5th intercostal regions adjacent to the intercostal nerves known to support inspiration. In 3 of the 8 animals, RFMs (Alfred Mann Foundation) in addition to the M-Micros were sutured to each hemidiaphragm at the same optimal site for phrenic nerve stimulation. During a hyperventilation-induced apnea, 2-second stimulations were applied to the diaphragm and with various combinations of diaphragm plus supporting muscles, both thoracic and abdominal. RESULTS: Diaphragm stimulation alone provided tidal volumes adequate for basal alveolar ventilation. However, implantation of the RFM required greater contact with the muscle. Stimulating other respiratory muscles along with the diaphragm further increased tidal volumes. The hook electrodes, M-Micro, and RFM performed equally well. CONCLUSIONS: In the acute dog model, M-Micro and hook electrodes can provide an implant system for the maintenance of ventilation. Support of the intercostal and abdominal muscles has the potential to reduce the contraction requirements of the diaphragm with decreased likelihood of diaphragm fatigue and hypoventilation. Whether the electrodes under investigation could provide an implant system for long-term ventilation needs to be determined.