The relationship between constant work rate exercises and dynamic hyperinflation in patients with stable COPD / 实用医学杂志

Objective To study the relationship between the constant work rate exercises and dynamic hyperinflation in patients with stable COPD. Methods Routine lung ventilation function and 80%Wmax constant power bicycle ergometer exercises were tested in 30 stable COPD patients. We analyzed the correlation coefficient of Time of tolerant exercise , degree of dyspnea , VO2 max%, VO2 @kgmax% and IC%. Results All COPD patients existed varying degrees of exercise capacity accompaning with dynamic hyperinflation in the bicycle ergometer exercises. By Spearman correlation analysis , the VO2 @kg% of constant power exercises in patients with COPD is correlated with the DH% (r = -0.480, P = 0.007) and ICq% (r = 0.667, P = 0.01). Conclusion Dynamic hyperinflation is probably the prominent factors for the capability of constant work rate exercises in patients with stable COPD. Inhibition of dynamic hyperinflation may help improve exercise capability in patients with constant power exercise.

Efeitos da ventilação não-invasiva sobre a hiperinsuflação dinâmica de pacientes com DPOC durante atividade da vida diária com os membros superiores / Effects of noninvasive ventilation on dynamic hiperinflation of patients with COPD during activities of daily living with upper limbs

CONTEXTUALIZAÇÃO: Pacientes com doença pulmonar obstrutiva crônica (DPOC) queixam-se de dispneia nas atividades de vida diária (AVD) com os membros superiores (MMSS). A hiperinsuflação dinâmica (HD) é um dos mecanismos ventilatórios que contribuem para a dispneia. Para minimizar a HD, propõe-se a utilização de sistemas de ventilação não-invasiva (VNI). OBJETIVOS: Verificar se existe HD e dispneia durante a realização de uma AVD com os MMSS com e sem o uso da VNI. MÉTODOS: Participaram 32 pacientes com DPOC de moderada a muito grave, com idades entre 54 a 87 anos (69,4±7,4). Os pacientes elevaram potes com pesos de 0,5 a 5 kg durante 5 minutos, iniciando a elevação a partir da cintura pélvica em direção a uma prateleira localizada acima da cabeça, com e sem o uso da VNI (BiPAP®; IPAP 10 cmH2O; EPAP 4 cmH2O). Foram avaliadas a capacidade inspiratória (CI) e a dispneia (Escala de Borg). A CI foi mensurada antes e após a simulação da AVD. Na análise dos dados foram utilizados o teste t de Student para amostras dependentes e o teste de Wilcoxon. RESULTADOS: Houve redução significativa da CI após a AVD com e sem VNI (p=0,01). A dispneia aumentou após a AVD com e sem a VNI, mas entre ambos os protocolos não houve diferença. CONCLUSÕES: A simulação da AVD com os MMSS resultou em aumento da HD e dispneia. A VNI ofertada com pressões preestabelecidas não foi suficiente para evitar a HD e a dispneia.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) complain of dyspnea on activities of daily living (ADLs) with the upper limbs. Dynamic hyperinflation (DH) is one of the ventilatory mechanisms that may contribute towards dyspnea. To minimize the DH it is indicated the use of noninvasive ventilation (NIV). OBJECTIVES: To verify whether there is DH and dyspnea during the performance of ADL with the upper limbs with and without the use of NIV. METHODS: 32 patients with moderate-to-severe COPD, aged 54 to 87 years (mean 69.4, SD 7.4) were evaluated. The subjects lift up containers weighing between 0.5 and 5.0 kg over a five-minute period, starting from the waist level and putting them onto a shelf located above head height, with and without the use of NIV (BiPAP®; IPAP 10cmH2O; EPAP 4 cmH2O). The inspiratory capacity (IC) and dyspnea (Borg scale) were evaluated on all the patients. The IC was measured before and after simulation of the ADL. In order to analyze the data, Student's t test for dependent samples and the Wilcoxon test were used. RESULTS: There were statistically significant reductions in IC after the ADL with and without NIV (p=0.01). The dyspnea increased after the ADL with and without the NIV, however between both interventional procedures protocols no between-group difference was observed. CONCLUSIONS: The simulation of an ADL with the upper limbs resulted in an increase in DH and dyspnea. The NIV supplied with pre-established pressure was not enough to prevent the DH and dyspnea.

Ventilación mecánica en paciente con enfermedad pulmonar obstructiva crónica / Mechanical ventilation in patient with chronic obstructive pulmonary disease

La enfermedad pulmonar obstructiva crónica (EPOC) es un problema sanitario y económico mundial. En los pacientes que presentan exacerbación aguda y son hospitalizados, alrededor del 8 por ciento requieren soporte ventilatorio. La ventilación no invasiva es el tratamiento de primera línea en la falla respiratoria, no obstante, la ventilación mecánica invasiva también es requerida. Un buen entendimiento de la fisiopatología de la vía aérea y de la mecánica respiratoria es necesario para un mejor manejo de las exacerbaciones y la falla respiratoria. La hiperinsuflación dinámica a nivel pulmonar derivado de una limitación de los flujos espiratorios es un hecho cardinal. Por ello, es necesario una óptima programación del ventilador mecánico que privilegie el vaciamiento espiratorio de los pulmones, mejorar el intercambio gaseoso y minimizar el trabajo respiratorio del paciente. Esta revisión discute las alteraciones fisiopatológicas y mecánicas respiratorias en el paciente con EPOC exacerbado y las técnicas ventilatorias para optimizar el manejo de la falla respiratoria hipercápnica.

Chronic obstructive pulmonary disease (COPD) is a major global healthcare problem. The patients that present acute exacerbation and are hospitalized, about 8 percent needs support ventilator. The noninvasive ventilation is the treatment of the first line in the respiratory failure, nevertheless, the mechanical invasive ventilation also is needed. A good understanding of the airway pathophysiology and lung mechanics in COPD is necessary for a better manage of the acute exacerbations and respiratory failure. The dynamic hyperinflation derived from an expiratory airflow limitation is a cardinal fact. For management, is necessary an appropriate programming of the mechanical ventilator that favors the reducing the amount of air trapping of the lungs, to improve the gas exchange and to minimize the respiratory work of the patient. This review discusses the alterations pathophysiology and lung mechanics in the patient with acute exacerbation of COPD and ventilatory strategies.

Análise da hiperinsuflação pulmonar dinâmica (HD) após atividade de vida diária em pacientes com doença pulmonar obstrutiva crônica / Analysis of dynamic pulmonary hyperinflation (DH) following activities of daily living in patients with chronic obstructive pulmonary disease

INTRODUÇÃO: A hiperinsuflação dinâmica (HD) é um dos mecanismos ventilatórios que podem contribuir para a limitação das atividades de vida diária (AVD) em pacientes com Doença Pulmonar Obstrutiva Crônica (DPOC). Os objetivos deste trabalho foram avaliar a presença da HD, pela capacidade inspiratória (CI), e sua razão CI/CPT (capacidade pulmonar total), e a sensação de dispnéia após uma AVD realizada com os membros superiores (MMSS). MÉTODOS: Participaram 32 pacientes com DPOC de moderada a muito grave, com idades entre 54 a 87 anos (69,4 ± 7,4). Os pacientes selecionados foram submetidos a testes de função pulmonar, espirometria e pletismografia de corpo inteiro. Para as manobras espirométricas e dos volumes pulmonares, foi utilizado um sistema convencional (Vmáx22 Autobox). A CI foi determinada usando um sistema de medidas ventilatórias (Vmáx229d). Foi solicitado elevar potes com pesos de 0,5 a 5,0kg no tempo total de 5 minutos, pegando os potes em cima de uma superfície situada no nível da cintura pélvica e posicionando-os em uma prateleira localizada acima do nível da cabeça. Em todos os pacientes, foram avaliados a CI e a escala de Borg para dispnéia. Para a análise dos dados, foram utilizados o teste t de Student para amostras pareadas, a correlação de Pearson, e o teste de Wilcoxon (p< 0,05). RESULTADOS: Houve diminuição da CI e da CI/CPT (p= 0,0001) após AVD. A dispnéia aumentou após o exercício (p< 0,05). CONCLUSÃO: A AVD com os MMSS resultou em HD evidenciada pela diminuição da CI e da razão CI/CPT e, também, em aumento da dispnéia.

INTRODUCTION: Dynamic hyperinflation (DH) is one of the ventilatory mechanisms that may contribute towards limiting the activities of daily living (ADLs) in patients with chronic obstructive pulmonary disease (COPD). The objectives of this study were to evaluate the presence of DH, by means of inspiratory capacity (IC), IC / total lung capacity (TLC) ratio and by the sensation of dyspnea, following an ADL performed using the upper limbs. METHOD: The participants were 32 individuals aged 54 to 87 years (69.4 ± 7.4) who presented moderate-to-severe COPD. The patients selected underwent pulmonary function tests, spirometry and whole-body plethysmography. For the spirometric and pulmonary volume maneuvers, a conventional system was used (Vmax22 Autobox). The IC was determined using a Vmax229d ventilatory measurement system. The patients were asked to lift up pots weighing between 0.5 and 5.0 kg over a five-minute period, picking up the pots from a surface at waist level and putting them onto a shelf above head height. All the patients were evaluated regarding IC and using the Borg scale for dyspnea. The data were analyzed using Student's t test for paired samples, Pearson's correlation and the Wilcoxon test (p< 0.05). Results: There were reductions in IC and IC/TLC (p= 0.0001) following the ADL. The dyspnea increased after the exercise (p< 0.05). CONCLUSION: The ADL using the upper limbs caused DH, as shown by the reductions in IC and IC/TLC and also by the increase in dyspnea.

Mechanical Ventilation in Patients with Chronic Obstructive Pulmonary Disease / 대한구급학회지

Patients with severe chronic obstructive pulmonary disease (COPD) may require mechanical ventilation following cardiac or general surgery, in connection with thoracic surgery such as lobectomy, wedge resection, lung reduction or bullectomy, during an episode of acute respiratory failure (ARF) secondary to a disease other than COPD such as sepsis, drug overdose, or trauma or for acute-on-chronic respiratory failure (the COPD exacerbation) where acute illness, usually presumed to be infectious in nature, destabilizes the characteristically compensated state. Ventilatory intervention is often life-saving when patients with asthma or COPD experience acute respiratory compromise. Although both noninvasive and invasive ventilation methods may be viable initial choice, which is better depends upon the severity of illness, the rapidity of response, coexisting disease, and capacity of the medical environment. In addition, noninvasive ventilation often relieves dyspnea and hypoxemia in patients with stable severe COPD. This review will only briefly cover noninvasive ventilation and focus primarily on the management of the intubated, mechanically ventilated patient with COPD, with particular emphasis on factors unique to this patient population such as the propensity for dynamic hyperinflation and auto-PEEP, barotrauma, difficult weaning and the prognosis following mechanical ventilation.