RESUMO
In patients suffering from Coronavirus Disease 2019 (COVID-19), dyspnoea is less likely to occur despite hypoxemia. Even if the patient develops severe hypoxemia, it cannot be detected from subjective symptoms. In other words, it becomes more serious without the person or the surroundings noticing it. Initially less talked about, hypoxemia without dyspnoea (silent hypoxemia or happy hypoxia: hypoxemia that does not coincide with dyspnoea) is now experienced in many institutions. Dyspnoea is defined as "the unpleasant sensation that accompanies breathing." Dyspnoea occurs when afferent information is transmitted to the sensory area. Receptors involved in the development of dyspnoea include central and peripheral chemoreceptors, chest wall receptors, lung receptors, upper respiratory tract receptors and corollary discharge receptors. In the present study, we considered mechanisms mediating the silent hypoxemia through three cases experienced at our hospital as a dedicated coronavirus treatment hospital. We have treated about 600 people infected with COVID-19, of which about 10% were severe cases. In the present study, the patients' condition was retrospectively extracted and analysed. We investigated three typical cases of COVID-19 pneumonia admitted to our hospital (men and women between the ages of 58 and 86 with hypoxemia and tachypnoea). Silent hypoxemia is not entirely without dyspnoea, but hypoxemia does not cause dyspnoea commensurate with its severity. The virus may have specific effects on the respiratory control system. In our cases, respiratory rate significantly increased with hypoxemia, and hyperventilation occurred. Therefore, information about hypoxemia is transmitted from the carotid body. Since hyperventilation occurs, it is suggested that information is transmitted to effectors such as respiratory muscles. The fact that these patients did not feel the unpleasant sensation indicates that information is not accurately transmitted to the sensory area of the cerebral cortex. These cases suggest that there may be a problem somewhere in the path from the respiratory centre to the sensory area.
Assuntos
COVID-19 , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , SARS-CoV-2 , Hiperventilação/complicações , Estudos Retrospectivos , Dispneia/diagnóstico , HipóxiaRESUMO
BACKGROUND: The flow-volume (FV) curve pattern in the pulmonary function test (PFT) for obstructive lung diseases is widely recognized. However, there are few reports on FV curve pattern in idiopathic pulmonary fibrosis (IPF). In this study, we investigated the relationship between FV curve pattern and clinical or radiological features in IPF. METHODS: The FV curves on PFTs and chest high-resolution computed tomography (HRCT) images of 130 patients with IPF were retrospectively evaluated. The FV curves were divided into four groups based on the presence or absence of the convex and concave patterns: convex/concave, non-convex/concave, convex/non-concave, and non-convex/non-concave. Using a computer-aided system, CT honeycombing area (%HA) and subtracted low attenuation area (%sLAA) were quantitatively measured. To assess the distribution of CT findings, the lung area was divided into upper, lower, central, and peripheral areas. The relationships of FV curve patterns with patient characteristics, spirometry results, and quantitative CT findings were evaluated. RESULTS: The patients with convex pattern was identified in 93 (71.5%) and concave pattern in 72 (55.4%). Among the four groups, patients with the convex/non-concave pattern had significantly lower forced vital capacity (FVC) and higher %HA of the upper/peripheral lung area (p = 0.018, and p = 0.005, respectively). The convex/non-concave pattern was a significant predictor of mortality for IPF (hazard ratio, 2.19; p = 0.032). CONCLUSIONS: Patients with convex/non-concave pattern in FV curve have lower FVC and poorer prognosis with distinct distribution of fibrosis. Hence, FV curve pattern might be a useful predictor of mortality in IPF.
Assuntos
Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/fisiopatologia , Pulmão/patologia , Pulmão/fisiopatologia , Testes de Função Respiratória , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Fibrose Pulmonar Idiopática/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de SobrevidaRESUMO
Balloon pulmonary angioplasty (BPA) has emerged as a new treatment strategy for patients with chronic thromboembolic pulmonary hypertension (CTEPH). Improvements in hemodynamic parameters after BPA have been reported, but some patients continue to suffer from reduced exercise tolerance even after the normalization of hemodynamic parameters following BPA. As the amelioration of hemodynamic parameters is reportedly achieved via BPA, we hypothesized that the limiting factors for exercise tolerance in these patients are related to respiratory function. Therefore, we investigated the associations between respiratory function and exercise tolerance, and the mechanisms underlying respiratory dysfunction in patients after BPA. We analyzed 62 patients with CTEPH who underwent 1-year follow-up after BPA. Predictors for reduced exercise tolerance after BPA determined with six-minute walk test were sought from pulmonary hemodynamic and respiratory parameters using logistic regression analysis. After multivariate adjustments, high mean right atrium pressure (mRAP) and high alveolar-arterial oxygen gradient (A-aDO2) were significant predictors for reduced exercise tolerance. Next, we analyzed factors associated with high A-aDO2. Among the pathophysiological causes of high A-aDO2, including ventilation, diffusing capacity, and low ventilation-perfusion ratio, only low ventilation-perfusion ratio caused by high intrapulmonary shunt fraction was associated with high A-aDO2. Impaired oxygenation due to residual high intrapulmonary shunt fraction was associated with reduced exercise tolerance in patients with CTEPH, after receiving BPA.
Assuntos
Angioplastia com Balão , Hemodinâmica , Hipertensão Pulmonar/terapia , Oxigênio/sangue , Embolia Pulmonar/terapia , Idoso , Doença Crônica , Tolerância ao Exercício , Feminino , Humanos , Hipertensão Pulmonar/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/sangue , Estudos Retrospectivos , Teste de CaminhadaRESUMO
Chronic intermittent hypoxia (IH) induces oxidative stress and inflammation, which impair vascular endothelial function. Long-term insulin resistance also leads to endothelial dysfunction. We determined, in vivo, whether the effects of chronic IH and insulin resistance on endothelial function augment each other. Male 12-wk-old Goto-Kakizaki (GK) and Wistar control rats were subjected to normoxia or chronic IH (90-s N2, 5% O2 at nadir, 90-s air, 20 cycles/h, 8 h/day) for 4 wk. Coronary endothelial function was assessed using microangiography with synchrotron radiation. Imaging was performed at baseline, during infusion of acetylcholine (ACh, 5 µg·kg(-1)·min(-1)) and then sodium nitroprusside (SNP, 5 µg·kg(-1)·min(-1)), after blockade of both nitric oxide (NO) synthase (NOS) with N(ω)-nitro-l-arginine methyl ester (l-NAME, 50 mg/kg) and cyclooxygenase (COX, meclofenamate, 3 mg/kg), and during subsequent ACh. In GK rats, coronary vasodilatation in response to ACh and SNP was blunted compared with Wistar rats, and responses to ACh were abolished after blockade. In Wistar rats, IH blunted the ability of ACh or SNP to increase the number of visible vessels. In GK rats exposed to IH, neither ACh nor SNP were able to increase visible vessel number or caliber, and blockade resulted in marked vasoconstriction. Our findings indicate that IH augments the deleterious effects of insulin resistance on coronary endothelial function. They appear to increase the dependence of the coronary microcirculation on NO and/or vasodilator prostanoids, and greatly blunt the residual vasodilation in response to ACh after blockade of NOS/COX, presumably mediated by endothelium-derived hyperpolarizing factors.
Assuntos
Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/fisiopatologia , Hipóxia/complicações , Hipóxia/fisiopatologia , Resistência à Insulina , Microcirculação , Animais , Doença Crônica , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária , Progressão da Doença , Hipóxia/diagnóstico por imagem , Masculino , Ratos , Ratos WistarRESUMO
Several new fixed-dose combination bronchodilators have been launched in the world, and 3 different types are now available in Japan. Assessing their efficacy relative to each other has not been performed yet. In the present manuscript, characteristics of glycopyrronium/indacaterol, umeclidinium/vilanterol and tiotropium/olodaterol were reviewed. In particular, changes in trough and peak forced expiratory volume in 1 second (FEV1), St George's Respiratory Questionnaire (SGRQ) total scores, and transitional dyspnea index (TDI) focal scores were reviewed in these bronchodilators.
Assuntos
Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Benzoxazinas/administração & dosagem , Álcoois Benzílicos/administração & dosagem , Broncodilatadores/administração & dosagem , Clorobenzenos/administração & dosagem , Glicopirrolato/administração & dosagem , Indanos/administração & dosagem , Antagonistas Muscarínicos/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Quinolonas/administração & dosagem , Quinuclidinas/administração & dosagem , Brometo de Tiotrópio/administração & dosagem , Preparações de Ação Retardada , Combinação de Medicamentos , Volume Expiratório Forçado , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Testes de Função Respiratória , Resultado do TratamentoRESUMO
Pulmonary arterial hypertension (PAH) is prevalent in patients with obstructive sleep apnea syndrome (OSAS). Aging induces arginase activation and reduces nitric oxide (NO) production in the arteries. Intermittent hypoxia (IH), conferred by cycles of brief hypoxia and normoxia, contributes to OSAS pathogenesis. Here, we studied the role of arginase and aging in the pathogenesis of PAH in adult (9-mo-old) and young (2-mo-old) male Sprague-Dawley rats subjected to IH or normoxia for 4 weeks and analyzed them with a pressure-volume catheter inserted into the right ventricle (RV) and by pulsed Doppler echocardiography. Western blot analysis was conducted on arginase, NO synthase isoforms, and nitrotyrosine. IH induced PAH, as shown by increased RV systolic pressure and RV hypertrophy, in adult rats but not in young rats. IH increased expression levels of arginase I and II proteins in the adult rats. IH also increased arginase I expression in the pulmonary artery endothelium and arginase II in the pulmonary artery adventitia. Furthermore, IH reduced pulmonary levels of nitrate and nitrite but increased nitrotyrosine levels in adult rats. An arginase inhibitor (N(ω)-hydroxy-nor-1-arginine) prevented IH-induced PAH and normalized nitrite and nitrate levels in adult rats. IH induced arginase up-regulation and PAH in adult rats, but not in young rats, through reduced NO production. Our findings suggest that arginase inhibition prevents or reverses PAH.
Assuntos
Arginase/metabolismo , Hipertensão/enzimologia , Envelhecimento , Animais , Hipóxia Celular , Ativação Enzimática , Pulmão/enzimologia , Masculino , Nitratos/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Nitritos/metabolismo , Artéria Pulmonar/enzimologia , Artéria Pulmonar/fisiopatologia , Ratos Sprague-Dawley , Tirosina/análogos & derivados , Tirosina/metabolismoRESUMO
Sleep apnea syndrome (SAS) is considered to be associated with heart failure (HF). It is known that autophagy is induced in various heart diseases thereby promotes survival, but its excess may be maladaptive. Intermittent hypoxia (IH) plays pivotal role in the pathogenesis of SAS. We aimed to clarify the relationships among IH, autophagy, and HF. Rats underwent IH at a rate of 20cycles/h (nadir of 4% O2 to peak of 21% O2 with 0% CO2) or normal air breathing (control) for 8h/d for 3weeks. IH increased the cardiac LC3II/LC3I ratio. The IH induced upregulation of LC3II was attenuated by the administration of an inhibitor of autophagosome formation 3-methyladenine (3-MA), but enhanced by an inhibitor of autophagosome-lysosome fusion chloroquine (CQ), showing enhanced autophagic flux in IH hearts. Electron microscopy confirmed an increase in autophagosomes and lysosomes in IH. With 3-MA or CQ, IH induced progressive deterioration of fractional shortening (FS) on echocardiography over 3weeks, although IH, 3-MA, or CQ alone had no effects. With CQ, IH for 4weeks increased serum troponin T levels, reflecting necrosis. Western blotting analyses showed dephosphorylation of Akt and mammalian target of rapamycin (mTOR) at Akt (Ser2448, 2481) sites, suggesting the activation of autophagy via Akt inactivation. Conclusions. IH-mediated autophagy maintains contractile function, whereas when autophagy is inhibited, IH induces systolic dysfunction due to myocyte necrosis. General significance. This study highlighted the potential implications of autophagy in cardio-protection in early SAS patients without comorbidity, reproduced in normal rats by 3~4weeks of IH.
Assuntos
Autofagia/fisiologia , Cardiopatias/metabolismo , Hipóxia/fisiopatologia , Contração Muscular/fisiologia , Miocárdio/patologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Autofagia/efeitos dos fármacos , Cloroquina/farmacologia , Cardiopatias/patologia , Cardiopatias/fisiopatologia , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Hipóxia/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/fisiologia , Masculino , Contração Muscular/efeitos dos fármacos , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Necrose/sangue , Necrose/metabolismo , Necrose/fisiopatologia , Fagossomos/efeitos dos fármacos , Fagossomos/metabolismo , Fagossomos/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR/metabolismo , Troponina T/sangueRESUMO
Chronic intermittent hypoxia (IH) provokes a centrally mediated increase in sympathetic nerve activity (SNA). Although this sympathetic hyperexcitation has been linked to systemic hypertension, its effect on the pulmonary vasculature is unclear. This study aimed to assess IH-mediated sympathetic excitation in modulating pulmonary vasculature tone, particularly acute hypoxia vasoconstrictor response (HPV), and the central ß-adrenergic signaling pathway for facilitating the increase in SNA. Sprague-Dawley rats were exposed to IH (cycle of 4% O2 for 90 s/air for 90 s) for 8 h/day for 6 weeks. Subsequently, rats were anesthetized and either pulmonary SNA was recorded (electrophysiology), or the pulmonary vasculature was visualized using microangiography. Pulmonary sympathetic and vascular responses to acute hypoxia were assessed before and after central ß1-adrenergic receptor blockade (Metoprolol, 200 nmol i.c.v.). Chronic IH increased baseline SNA (110% increase), and exacerbated the sympathetic response to acute hypoxia. Moreover, the magnitude of HPV in IH rats was blunted compared to control rats (e.g., 10 and 20% vasoconstriction, respectively). In only the IH rats, ß1-receptor blockade with metoprolol attenuated the hypoxia-induced increase in pSNA and exacerbated the magnitude of acute HPV, so that both sympathetic and HPV responses were similar to that of control rats. Interestingly, the expression of ß1-receptors within the brainstem was similar between both control and IH rats. These results suggest that the centrally mediated increase in SNA following IH acts to blunt the local vasoconstrictor effect of acute hypoxia, which reflects an inherent difference between vasodilator and vasoconstrictor actions of SNA in pulmonary and systemic circulations.
Assuntos
Hipóxia/fisiopatologia , Pulmão/fisiopatologia , Fenômenos Fisiológicos Respiratórios , Sistema Nervoso Simpático/fisiopatologia , Angiografia/métodos , Animais , Western Blotting , Eletrofisiologia , Pulmão/irrigação sanguínea , Pulmão/inervação , Masculino , Ratos , Ratos Sprague-Dawley , Vasoconstrição/fisiologiaRESUMO
Recent advances in imaging analysis have enabled evaluation of ventilation and perfusion in specific regions by chest computed tomography (CT) and magnetic resonance imaging (MRI), in addition to modalities including dynamic chest radiography, scintigraphy, positron emission tomography (PET), ultrasound, and electrical impedance tomography (EIT). In this review, an overview of current functional imaging techniques is provided for each modality. Advances in chest CT have allowed for the analysis of local volume changes and small airway disease in addition to emphysema, using the Jacobian determinant and parametric response mapping with inspiratory and expiratory images. Airway analysis can reveal characteristics of airway lesions in chronic obstructive pulmonary disease (COPD) and bronchial asthma, and the contribution of dysanapsis to obstructive diseases. Chest CT is also employed to measure pulmonary blood vessels, interstitial lung abnormalities, and mediastinal and chest wall components including skeletal muscle and bone. Dynamic CT can visualize lung deformation in respective portions. Pulmonary MRI has been developed for the estimation of lung ventilation and perfusion, mainly using hyperpolarized 129Xe. Oxygen-enhanced and proton-based MRI, without a polarizer, has potential clinical applications. Dynamic chest radiography is gaining traction in Japan for ventilation and perfusion analysis. Single photon emission CT can be used to assess ventilation-perfusion (VË/QË) mismatch in pulmonary vascular diseases and COPD. PET/CT VË/QË imaging has also been demonstrated using "Galligas". Both ultrasound and EIT can detect pulmonary edema caused by acute respiratory distress syndrome. Familiarity with these functional imaging techniques will enable clinicians to utilize these systems in clinical practice.
Assuntos
Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodosRESUMO
A 60-year-old man was noted to have an elevated lesion in the right mainstem bronchus on chest computed tomography (CT) during his annual medical checkup 3 years previously. The lesion had gradually increased in size. FDG-PET showed no accumulation. Bronchoscopy revealed 5 nodular smooth surface protrusions on the ventral surface of the right mainstem bronchus, with the largest lesion that measured 5 mm in diameter. Biopsy showed diffuse infiltration of small lymphocytes, positive for CD20 and subsequently diagnosed with mucosa-associated lymphoid tissue (MALT) lymphoma. The lesions disappeared on chest CT after radiotherapy, and no recurrence has been observed after 5 years. We reviewed 48 cases of endobronchial MALT lymphoma in the literature and provided a comprehensive review of the literature to date including our case.
RESUMO
BACKGROUND: Numerous studies investigated patients with IPF; however, only a few examined patients with idiopathic interstitial pneumonias (IIPs). METHODS: The Japanese Idiopathic Interstitial Pneumonias (JIPS) Registry, which was initiated in December 2016, is a multicenter prospective observational study of patients newly diagnosed with IIPs from 86 facilities treating ILDs. The plan is to enroll more than 600 new patients during the 2-year enrolment period and to follow their progress for 3 years after the last case enrolment. If additional consent is obtained, the study will continue for another 2 years. Research questions mainly focus on identifying the frequency by IIP classification, patient background, and diagnostic methods during enrolment, survival, acute exacerbation rate, changes in high-resolution CT imaging, forced vital capacity, and interstitial pneumonia markers over time. Other research questions, including those regarding disease behavior in patients with progressive fibrosing-ILD and new biomarkers associated with genetic predispositions, will be investigated. DISCUSSION: The JIPS Registry will provide a comprehensive description of the disease progression, prognosis, treatment status, new biomarkers, and validity of guidelines and central multidisciplinary decisions for IPF and similar diseases that can be differentiated from IPF among IIPs. ETHICS AND DISSEMINATION: Ethical approval was obtained from the institutional review board of Kanagawa Cardiovascular and Respiratory Center (KCRC-16-0005), and that of Jichi Medical University approved the biobank part (I18-005). Results will be published in peer-reviewed journals and will be presented at national and international conferences. TRIAL REGISTRATION: ClinTrials.gov Registry (NCT03041623, first posted on February 3, 2017).
Assuntos
Pneumonias Intersticiais Idiopáticas , Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Humanos , Biomarcadores , Pneumonias Intersticiais Idiopáticas/diagnóstico , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/epidemiologia , Fibrose Pulmonar Idiopática/terapia , Pulmão , Sistema de Registros , JapãoRESUMO
OBJECTIVES: The aim of the present study was to longitudinally evaluate job stress and burnout before and after the third wave of in Japan and identify transitional changes in the mental health status of a cohort of employees at a coronavirus disease 2019 (COVID-19)-dedicated hospital. METHODS: The same surveys were conducted in October 2020 and March 2021. 151 subjects who responded to both surveys were included. The Maslach Burnout Inventory-General Survey was used to evaluate burnout. Multiple logistic regression analyses were performed to determine odds ratios for factors associated with burnout using a non-burnout group as a reference. RESULTS: In the cohort, 31.1% of employees showed dropout intention and 13.2% of employees were experiencing burnout in March 2021. Hospital workers were more motivated by a sense of contribution and accomplishment, which could balance increased exhaustion in March 2021. The following factors associated with burnout remained to be solved: self-quarantine, unfavorable patient prognosis, poor communication of information, lack of sleep in comparison to the pre-COVID-19 period, and desire for good communication of information. CONCLUSION: It is important to continuously evaluate the mental health status of employees and to provide targeted prevention and intervention in order to mitigate psychological distress and avoid burnout and resignation.
Assuntos
Esgotamento Profissional , COVID-19 , Estresse Ocupacional , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , COVID-19/epidemiologia , Ajustamento Emocional , Hospitais , Humanos , Japão/epidemiologia , Estresse Ocupacional/epidemiologia , PandemiasRESUMO
We experienced a case of silent Coronavirus disease 2019 (COVID-19) pneumonia that was found by an optional chest computed tomography (CT) scan during a health check. A 62-year-old man with a present medical history of hypertension visited the health screening center at Tokai University Tokyo Hospital on August 7th, 2020. Prior to entry into the hospital, his body temperature was measured and his history was obtained (called 'COVID-19 triage'), but there were no remarkable findings. Subsequently, patchy ground glass opacities were observed with peripheral distribution in bilateral multiple lobes. Based on this finding COVID-19 pneumonia was highly suspected. Subsequently, a PCR test was positive for COVID-19. Even in health check settings, we should be aware of possible encounters with COVID-19 infections. The high risk of silent spread plays a significant role in the ongoing pandemic. Chest CT scans, which can efficiently identify silent COVID-19 pneumonia, should be performed earlier during health check examinations, at least before gastroendoscopy, which causes significant droplet dispersion. Health check examination providers should not cancel or postpone health checks; rather, it is necessary for them to provide health check examinees with a safe environment with minimal delay in access to recommended health care services.
Assuntos
COVID-19 , COVID-19/diagnóstico por imagem , Humanos , Pulmão , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2 , Tóquio , Tomografia Computadorizada por Raios X/métodosRESUMO
A 44-year-old man developed coronavirus disease 2019 (COVID-19) pneumonia during immunochemotherapy consisting of carboplatin, paclitaxel, and pembrolizumab for non-small cell lung cancer. Low-grade fever, followed by mild hypoxemia, and febrile neutropenia, were observed, and granulocyte colony-stimulating factor (G-CSF) was administered until the recovery of neutropenia, when he developed a high fever, severe hypoxemia, and hypotension accompanied by consolidation in the bilateral lungs. His conditions promptly improved after treatment including hydrocortisone and the primary and metastatic tumors remained regressed for 10 months without further treatment. Post-COVID-19 organizing pneumonia during cancer immunochemotherapy can be aggravated by immune-checkpoint inhibitors and G-CSF.
Assuntos
COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Hipóxia/tratamento farmacológico , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/tratamento farmacológico , MasculinoRESUMO
Nitric oxide (NO) is produced in the body and has been shown to have diverse actions in the abundance of research that has been performed on it since the 1970s, leading to Furchgott, Murad, and Ignarro receiving the Nobel Prize in Physiology or Medicine in 1998. NO is produced by nitric oxide synthase (NOS). NOS is broadly distributed, being found in the nerves, blood vessels, airway epithelium, and inflammatory cells. In asthma, inflammatory cytokines induce NOS activity in the airway epithelium and inflammatory cells, producing large amounts of NO. Measurement of fractional exhaled nitric oxide (FeNO) is a simple, safe, and quantitative method of assessing airway inflammation. The FeNO measurement method has been standardized and, in recent years, this noninvasive test has been broadly used to support the diagnosis of asthma, monitor airway inflammation, and detect asthma overlap in chronic obstructive pulmonary disease (COPD) patients. Since the normal upper limit of FeNO for healthy Japanese adults is 37 ppb, values of 35 ppb or more are likely to be interpreted as a signature of inflammatory condition presenting features with asthma, and this value is used in clinical practice. Research is also underway for clinical application of these measurements in other respiratory diseases such as COPD and interstitial lung disease. Currently, there remains some confusion regarding the significance of these measurements and the interpretation of the results. This statement is designed to provide a simple explanation including the principles of FeNO measurements, the measurement methods, and the interpretation of the measurement results.
Assuntos
Asma/diagnóstico , Testes Respiratórios/métodos , Doenças Pulmonares Intersticiais/diagnóstico , Óxido Nítrico/análise , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Asma/complicações , Biomarcadores/análise , Espasmo Brônquico/diagnóstico , Bronquiolite Obliterante/diagnóstico , Feminino , Humanos , Inflamação , Masculino , Doença Pulmonar Obstrutiva Crônica/complicaçõesRESUMO
HAPE (High Altitude Pulmonary Edema) is a serious and fatal disease in mountains. Early diagnosis and immediate descent are important for successful treatment. One of the authors (GS), who was healthy and a well trained climber, participated in the expedition to K2 (8611 m) in 2006 and developed HAPE. Under the severe environmental condition, it was difficult to evaluate his condition in its early stage. The earliest symptoms were nonspecific for HAPE as reported in many papers. Neither had he suffered from HAPE on the previous expeditions. These facts probably delayed the diagnosis in spite of its typical onset. This is a rare case report by a medical doctor who suffered from HAPE. The present case may remind the climbers of the difficulties in diagnosing HAPE on a mountain.
Assuntos
Doença da Altitude/complicações , Montanhismo , Edema Pulmonar/etiologia , Adulto , Expedições , Humanos , Masculino , Oxigênio/metabolismo , Paquistão , Pressão ParcialRESUMO
It is not clear whether blood hemoglobin concentration ([Hb]) increases with an increase in the exposure period of intermittent hypoxia (IHx) and reaches a constant level. Furthermore, it is not known whether plasma erythropoietin concentration ([EPO]) also increases with an increase in the exposure period. Using a rat model, first, we evaluated changes in [EPO] every hour after single exposure of 10% O(2) for 120 min in order to determine a peak level of [EPO]. Second, we evaluated the effect of IHx of 10% O(2), 120 min/day for 0 (control), 1, 2, 3, 4, 6 and 8 weeks on [Hb], arterial blood pressure (BP), heart rate (HR), arterial blood gases (ABGs) and [EPO]. [EPO] increased after cessation of the single hypoxic exposure, reached a peak at 1 h, and decreased gradually to the control levels within 18 h. IHx of 10% O(2), 120 min/day, produced a time-dependent increase in [Hb], and [Hb] reached a constant level after the exposure for 6 weeks. BP increased after the exposure for 4 weeks and remained elevated. There was no significant difference in HR and ABGs. [EPO] increased significantly and remained elevated at the same level for 1-3 weeks, however, the peak level of [EPO] declined markedly after [Hb] reached a constant level.
Assuntos
Eritropoetina/metabolismo , Hipóxia/complicações , Policitemia/complicações , Animais , Pressão Sanguínea/fisiologia , Hemoglobinas/metabolismo , Hipóxia/fisiopatologia , Masculino , Policitemia/fisiopatologia , Ratos , Ratos Sprague-DawleyRESUMO
[Background] In patients with chronic obstructive pulmonary disease (COPD), early lactic acidosis during exercise should be considered as playing a role in the limitation of exercise tolerance. It was hypothesized that the relationship between blood lactate concentrations (LA) and tissue oxygenation index (TOI) is available for the prediction of aerobic capacity of skeletal muscle. [Methods] Changes of LA and TOI in the vastus lateralis muscle were measured during incremental cycling exercise in 12 healthy subjects and 4 patients with COPD. The relationship between TOI and LA was examined in 12 healthy subjects and 4 COPD patients, and changes in the relationship were examined at an interval of several years (3.3 +/- 1.0). [Results] (1) From the pattern LA as related to TOI, the healthy subjects were classified into the three groups. Group A (n = 3); LA increased slowly with a decrease in TOI. Group B (n = 3); LA increased steeply after the half point of maximal exercise. Group C (n = 6); LA increased steeply before the half point of maximal exercise. (2) In 3 patients with COPD, the relationship between TOI and LA shifted rightward at the second examination. [Conclusion] The steep increase in LA from the approximate resting value of TOI during exercise suggests that the aerobic capacity of working skeletal muscle decreased.
Assuntos
Teste de Esforço , Saúde , Ácido Láctico/sangue , Músculo Esquelético/metabolismo , Doença Pulmonar Obstrutiva Crônica/sangue , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Oxirredução , Oxigênio/metabolismoRESUMO
Purpose: Patients with chronic obstructive pulmonary disease (COPD) have decreased physical activity (PA) compared with healthy adults. As lower PA is associated with increased mortality, improving PA is an important objective for COPD management. This large-scale, multicenter, non-interventional, cross-sectional study examined the activity status of COPD patients in Japan and explored factors related to PA. Patients and Methods: Outpatients aged ≥40 years with confirmed COPD diagnosis and pulmonary function test data were enrolled. Primary study outcomes were measurement of daily steps (over 14 consecutive days, using an activity monitor), assessment of activity time by activity intensity (using metabolic equivalents [METs]), and evaluation of correlation between PA and patient characteristics. Secondary outcomes included further investigation of the influence of patient characteristics on PA. Results: Data from 417 patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages I (29.5%), II (43.9%), III (23.5%), and IV (3.1%) were evaluated. Median (Q1, Q3) daily step count was 3440.8 (1831.3, 5709.3). Median (Q1, Q3) durations of PA at ≥3 (moderate-to-vigorous) and ≥2 METs (light-to-vigorous) were 18.7 (6.5, 41.3) and 186.9 (126.9, 259.2) minutes, respectively. For >30% of patients, time spent in ≥3 METs activity was ≤10 minutes. Unemployment was significantly correlated with reduced activity time (≥3 and ≥2 METs) and step count. Severe GOLD stage was significantly correlated with reduced activity time (≥3 and ≥2 METs). High modified Medical Research Council (mMRC) dyspnea score was significantly correlated with reduced activity time (≥3 METs) and step count. Patients tended to overestimate the time spent in activities requiring ≥2 METs in their subjective reports compared with activity monitor measurements. Conclusion: Reduced PA was observed in the Japanese COPD patients with the majority of them being GOLD stage I/II. Employment status, GOLD stage, and mMRC dyspnea score could help identify patients at risk of reduced PA. Clinical Trial Registration: NCT03642613 (ClinicalTrials.gov); UMIN000032962 (UMIN-CTR, umin.ac.jp).