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BackgroundComputed tomography (CT) phenotypic characterization helps in understanding the clinical diversity of chronic obstructive pulmonary disease (COPD) patients, but its clinical relevance and its relationship with functional features are not clarified. Volumetric capnography (VC) uses the principle of gas washout and analyzes the pattern of CO2 elimination as a function of expired volume. The main variables analyzed were end-tidal concentration of carbon dioxide (ETCO2), Slope of phase 2 (Slp2), and Slope of phase 3 (Slp3) of capnogram, the curve which represents the total amount of CO2 eliminated by the lungs during each breath.ObjectiveTo investigate, in a group of patients with severe COPD, if the phenotypic analysis by CT could identify different subsets of patients, and if there was an association of CT findings and functional variables.Subjects and methodsSixty-five patients with COPD Gold III–IV were admitted for clinical evaluation, high-resolution CT, and functional evaluation (spirometry, 6-minute walk test [6MWT], and VC). The presence and profusion of tomography findings were evaluated, and later, the patients were identified as having emphysema (EMP) or airway disease (AWD) phenotype. EMP and AWD groups were compared; tomography findings scores were evaluated versus spirometric, 6MWT, and VC variables.ResultsBronchiectasis was found in 33.8% and peribronchial thickening in 69.2% of the 65 patients. Structural findings of airways had no significant correlation with spirometric variables. Air trapping and EMP were strongly correlated with VC variables, but in opposite directions. There was some overlap between the EMP and AWD groups, but EMP patients had signicantly lower body mass index, worse obstruction, and shorter walked distance on 6MWT. Concerning VC, EMP patients had signicantly lower ETCO2, Slp2 and Slp3. Increases in Slp3 characterize heterogeneous involvement of the distal air spaces, as in AWD.ConclusionVisual assessment and phenotyping of CT in COPD patients is feasible and may help identify functional and clinically different subsets of patients. VC may provide useful information about the heterogeneous involvement of lung structures in COPD.

Bronchiectasis is a condition that has been increasingly diagnosed by chest HRCT. In the literature, bronchiectasis is divided into bronchiectasis secondary to cystic fibrosis and bronchiectasis not associated with cystic fibrosis, which is termed non-cystic fibrosis bronchiectasis. Many causes can lead to the development of bronchiectasis, and patients usually have chronic airway symptoms, recurrent infections, and CT abnormalities consistent with the condition. The first international guideline on the diagnosis and treatment of non-cystic fibrosis bronchiectasis was published in 2010. In Brazil, this is the first review document aimed at systematizing the knowledge that has been accumulated on the subject to date. Because there is insufficient evidence on which to base recommendations for various treatment topics, here the decision was made to prepare an expert consensus document. The Brazilian Thoracic Association Committee on Respiratory Infections summoned 10 pulmonologists with expertise in bronchiectasis in Brazil to conduct a critical assessment of the available scientific evidence and international guidelines, as well as to identify aspects that are relevant to the understanding of the heterogeneity of bronchiectasis and to its diagnostic and therapeutic management. Five broad topics were established (pathophysiology, diagnosis, monitoring of stable patients, treatment of stable patients, and management of exacerbations). After this subdivision, the topics were distributed among the authors, who conducted a nonsystematic review of the literature, giving priority to major publications in the specific areas, including original articles, review articles, and systematic reviews. The authors reviewed and commented on all topics, producing a single final document that was approved by consensus.

Community-acquired pneumonia (CAP) is the leading cause of death worldwide. Despite the vast diversity of respiratory microbiota, Streptococcus pneumoniae remains the most prevalent pathogen among etiologic agents. Despite the significant decrease in the mortality rates for lower respiratory tract infections in recent decades, CAP ranks third as a cause of death in Brazil. Since the latest Guidelines on CAP from the Sociedade Brasileira de Pneumologia e Tisiologia (SBPT, Brazilian Thoracic Association) were published (2009), there have been major advances in the application of imaging tests, in etiologic investigation, in risk stratification at admission and prognostic score stratification, in the use of biomarkers, and in the recommendations for antibiotic therapy (and its duration) and prevention through vaccination. To review these topics, the SBPT Committee on Respiratory Infections summoned 13 members with recognized experience in CAP in Brazil who identified issues relevant to clinical practice that require updates given the publication of new epidemiological and scientific evidence. Twelve topics concerning diagnostic, prognostic, therapeutic, and preventive issues were developed. The topics were divided among the authors, who conducted a nonsystematic review of the literature, but giving priority to major publications in the specific areas, including original articles, review articles, and systematic reviews. All authors had the opportunity to review and comment on all questions, producing a single final document that was approved by consensus.

This study was designed to use volumetric capnography to evaluate the breathing pattern and ventilation inhomogeneities in patients with chronic sputum production and bronchiectasis and to correlate the phase 3 slope of the capnographic curve to spirometric measurements. Twenty-four patients with cystic fibrosis (CF) and 21 patients with noncystic fibrosis idiopathic bronchiectasis (BC) were serially enrolled. The diagnosis of cystic fibrosis was based on the finding of at least two abnormal sweat chloride concentrations (iontophoresis sweat test). The diagnosis of bronchiectasis was made when the patient had a complaint of chronic sputum production and compatible findings at high-resolution computed tomography (HRCT) scan of the thorax. Spirometric tests and volumetric capnography were performed. The 114 subjects of the control group for capnographic variables were nonsmoker volunteers, who had no respiratory symptoms whatsoever and no past or present history of lung disease. Compared with controls, patients in CF group had lower SpO(2) (P < 0.0001), higher respiratory rates (RR) (P < 0.0001), smaller expiratory volumes normalized for weight (V(E)/kg) (P < 0.028), smaller expiratory times (Te) (P < 0.0001), and greater phase 3 Slopes normalized for tidal volume (P3Slp/V(E)) (P < 0.0001). Compared with controls, patients in the BC group had lower SpO(2) (P < 0.0001), higher RR (P < 0.004), smaller V(E)/kg (P < 0.04), smaller Te (P < 0.007), greater P3Slp/V(E) (P < 0.0001), and smaller VCO(2) (P < 0.0002). The pooled data from the two patient groups compared with controls showed that the patients had lower SpO(2) (P < 0.0001), higher RR (P < 0.0001), smaller V(E)/kg (P < 0.05), smaller Te (P < 0.0001), greater P3Slp/V(E) (P < 0.0001), and smaller VCO(2) (P < 0.0003). All of the capnographic and spirometric variables evaluated showed no significant differences between CF and BC patients. Spirometric data in this study reveals that the patients had obstructive defects with concomitant low vital capacities and both groups had very similar abnormalities. The capnographic variables in the patient group suggest a restrictive respiratory pattern (greater respiratory rates, smaller expiratory times and expiratory volumes, normal peak expiratory flows). Both groups of patients showed increased phase III slopes compared with controls, which probably indicates the presence of diffuse disease of small airways in both conditions leading to inhomogeneities of ventilation.

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Neuromuscular diseases affect alveolar air exchange and therefore cause chronic respiratory failure. The onset of respiratory failure can be acute, as in traumas, or progressive (slow or rapid), as in amyotrophic lateral sclerosis, muscular dystrophies, diseases of the myoneural junction, etc. Respiratory muscle impairment also affects cough efficiency and, according to the current knowledge regarding the type of treatment available in Brazil to these patients, it can be said that the high rates of morbidity and mortality in these individuals are more often related to the fact that they cough inefficiently rather than to the fact that they ventilate poorly. In this review, with the objective of presenting the options of devices available to support and substitute for natural ventilation in patients with neuromuscular diseases, we have compiled a brief history of the evolution of orthopedic braces and prostheses used to aid respiration since the end of the 19th century. In addition, we highlight the elements that are fundamental to the diagnosis of alveolar hypoventilation and of failure of the protective cough mechanism: taking of a clinical history; determination of peak cough flow; measurement of maximal inspiratory and expiratory pressures; spirometry in two positions (sitting and supine); pulse oximetry; capnography; and polysomnography. Furthermore, the threshold values available in the literature for the use of nocturnal ventilatory support and for the extension of this support through the daytime period are presented. Moreover, the maneuvers used to increase cough efficiency, as well as the proper timing of their introduction, are discussed.

Pulmonary arterial hypertension (PAH) impairs exercise tolerance and daily physical activity (PA). Aside from the hemodynamic limitations, physical, cognitive and emotional factors may play a relevant and as yet unexplored role. We investigated whether there is an association between the PA level and psychological disorders, health-related quality of life, and daily activities. We also searched for an association of the PA level with clinical factors and functional capacity. This was an analytical, cross-sectional, observational study conducted in a Brazilian University Hospital. Twenty stable PAH subjects wore an accelerometer for a week and completed an activity diary. They answered the quality of life questionnaire (SF-36), as well as the anxiety and depression scale (HADS), and the Manchester Respiratory Activities of Daily Living questionnaire (MRADL). Transthoracic echocardiography, the 6-Minute walk test (6MWT), the 1-minute sit-to-stand test (STST), and spirometry were performed. For statistical analysis we used Chi-square tests or Fisher's test as appropriate and the Mann-Whitney test to compare numerical values between two groups. The relationship between the parameters was assessed using the Spearman correlation test. The mean age was 44.3 years, 80% were women, 80% had idiopathic PAH, and 20% had connective tissue disease . The mean daily step count was 4,280 ± 2,351, and the mean activity time was 41.6 ± 19.3 minutes. The distance covered (6MWT) was 451.5 m, and the number of movements (1-STST) was 23.8. Thirty percent scored positive for anxiety, and 15% for depression (HADS). There was a significant correlation between accelerometer data and walking distance (6MWT), number of movements (1-STST), level of daily physical activity (MRADL), and depression symptoms. Our findings support the hypothesis that other aspects beyond physical and hemodynamic ones might impact the daily physical activity of patients with PAH.