Correlations between volumetric capnography and automated quantitative computed tomography analysis in patients with severe COPD (original) (raw)
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International journal of chronic obstructive pulmonary disease, 2016
Computed 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. To 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. Sixty-five patients with COPD Gold III-IV were admitted for clinical evaluation, high-resolution CT, and functional evaluation (spirometry, 6-minute walk ...
Assessment of COPD severity by computed tomography: correlation with lung functional testing
Clinical Imaging, 2010
CT scans of 474 patients with suspected chronic obstructive pulmonary disease (COPD) were retrospectively evaluated by automated software. There was a correlation between the total lung capacity (TLC) and the total lung volume (TLV) (r=.675, Pb.001), between the TLC and the total emphysema volume (r=.571, Pb.001), as well as between the TLC and the emphysema index (r=.532, Pb.001), respectively. The correlation between the TLC and the TLV was dependent on the COPD severity according to the Global Initiative for Chronic Obstructive Lung Disease classification (χ 2 =6.3079, P=.043). The TLC allows a prediction of clinical illness severity.
The Indian journal of radiology & imaging
Both emphysematous destruction of lung parenchyma and airway remodeling is thought to contribute to airflow limitation in cases of chronic obstructive pulmonary disease (COPD). To evaluate the value of quantitative computed tomography (QCT) parameters of emphysema and airway disease with disease severity in patients with COPD. We prospectively studied 50 patients with COPD, which included nonsmokers and patients with different degrees of cumulative smoking exposure. Three QCT parameters namely LAA% (low attenuation area percentage), WA% (Wall area percentage), and pi10 were calculated as per the standard technique. Forced expiratory volume in 1 s (FEV1), BODE score, and MMRC dyspnea scale were used as measures of disease severity. FEV1 was inversely and significantly associated with all three QCT parameters. Receiver operated characteristic curves in prediction of GOLD class 3 COPD yielded cut-off values of 12.2, 61.45, and 3.5 for LAA%, WA%, and pi10, respectively, with high sensit...
The Role of Chest Computed Tomography in the Evaluation and Management of the Patient with COPD
American journal of respiratory and critical care medicine, 2017
Chronic obstructive pulmonary disease (COPD) exhibits significant heterogeneity in clinical presentation and rate of disease progression, owing at least in part to differing underlying morphologic abnormalities. Symptom assessment and spirometry have traditionally been used to determine disease severity and guide management. However, chest computed tomography (CT) is a widely available and increasingly used imaging modality that can provide additional insight into structural and pathophysiologic pulmonary parameters. While chest CT is not currently recommended as part of the routine evaluation for COPD beyond aiding with advanced therapy decision making in severe disease, the expanding use of CT now demands that clinicians understand how to treat relevant information that becomes available. Emphysema, airway disease, air trapping and pulmonary vascular abnormalities have all been associated with a number of important outcomes, including respiratory symptoms, COPD exacerbations and m...
Recent Advances in Computed Tomography Imaging in Chronic Obstructive Pulmonary Disease
Annals of the American Thoracic Society, 2017
Lung imaging is increasingly being used to diagnose, quantify, and phenotype chronic obstructive pulmonary disease (COPD). Although spirometry is the gold standard for the diagnosis of COPD and for severity staging, the role of computed tomography (CT) imaging has expanded in both clinical practice and research. COPD is a heterogeneous disease with considerable variability in clinical features, radiographic disease, progression, and outcomes. Recent studies have examined the utility of CT imaging in enhancing diagnostic certainty, improving phenotyping, predicting disease progression and prognostication, selecting patients for intervention, and also in furthering our understanding of the complex pathophysiology of this disease. Multiple CT metrics show promise for use as imaging biomarkers in COPD.
The benefit of expiratory phase quantitative CT densitometry in the early diagnosis of copd
Diagnostic and Interventional Radiology, 2011
A s a progressive illness, chronic obstructive pulmonary disease (COPD) is a public health problem that significantly increases the rate of mortality and morbidity and is one of the leading causes of death (1). Chronic air flow limitation in COPD is caused by a mixture of a small-airway disease (obliterative bronchiolitis) and parenchymal destruction (emphysema), the relative contributions of which vary from person to person (2). A pulmonary function test (PFT) is the method most commonly used to detect airway obstruction (3). However, PFT is usually inadequate for the prompt diagnosis of people at risk for COPD (2). Inflammatory markers are also insufficient for diagnosis (4). Currently, computed tomography (CT) scanning is accepted as a method that is more sensitive than PFT for use in diagnosing changes in the pulmonary parenchyma, particularly emphysematous changes in a person with COPD (3, 5). In the literature, the quantitative CT densitometry evaluation is preferred to visual assessment (6) and is accepted as a COPD diagnostic method (7, 8) that can be used to help differentiate COPD phenotypes (emphysema-predominant, airway-predominant, and mixed) (3). The previous studies were inconclusive as to whether inspiratory CT or expiratory CT is better for evaluating the severity of COPD and whether one or the other was better at identifying emphysematous changes (9, 10). We aimed to compare the inspiratory and expiratory quantitative CT densitometry data of healthy volunteers, patients with COPD risk, and COPD patients to investigate the contribution of quantitative CT densitometry in the early diagnosis of COPD. Materials and methods In this study, we evaluated 14 healthy male volunteers (Group I, control group), 12 male patients at risk for COPD (Group II), and 13 male COPD patients (Group III). COPD was diagnosed according to the criteria established by the Global Initiative for Chronic Obstructive Lung Diseases (GOLD) (2) and by the use of spirometry testing, consistent with irreversible expiratory airflow obstruction. The inclusion criteria were male sex, age of 40 to 60 years, and a body mass index (BMI) below 30 kg/m 2. The inclusion criterion for the control group was a forced expiratory volume in 1 s/forced vital capacity (FEV 1 /FVC) of >70%. Written informed consent was obtained from all participants before the procedure. The experimental protocol was approved by the Ethical Committee of Zonguldak Karaelmas University. Patients with non-COPD pulmonary diseases, such as clinically-diagnosed or suspected cardiac history, bronchial asthma, bronchiectasis, collagen tissue disease, acute infection, and malignancy were excluded from the COPD group. Participants were excluded from Groups I and II if they were known to have pulmonary disease and if their forced
Forced expiratory capnography and chronic obstructive pulmonary disease (COPD)
Journal of Breath Research, 2013
This report proposes a potentially sensitive and simple physiological method to detect early changes and to follow disease progression in obstructive pulmonary disease (COPD) based upon the usual pulmonary function test. Pulmonary function testing is a simple, although relatively insensitive, method to detect and follow COPD. As a proof-of-concept, we have examined the slope of the plateau for carbon dioxide during forced expiratory capnography in healthy (n=10) and COPD subjects (n=10). We compared the change in the rate of exhalation of carbon dioxide over time as a marker of heterogeneous ventilation of the lung. All subjects underwent pulmonary function testing, body-plethysmography, and forced exhalation capnography. The subjects with COPD also underwent high-resolution computed tomography of the chest. Regression lines were fitted to the slopes of the forced exhalation capnogram curves. There was no difference in the mean levels of exhaled carbon dioxide between the COPD and the healthy groups (p>0.48). We found a significant difference in the mean slope of the forced exhalation capnogram for the COPD subjects compared to the healthy subjects (p=0.01). Most important, for the COPD subjects, there was a significant positive correlation between the slope of the forced exhaled capnogram and a defined radiodensity measurement of the lung by high-resolution computed tomography (r 2 =0.49, p=0.02). The slope of the forced exhalation capnogram may be a simple way to determine physiological changes in the lungs in patients with COPD that are not obtainable with standard pulmonary function tests. Forced exhalation capnography would be of great clinical benefit if it can identify early disease changes and at-risk individuals.
Utility of Chest Computed Tomography for Chronic Obstructive Pulmonary Disease Patients
The Indian Journal of Chest Diseases and Allied Sciences
Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable disease that is characterized by persistent respiratory symptoms and airflow limitation that is due to airway and/or alveolar abnormalities usually caused by significant exposure to noxious particles or gases and influenced by host factors including abnormal lung development. 1 Currently, the diagnosis of COPD is based on the clinical history of the patient along with a post-bronchodilator forced expiratory volume in one second/forced vital capacity (FEV 1 /FVC) ratio lower than 0.70 on spirometry. Even though spirometry is considered the most valuable tool in diagnosing COPD, it lacks in certain aspects such as covering the morphological analysis of the disease and correlating between the lesions and lung function. Also, spirometry usually becomes abnormal pretty late in the disease evolution, and hence, is unable to identify early and pre-COPD patients leading to delayed diagnosis. Chest computed tomography (CT) scan provides in vivo assessment of organ structure and can prove itself to be a useful tool to provide additional information about parenchymal remodeling, airway dilation, and vascular calcification. This, in turn, can be useful to not only detect and stratify the severity of the disease but can also to predict its clinical course. We must consider the utility of CT scan to offer impactful therapy for what is found in those images. However, does this additional information really makes a difference in the management of COPD patients? Can this information be obtained using inexpensive and easy methods (such as spirometry and questionnaires)? Does this additional information really justify the expense of radiation exposure? This article highlights the utility, limitations, and future prospects of adding a chest CT scan as a routine investigation in patients with COPD.