scholarly journals Tidal volume (TV) post-process obtained with electrical impedance tomography on a group of chronic obstructive pulmonary disease (COPD) patients. Use of adjust equations

2010 ◽  
Vol 224 ◽  
pp. 012030
Author(s):  
Marco Balleza ◽  
Daniel Anton ◽  
Pere Casan ◽  
Pere Riu
2016 ◽  
Vol 311 (1) ◽  
pp. L8-L19 ◽  
Author(s):  
Barbara Vogt ◽  
Zhanqi Zhao ◽  
Peter Zabel ◽  
Norbert Weiler ◽  
Inéz Frerichs

Patients with obstructive lung diseases commonly undergo bronchodilator reversibility testing during examination of their pulmonary function by spirometry. A positive response is defined by an increase in forced expiratory volume in 1 s (FEV1). FEV1 is a rather nonspecific criterion not allowing the regional effects of bronchodilator to be assessed. We employed the imaging technique of electrical impedance tomography (EIT) to visualize the spatial and temporal ventilation distribution in 35 patients with chronic obstructive pulmonary disease at baseline and 5, 10, and 20 min after bronchodilator inhalation. EIT scanning was performed during tidal breathing and forced full expiration maneuver in parallel with spirometry. Ventilation distribution was determined by EIT by calculating the image pixel values of FEV1, forced vital capacity (FVC), tidal volume, peak flow, and mean forced expiratory flow between 25 and 75% of FVC. The global inhomogeneity indexes of each measure and histograms of pixel FEV1/FVC values were then determined to assess the bronchodilator effect on spatial ventilation distribution. Temporal ventilation distribution was analyzed from pixel values of times needed to exhale 75 and 90% of pixel FVC. Based on spirometric FEV1, significant bronchodilator response was found in 17 patients. These patients exhibited higher postbronchodilator values of all regional EIT-derived lung function measures in contrast to nonresponders. Ventilation distribution was inhomogeneous in both groups. Significant improvements were noted for spatial distribution of pixel FEV1 and tidal volume and temporal distribution in responders. By providing regional data, EIT might increase the diagnostic and prognostic information derived from reversibility testing.


2019 ◽  
Vol 127 (5) ◽  
pp. 1441-1452 ◽  
Author(s):  
Stephen Milne ◽  
Jacqueline Huvanandana ◽  
Chinh Nguyen ◽  
Joseph M. Duncan ◽  
David G. Chapman ◽  
...  

Pulmonary electrical impedance tomography (EIT) is a functional imaging technique that allows real-time monitoring of ventilation distribution. Ventilation heterogeneity (VH) is a characteristic feature of chronic obstructive pulmonary disease (COPD) and has previously been quantified using features derived from tidal variations in the amplitude of the EIT signal. However, VH may be better described by time-based metrics, the measurement of which is made possible by the high temporal resolution of EIT. We aimed 1) to quantify VH using novel time-based EIT metrics and 2) to determine the physiological relevance of these metrics by exploring their relationships with complex lung mechanics measured by the forced oscillation technique (FOT). We performed FOT, spirometry, and tidal-breathing EIT measurements in 11 healthy controls and 9 volunteers with COPD. Through offline signal processing, we derived 3 features from the impedance-time ( Z- t) curve for each image pixel: 1) tE, mean expiratory time; 2) PHASE, mean time difference between pixel and global Z- t curves; and 3) AMP, mean amplitude of Z- t curve tidal variation. Distribution was quantified by the coefficient of variation (CV) and the heterogeneity index (HI). Both CV and HI of the tE and PHASE features were significantly increased in COPD compared with controls, and both related to spirometry and FOT resistance and reactance measurements. In contrast, distribution of the AMP feature showed no relationships with lung mechanics. These novel time-based EIT metrics of VH reflect complex lung mechanics in COPD and have the potential to allow real-time visualization of pulmonary physiology in spontaneously breathing subjects. NEW & NOTEWORTHY Pulmonary electrical impedance tomography (EIT) is a real-time imaging technique capable of monitoring ventilation with exquisite temporal resolution. We report novel, time-based EIT measurements that not only demonstrate ventilation heterogeneity in chronic obstructive pulmonary disease (COPD), but also reflect oscillatory lung mechanics. These EIT measurements are noninvasive, radiation-free, easy to obtain, and provide real-time visualization of the complex pathophysiology of COPD.


2020 ◽  
Vol 29 (2) ◽  
pp. 864-872
Author(s):  
Fernanda Borowsky da Rosa ◽  
Adriane Schmidt Pasqualoto ◽  
Catriona M. Steele ◽  
Renata Mancopes

Introduction The oral cavity and pharynx have a rich sensory system composed of specialized receptors. The integrity of oropharyngeal sensation is thought to be fundamental for safe and efficient swallowing. Chronic obstructive pulmonary disease (COPD) patients are at risk for oropharyngeal sensory impairment due to frequent use of inhaled medications and comorbidities including gastroesophageal reflux disease. Objective This study aimed to describe and compare oral and oropharyngeal sensory function measured using noninstrumental clinical methods in adults with COPD and healthy controls. Method Participants included 27 adults (18 men, nine women) with a diagnosis of COPD and a mean age of 66.56 years ( SD = 8.68). The control group comprised 11 healthy adults (five men, six women) with a mean age of 60.09 years ( SD = 11.57). Spirometry measures confirmed reduced functional expiratory volumes (% predicted) in the COPD patients compared to the control participants. All participants completed a case history interview and underwent clinical evaluation of oral and oropharyngeal sensation by a speech-language pathologist. The sensory evaluation explored the detection of tactile and temperature stimuli delivered by cotton swab to six locations in the oral cavity and two in the oropharynx as well as identification of the taste of stimuli administered in 5-ml boluses to the mouth. Analyses explored the frequencies of accurate responses regarding stimulus location, temperature and taste between groups, and between age groups (“≤ 65 years” and “> 65 years”) within the COPD cohort. Results We found significantly higher frequencies of reported use of inhaled medications ( p < .001) and xerostomia ( p = .003) in the COPD cohort. Oral cavity thermal sensation ( p = .009) was reduced in the COPD participants, and a significant age-related decline in gustatory sensation was found in the COPD group ( p = .018). Conclusion This study found that most of the measures of oral and oropharyngeal sensation remained intact in the COPD group. Oral thermal sensation was impaired in individuals with COPD, and reduced gustatory sensation was observed in the older COPD participants. Possible links between these results and the use of inhaled medication by individuals with COPD are discussed.


2020 ◽  
Vol 24 (4) ◽  
pp. 80-86
Author(s):  
V. I. Trofimov ◽  
D. Z. Baranov

BACKGROUND: a comparative analysis of laboratory and instrumental tests at patients with bronchial obstructive diseases seems very actual due to the wide prevalence of these diseases. THE AIM: to evaluate characteristics of spirometry as well as allergic (total IgE, sputum eosinophils) and infectious (blood and sputum leucocytes, ESR, CRP, fibrinogen) inflammation markers at patients with bronchial obstructive diseases. PATIENTS AND METHODS: 104 case histories of patients with bronchial asthma, chronic obstructive pulmonary disease and overlap were analyzed including age, duration of smoking (pack-years), laboratory (clinical blood test, biochemical blood test, general sputum analysis, sputum culture) and instrumental (spirometry, body plethysmography, echocardiography) tests. Data were processed statistically with non-parametric methods. RESULTS: COPD patients were older than other groups’ patients, had the highest pack-years index. ACO patients were marked with maximal TLC and Raw, minimal FEV1, FEF25-75, FEV1/FVC. Patients with COPD had the highest inflammation markers (leucocyte count, CRP, fibrinogen). CONCLUSION: high active inflammation may cause severe lower airways possibility disorders at patients with COPD. Data related to a possible role of K. pneumoniaе in the pathogenesis of eosinophilic inflammation in lower airways are of significant interest. Patients with ACO occupy an intermediate position between asthma and COPD patients based on clinical and functional features.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xiaoman Zhou ◽  
Yunjun Zhang ◽  
Yutian Zhang ◽  
Quanni Li ◽  
Mei Lin ◽  
...  

Abstract Objective Chronic obstructive pulmonary disease (COPD) is a complicated multi-factor, multi-gene disease. Here, we aimed to assess the association of genetic polymorphisms in LINC01414/ LINC00824 and interactions with COPD susceptibility. Methods Three single nucleotide polymorphisms (SNPs) in LINC01414/LINC00824 was genotyped by Agena MassARRAY platform among 315 COPD patients and 314 controls. Logistic analysis adjusted by age and gender were applied to estimate the genetic contribution of selected SNPs to COPD susceptibility. Results LINC01414 rs699467 (OR = 0.73, 95% CI 0.56–0.94, p = 0.015) and LINC00824 rs7815944 (OR = 0.56, 95% CI 0.31–0.99, p = 0.046) might be protective factors for COPD occurrence, while LINC01414 rs298207 (OR = 2.88, 95% CI 1.31–6.31, p = 0.008) risk-allele was related to the increased risk of COPD in the whole population. Rs7815944 was associated with the reduced risk of COPD in the subjects aged > 70 years (OR = 0.29, p = 0.005). Rs6994670 (OR = 0.57, p = 0.007) contribute to a reduced COPD risk, while rs298207 (OR = 7.94, p = 0.009) was related to a higher susceptibility to COPD at age ≤ 70 years. Rs298207 (OR = 2.54, p = 0.043) and rs7815944 (OR = 0.43, p = 0.028) variants was associated COPD risk among males. Rs7815944 (OR = 0.16, p = 0.031) was related to the reduced susceptibility of COPD in former smokers. Moreover, the association between rs298207 genotype and COPD patients with dyspnea was found (OR = 0.50, p = 0.016), and rs7815944 was related to COPD patients with wheezing (OR = 0.22, p = 0.008). Conclusion Our finding provided further insights into LINC01414/LINC00824 polymorphisms at risk of COPD occurrence and accumulated evidence for the genetic susceptibility of COPD.


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