Search

Background:Lumacaftor/ivacaftor (LUM/IVA) has shown modest benefits in previous research, but the exact effects in the cystic fibrosis (CF) lung remain unclear. This study aims to offer novel information on the mode of action of the cystic fibrosis transmembrane conductance regulator (CFTR)-modulating drug by assessing lung structure and function using functional respiratory imaging (FRI).Methods:CF patients aged ⩾12 years homozygous for F508del were recruited in an open-label study. Before and after 12 weeks of treatment with LUM/IVA, FRI was used to visualize regional information, such as air trapping, lobar volume and airway wall volume. Secondary outcomes included the CF-CT scoring system, spirometry, the Cystic Fibrosis Questionnaire–Revised (CFQ-R) questionnaire, exercise tolerance and nutritional status.Results:Of the 12 patients enrolled in the study, 11 completed all study visits. Concerning the FRI parameters, hyperinflation of the lung decreased, indicated by a reduction in air trapping and lobar volume at expiration. Also, a decrease in airway wall volume and a redistribution of pulmonary blood volume were noted, which might be related to a decrease in mucus impaction. Airway resistance, airway volume, internal airflow distribution and aerosol deposition pattern did not show significant changes. No significant improvements were found in any of the CF-CT scores or in the spirometric parameters. Other secondary outcomes showed similar results compared with previous research. Correlations at baseline were found between FRI and conventional outcomes, including physical functioning, spirometry and CF-CT scores.Conclusions:LUM/IVA decreased lung hyperinflation in combination with a potential decrease in mucus impaction, which can be related to an improved mucociliary transport. These results indicate that several FRI parameters, reflecting regional and distal lung structures, are more sensitive to changes caused by LUM/IVA than conventional respiratory outcomes.

BACKGROUND: This was a pilot study to analyze the effects of tracheostomy on patient-ventilator asynchronies and respiratory system mechanics. Data were extracted from an ongoing prospective, real-world database that stores continuous output from ventilators and bedside monitors. Twenty adult subjects were on mechanical ventilation and were tracheostomized during an ICU stay: 55% were admitted to the ICU for respiratory failure and 35% for neurologic conditions; the median duration of mechanical ventilation before tracheostomy was 12 d; and the median duration of mechanical ventilation was 16 d. METHODS: We compared patient-ventilator asynchronies (the overall asynchrony index and the rates of specific asynchronies) and respiratory system mechanics (respiratory-system compliance and airway resistance) during the 24 h before tracheostomy versus the 24 h after tracheostomy. We analyzed possible differences in these variables among the subjects who underwent surgical versus percutaneous tracheostomy. To compare longitudinal changes in the variables, we used linear mixed-effects models for repeated measures along time in different observation periods. A total of 920 h of mechanical ventilation were analyzed. RESULTS: Respiratory mechanics and asynchronies did not differ significantly between the 24-h periods before and after tracheostomy: compliance of the respiratory system median (IQR) (47.9 [41.3 – 54.6] mL/cm H(2)O vs 47.6 [40.9 – 54.3] mL/cm H(2)O; P = .94), airway resistance (9.3 [7.5 – 11.1] cm H(2)O/L/s vs 7.0 [5.2 – 8.8] cm H(2)O/L/s; P = .07), asynchrony index (2.0% [1.1 – 3.6%] vs 4.1% [2.3 – 7.6%]; P = .09), ineffective expiratory efforts (0.9% [0.4 – 1.8%] vs 2.2% [1.0 – 4.4%]; P = .08), double cycling (0.5% [0.3 – 1.0%] vs 0.9% [0.5 – 1.9%]; P = .24), and percentage of air trapping (7.6% [4.2 – 13.8%] vs 10.6% [5.9 – 19.2%]; P = .43). No differences in respiratory mechanics or patient-ventilator asynchronies were observed between percutaneous and surgical procedures. CONCLUSIONS: Tracheostomy did not affect patient-ventilator asynchronies or respiratory mechanics within 24 h before and after the procedure

We report manual external chest compression (MECC) as an effective treatment for acute respiratory failure due to severe air trapping. In this retrospective study, we describe our experience with MECC administered to five children suffering from severe air trapping as a consequence of severe asthma or bronchiolitis. These children were admitted to the Pediatric Intensive Care Unit (PICU) with clinical and blood gases parameters compatible with acute respiratory failure. Before intubation MECC was performed. The results of blood gasses before, during, and after MECC showed gradual changes in PCO2 over time indicating the improvement in tidal volume and ventilation. Respiratory failure resolved in all five children within 4 h with no complications. The need for intubation and mechanical ventilation was avoided, and all children were discharged from the PICU within 48 h.

PurposeTo develop a convolutional neural network (CNN)-based deformable lung registration algorithm to reduce computation time and assess its potential for lobar air trapping quantification.Materials and methodsIn this retrospective study, a CNN algorithm was developed to perform deformable registration of lung CT (LungReg) using data on 9118 patients from the COPDGene Study (data collected between 2007 and 2012). Loss function constraints included cross-correlation, displacement field regularization, lobar segmentation overlap, and the Jacobian determinant. LungReg was compared with a standard diffeomorphic registration (SyN) for lobar Dice overlap, percentage voxels with nonpositive Jacobian determinants, and inference runtime using paired t tests. Landmark colocalization error (LCE) across 10 patients was compared using a random effects model. Agreement between LungReg and SyN air trapping measurements was assessed using intraclass correlation coefficient. The ability of LungReg versus SyN emphysema and air trapping measurements to predict Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages was compared using area under the receiver operating characteristic curves.ResultsAverage performance of LungReg versus SyN showed lobar Dice overlap score of 0.91-0.97 versus 0.89-0.95, respectively (P < .001); percentage voxels with nonpositive Jacobian determinant of 0.04 versus 0.10, respectively (P < .001); inference run time of 0.99 second (graphics processing unit) and 2.27 seconds (central processing unit) versus 418.46 seconds (central processing unit) (P < .001); and LCE of 7.21 mm versus 6.93 mm (P < .001). LungReg and SyN whole-lung and lobar air trapping measurements achieved excellent agreement (intraclass correlation coefficients > 0.98). LungReg versus SyN area under the receiver operating characteristic curves for predicting GOLD stage were not statistically different (range, 0.88-0.95 vs 0.88-0.95, respectively; P = .31-.95).ConclusionCNN-based deformable lung registration is accurate and fully automated, with runtime feasible for clinical lobar air trapping quantification, and has potential to improve diagnosis of small airway diseases.Keywords: Air Trapping, Convolutional Neural Network, Deformable Registration, Small Airway Disease, CT, Lung, Semisupervised Learning, Unsupervised Learning Supplemental material is available for this article. © RSNA, 2021 An earlier incorrect version of this article appeared online. This article was corrected on December 22, 2021.

Background: The desaturation–distance ratio (DDR), the ratio of the desaturation area to the distance walked, is a promising, reliable, and simple physiologic tool for functional evaluation in subjects with interstitial lung diseases. Lymphangioleiomyomatosis (LAM) is a rare neoplastic condition frequently associated with exercise impairment. However, DDR has rarely been evaluated in patients with LAM.Objectives: To assess DDR during maximal and submaximal exercises and evaluate whether DDR can be predicted using lung function parameters.Methods: A cross-sectional study was conducted in a cohort of women with LAM. The 6-min walking test (6MWT) and the incremental shuttle walking test (ISWT) were performed, and DDR was obtained from both tests. The functional parameters were assessed at rest using spirometry and body plethysmography. The pulmonary function variables predictive of DDR were also assessed.Results: Forty patients were included in this study. The mean age was 46 ± 10 years. Airway obstruction, reduced DLCO, and air trapping were found in 60, 57, and 15% of patients, respectively. The distance walked and the DDR for the 6MWT and ISWT were, respectively, 517 ± 65 and 443 ± 127 m; and 6.6 (3.8–10.9) and 8.3 (6.2–12.7). FEV1 (airway obstruction) and reduced DLCO and RV/TLC (air trapping) were independent variables predictive of DDR during exercises field tests [DDR6MWT = 18.66–(0.06 × FEV1%pred)–(0.10 × DLCO%pred) + (1.54 × air trapping), Radjust2 = 0.43] and maximal [DDRISWT = 18.84–(0.09 × FEV1%pred)–(0.05 × DLCO%pred) + (3.10 × air trapping), Radjust2 = 0.33].Conclusion: Our results demonstrated that DDR is a useful tool for functional evaluation during maximal and submaximal exercises in patients with LAM, and it can be predicted using airway obstruction, reduced DLCO, and air trapping.

Electrical impedance tomography (EIT) is a medical imaging technique in which low frequency, low amplitude electromagnetic fields applied through electrodes on the skin are used to compute the conductivity and/or permittivity inside the body and form functional images from the reconstructed values. This work describes methods of computing EIT-derived surrogate measures of pulmonary function and identifying regions of air trapping and consolidation from functional EIT images. These methods were developed for pediatric patients with cystic fibrosis, for whom a real-time non-ionizing imaging modality can be of great benefit for monitoring disease progression or a pulmonary exacerbation.

Background and objective This study aims to evaluate clinical and radiological findings and treatment outcomes of the patients with PIBO. Methods One hundred fourteen children were enrolled. Initial demographic and clinical findings were evaluated. Pre- and post-treatment clinical and radiological findings were compared. Results The median age of the patients at initial pulmonary injury was 7,2 months, the median age at diagnosis was 17.5 months. Persistent wheezing was the most common complaint. Thirty-five patients had mechanical ventilation history. 82,5% of patients had clinical improvement. Bronchiectasis, atelectasis, hyperinflation and air trapping in HRCT improved significantly with treatment. Post-treatment Bhalla scores decreased from 8.3 to 6.5 (p= 0,001). Improvement was observed in radiological and clinical findings after treatment. Conclusions This study is one of the largest studies in the literature and one of the few studies that evaluate clinical and radiological outcomes of patients with PIBO.

BackgroundPast exposure to secondhand tobacco smoke (SHS) is associated with exercise limitation. Pulmonary factors including air trapping contribute to this limitation but the contribution of cardiovascular factors is unclear.ObjectiveTo determine contribution of cardiovascular mechanisms to SHS-associated exercise limitation.MethodsWe examined the cardiovascular responses to maximum effort exercise in 245 never-smokers with remote, prolonged occupational exposure to SHS and no known history of cardiovascular disease. We estimated the contribution of oxygen-pulse (proxy for cardiac stroke volume) and changes in systolic (SBP) and diastolic blood pressures (DBP) and heart rate (HR) towards exercise capacity, and examined whether the association of SHS with exercise capacity was mediated through these variables.ResultsAt peak exercise (highest workload completed [WattsPeak]=156±46 watts [135±33 %predicted]), oxygen consumption (VO2Peak) and oxygen-pulse (O2-PulsePeak) were 1,557±476 mL/min (100±24 %predicted) and 11.0±3.0 mL/beat (116±25 %predicted), respectively, with 29% and 3% participants not achieving their predicted normal range. Oxygen saturation at peak exercise was 98±1% and remained >93% in all participants. Sixty-six percent showed hypertensive response to exercise. In models adjusted for covariates, WattsPeak was associated directly with O2-PulsePeak, HRPeak, and SBPPeak and inversely with SHS, air trapping (RV/TLC), and rise of SBP over workload (all PPeak was substantially (41%) mediated through its effect on O2-PulsePeak (PPeak seemed to be mediated through O2-PulsePeak (P=0.078). The likelihood of having baseline respiratory symptoms (modified Medical Research Council score ≥1) was associated with steeper rise in SBP over workload (PConclusionIn a never-smoker population with remote exposure to SHS, abnormal escalation of afterload and an SHS-associated reduction in cardiac output contributed to lower exercise capacity.Key messagesWhat is the key question?What are the cardiovascular health effects of past exposure to secondhand tobacco smoke in never-smokers? How do pulmonary and cardiovascular systems interact in this setting?What is the bottom line?Healthy never-smokers with history of remote past exposure to secondhand tobacco smoke have an abnormal cardiovascular response to exercise, which is characterized by a stroke volume and thus an exercise capacity that are reduced proportional to their years of exposure to secondhand tobacco smoke.Why read on?The abnormal cardiovascular response to exercise in this population reveals the presence of an occult or subclinical pathology that impairs the cardiopulmonary functional reserve and reduces the efficiency of body’s oxygen delivery machinery, which could be disadvantageous during the times of increased cardiopulmonary output demands as in physiological distress or disease.

Objective Hypersensitivity pneumonitis (HP) is an interstitial lung disease caused by the inhalation of specific organic antigens or low-molecular weight substances in genetically susceptible individuals. Although small airway involvement is prominent in patients with chronic HP, conventional pulmonary function tests (PFTs) are relatively insensitive to identify it. Thus, the authors aimed to evaluate resistance (R5) and reactance (X5) values at 5 Hz on inspiration, expiration, and whole breath, as well as small airway resistance (R5–19) values using a forced oscillation technique (FOT) in patients with chronic HP, and their responses after bronchodilator. In addition, R5 and X5 values according to the presence or absence of mosaic attenuation on computed tomography (CT) were compared. Methods PFTs with plethysmography, diffusing capacity of the lungs for carbon monoxide (DLCO) and FOT measurements were performed pre-bronchodilator and post-bronchodilator. High-resolution CT was performed at the same visit, and classified according to the presence or absence of mosaic attenuation. R5 and X5 values were then compared according to the presence or absence of mosaic attenuation on CT. Results Twenty-eight patients with chronic HP (57.1% female; mean age, 56 ± 11.5 years; mean forced vital capacity 57 ± 17% predicted) were evaluated. All patients had low X5 values, reflecting lower lung compliance, and only three (8%) demonstrated elevated R5 (whole-breath) values. No patients exhibited bronchodilator response in R5, X5 and R5–19 values. In patients who exhibited greater extension of mosaic attenuation (n = 11), R5 and X5 values could not discriminate those with a greater presence of these areas on CT. Conclusions The results suggest that FOT does not help to additionally characterise concomitant small airway involvement in patients with chronic fibrotic HP who demonstrate restrictive ventilatory pattern in conventional PFTs. Nevertheless, FOT appeared to better characterise decreased lung compliance due to fibrosis through X5. Bronchodilator therapy did not appear to induce an acute response in chronic HP patients with restrictive disease. The precise role of FOT in subacute HP and obstructive chronic HP, therefore, must be evaluated.

Purpose Combined pulmonary fibrosis and emphysema (CPFE) has emerged as a new syndrome with characteristics of both fibrosis and emphysema. We determined the impacts of radiologic emphysema severity on pulmonary function tests (PFTs), exercise capacity and mortality. Patients and methods IPF patients (n = 110) diagnosed at the Chest Diseases Clinic between September 2013 and January 2016 were enrolled in the study and followed up until June 2017. Visual and digital emphysema scores, PFTs, pulmonary artery pressure (sPAP), 6-minute walking test, composite physiologic index (CPI), and survival status were recorded. Patients with emphysema and those with pure IPF were compared. Results The CPFE-group had a significantly greater ratio of men(p Conclusions The presence and severity of emphysema affects pulmonary function in IPF. Patients with CPFE have reduced diffusion capacity, more severe air trapping, worse muscle weakness, more severe exercise desaturation, and pulmonary hypertension. CPI and pulmonary hypertension are two independent risk factors for mortality in subjects with CPFE.

Introduction: The post-laryngectomy state is characterized by several alterations in lung function. A reliable estimation of lung function can be very useful in laryngectomees to prevent postoperative complications and to evaluate the results of the treatment. Objective: Characterize the presence of respiratory functional disorders and the functional pattern of laryngectomees through the use of an extratracheal device. Methods: This transversal study included 50 patients submitted to total laryngectomy at least 6 months prior to this investigation, as the treatment of choice for laryngeal cancer. Results: 56% percent of the participants had altered breathing pattern, distributed as follows: 14 with obstructive pattern with no air trapping, 11 with obstructive pattern with air trapping and only 3 with restrictive pattern. On average, the diffusion decreased (74.3%) and airway resistance increased (121.7%) when compared to the expected average values for the Brazilian individuals. Conclusion: Most patients submitted to total laryngectomy present altered lung function, usually the obstructive type, frequently associated to a history of smoking. Resumo: Introdução: A condição pós-laringectomia é caracterizada por várias alterações na função pulmonar. Uma estimativa confiável da função pulmonar pode ser muito útil em pacientes laringectomizados para prevenir complicações após as intervenções cirúrgicas e avaliar os resultados do tratamento. Objetivo: Caracterizar a presença de distúrbios funcionais respiratórios e o padrão funcional de pacientes laringectomizados através do uso de um dispositivo extratraqueal. Método: Estudo transversal que incluiu 50 pacientes submetidos à laringectomia total pelo menos seis meses antes desta investigação, como tratamento de escolha para o câncer de laringe. Resultados: Dos participantes, 56% apresentavam padrão respiratório alterado, assim distribuídos: 14 com padrão obstrutivo sem aprisionamento aéreo, 11 com padrão obstrutivo e aprisionamento aéreo e apenas três com padrão restritivo. Em média, verificou-se que a difusão encontrava-se diminuída (74,3%) e a resistência das vias aéreas aumentada (121,7%) em relação aos resultados esperados em brasileiros. Conclusão: A maioria dos pacientes submetidos à laringectomia total apresenta função pulmonar alterada, do tipo obstrutiva, quase sempre associada a história de tabagismo. Keywords: Respiratory function tests, Spirometry, Plethysmography, Laryngectomy, Squamous cell, Palavras-chave: Testes de função respiratória, Espirometria, Pletismografia, Laringectomia, Célula escamosa

Patients with respiratory failure due to obstructive lung disease present a challenge to the emergency physician. These patients have physiologic abnormalities that prevent adequate gas exchange and lung mechanics which render them at increased risk of cardiopulmonary decompensation when managed with invasive mechanical ventilation. This article addresses key principles when managing these challenging patients: patient-ventilator synchrony, air trapping and auto-positive end-expiratory pressure, and airway pressures. This article provides a practical workflow for the emergency physician responsible for managing these patients.

INTRODUCTION Chronic lung disease is common in perinatally HIV-infected children as they increasingly surviving into adolescence. There are few data on the radiologic spectrum of disease in this population. METHODS Contrasted high-resolution computed tomography (HRCT) was performed in ambulatory South African adolescents enrolled in a prospective study of perinatally-infected adolescents aged 9 to 14 years established on combined antiretroviral therapy (cART) and followed for 36 months. Consecutive participants with reduced lung function (defined by a forced expiratory volume in 1 second [FEV1] of

To evaluate the predictive role of computed tomography (CT) on acute rejection in patients who underwent lung transplantation (LT). Seventy-eight patients who underwent LT were evaluated in our study. The CT scans were reviewed by three different radiologists, who evaluated the findings potentially associated with acute rejection such as air trapping, tree-in-bud, consolidations, crazy paving, ground-glass opacity, bronchiectasis, thickening of intralobular or interlobular septa and presence of pleural effusion. The association between a tissue diagnosis of acute rejection and the above-mentioned CT findings was assessed using a multivariate model of logistic regression. Based on our results, none of the CT findings included in the study, alone or in combination, showed significant statistical association with the diagnosis of acute rejection. CT is a very useful technique for the assessment of lung transplant recipients although it has limited accuracy for the assessment of acute rejection. None of the radiological findings considered in our study was significantly associated with histologically proven acute rejection.

Background Chest computed tomography (CT) scans have a recognised role in investigating adults with severe asthma to exclude alternative diagnoses, but its role in children is less clear. The objective of this study was to review the CT findings of our local cohort of children with severe asthma and to explore whether clinical or pathobiological parameters predicted CT changes. Methods Retrospective observational single centre study including all children attending the Leicester difficult asthma clinic (DAC) who underwent a chest CT from 2006 to 2011. Additionally, we recruited eight age-matched, non-asthmatic controls to compare differences in CT findings between asthmatic and non-asthmatic children. All CT images were independently scored by two radiologists. The DAC patients were sub-divided into binary groups for each abnormality identified so that comparisons could be made against recorded clinical variables including age, lung function, serum total IgE levels, and sputum leukocyte differential cell counts. Results Thirty DAC patients (median 12 yrs., range 5–16) were included. The most common abnormalities were bronchial wall thickening (BWT) and air trapping (AT), observed in 80 and 60% of DAC patients. Bronchiectasis (BE) was identified in 27% of DAC patients. DAC patients with evidence of BE on CT images were older than those without BE (13.9 ± 0.67 vs 11.5 ± 0.61, p = 0.038). We also identified a positive correlation between increasing BE severity and extent with age (r = 0.400, p = 0.028). Conclusion Abnormal CT findings were highly prevalent in our cohort of children with severe asthma, with bronchiectasis identified in approximately one third of children. We found no alternative diagnoses that resulted in a change in clinical management.

Endoscopic lung volume reduction (ELVR) therapies are gaining prominence as a treatment option with guideline recommendations by COPD GOLD and NICE and the recent FDA approval for endobronchial valves. The transition from an experiment-based therapy only to clinical care comes with new challenges. A significant volume of evidence-based data has been published; all data demonstrate consistent improvements in several aspects of patient outcomes. Patients suffering from severe air trapping and thoracic hyperinflation seem to benefit the most from ELVR. In addition to lung function, baseline assessment should ideally include cardiopulmonary exercise testing, high-resolution computer tomography scan, perfusion scintigraphy, and echocardiography. This expert ELVR statement updates best practice recommendations from 2017 regarding patient selection and utilization of these various techniques for treating patients with advanced emphysema.

Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable disease, which has caused serious social and economic burden. The main characteristic of COPD is the heterogeneity of disease, manifesting as emphysema, functional small airways disease (fSAD) and large airway diseases. Imaging plays an important role in the evaluation of COPD. In this article, we summarized the recent advances in the imaging of COPD, especially in the quantitative and functional evaluations of the disease. Imaging provides the detailed anatomical, quantitative and function information, illustrates regional heterogeneity and spatial distribution, as well as provides microstructural assessment on the alveolar level. Especially, air trapping index (ATI), parametric response mapping (PRM), gas exchange and texture analysis facilitate the early diagnosis, phenotype classification, severity and therapeutic effect evaluation.

Lung cancer, chronic obstructive pulmonary disease, and cardiovascular disease are highly prevalent in the general population and expected to cause most deaths by 2050. For these "Big-3," treatment might cure, delay, or stop the progression of disease at a very early stage. Lung nodule growth rate (a biomarker for lung cancer), emphysema/air trapping (a biomarker for chronic obstructive pulmonary disease), and coronary artery calcification (a biomarker for cardiovascular disease) are imaging biomarkers of early stages of the Big-3 that can be acquired with low-dose computed tomography (CT). We hypothesize that a (combined) low-dose CT examination for detection of all 3 diseases may significantly improve the cost-effectiveness of screening in the future. We review the current evidence of the imaging biomarkers for the detection of the Big-3 diseases and present the potential health economic potential of Big-3 screening. Furthermore, we review the low-dose CT protocols to acquire these biomarkers and describe the technical considerations when combining the CT protocols for the different biomarkers.

Tidal volume at peak exercise and vital capacity ratio (VTpeak/VC) and VTpeak/inspiratory capacity (IC) were used to differentiate lung expansion in subjects with normal health and chronic obstructive pulmonary disease (COPD) from that in subjects with restrictive ventilation. However, VC and IC variably change due to pseudorestriction of lung volumes. Thus, these variables are currently not recommended. In contrast, total lung capacity (TLC) does little change during exercise. The aims of the study investigated whether VTpeak/TLC is more significantly correlated with static air trapping and lung hyperinflation in patients with COPD than VTpeak/IC, VTpeak/FVC, and VTpeak/SVC (study 1), and developed a marker to replace dynamic IC maneuvers by evaluation of the relationship between end-expiratory lung volume (EELV) and VTpeak/TLC and identification of a cutoff value for VTpeak/TLC (study 2). One hundred adults with COPD (study 1) and 23 with COPD and 19 controls (study 2) were analyzed. Spirometry, lung volume, diffusing capacity, incremental cardiopulmonary exercise tests with dynamic IC maneuvers were compared between groups. An ROC curve was generated to identify a cut off value for VTpeak/TLC. In study 1, VTpeak/TLC was more significantly associated with airflow obstruction, static air trapping and hyperinflation. In study 2, VTpeak/TLC was highly correlated with EELV in the patients (r = −0.83), and VTpeak/TLC ≥ 0.27 predicted that 18% of the patients with static air trapping and hyperinflation can expand their VT equivalent to the controls. In conclusions, VTpeak/TLC was superior to other VTpeak/capacities. VTpeak/TLC may be a marker of dynamic hyperinflation in subjects with COPD, thereby avoiding the need for dynamic IC maneuvers. VTpeak/TLC

Introduction: In severe asthma, management of life-threatening air trapping that persists despite initiation of standard asthma treatment is difficult in the absence of extracorporeal membranous ox...

Introduction Pulmonary interstitial glycogenosis (PIG) is a rare infant interstitial lung disease characterized by an increase in the number of interstitial mesenchymal cells, presenting as enhanced cytoplasmic glycogen, and is considered to represent the expression of an underlying lung development disorder. Methods This study describes the clinical, radiological, and functional characteristics and long-term outcomes (median 12 years) of nine infants diagnosed with isolated PIG associated with alveolar simplification in the absence of other diseases. Results All patients presented with tachypnea. Additionally, seven patients had breathing difficulties and hypoxemia. Abnormalities in chest-computerized tomography (CT) with a pattern of ground-glass opacity, septal thickening, and air trapping were observed in all individuals, with images suggesting abnormal alveolar growth (parenchymal bands and architectural distortion). All lung biopsies showed alveolar simplification associated with an increased number of interstitial cells, which appeared as accumulated cytoplasmic glycogen. In the follow-up, all patients were asymptomatic. The respiratory function test was normal in only two patients. Five children showed an obstructive pattern, and two children showed a restrictive pattern. Chest-CT, performed after an average of 6.5 years since the initial investigation, revealed a partial improvement of the ground-glass opacity pattern; however, relevant alterations persisted. Conclusion Although the patients with PIG in the absence of other associated pathologies had a good clinical outcome, significant radiographic alterations and sequelae in lung function were still observed after a median follow-up of 12 years, suggesting that PIG is a marker of some other persistent abnormalities in lung growth, which have effects beyond the symptomatic period.

Objective To describe the clinical characteristics and outcomes of patients diagnosed with obliterative bronchiolitis (OB) not associated with transplantation or point-source exposures to inhaled toxins. Patients and Methods We compiled all confirmed diagnoses of OB at our institution and analyzed their demographic characteristics, treatments, and outcomes as defined by pulmonary function tests (PFTs) and transplant-free mortality. The study period ranged from July 2007 to August 2017. Histological diagnosis was confirmed by a pathologist, and high-resolution chest computed tomography (CT) scans were reviewed and scored by chest radiologists. We also performed a systematic literature review of sporadic OB series. Results We identified 19 confirmed cases at our institution and 9 publications in the literature containing 104 patients. In both our series and the literature, patients were disproportionately middle-aged Caucasian women. The disease was idiopathic in 42% and was associated with connective tissue diseases and inhalational exposures in 31% and 15%, respectively. Chest CT showed expiratory air trapping in all patients. Patients were treated with corticosteroids, steroid-sparing agents, and macrolides in 77%, 46%, and 22%, respectively. Over a median follow-up in our series of 1703 days (range, 11-3206 days), PFTs did not change significantly. In all series combined, mortality incidence from any cause was 82/1000 patient-years (95% CI, 65-102). Of 14 patients who died, 3 deaths were due to respiratory failure and 5 were potentially related to complications of immunosuppressive therapy. Conclusion Sporadic OB is a rare disease that is uniformly associated with air trapping on high-resolution chest CT. The diagnosis should be established with surgical biopsy if possible. The illness is not typically progressive.

Objective To evaluate the utility of radiodensity ratio between lungs on chest X-ray for the diagnosis of radiolucent foreign body aspiration (FBA) in children. Methods X-rays of 33 patients with confirmed diagnosis of FBA by bronchoscopy were compared to 66 control patients. We divided the study group into three subgroups: symmetric (13-patients), right-oblique (RO;12-patients) and left-oblique (LO;8-patients). Results When we compared FBA-symmetric-subgroup to symmetric-control-group, FBA-RO-subgroup to RO-control-group and FBA-LO-subgroup to LO-control-group, radiodensity ratios were significantly higher in the FBA subgroups. Conclusion The calculated radiodensity ratio between lungs on X-ray would be a useful and practical tool for the diagnosis of radiolucent FBA in children.

Objective: The aim of our study was to determine the tomographic findings and prevalence of bronchiectasis in our population of patients with severe asthma, and to identify factors associated with the presence of bronchiectasis in these patients. Materials and methods: We retrospectively collected data from the medical histories of patients referred to the asthma unit of our hospital, with a diagnosis of severe asthma between 2015 and 2017. Patients with ABPA, cystic fibrosis, immunodeficiency or systemic disease were excluded. High-resolution thorax-computed tomodensitography (HRCT) was performed in all patients. A standardized protocol was applied in data collection. Results: A total of 108 patients comprising 50 men (46%) and 58 women (54%) were included in the study. Of the 108 patients, 59 (55%) had at least one abnormality detected by HRCT, the most commonly reported abnormalities being bronchiectasis (35%), bronchial wall thickening (33%), emphysema (7%), atelectasis area (6%), mosaic attenuation due to air trapping (4%), and "tree in bud" image (2%). Subjects with bronchiectasis were older (p = 0.001), had a longer asthma history (p = 0.048), had poorer pulmonary function tests with lower FVC (p = 0.031), had more severe bronchial obstruction with lower FEV1 (p = 0.008) and had lower FEV1/FVC (p = 0.003). They also experienced more frequent hospitalizations in the previous year (p = 0.019) and received treatment with omalizumab more frequently (p = 0.049). Plasma eosinophil count and IgE levels were comparable in both groups. In the multivariate analysis, the presence of bronchiectasis was associated with ages older than 40 (OR: 8.3; 95% CI: 1.7-41.2) and chronic airflow obstruction (OR: 5.4; 95% CI: 1.9-15.3). Conclusions: We found that in patients with severe asthma, the prevalence of bronchiectasis is high and that bronchiectasis is associated with a longer asthma history, greater severity and, more importantly, chronic airflow obstruction. These findings are still insufficient evidence to considere features of asthma-bronchiectasis overlap syndrome, a distinct phenotype of severe asthma, but bronchiectasis is a frequent phenomenon leading to a more severe disease with frequent exacerbations. The performance of thorax HRCT on patients with severe asthma can help to evaluate management strategies for the disease in order to improve treatment and prognosis.

Background In children with cystic fibrosis (CF) lung clearance index (LCI) from multiple-breath washout (MBW) correlates with structural lung disease. As a shorter test, single-breath washout (SBW) represents an attractive alternative to assess the ventilation distribution, however, data for the correlation with lung imaging are lacking. Methods We assessed correlations between phase III slope (SIII) of double-tracer gas SBW, nitrogen MBW indices (LCI and moment ratios for overall ventilation distribution, Scond, and Sacin for conductive and mainly acinar ventilation, respectively) and structural lung disease assessed by chest computed tomography (CT) in children with CF. Results In a prospective cross-sectional study data from MBW, SBW, and chest CT were obtained in 32 children with CF with a median (range) age of 8.2 (5.2-16.3) years. Bronchiectasis was present in 24 (75%) children and air trapping was present in 29 (91%). Median (IQR) SIII of SBW was -138.4 (150.6) mg/mol. We found no association between SIII with either the MBW outcomes or CT scores (n = 23, association with bronchiectasis extent r = 0.10, P = 0.64). LCI and Scond were associated with bronchiectasis extent (n = 23, r = 0.57, P = 0.004; r = 0.60, P = 0.003, respectively). Conclusions Acinar ventilation inhomogeneity measured by SBW was not associated with structural lung disease on CT. Double-tracer SBW added no benefit to indices measured by MBW.

Patient: Female, 41 Final Diagnosis: Bronchiolitis obliterans after SJS Symptoms: Dyspnea Medication: — Clinical Procedure: — Specialty: Pulmonology Objective: Rare disease Background: Bronchiolitis obliterans is the term used to describe a clinical syndrome of irreversible airflow obstruction. Among the etiologies linked to this entity is the rarely reported association with Stevens-Johnson syndrome, which has had a poor outcome in most of the previously published cases. The optimum management of bronchiolitis obliterans as a complication of Stevens-Johnson syndrome is not well defined. Case Report: A 41-year-old woman developed significant shortness of breath 3 months after recovering from Stevens-Johnson syndrome precipitated by a second-generation cephalosporin. She was found to have severe irreversible airway obstruction on physiology studies, and computed tomography scans of the inspiratory and expiratory phases of respiration showed air trapping that was more prominent on expiratory films. The patient was diagnosed with bronchiolitis obliterans, for which bronchodilators and long-term macrolide therapy were administered. Although she did not recover completely, her follow-up physiology studies showed that the bronchiolitis obliterans was stable. Conclusions: Bronchiolitis obliterans secondary to Stevens-Johnson syndrome is a rare entity that is progressive and can lead to functional impairment. Identifying the disease at an early stage might stabilize or slow its progression. Herein, we describe a case of bronchiolitis obliterans as a complication of Stevens-Johnson syndrome and review the literature to raise awareness of this condition, highlight its course, and discuss the available treatments.

Background Severe hyperinflation causes detrimental effects such as dyspnea and reduced exercise capacity and is an independent predictor of mortality in COPD patients. Static lung volumes are required to diagnose severe hyperinflation, which are not always accessible in primary care. Several studies have shown that the area under the forced expiratory flow-volume loop (AreaFE) is highly sensitive to bronchodilator response and is correlated with residual volume/total lung capacity (RV/TLC), a common index of air trapping. In this study, we investigate the role of AreaFE% (AreaFE expressed as a percentage of reference value) and conventional spirometry parameters in indicating severe hyperinflation. Materials and methods We used a cohort of 215 individuals with COPD. The presence of severe hyperinflation was defined as elevated air trapping (RV/TLC >60%) or reduced inspiratory fraction (inspiratory capacity [IC]/TLC 60% and IC/TLC

BACKGROUND Structural lung changes seen on computed tomography (CT) scans in Cystic Fibrosis (CF) and Primary Ciliary Dyskinesia (PCD) are currently described using scoring systems derived from CF populations. This practise assumes lung damage in the two conditions is identical, potentially resulting in a failure to identify PCD-specific changes. Our study addresses this assumption. METHODS A total of 58 CT scans from 41 PCD patients (age 2-48 years) were examined and the presence and extent of abnormalities common in CF; bronchiectasis, bronchial wall thickening, atelectasis, mucous plugging, and air trapping noted. Further assessment of the PCD scans by an experienced chest radiologist identified several unique PCD specific changes. RESULTS Bronchial wall thickening was the commonest abnormality seen in PCD. All abnormalities were present more often in middle and lower lobes than in upper lobes (P

Asthma is a heterogeneous disease with diverse clinical phenotypes that have been identified via cluster analyses. However, the classification of phenotypes based on quantitative CT (qCT) is poorly understood. The study was conducted to investigate CT determination of uncontrolled asthma phenotypes. Sixty-five patients with uncontrolled asthma (37 with severe asthma, 28 with non-severe asthma) underwent detailed clinical, laboratory, and pulmonary function tests, as well as qCT analysis. Twenty-five healthy subjects were also included in this study and underwent clinical physical examinations, pulmonary function tests, and low-dose CT scans. The mean lumen area/body surface area ratio was smaller in patients with severe uncontrolled asthma compared with that in healthy subjects (9.84 mm2 [SD, 2.57 mm2], 11.96 mm2 [SD, 3.09 mm2]; p = 0.026). However, the percentage of mean wall area (WA) was greater (64.39% [SD, 2.55%], 62.09% [SD, 3.81%], p = 0.011). Air trapping (measured based on mean lung density and VI−856 [%] on expiratory scan) was greater in patients with severe uncontrolled asthma than in those with non-severe uncontrolled asthma and was higher in all patients with uncontrolled asthma than that in healthy subjects (all p

Pulmonary emphysema is part of pathological condition in chronic obstructive pulmonary disease (COPD) which is characterized by lung parenchymal destruction. Morphology classification of emphysema had been made according to histologic structure in pathology. There were some causes known to be the culprit of emphysema; one that caught most attention is protease-antiprotease activity from cigarette smoke exposure. Destructive effect of emphysema gives disturbance of lung function in expiration (obstruction). The primary mechanism is elastic recoil reduction which causes air trapping, lung volume increase, lung compliance increase and airways that is susceptible to collapse. Hyperinflation in emphysema causes some disadvantages which complicate inspiration and give a dyspnea sensation. Equal pressure point drop in emphysema happens because of elastic recoil reduction. This drop may cause early airway closure. (J Respir Indo 2019; 39(1): 60-9)

It is estimated that approximately 3.5 million American adults have been diagnosed with emphysema, an irreversible destruction of the alveolar lung parenchyma. In advanced cases, the lung damage is so severe that significant air trapping occurs and does not improve with the use of bronchodilators and other conventional medicines used for chronic obstructive pulmonary disease (COPD). Viable surgical options include bullectomy, lung volume reduction surgery (LVRS), and lung transplantation but many patients may not be appropriate candidates for these procedures and/or there are long wait times for transplantation. Recently, the U.S. Food and Drug Administration (FDA) approved the Zephyr® endobronchial valve (EBV) (Zephyr Valve EBV; Pulmonx Corporation, Redwood City, California) for bronchoscopic lung volume reduction for patients with severe emphysema who are not responsive to medical therapy. This 1-way valve, the size of a pencil eraser, is inserted into the targeted diseased portion of the lung. Typically, 4 to 8 valves are inserted into the chosen emphysematous lobe and will allow air to escape out of that region but prevent any further air from entering, leading to deflation, and ultimately, total lobar collapse over a matter of weeks. An earlier study with the Zephyr® valves, the “Endobronchial Valve for Emphysema Palliation Trial, (VENT)” study,1 was a multicenter trial with 321 participants (220 with EBV insertion) that demonstrated statistically significant improvements in forced expiratory volume in 1 second (FEV1) and the 6-minute walk distance test (6MWD) between EBV and standard of care (SoC) groups but these were not clinically meaningful differences (mean change in FEV1 was 60 mL and median difference from baseline 6MWD 19.1 m).1 Post hoc analysis indicated that the best responders were those who demonstrated the following criteria: little to virtually no collateral ventilation to ipsilateral adjacent lobes, complete lobar occlusion achieved with the correct occlusive positioning of the valves in all segmental and sub-segmental airways and complete intact fissures between lobes.2,3 With this information, Pulmonx developed a unique technology-- Chartis (Pulmonx Corporation, Redwood City, California) a device that tests for collateral ventilation to judge the appropriateness of valve insertion.4 The Chartis system consists of a console connected to a balloon catheter with a central channel that is used to occlude the target lobe and to subsequently measure pressure and flow to calculate resistance to airflow and hence to quantify collateral ventilation in that lobe.4 More recently, advanced computed tomography (CT) scan analysis techniques have been developed that can virtually eliminate the need for testing with the Chartis system.5,6 Advanced CT analysis techniques have become a key element of deciding on the appropriateness of candidates. This has been confirmed with several short-term single center studies.2,7,8 The FDA actually granted the Zephyr® valve “breakthrough device” designation, allowing the FDA to provide guidance on efficient device development and to expedite evidence generation and review of the device. This designation generally signals the recognition that there are relatively few viable options for treating the targeted patient population. Indeed, the first study we review by Criner and colleagues, LIBERATE (below) is the first large, prospective, randomized controlled, multicenter study to evaluate the effectiveness, safety and durability of the benefit out to 12 months in patients with severe heterogeneous emphysema and with little to no collateral ventilation in the target lung. In order to expedite approval, the FDA required that, compared to previous studies, the primary endpoints show a greater magnitude of difference between Zephyr valve insertion and SoC versus a sham procedure and then SoC. In this Journal Club we will review this pivotal study that led to the approval of the Zephyr® valve in the United States and other recent studies that have evaluated the efficacy and safety of this device. Note: Abstracts are presented in their original, published format and have not been edited to match JCOPDF style.

BackgroundThe impact of Aspergillus on lung disease in young children with cystic fibrosis is uncertain.AimsTo determine if positive respiratory cultures of Aspergillus species are associated with: (1) increased structural lung injury at age 5 years; (2) accelerated lung function decline between ages 5 years and 14 years and (3) to identify explanatory variables.MethodsA cross-sectional analysis of association between Aspergillus positive bronchoalveolar lavage (BAL) cultures and chest high-resolution CT (HRCT) scan findings at age 5 years in subjects from the Australasian Cystic Fibrosis Bronchoalveolar Lavage (ACFBAL) study was performed. A non-linear mixed-effects disease progression model was developed using FEV1% predicted measurements at age 5 years from the ACFBAL study and at ages 6–14 years for these subjects from the Australian Cystic Fibrosis Data Registry.ResultsPositive Aspergillus BAL cultures at age 5 years were significantly associated with increased HRCT scores for air trapping (OR 5.53, 95% CI 2.35 to 10.82). However, positive Aspergillus cultures were not associated with either FEV1% predicted at age 5 years or FEV1% predicted by age following adjustment for body mass index z-score and hospitalisation secondary to pulmonary exacerbations. Lung function demonstrated a non-linear decline in this population.ConclusionIn children with cystic fibrosis, positive Aspergillus BAL cultures at age 5 years were associated contemporaneously with air trapping but not bronchiectasis. However, no association was observed between positive Aspergillus BAL cultures on FEV1% predicted at age 5 years or with lung function decline between ages 5 years and 14 years.

A 47-year-old patient presented to the emergency room with an attack of acute severe asthma. In spite of all primary measures, the patient was deteriorating. Arterial blood gases showed hypercarbia and acidemia. The patient was shifted to the intensive care unit connected to noninvasive ventilation for 3 h, without any obvious improvement. Decision was taken to intubate, ventilate, and keep her deeply sedated. On the 4th day of ventilation, the patient developed sudden tension pneumothorax and she was near to arrest. Management for tension pneumothorax was immediate and successful. After that, chest X-ray and computerized tomography scan showed hemopneumothorax, for which a chest tube was inserted in both chest sides and blood transfusion was initiated immediately. After this incidence, the patient's parameters improved dramatically. Four days later, the patient was extubated and kept in intensive care unit till the chest tubes were removed and then shifted to the ward and discharged on day 15 from admission.

Early stages of chronic obstructive pulmonary disease (COPD) are characterized by the loss and narrowing of terminal bronchioles in the lung, resulting in “air-trapping,” often occurring before overt emphysema manifests. Individuals with an airway-predominant phenotype of COPD display extensive lung air-trapping and are at greater cardiovascular disease (CVD) risk than COPD patients with an emphysema-predominant phenotype. We hypothesized that the degree of computed tomography (CT)-quantified lung air-trapping would be associated with greater aortic and carotid artery stiffness and lower endothelial function, known biomarkers of CVD risk. Lung air-trapping was associated with greater aortic stiffness (carotid femoral pulse wave velocity, CFPWV) ( r = 0.60, P = 0.007) and carotid β-stiffness ( r = 0.75, P = 0.0001) among adults with ( n = 10) and without ( n = 9) a clinical diagnosis of COPD and remained significant after adjusting for blood pressure (BP) and smoking history (pack-years) (carotid β-stiffness: r = 0.68, P < 0.01; CFPWV r = 0.53, P = 0.03). The association between lung air-trapping and carotid β-stiffness remained significant after additionally adjusting for age and forced expiratory volume 1(FEV1) ( r = 0.64, P = 0.01). In the COPD group only ( n = 10), lung air-trapping remained associated with carotid β-stiffness ( r = 0.82, P = 0.05) after adjustment for age, pack-years, and FEV1. In contrast, no association was observed between CFPWV and lung air-trapping after adjustment for BP, pack-years, age, and FEV1 ( r = 0.12, P = 0.83). Lung air-trapping was not associated with endothelial function (brachial artery flow-mediated dilation) in the entire cohort ( P = 0.80) or in patients with COPD only ( P = 0.71). These data suggest that carotid artery stiffness may be a mechanism explaining the link between airway-predominant phenotypes of COPD and high CVD risk. NEW & NOTEWORTHY Previous cross-sectional studies have demonstrated greater large elastic artery stiffness and lower endothelium-dependent dilation in chronic obstructive pulmonary disease (COPD) patients compared with controls. Furthermore, COPD patients with emphysema have greater aortic stiffness than non-COPD controls, and the degree of stiffness is associated with emphysema severity. The present study is the first to demonstrate that even before overt emphysema manifests, lung air-trapping is associated with carotid artery stiffness in COPD patients independent of blood pressure, age, or smoking history.

Primary spontaneous pneumothorax (PSP) in pediatric patients is less common than in adults. Tall, thin adolescent males are most commonly affected. While clinical guidelines exist for the adult pop...

In pediatric thoracic CT, respiratory motion is generally treated as a motion artifact degrading the image quality. Conversely, respiratory motion in the thorax can be used to answer important clinical questions, that cannot be assessed adequately via conventional static thoracic CT, by utilizing four-dimensional (4D) CT. However, clinical experiences of 4D thoracic CT are quite limited. In order to use 4D thoracic CT properly, imagers should understand imaging techniques, radiation dose optimization methods, and normal as well as typical abnormal imaging appearances. In this article, the imaging techniques of pediatric thoracic 4D CT are reviewed with an emphasis on radiation dose. In addition, several clinical applications of pediatric 4D thoracic CT are addressed in various thoracic functional abnormalities, including upper airway obstruction, tracheobronchomalacia, pulmonary air trapping, abnormal diaphragmatic motion, and tumor invasion. One may further explore the clinical usefulness of 4D thoracic CT in free-breathing children, which can enrich one's clinical practice.

Purpose Computed tomography (CT) findings of bronchiolitis obliterans syndrome (BOS) can be nonspecific and variable. This study aims to measure the incremental value of automated quantitative lung CT analysis to clinical CT interpretation. A head-to-head comparison of quantitative CT lung density analysis by parametric response mapping (PRM) with qualitative radiologist performance in BOS diagnosis was performed. Materials and methods Inspiratory and end-expiratory CTs of 65 patients referred to a post-bone marrow transplant lung graft-versus-host-disease clinic were reviewed by 3 thoracic radiologists for the presence of mosaic attenuation, centrilobular opacities, airways dilation, and bronchial wall thickening. Radiologists' majority consensus diagnosis of BOS was compared with automated PRM air trapping quantification and to the gold-standard diagnosis of BOS as per National Institutes of Health (NIH) consensus criteria. Results Using a previously established threshold of 28% air trapping on PRM, the diagnostic performance for BOS was as follows: sensitivity 56% and specificity 94% (area under the receiver operator curve [AUC]=0.75). Radiologist review of inspiratory CT images alone resulted in a sensitivity of 80% and a specificity of 69% (AUC=0.74). When radiologists assessed both inspiratory and end-expiratory CT images in combination, the sensitivity was 92% and the specificity was 59% (AUC=0.75). The highest performance was observed when the quantitative PRM report was reviewed alongside inspiratory and end-expiratory CT images, with a sensitivity of 92% and a specificity of 73% (AUC=0.83). Conclusions In the CT diagnosis of BOS, qualitative expert radiologist interpretation was noninferior to quantitative PRM. The highest level of diagnostic performance was achieved by the combination of quantitative PRM measurements with qualitative image feature assessments.

Background Actigraphy can provide useful patient-centered outcomes for quantification of physical activity in the “real-world” setting. Methods To characterize the relationship of actigraphy outputs with “in-laboratory” measures of cardiopulmonary function and respiratory symptoms in pre-COPD, we obtained actigraphy data for 8 h/day for 5 consecutive days a week before in-laboratory administration of respiratory questionnaires, PFT, and CPET to a subgroup of subjects participating in the larger study of the health effects of exposure to secondhand tobacco smoke who had air trapping but no spirometric obstruction (pre-COPD). Using machine learning approaches, we identified the most relevant actigraphy predictors and examined their associations with symptoms, lung function, and exercise outcomes. Results Sixty-one subjects (age = 66±7 years; BMI = 24±3 kg/m2; FEV1/FVC = 0.75 ± 0.05; FEV1 = 103 ± 17 %predicted) completed the nested study. In the hierarchical cluster analysis, the activity, distance, and energy domains of actigraphy, including moderate to vigorous physical activity, were closely correlated with each other, but were only loosely associated with spirometric and peak exercise measures of oxygen consumption, ventilation, oxygen-pulse, and anaerobic threshold (VO2AT), and were divergent from symptom measures. Conversely, the sedentary domain clustered with respiratory symptoms, air trapping, airflow indices, and ventilatory efficiency. In Regression modeling, sedentary domain was inversely associated with baseline lung volumes and tidal breathing at peak exercise, while the activity domains were associated with VO2AT. Respiratory symptoms and PFT data were not associated with actigraphy outcomes. Discussion Outpatient actigraphy can provide information for “real-world” patient-centered outcomes that are not captured by standardized respiratory questionnaires, lung function, or exercise testing. Actigraphy activity and sedentary domains inform of distinct outcomes.

Background Reversibility measured by spirometry in chronic obstructive pulmonary disease (COPD) is defined as an increase in forced expiratory volume in first second (FEV1) that is both more than 12% and 200 mL above the pre-bronchodilator value in response to inhaled bronchodilators. FEV1 only may not fully reverberate the changes caused by reduction in air trapping or hyperinflation. To date, the studies that examined the effect of inhaled bronchodilators (BD) on residual volume (RV) and total lung capacity (TLC) are limited. This study was carried out to assess the differences between flow and volume responses after bronchodilator reversibility testing in patients with different COPD GOLD stages (GOLD stage I to stage IV). Spirometry and whole body plethysmography were done before and 15 min after inhalation of 400 μg salbutamol. Results Majority (53.3%) of cases were volume responders, 18.7% were flow responders, 20% were flow and volume responders, and 8% were non responders. Significant increase in Δ FEV1% was found in 15% of cases while 55% showed a significant increase in Δ FVC (P= < 0.001). Mean difference of Δ FVC (L) post BD was significantly increased with advancing GOLD stage (P= 0.03). A cutoff point > 20% for Δ RV% had 70% sensitivity and 60% specificity and > 12% for Δ TLC% showed 90% sensitivity and 45% specificity for prediction of clinically significant response to BD based on FEV1. A cutoff point > 18% for Δ RV% had 78% sensitivity and 29% specificity and > 14% for Δ TLC% had 50% sensitivity and 70% specificity for prediction of clinically significant response to BD based on FVC. Conclusion ΔFEV1 underestimates the true effect of bronchodilators with advancing GOLD stage. Measurement of lung volumes in addition to the standard spirometric indices is recommended when determining bronchodilator response in COPD patients.

Background Primary graft dysfunction (PGD) is an important contributor to early mortality in lung transplant recipients and is associated with impaired lung function. The radiographic sequelae of PGD on computed tomography (CT) have not been characterized. Methods We studied adult double lung transplant recipients from 2010-2016 for whom protocol 3-month post-transplant CT scans were available. We assessed CTs for changes including pleural effusions, ground glass opacification, atelectasis, centrilobular nodularity, consolidation, interlobular septal thickening, air trapping and fibrosis, and their relationship to prior post-transplant PGD, future lung function, post-transplant baseline lung allograft dysfunction (BLAD) and chronic lung allograft dysfunction (CLAD). Results Of 237 patients studied, 50 (21%) developed grade 3 PGD (PGD3) at 48 or 72h. PGD3 was associated with increased interlobular septal thickening (p=0.0389) and atelectasis (p=0.0001) at 3 months, but only atelectasis remained associated after correction for multiple testing. Atelectasis severity was associated with lower peak forced expiratory volume in 1 second (FEV1) and increased risk of BLAD (p=0.0014) but not with future CLAD onset (p=0.7789). Conclusions Severe PGD was associated with atelectasis on 3-month post-transplant CT in our cohort. Atelectasis on routine CT may be an intermediary identifiable stage between PGD and future poor lung function.

AIM To evaluate the cardiovascular, tracheobronchial and pulmonary abnormalities associated with tetralogy of Fallot with absent pulmonary valve syndrome (TOF-APVS) on multidetector computed tomograpgy (MDCT) angiography. MATERIALS AND METHODS We conducted a retrospective review of our electronic database from January, 2014 to December, 2020 to identify pediatric patients diagnosed with TOF-APVS on MDCT angiography. Pulmonary anatomy, associated tracheobronchial and coronary compression, compression of intrapulmonary bronchi, lung parenchymal changes and other associated cardiovascular abnormalities were evaluated. RESULTS Forty-seven patients with TOF-APVS were included in the study. Compression of the airways was observed at multiple levels; 4 (8.5%) patients had carinal compression while right main bronchus and left main bronchus compression was seen in 12 (25.5%) and 16 (34.0%) patients, respectively. Forty-three (91.5%) patients showed abnormal pulmonary arterial branching at the segmental level and compression at the level of intrapulmonary bronchi was seen in 24 (51.1%) patients. Some degree of air trapping was seen in 35 (74.5%) patients whereas atelectasis was observed in 15 (31.9%) patients. Mild coronary arterial compression was seen in 3 (6.4%) patients. CONCLUSION TOF-APVS is characterized by aneurysmal dilatation of pulmonary arteries leading to a varying degree of airway compression. However, even in the absence of compression of the trachea and main bronchi, there can be distal bronchial compression secondary to abnormal pulmonary arterial branching resulting in lung abnormalities in the majority of these patients. This study highlights the importance of dedicated airway assessment in addition to cardiovascular morphological assessment by MDCT angiography, before planning surgery.

Background Acute severe asthma is a life-threatening medical emergency. Characteristics of asthma include increased airway resistance and dynamic pulmonary hyperinflation that can manifest in dangerous levels of hypercapnia and acidosis, with significant mortality and morbidity. Severe respiratory distress can lead to endotracheal intubation followed by mechanical ventilation, which can cause increased air trapping with dynamic hyperinflation, predisposing the lungs to barotraumas. Case presentation The present case report describes the use of the minimally invasive ECCO2R ProLUNG® (Estor) with protective low-tidal-volume ventilation, in a Caucasian patient with near-fatal asthma and with no response to conventional therapy. Conclusions Since hypercarbia rather than hypoxemia is the primary abnormality in status asthmaticus, a rescue therapeutic strategy combining the ECCO2R membrane ProLUNG® (Estor) with ultra-protective low-tidal-volume ventilation can be successfully applied to limit the risk of severe barotrauma during invasive mechanical ventilation. ECCO2R ProLUNG® is a partial respiratory support technique that, based on the use of an extracorporeal circuit with a gas-exchange membrane, achieves relevant CO2 clearance directly from the blood using double-lumen venous-venous vascular access, at blood flow in the range of 0.4–1.0 L/minute.

Background Adding a slow vital capacity (SVC) to multiple breath washout (MBW) allows quantification of otherwise overlooked signal from under/un-ventilated lung units (UVLU) and may provide a more comprehensive assessment of airway disease than conventional lung clearance index (LCI2.5). Methods We conducted a pilot study on people undergoing MBW tests: 10 healthy controls (HC) and 43 cystic fibrosis (CF) subjects performed an SVC after the standard end of test. We term the new outcome LCI with Short extension (LCIShX). We assessed (i) CF/ HC differences, (ii) variability (iii) effect of pulmonary exacerbation (PEx)/treatment and (iv) relationship with CF computed tomography (CFCT) scores. Results HC/ CF group differences were larger with LCIShX than LCI2.5 (P Conclusions UVLU captured within the LCIShX varies between individuals; the lack of relationship with LCI2.5 demonstrates that new, additional information is being captured. LCIShX repeatability during clinical stability combined with its larger signal around episodes of PEx may lend it superior sensitivity as an outcome measure. Further studies will build on this pilot data to fully establish its utility in monitoring disease status.

Background During the current second wave of COVID-19, the radiologists are expected to face great challenges in differentiation between COVID-19 and other virulent influenza viruses, mainly H1N1. Accordingly, this study was performed in order to find any differentiating CT criteria that would help during the expected clinical overlap during the current Influenza season. Results This study was retrospectively conducted during the period from June till November 2020, on acute symptomatic 130 patients with no history of previous pulmonary diseases; 65 patients had positive PCR for COVID-19 including 50 mild patients and 15 critical or severe patients; meanwhile, the other 65 patients had positive PCR for H1N1 including 50 mild patients and 15 critical or severe patients. They included 74 males and 56 females (56.9%:43.1%). Their age ranged 14–90 years (mean age 38.9 ± 20.3 SD). HRCT findings were analyzed by four expert consultant radiologists in consensus. All patients with COVID-19 showed parenchymal or alveolar HRCT findings; only one of them had associated airway involvement. Among the 65 patients with H1N1; 56 patients (86.2%) had parenchymal or alveolar HRCT findings while six patients (9.2%) presented only by HRCT signs of airway involvement and three patients (4.6%) had mixed parenchymal and airway involvement. Regarding HRCT findings of airway involvement (namely tree in bud nodules, air trapping, bronchial wall thickening, traction bronchiectasis, and mucous plugging), all showed significant p value (ranging from 0.008 to 0.04). On the other hand, HRCT findings of parenchymal or alveolar involvement (mainly ground glass opacities) showed no significant relation. Conclusion HRCT can help in differentiation between non-severe COVID-19 and H1N1 based on signs of airway involvement.