Fluoroscopically measured bronchial collapse in healthy dogs during cough exceeds 25%, and a cutoff of 60% bronchial collapse can be used to distinguish healthy from chronically coughing dogs.

Bronchomalacia, the weakening of bronchial cartilage, is a common cause of cough in dogs. The gold standard for diagnosis of bronchomalacia is bronchoscopy; however, fluoroscopy is often used as a preliminary diagnostic test due to its noninvasiveness. The normal amount of bronchial collapse in healthy dogs using fluoroscopy has not been previously established, with some authors citing <25%. The aims of this prospective and retrospective analytical observational study were to determine the normal amount of airway collapse in healthy animals, the amount of airway collapse in dogs with chronic cough and presumed bronchomalacia, and cut-off values of airway collapse during expiration and cough to distinguish between the two groups. Thoracic fluoroscopy was performed in right and left lateral recumbency during inspiration, expiration, and cough to evaluate the percentage collapse of the trachea and lobar bronchi in 45 healthy and 76 chronically coughing dogs. The bronchi of chronically coughing dogs exhibited a significantly greater amount of collapse during both expiration and cough compared with healthy dogs. Chronically coughing dogs exhibited up to 31.7 ± 26.6% collapse in expiration and 87.5 ± 23.7% collapse during cough, whereas healthy dogs exhibited 14.9 ± 6.1% collapse in expiration and 35.0 ± 13.7% collapse during cough. Based on ROC curves, the authors suggest using cut-off values of 30% during expiration and 60% during cough to distinguish between healthy dogs and those with presumed bronchomalacia. Findings suggest that though healthy dogs can exhibit a greater degree of airway collapse than previously thought, fluoroscopy can be used to distinguish between healthy and presumed bronchomalacic dogs.

ERS statement on tracheomalacia and bronchomalacia in children.

Tracheomalacia and tracheobronchomalacia may be primary abnormalities of the large airways or associated with a wide variety of congenital and acquired conditions. The evidence on diagnosis, classification and management is scant. There is no universally accepted classification of severity. Clinical presentation includes early-onset stridor or fixed wheeze, recurrent infections, brassy cough and even near-death attacks, depending on the site and severity of the lesion. Diagnosis is usually made by flexible bronchoscopy in a free-breathing child but may also be shown by other dynamic imaging techniques such as low-contrast volume bronchography, computed tomography or magnetic resonance imaging. Lung function testing can provide supportive evidence but is not diagnostic. Management may be medical or surgical, depending on the nature and severity of the lesions, but the evidence base for any therapy is limited. While medical options that include bronchodilators, anti-muscarinic agents, mucolytics and antibiotics (as well as treatment of comorbidities and associated conditions) are used, there is currently little evidence for benefit. Chest physiotherapy is commonly prescribed, but the evidence base is poor. When symptoms are severe, surgical options include aortopexy or posterior tracheopexy, tracheal resection of short affected segments, internal stents and external airway splinting. If respiratory support is needed, continuous positive airway pressure is the most commonly used modality either via a face mask or tracheostomy. Parents of children with tracheobronchomalacia report diagnostic delays and anxieties about how to manage their child's condition, and want more information. There is a need for more research to establish an evidence base for malacia. This European Respiratory Society statement provides a review of the current literature to inform future study.

Computed tomographic bronchial collapsibility values over 50% may be detected in healthy dogs.

Bronchomalacia and bronchial collapse are important causes of chronic coughing in dogs. The current reference standard diagnostic tests for these problems are flexible bronchoscopy and biopsy. Previous human studies have also supported inspiration/expiration computed tomography (CT) as a diagnostic test. The current prospective, pilot study aimed to determine whether inspiration/expiration CT is also a feasible test for quantifying bronchial collapsibility in dogs. Thoracic CT images were acquired using a 64-row multidetector CT for 10 healthy Beagle dogs during maximal inspiration and expiration. For each scan, one observer measured transverse sectional areas of the mainstem and lobar bronchi, and the dorsal and ventral segmental bronchi of the left cranial lobar bronchus. Diameters for each bronchus were also measured in transverse, sagittal, and dorsal planes. Bronchial collapsibility (%) was calculated as the difference between inspiration/expiration transverse sectional areas divided by the inspiration transverse sectional areas. Mean bronchial collapsibility of all bronchi was 38.20 ± 15.17%. A collapsibility of over 50% was found in the dorsal (n = 7) and ventral (n = 4) segmental bronchi of the left cranial lobar bronchus, and the left caudal (n = 5) and right middle (n = 2) lobar bronchus. Bronchial collapsibility measurements were greater in the dorsal and ventral segmental bronchi of the left cranial lobar bronchus and the left caudal lobar bronchus (P < 0.001). Findings supported inspiration/expiration CT as a modality to noninvasively assess bronchial collapse in dogs and a bronchial collapsibility value greater than 50% for detecting pathologic bronchial collapse in clinically affected dogs.

Post-pneumonectomy and post-lobectomy syndromes: case series and review of the literature.

The post-pneumonectomy syndrome is a rare complication consisting of rotation and herniation of the mediastinal structures, the remaining lung and the respective bronchi, into the contralateral hemithorax. This situation may produce symptomatic airway obstruction and varies in its presentation and severity. We describe one case of right and one of left pneumonectomy syndrome as well as one case of post-lobectomy syndrome. We review the literature on the pathophysiology, the clinical, radiological and bronchoscopic characteristics of this rare entity and discuss all available therapeutic alternatives.

A 70-Year-Old Man With Cough and Recurrent Respiratory Infections.

CASE PRESENTATION: A 70-year-old man was referred for evaluation of recurrent respiratory infections requiring antibiotics and chronic cough over 3 years. Two months prior to presentation, he started to develop blood-tinged sputum but not frank hemoptysis. He otherwise denied any fever, chills, night sweats, or weight loss. He had dyspnea during the respiratory infections but not otherwise. His medical history was significant for chronic rhinitis without sinusitis and a low serum IgM level. He was a never smoker and a farmer but otherwise had no significant or specific exposures or travel history. His family history was significant for alpha-1 antitrypsin deficiency in his mother.

Bronchial collapsibility at forced expiration in healthy volunteers: assessment with multidetector CT.

PURPOSE: To assess forced-expiratory bronchial collapsibility in healthy volunteers by using multidetector computed tomography (CT) and to compare the results with the current diagnostic criterion for bronchomalacia. MATERIALS AND METHODS: The institutional review board approved this HIPAA-compliant study. Following informed consent, 51 healthy volunteers with normal pulmonary function and no history of smoking were imaged by using a 64-detector row scanner with spirometric monitoring at total lung capacity and during forced exhalation. The total study population (in whom both main bronchi were imaged) included 25 men and 26 women (mean age, 50 years). Each scan was analyzed at a workstation by a fellowship-trained thoracic radiologist. Cross-sectional area measurements were obtained from end-inspiratory and forced-expiratory CT images for the right main bronchus (RMB), left main bronchus, (LMB), and bronchus intermedius (BI), and the mean percentage of expiratory collapse was calculated for each bronchus. The number of participants who exceeded the current diagnostic threshold level (>50% expiratory reduction in cross-sectional area) for bronchomalacia was calculated. Comparisons of airway dimensions and airway collapse according to bronchial segment and sex were made by using repeated-measures analysis of variance. RESULTS: Mean percentage of expiratory collapse was 66.9% ± 19.0 (standard deviation) for the RMB and 61.4% ± 16.7 for the LMB. Thirty-seven (73%) of 51 participants exceeded the diagnostic threshold level for bronchomalacia. Significant differences were observed in mean percentage of expiratory collapse between the RMB (66.9% ± 19.0) and LMB (61.4% ± 16.7) (P = .0005). Among a subgroup of 37 participants in whom the BI was also imaged, the mean percentage of expiratory collapse was 61.8% ± 22.8, and 27 (73%) participants exceeded the diagnostic threshold level for bronchomalacia. CONCLUSION: Healthy volunteers demonstrate a wide range of forced-expiratory bronchial collapse, frequently exceeding the current diagnostic threshold level for bronchomalacia.

Descending Aortopexy and Posterior Tracheopexy for Severe Tracheomalacia and Left Mainstem Bronchomalacia.

Posterior descending aortopexy can relieve posterior intrusion of the left mainstem bronchus that may limit the effectiveness of posterior tracheobronchopexy. We review outcomes of patients undergoing both descending aortopexy and posterior tracheopexy for severe tracheobronchomalacia with posterior intrusion and left mainstem compression to determine if there were resolution of clinical symptoms and bronchoscopic evidence of improvement in airway collapse. All patients who underwent both descending aortopexy and posterior tracheopexy from October 2012 to October 2016 were retrospectively reviewed. Clinical symptoms, tracheomalacia scores based on standardized dynamic airway evaluation by anatomical region, and persistent airway intrusion requiring reoperation were collected. Data were analyzed by Wald and Wilcoxon signed-rank tests. Thirty-two patients underwent descending aortopexy and posterior tracheopexy at median age of 18 months (interquartile range 6-40 months). Median follow-up was 3 months (interquartile range 1-7 months). There were statistically significant improvements in clinical symptoms postoperatively, including cough, noisy breathing, prolonged and recurrent respiratory infections, ventilator dependence, blue spells, and brief resolved unexplained events (all P < 0.001), as well as exercise intolerance (P = 0.033), transient respiratory distress requiring positive pressure (P = 0.003), and oxygen dependence (P = 0.007). Total tracheomalacia scores improved significantly (P < 0.001), with significant segmental improvements in the middle (P = 0.003) and lower (P < 0.001) trachea, and right (P = 0.011) and left (P < 0.001) mainstem bronchi. Two patients (6%) had persistent airway intrusion requiring reoperation with anterior aortopexy or tracheopexy. Descending aortopexy and posterior tracheopexy are effective in treating severe tracheobronchomalacia and left mainstem intrusion with significant improvements in clinical symptoms and degree of airway collapse on bronchoscopy.

Bronchoscopy findings in recurrent croup: A systematic review and meta-analysis.

IMPORTANCE: The etiology of recurrent croup is often anatomic. Currently there is no set criteria for determining who should undergo diagnostic bronchoscopy and which patients are at most risk for having a clinically significant finding. Few studies have addressed these questions. OBJECTIVE: To identify risk factors for clinically significant findings on bronchoscopy in children with recurrent croup and the frequency of bronchoscopy findings in general. DATA SOURCES: PUBMED, Ovid MEDLINE, EMBASE. STUDY SELECTION: Articles addressing bronchoscopy in children with recurrent croup, up to July 2016, were reviewed. Related keywords and medical subject headings were used during the search. The abstracts were reviewed to determine suitability for inclusion based on a set of criteria. Manual crosscheck of references was performed. DATA EXTRACTION: We analyzed the bronchoscopy findings of individual patients in each study and their associated risk factors when available. RESULTS: We reviewed 11 articles, published between 1992 and 2016, including 885 patients (654 males, 237 females). Only 5 studies, including 455 patients, had sufficient data for meta-analysis. Our study revealed that the three most common bronchoscopy findings were subglottic stenosis, reflux changes, and broncho/tracheomalacia. Only 8.7% of patients were noted to have clinically significant findings on bronchoscopy. Meta analysis showed an association between significant bronchoscopy findings and History of Intubation [OR = 5.17, 95% CI 2.65-10.09], Inpatient Consultation [OR = 4.01, 95% CI 1.44-11.20], Age < 3 [OR = 3.22, 95% 1.66-6.27], Age < 1 [OR = 2.86, 95% CI 1.28-6.40], and Prematurity [OR = 2.90, 95% CI 1.39-6.06]. Our study found a high incidence of a History of GERD (20%) and Asthma/Allergies (35%) among patients with recurrent croup, but these variables did not reach statistical significance in patients with significant bronchoscopy findings ([OR = 1.62, 95% CI 0.79-3.30], [OR = 0.57, 95% CI 0.30-1.08] respectively). CONCLUSION: The risk factors most associated with clinically significant bronchoscopy findings in recurrent croup are Intubation, Inpatient Consultation, Age < 3, Age <1, and Prematurity. A History of GERD and Asthma/Allergy, though highly prevalent in recurrent croup patients, were not statistically associated with significant bronchoscopy findings. RELEVANCE: The results should guide physicians in selecting which recurrent croup patients are most at risk for significant findings and thus may warrant bronchoscopy.

Lower airway anomalies in children with CATCH 22 syndrome and congenital heart disease.

OBJECTIVE: CATCH 22 syndrome is a medical acronym for multiple abnormalities, especially cardiac defect. The patients with congenital heart disease (CHD) usually have more complicated post-surgery course. METHODS: We reviewed 4-year experience in our hospital to define the lower airway anomalies and the clinical implications in patients with CATCH 22 syndrome and CHD. From 2004 to 2007, 18 patients who underwent computed tomography for planning of cardiovascular treatment were enrolled. Detection of airway anomalies were performed on computed tomography. RESULTS: Characteristic dysmorphic facial features were noted in 8 out of 18 patients (44%). Ten patients (55.6%) had mild to moderate tracheal or bronchial stenosis. Five patients (28%) had tracheomalacia or bronchomalacia. Comparing to control group, patients received the first major surgery with a median hospital stays of 42 days in study group had a significantly longer hospital stay (42 vs. 16, P = 0.005) and longer duration of ventilator usage (16 vs. 4, P = 0.014). The difference of the mean position of the carina on computed tomography image between study groups and control groups was about three-quarters of a vertebral body height (P < 0.05). CONCLUSIONS: Patients with CATCH 22 syndrome and CHD had a shorter length of trachea compared to that of the age-matched similar CHD. The incidence of associated lower airway anomalies in CHD children with CATCH 22 syndrome was higher. It may lead to longer time of ventilator support after surgery as well as total hospital stays than those of CHD without CATCH 22 syndrome.

Bronchomalacia in dogs with myxomatous mitral valve degeneration.

BACKGROUND: Cough in the geriatric small breed dog with myxomatous mitral valve degeneration (MMVD), a large left atrium, and absence of heart failure often is attributed to compression of the left mainstem bronchus by the left atrium. Studies investigating this syndrome are lacking in dogs. HYPOTHESIS: Airway collapse is independent of left atrial enlargement. ANIMALS: A total of 16 dogs presenting with chronic cough in the absence of congestive heart failure. Group 1 dogs (n = 10) had moderate-to-severe left atrial enlargement based on an echocardiographically calculated left atrial:aortic surface area [LA:Ao(a)] > 6. Group 2 dogs (n = 6) had no to mild left atrial enlargement [LA:Ao(a) ≤ 6]. METHODS: Dogs were prospectively evaluated. CBC, biochemistry, urinalysis, cervical and thoracic radiographs, fluoroscopy, echocardiography, and bronchoscopy were performed. Bronchoscopic abnormalities were compared between groups using Fisher's Exact Test. P < .05 was considered significant. RESULTS: Fluoroscopy identified airway collapse in both groups. Bronchoscopic evidence of airway collapse >50% was observed in multiple bronchi with no difference between groups. All dogs had inflammation on airway cytology with respiratory infection in 1 dog in group 2. Left atrial size was interpreted radiographically as enlarged in 9 of 10 group 1 dog and in 2 of 6 group 2 dogs. VHS was above normal in both groups of dogs regardless of echocardiographic evidence of cardiomegaly. CONCLUSIONS: Results failed to identify an association between left atrial enlargement and airway collapse in dogs with MMVD, but did suggest that airway inflammation is common in dogs with airway collapse.