BACKGROUND: Tracheal collapse (TC), a common disease in dogs, is characterized by cough; however, little is known about the serum biomarkers that can objectively evaluate the severity of cough in canine TC. Furthermore, studies elucidating the relationship of fluoroscopic characteristics with the severity of cough are lacking. Therefore, this study aimed to evaluate the relationship between cough severity and clinical characteristics, fluoroscopic images, and new serum biomarkers in canine TC.
RESULTS: Fifty-one client-owned dogs diagnosed with TC based on fluoroscopic and clinical signs were enrolled in this study and divided into three groups according to the severity of cough (grade of cough: 0, 1, and 2). Signalments, comorbidities, and fluoroscopic characteristics were compared among the groups retrospectively. The serum matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), surfactant protein-A (SP-A), and syndecan-1 (SDC-1) levels were measured in all groups. No significant differences in age, breed, sex, or clinical history were observed among the groups. Concomitant pharyngeal collapse increased significantly with the severity of cough (p = .031). Based on the fluoroscopic characteristics, the TC grade of the carinal region increased significantly and consistently with the grade of cough (p = .03). The serum MMP-9 level was significantly higher in the grade 2 group than that in the grade 0 group (p = .014). The serum IL-6 level was significantly lower in the grade 1 group than that in the grade 0 group (p = .020). The serum SP-A and SDC-1 levels did not differ significantly among the groups.
CONCLUSIONS: The severity of cough with the progression of TC can be predicted with the fluoroscopic TC grade at the carinal region. MMP-9 may be used as an objective serum biomarker that represents cough severity to understand the pathogenesis.

OBJECTIVE: Bethanechol has demonstrated improvement in trachealis tone in animal models, but no trials have studied efficacy in infants. This study aimed to examine if bethanechol improves a standardized pulmonary severity score (PSS) in infants with severe bronchopulmonary dysplasia with a diagnosis of tracheobronchomalacia (TBM).
METHODS: This retrospective cohort study evaluated cases treated with bethanechol matched with controls who did not receive bethanechol. TBM was diagnosed by dynamic computography. Daily PSS was recorded for each infant from 40 to 55 weeks post-menstrual age.
RESULTS: Cases\' mean PSS change was 21% lower than the controls\' mean PSS change pre- and post-bethanechol (95% CI -40%, -2%) by paired t-test (p = 0.03). Matched differences (controls\' PSS - cases\' PSS) demonstrated greater mean PSS difference post-bethanechol compared to pre-bethanechol 0.17, (95% CI 0.05, 0.29) by paired t-test (p = 0.009).
CONCLUSIONS: Infants with TBM treated with bethanechol compared to those not treated had a lower PSS reflecting improved respiratory status.

Tracheobronchial stenosis, particularly central airway stenosis, which frequently results in severe complications such as lung damage, occurs in patients with tracheobronchial tuberculosis (TBTB).
To analyze the clinical characteristics of patients with central airway stenosis due to tuberculosis (CASTB).
Retrospective analysis was performed on the clinical features, radiological features, bronchoscopic features and treatment of 157 patients who were diagnosed with CASTB in two tertiary hospitals in Chongqing, China, from May 2020 to May 2022.
CASTB mostly occurs in young patients and females. Patients with CASTB exhibited different symptoms repeatedly during the disease, especially varying degrees of dyspnea, prompting many patients to undergo bronchoscopic intervention and even surgery. Patients with cicatricial strictures constituted the highest proportion of the TBTB subtype with CASTB and 35.7% of the patients with CASTB were found to have tracheobronchomalacia (TBM) under bronchoscopy. CASTB and TBM mainly involved the left main bronchus. Patients with lower levels of education had higher rates of TBM. Patients with TBM manifested shortness of breath more frequently than patients without TBM. Patients with TBTB who had undergone bronchoscopic interventions have a higher rate of TBM.
Despite mostly adequate anti-tuberculosis chemotherapy, patients with TBTB can present with CASTB involving severe scarring stenosis, bronchial occlusion, tracheobronchomalacia and even destroyed lung.

Tracheobronchomalacia (TBM) is common in neonates with bronchopulmonary dysplasia (BPD) and is associated with higher morbidity. This study evaluates the value of a CT protocol to assess the degree of TBM and gauge the adequacy of prescribed PEEP.
Four infants with severe BPD on invasive mechanical ventilation underwent a chest CT protocol, including limited reduced-dose expiratory scans with varying PEEP levels.
Baseline PEEP was adjusted in all subjects after performing the Dynamic PEEP CT. In two infants, the PEEP was increased due to significant TBM and in the other two without signs of TBM PEEP was decreased. The clinical course improved in all patients after adjusting PEEP.
A \"Dynamic PEEP\" study may be reliable and non-invasive imaging modality for the evaluation of adequate ventilator settings in infants with severe BPD who are not optimal candidates for bronchoscopy.

BACKGROUND: Mounier-Kuhn syndrome or congenital tracheobronchomegaly is a rare disease characterized by dilation of the trachea and the main bronchi within the thoracic cavity. The predominant signs and symptoms of the disease include coughing, purulent and abundant expectoration, dyspnea, snoring, wheezing, and recurrent respiratory infection. Symptoms of the disease in some patients are believed to be pathological manifestations arising due to resident tracheobronchomalacia. Although treatment options used for the management of this disease include inhaled bronchodilators, corticosteroids, and hypertonic solution, there is no consensus on the treatment. The use of continuous positive airway pressure (CPAP) has been reported as a potential therapeutic option for tracheobronchomalacia, but no prospective studies have demonstrated its efficacy in this condition.
OBJECTIVE: The purpose of this is to identify the presence of tracheobronchomalacia and an optimal CPAP pressure that reduces the tracheobronchial collapse in patients with Mounier-Kuhn syndrome and to analyze the repercussion in pulmonary ventilation. In parallel, we aim to evaluate the prevalence of obstructive sleep apnea/hypopnea syndrome.
METHODS: This interventional, open-label, single-arm clinical trial will enroll patients who are diagnosed Mounier-Kuhn syndrome. Patient evaluation will be conducted in an outpatient clinic and involve 3 visits. Visit 1 will involve the collection and registration of social demographic, clinical, and functional data. Visit 2 will entail polysomnography, bronchoscopy for the evaluation of tracheobronchomalacia, titration of the optimal pressure that reduces the degree of collapse of the airway, and electrical impedance tomography. In visit 3, patients exhibiting a reduction in collapse areas will be requested to undergo chest computed tomography during inspiration and forced expiration with and without positive pressure (titrated to determine optimal CPAP pressure).
RESULTS: This protocol is a doctorate project. The project was submitted to the institutional review board on January 24, 2017, and approval was granted on February 2, 2017 (Brazilian Research database number CAAE 64001317.4.000.0068). Patient evaluations started in April 2018. Planned recruitment is based on volunteers\' availability and clinical stability, and interventions will be conducted at least once a month to finish the project at the end of 2020. A preliminary analysis of each case will be performed after each intervention, but detailed results are expected to be reported in the first quarter of 2021.
CONCLUSIONS: There is no consensus on the best treatment options for managing Mounier-Kuhn syndrome. The use of positive pressure could maintain patency of the collapsed airways, functioning as a \"pneumatic stent\" to reduce the degree of airflow obstruction. This, in turn, could promote mobilization of thoracic secretion and improve pulmonary ventilation.
BACKGROUND: ClinicalTrails.gov NCT03101059; https://clinicaltrials.gov/ct2/show/NCT03101059.
UNASSIGNED: DERR1-10.2196/14786.

OBJECTIVE: Dynamic chest radiography (DCR) can observe the dynamic structure of the chest using continuous pulse fluoroscopy irradiation. However, its usefulness remains largely undetermined. The purpose of this study was to examine the relationship between changes in tracheal diameter during deep breathing and obstructive ventilation disorders using DCR.
METHODS: Twelve participants with obstructive ventilatory impairment and 28 with normal pulmonary function underwent DCR during one cycle of deep inspiration and expiration. Three evaluators blinded to pulmonary function test results independently measured lateral diameters of the trachea in DCR images to determine whether there was a difference in the amount of change in tracheal diameter depending on the presence or absence of pulmonary dysfunction. Tracheal narrowing was defined as a decrease in the lateral tracheal diameter of more than 30 %. Participants were divided into a narrowing group and a non-narrowing group, and it was examined whether each group correlated with values of pulmonary function tests.
RESULTS: Tracheal diameter was significantly narrowed in subjects with obstructive ventilatory impairment compared to normal subjects (P <  0.01). When subjects were divided into narrowing (tracheal narrowing rate [TNr] = 41.5 ± 7.7 %, n = 9) and non-narrowing groups (TNr = 9.1 ± 7.0 %, n = 31, p < 0.01), FEV1%-G, and %V25 were significantly smaller in the narrowing group than in the non-narrowing group (p < 0.01).
CONCLUSIONS: Changes in tracheal diameter during deep breathing were easily evaluated using DCR. DCR may, therefore, be useful for evaluating obstructive ventilation disorders.

BACKGROUND: Tracheobronchoplasty is the definitive treatment for patients with symptomatic excessive central airway collapse. This procedure is associated with high morbidity and mortality rates. Bronchoscopic techniques are an appealing alternative with less morbidity and the ability to apply it in nonsurgical patients. Although thermoablative methods have been proposed as treatment options to induce fibrosis of the posterior tracheobronchial wall, no studies have compared direct histologic effects of such methods. This study compared the effects of electrocautery, radiofrequency ablation, potassium titanyl phosphate laser, and argon plasma coagulation (APC) in the tracheobronchial tree in an ex vivo animal model.
METHODS: Four adult sheep cadavers were used for this study. Under flexible bronchoscopy, the posterior tracheal membrane was treated using different power settings on 4 devices. The airways were assessed for the presence of treatment-related histopathologic changes.
RESULTS: Histologic changes observed were that of acute thermal injury including: surface epithelium ablation, collagen fiber condensation, smooth muscle cytoplasm condensation, and chondrocyte pyknosis. No distinct histologic differences in the treated areas among different modalities and treatment effects were observed. APC at higher power settings was the only modality that produced consistent and homogenous thermal injury effects across all tissue layers with no evidence of complete erosion.
CONCLUSIONS: Although electrocautery, radiofrequency ablation, potassium titanyl phosphate laser, and APC all induce thermal injury of the airway wall, only APC at high power settings achieves this effect without complete tissue erosion, favoring potential regeneration and fibrosis. Live animal studies are now plausible.

Anatomically complex airway stenosis (ACAS) represents a challenging situation in which commercially available stents often result in migration or granulation tissue reaction due to poor congruence. This proof-of-concept clinical trial investigated the feasibility and safety of computer-assisted designed (CAD) and manufactured personalised three-dimensional (3D) stents in patients with ACAS from various origins. After CAD of a virtual stent from a CT scan, a mould is manufactured using a 3D computer numerical control machine, from which a medical-grade silicone stent is made. Complication rate, dyspnoea, quality of life and respiratory function were followed after implantation. The congruence of the stent was assessed peroperatively and at 1 week postimplantation (CT scan). The stent could be implanted in all 10 patients. The 3-month complication rate was 40%, including one benign mucus plugging, one stent removal due to intense cough and two stent migrations. 9 of 10 stents showed great congruence within the airways, and 8 of 10 induced significant improvement in dyspnoea, quality of life and respiratory function. These promising outcomes in highly complex situations support further investigation on the subject, including technological improvements.​ TRIAL REGISTRATION NUMBER: NCT02889029.

暂无摘要。

BACKGROUND: Tracheobronchomalacia (TBM) refers to a condition in which structural integrity of cartilaginous wall of trachea is lost. Excessive dynamic airway collapse (EDAC) is characterized by excessive invagination of posterior wall of trachea. In both these conditions, airway lumen gets compromised, especially during expiration, which can lead to symptoms such as breathlessness, cough, and wheezing. Both these conditions can be present in obstructive lung diseases; TBM due to chronic airway inflammation and EDAC due to dynamic compressive forces during expiration. The present study was planned with the hypothesis that TBM/EDAC could also produce expiratory wheeze in patients with obstructive airway disorders. Hence, prevalence and factors affecting presence of this entity in patients with obstructive airway diseases were the aims and objectives of this study.
METHODS: Twenty-five patients with obstructive airway disorders (chronic obstructive pulmonary disease [COPD] or bronchial asthma), who were stable on medical management, but having persistent expiratory wheezing, were included in the study. They were evaluated for TBM/EDAC by bronchoscopy and computed tomographic scan of chest. The presence of TBM/EDAC was correlated with variables including age, sex, body mass index (BMI), smoking index, level of dyspnea, and severity of disease.
RESULTS: Mean age of the patients was 62.7 ± 7.81 years. Out of 25 patients, 14 were males. TBM/EDAC was found in 40% of study subjects. Age, sex, BMI, severity of disease, frequency of exacerbations and radiological findings etc., were not found to have any association with presence of TBM/EDAC.
CONCLUSIONS: TBM/EDAC is common in patients with obstructive airway disorders and should be evaluated in these patients, especially with persistent expiratory wheezing as diagnosis of this entity could provide another treatment option in these patients with persistent symptoms despite medical management.