BACKGROUND: Patients with airway stenosis (AS) are associated with considerable morbidity and mortality after lung transplantation (LTx). This study aims to develop and validate machine learning (ML) models to predict AS requiring clinical intervention in patients after LTx.
METHODS: Patients who underwent LTx between January 2017 and December 2019 were reviewed. The conventional logistic regression (LR) model was fitted by the independent risk factors which were determined by multivariate LR. The optimal ML model was determined based on 7 feature selection methods and 8 ML algorithms. Model performance was assessed by the area under the curve (AUC) and brier score, which were internally validated by the bootstrap method.
RESULTS: A total of 381 LTx patients were included, and 40 (10.5%) patients developed AS. Multivariate analysis indicated that male, pulmonary arterial hypertension, and postoperative 6-min walking test were significantly associated with AS (all P < 0.001). The conventional LR model showed performance with an AUC of 0.689 and brier score of 0.091. In total, 56 ML models were developed and the optimal ML model was the model fitted using a random forest algorithm with a determination coefficient feature selection method. The optimal model exhibited the highest AUC and brier score values of 0.760 (95% confidence interval [CI], 0.666-0.864) and 0.085 (95% CI, 0.058-0.117) among all ML models, which was superior to the conventional LR model.
CONCLUSIONS: The optimal ML model, which was developed by clinical characteristics, allows for the satisfactory prediction of AS in patients after LTx.

This study aimed to design a standardised bronchoscopic holmium laser ablation continuous cryoablation for the treatment of airway stenosis caused by tissue hyperplasia after tracheal intubation and to retrospectively analyse its safety and feasibility. We collected the data of patients who had undergone bronchoscopic holmium laser ablation continuous cryoablation due to airway stenosis caused by tracheal mucosal tissue hyperplasia after tracheal intubation. The patients\' baseline characteristics, ablation effects, surgical complications and other data were analysed. In total, 16 patients were enrolled in this study. On average, airway stenosis occurred 96.00 (interquartile range, 69.75-152.50) days after tracheal intubation and bronchoscopic holmium laser ablation continuous cryoablation took an average of 90.38 minutes (standard deviation: 16.78). After the first continuous cryoablation, 75.0% (12/16) of the patients had complete ablation of hyperplastic tissue, and 25.0% (4/16) had most of the hyperplastic tissue (>50%) removed. Altogether, 18.75% (3/16) and 6.25% (1/16) of the patients had complete ablation of hyperplastic tissue after the second and third cryoablation, respectively. Moreover, one patient (6.25%) had minimal wound bleeding postoperatively, and no other surgical complications occurred. No airway stenosis was found in all enrolled patients during follow-up 1 and 6 months after the last cryoablation. According to the above results of our small sample study indicated that bronchoscopic holmium laser ablation continuous cryoablation seems safe and effective for treating airway stenosis caused by tissue hyperplasia after tracheal intubation.

The tracheal Y-shaped stent is mainly used for the treatment of critical patients with airway stenosis or esophagotracheal fistula near carina. A novel method for precise implantation of Y-shaped tracheal stents was developed using double-lumen endotracheal intubation and flexible bronchoscopy. This approach aims to address the limitations associated with X-ray or rigid bronchoscopy guidance, such as operational difficulties and the risk of inaccurate stent placement leading to implantation failure or suffocation. With this new technique, 13 tracheal Y-shaped stents were successfully implanted. This method shows promise in reducing the complexity of stent implantation and facilitating timely treatment for patients in need. Additionally, it has the potential to update current operating standards and guidelines for this procedure.

UNASSIGNED: This study aimed to investigate the safety and efficacy of transarterial infusion chemotherapy for the treatment of esophageal cancer with airway stenosis.
UNASSIGNED: Data of patients with advanced esophageal cancer complicated with airway stenosis treated with transarterial infusion chemotherapy were retrospectively analyzed. Dyspnea, clinical efficacy and adverse reactions were evaluated.
UNASSIGNED: Of these patients, 27 had grade II preoperative dyspnea, and 31 had grade III preoperative dyspnea, 26 had grade I postoperative dyspnea, 25 had grade II postoperative dyspnea, and 7 had grade III postoperative dyspnea. Among 3 patients with left main bronchial stenosis and atelectasis, 2 had complete remission after transarterial infusion chemotherapy, and 1 demonstrated partial remission. After treatment, complete response, partial response, and stable disease were observed in 7, 34, and 17 cases, respectively. Total objective effective rate and disease control rate were 70.6% (41/58) and 100.0%, respectively. During follow up, 24 patients died of organ failure, and 17 patients died of tumor-related respiratory failure. Seven patients died of gastrointestinal bleeding, 1 patient died of myocardial infarction, and 9 patients survived.
UNASSIGNED: Transarterial infusion chemotherapy is safe and effective for the treatment of advanced esophageal cancer with airway stenosis.

This study focused on congenital heart disease (CHD) patients complicated with airway stenosis (AS) without airway intervention and aimed to identify the patients with potential risks.
Patients diagnosed with CHD and AS were enrolled in this retrospective study. The primary outcome was defined as a postoperative mechanical ventilation duration of more than two weeks. We constructed a prediction model to predict the risk of prolonged mechanical ventilation (PMV).
A total of 185 patients diagnosed with CHD and AS in Fuwai Hospital from July 2009 to December 2022 were included in the study. Weight at CHD surgery, cardiopulmonary bypass (CPB) duration, complex CHD and comorbid tracheobronchomalacia were identified as risk factors and included in the model. The ROC curve showed a good distinguishing ability, with an AUC of 0.847 (95% CI: 0.786-0.908). According to the optimal cut-off value of the ROC curve, patients were divided into high- and low-risk groups, and the subsequent analysis showed significant differences in peri-operative characteristics and in-hospital deaths.
With the predictive model, several factors could be used to assess the risky patients with PMV. More attention should be paid to these patients by early identification and routine surveillance.

Airway stent insertion is important for patients with airway stenosis. Currently, the most widely used airway stents in clinical procedures are silicone and metallic stents, which offer patients effective treatment. However, these stents composed of permanent materials need to be removed, subjecting patients to invasive manipulation once more. As a result, there is a growing demand for biodegradable airway stents. Biodegradable materials for airway stents are now available in two types: biodegradable polymers and biodegradable alloys. Polymers that include poly (l-lactic acid), poly (D, l-lactide-co-glycolide), polycaprolactone, and polydioxanone are the ultimate metabolites which are generally carbon dioxide and water. Magnesium alloys are the most often utilized metal biodegradable materials for airway stents. The stent\'s mechanical properties and rate of degradation vary as a result of the different materials, cutting techniques, and structural configurations. We summarized the information above from recent studies on biodegradable airway stents conducted in both animals and humans. There is great potential for clinical applications for biodegradable airway stents. They avoid damage to the trachea during removal and reduce complications to some extent. However, several significant technical difficulties slow down the development of biodegradable airway stents. The efficacy and safety of different biodegradable airway stents still need to be investigated and proved.

UNASSIGNED: Extracorporeal membrane oxygenation (ECMO) is widely used during refractory cardiac or respiratory failure, and some case reports described ECMO utilization in critical airway interventional therapy.
UNASSIGNED: Eligible reports about patients receiving airway interventional therapy under ECMO were retrieved from Web of Science, Embase, Medline, and Cochrane databases up to 1 August 2022.
UNASSIGNED: Forty-eight publications including 107 patients who underwent ECMO for critical airway problems met the inclusion criteria. The critical airway problem that was reported the most was tumor-associated airway obstruction (n = 66, 61.7%). The second most reported etiology was postoperative airway collapse or stenosis (n = 19, 17.8%). The main interventional therapies applied were airway stent placement or removal (n = 61, 57.0%), mass removal (n = 22, 20.6%), and endotracheal intubation (n = 12, 11.2%) by bronchoscopy. The median ECMO duration was 39.5 hours. Eleven patients had ECMO-associated complications, including seven cases of airway hemorrhage, one case of arteriovenous fistula, one case of vein rupture and hematoma, one case of foot ischemia, and one case of neuropraxia of the cannulation site. In total, 91.6% of the patients survived and were discharged from the hospital.
UNASSIGNED: ECMO appears to be a viable form of life support for patients undergoing interventional therapy for critical airway problems.

The indications and surgical techniques for airway stenosis (AS) repair among patients with bridging bronchus (BB) and congenital heart disease (CHD) have not been fully established. We sought to provide our experience with tracheobronchoplasty in a large series of BB patients with AS and CHD. Eligible patients were retrospectively enrolled from June 2013 to December 2017 and were followed up to December 2021. Epidemiological, demographic, clinical, imaging, surgical management, and outcome data were obtained. 5 tracheobronchoplasty techniques including 2 novel modified ones were performed. We included 30 BB patients with AS and CHD. Tracheobronchoplasty was indicated in them. 27 (90%) patients underwent tracheobronchoplasty. But 3 (10%) refused AS repair. 4 subtypes of the BB and 5 main sites of AS were identified. 6 (22.2%) cases, including one death, had severe postoperative complications associated with being underweight at surgery, preoperative mechanical ventilation, and more types of CHD. 3 cases were lost to follow-up. 18 (78.3%) of the survivors remained asymptomatic, and 5 (21.7%) had stridor, wheezing, or polypnea after exercise. 2 patients out of the three who did not undergo airway surgery died, and the one survivor had a poor quality of life. Good outcomes can be achieved in BB patients with AS and CHD who undergo proper tracheobronchoplasty techniques guided by specified criteria, but severe postoperative complications should be well managed.

BACKGROUND: The insertion of self-expandable metallic stents (SEMS) for post-tuberculosis tracheobronchial stenosis (PTTS) was controversial. This study aimed to evaluate the efficacy and safety of SEMS for treating PTTS, and developed a scoring system for predicting the occurrence of restenosis after stenting in PTTS patients.
METHODS: We conducted a retrospective review of 87 patients who were diagnosed with PTTS and experienced SEMS insertion between January 2000 and December 2017. All procedures were performed via flexible bronchoscopy under conscious sedation and local anesthesia.
RESULTS: A total of 85 SEMS were successfully placed in 77 patients. Comparing with pre-stenting, there were significant improvements in the lumen diameters of the stenotic segment, mMRC scale and lung function after short-term SEMS placement. During the long-term (average 163.32 months) follow-up, 48 patients (62.3%) did not develop restenosis after stenting; the other 29 patients (37.7%) developed and eventually, 12 remained under interventional therapies and 11 had bronchial atresia. Multivariate Cox regression analysis revealed that the difference value between SEMS length and the stenosis-segment length, stenosis type, and the number of pre-stenting thermal ablation were independently related to restenosis occurrence and were subsequently used to establish the Restenosis Score. The model\'s development group (0.83, 95% CI 0.74-0.92) and external validation set (0.94, 95% CI 0.77-1.00) showed excellent discrimination.
CONCLUSIONS: SEMS placement could serve as a safe and effective treatment option for most patients with PTTS. Further, we built a prediction model depending on the independent predictors of restenosis occurrence, the Restenosis Score. This validated tool might provide a decision support and a better management for PTTS patients who underwent SEMS implantation.

UNASSIGNED: Airway stents, used to restore airway patency, are mostly utilized by patients with malignant airway strictures, and are occasionally used in a range of other airway related diseases, including conditions which result in benign stenosis, malacia, and fistula. There has been an increasing number of airway stents that are being developed thanks to improvements in interventional therapy. However, the method of promoting airway stents for clinical application remains undetermined. Herein, we describe the recent advances in airway stents by reviewing the published studies, providing the reference for clinical decision-making and further research on airway stents.
UNASSIGNED: Relevant articles between January 1964 and November 2021 were obtained from PubMed, Web of Science, and EMBASE databases. The terms \"metallic\", \"silicone\", \"drug-eluting\", \"biodegradable\", \"radioactive\", \"three-dimensional (3D)\", and \"stents\" were searched in different combinations.Key Content and Findings: In this review, we focus on the latest evidence in terms of the application of various stents with novel materials and designs including novel metallic, novel silicone, drug-eluting, biodegradable, radioactive, and 3D stents for airway stenosis. Despite reducing the well-known complications of all current commercially available stents, novel stents are still in their infancy without a long track record of utility and safety, and remain some limitations. There are more steps to be taken before such stents enter routine clinical practice.
UNASSIGNED: A combination of 3D-printing method and biodegradable material may present a promising avenue of solving the existing problems pertaining to \"classic\" stents and has potential to become the main trend in the future.