Management of Central Airway Obstruction: An American College of Chest Physicians Clinical Practice Guideline.

BACKGROUND: Central airway obstruction (CAO), seen in a variety of malignant and non-malignant airway disorders, is associated with a poor prognosis. The management of CAO is dependent on provider training and local resources, which may make the clinical approach and outcomes highly variable. We reviewed the current literature and provided evidence-based recommendations for the management of CAO. METHODS: A multidisciplinary expert panel developed key questions using the PICO (Patient, Intervention, Comparator, and Outcomes) format and conducted a systematic literature search using MEDLINE (PubMed) and the Cochrane Library. The panel screened references for inclusion and used vetted evaluation tools to assess the quality of included studies and extract data, and graded the level of evidence supporting each recommendation. A modified Delphi technique was used to reach consensus on recommendations. RESULTS: A total of 9,688 abstracts were reviewed, 150 full-text articles were assessed, and 31 studies were included in the analysis. One good practice statement and 10 graded recommendations were developed. The overall certainty of evidence was very low. CONCLUSIONS: Therapeutic bronchoscopy can improve the symptoms, quality of life, and survival of patients with malignant and non-malignant CAO. Multi-modality therapeutic options, including rigid bronchoscopy with general anesthesia, tumor/tissue debridement, ablation, dilation, and stent placement, should be utilized when appropriate. Therapeutic options and outcomes are dependent on the underlying etiology of CAO. A multidisciplinary approach and shared decision-making with the patient are strongly encouraged.

Graphene oxide-loaded rapamycin coating on airway stents inhibits stent-related granulation tissue hyperplasia.

OBJECTIVES: Our objective was to explore the safety and efficacy of a graphene oxide-loaded rapamycin-coated self-expandable metallic airway stent (GO@RAPA-SEMS) in a rabbit model. METHODS: The dip coating method was used to develop a GO@RAPA-SEMS and a poly(lactic-co-glycolic)-acid loaded rapamycin-coated self-expandable metallic airway stent (PLGA@RAPA-SEMS). The surface structure was evaluated using a scanning electronic microscope. The in vitro drug-release profiles of the 2 stents were explored and compared. In the animal study, a total of 45 rabbits were randomly divided into 3 groups and underwent 3 kinds of stent placements. Computed tomography was performed to evaluate the degree of stenosis at 1, 2 and 3 months after the stent operation. Five rabbits in each group were sacrificed after the computed tomography scan. The stented trachea and blood were collected for further pathological analysis and laboratory testing. RESULTS: The in vitro drug-release study revealed that GO@RAPA-SEMS exhibited a sudden release on the first day and maintained a certain release rate on the 14th day. The PLGA@RAPA-SEMS exhibited a longer sustained release time. All 45 rabbits underwent successful stent placement. Pathological results indicated that the granulation tissue thickness in the GO@RAPA-SEMS group was less than that in the PLGA@RAPA-SEMS group. The TUNEL and hypoxia-inducible factor-1α staining results support the fact that the granulation inhibition effect in the GO@RAPA-SEMS group was greater than that in the PLGA@RAPA-SEMS group. CONCLUSIONS: GO@RAPA-SEMS effectively inhibited stent-related granulation tissue hyperplasia.

Computational Analysis of Polymeric Biodegradable and Customizable Airway Stent Designs.

The placement of endotracheal prostheses is a procedure used to treat tracheal lesions when no other surgical options are available. Unfortunately, this technique remains controversial. Both silicon and metallic stents are used with unpredictable success rates, as they have advantages but also disadvantages. Typical side effects include restenosis due to epithelial hyperplasia, obstruction and granuloma formation. Repeat interventions are often required. Biodegradable stents are promising in the field of cardiovascular biomechanics but are not yet approved for use in the respiratory system. The aim of the present study is to summarize important information and to evaluate the role of different geometrical features for the fabrication of a new tracheo-bronchial prosthesis prototype, which should be biodegradable, adaptable to the patient's lesion and producible by 3D printing. A parametric design and subsequent computational analysis using the finite element method is carried out. Two different stent designs are parameterized and analyzed. The biodegradable material chosen for simulations is polylactic acid. Experimental tests are conducted for assessing its mechanical properties. The role of the key design parameters on the radial force of the biodegradable prosthesis is investigated. The computational results allow us to elucidate the role of the pitch angle, the wire thickness and the number of cells or units, among other parameters, on the radial force. This work may be useful for the design of ad hoc airway stents according to the patient and type of lesion.

Analyzing the characteristics of respiratory microbiota after the placement of an airway stent for malignant central airway obstruction.

Malignant central airway stenosis is treated with airway stent placement, but post-placement microbial characteristics remain unclear. We studied microbial features in 60 patients post-stent placement, focusing on changes during granulation tissue proliferation. Samples were collected before stent (N = 29), after stent on day 3 (N = 20), and after granulation tissue formation (AS-GTF, N = 43). Metagenomic sequencing showed significant respiratory tract microbiota changes with granulation tissue. The microbiota composition, dominated by Actinobacteria, Firmicutes, and Proteobacteria, was similar among the groups. At the species level, the AS-GTF group exhibited significant differences, with Peptostreptococcus stomatis and Achromobacter xylosoxidans enriched. Analysis based on tracheoesophageal fistula presence identified Tannerella forsythia and Stenotrophomonas maltophilia as the main differential species, enriched in the fistula subgroup. Viral and fungal detection showed Human gammaherpesvirus 4 and Candida albicans as the main species, respectively. These findings highlight microbiota changes after stent placement, potentially associated with granulation tissue proliferation, informing stent placement therapy and anti-infective treatment optimization. IMPORTANCE: Malignant central airway stenosis is a life-threatening condition that can be effectively treated with airway stent placement. However, despite its clinical importance, the microbial characteristics of the respiratory tract following stent insertion remain poorly understood. This study addresses this gap by investigating the microbial features in patients with malignant central airway stenosis after stent placement, with a specific focus on microbial changes during granulation tissue proliferation. The findings reveal significant alterations in the diversity and structure of the respiratory tract microbiota following the placement of malignant central airway stents. Notably, certain bacterial species, including Peptostreptococcus stomatis and Achromobacter xylosoxidans, exhibit distinct patterns in the after-stent granulation tissue formation group. Additionally, the presence of tracheoesophageal fistula further influences the microbial composition. These insights provide valuable references for optimizing stent placement therapy and enhancing clinical anti-infective strategies.

Airway stenting for liberation from positive pressure ventilation in patients with central airway obstruction presenting with acute respiratory failure.

BACKGROUND: Central airway obstruction (CAO) can lead to acute respiratory failure (RF) necessitating positive pressure ventilation (PPV). The efficacy of airway stenting to aid liberation from PPV in patients with severe acute RF has been scarcely published. We present a systematic review and our recent experience. METHODS: A systematic review of PubMed was performed, and a retrospective review of cases performed at our two institutions from 2018 to 2022 in adult patients who needed stent insertion for extrinsic or mixed CAO complicated by RF necessitating PPV. RESULTS: Fifteen studies were identified with a total of 156 patients. The weighted mean of successful liberation from PPV post-stenting was 84.5% and the median survival was 127.9 days. Our retrospective series included a total of 24 patients. The most common etiology was malignant CAO (83%). The types of PPV used included high-flow nasal cannula (HFNC) (21%), non-invasive ventilation (NIV) (17%) and Invasive Mechanical Ventilation (62%). The overall rate of successful liberation from PPV was 79%, with 55% of HFNC and NIV cases being liberated immediately post-procedure. The median survival of the patients with MCAO that were successfully liberated from PPV was 74 days (n = 16, range 3-893 days), and for those with that failed to be liberated from PPV, it was 22 days (n = 4, range 9-26 days). CONCLUSION: In patients presenting with acute RF from extrinsic or mixed morphology CAO requiring PPV, airway stenting can successfully liberate most from the PPV. This may allow patients to receive pathology-directed treatment and better end-of-life care.

Lung transplant airway complications treated with biodegradable airway stents: The Dutch multi-center experience.

INTRODUCTION: Treatment of post lung-transplant airway complications is challenging, and treatment with conventional airway stents is associated with adverse events. More recently, biodegradable airway stents (BDS) have been introduced and may be used to reduce these adverse events. In this study we explore the feasibility of treatment with BDS post lung transplant. METHODS: All patients treated with BDS in The Netherlands were included in this retrospective multicenter study. Feasibility, life span of the stent, occurrence of adverse events, and evolution of lung function were evaluated. RESULTS: Twelve patients (six malacia and six stenosis) received a total of 57 BDS, ranging from 1 to 10 BDS per patient. Six patients had been pretreated with conventional airway stents. Median stent life span was 112 days (range 66-202). No adverse events occurred during stent placement. In 5 out of 57 stent placements, a single additional bronchoscopy was necessary because of mucus accumulation (n = 4) or excessive granulation tissue (n = 1). All stent naïve patients became airway stent independent after treatment; all patients pretreated with conventional airway stents were still airway stent dependent at the end of follow up. CONCLUSION: Treatment with BDS is safe and feasible. Adverse events were mild and easily treatable. All patients with initial treatment with BDS were airway stent independent at the end of follow up with a median treatment of 4 BDS.

Efficacy of airway stenting and nasogastric tube insertion in airway-esophageal fistula patients with airways compromised by advanced malignancy.

INTRODUCTION: Whether airway-compromised airway-esophageal fistula (AEF) patients should undergo combined airway and esophageal stenting is controversial. This study was designed to evaluate the survival prognosis and poststent interventions in AEF patients with airways compromised by advanced malignancy with or without airway stents. METHODS: A retrospective analysis of the medical records, survival times, and poststent interventions of 17 patients with or without airway stents was performed. RESULTS: The causes of AEF were esophageal cancer (11/17, 64.7%), lung cancer (6/17, 29.4%), and thyroid cancer (1/17, 5.9%). All patients received a nasogastric tube (n = 12) or underwent gastrostomy (n = 5) to resume enteral nutrition. Thirteen patients underwent airway stent insertion (13/17, 76.5%), whereas four patients did not. Four patients with a high risk of stent migration received external stent fixation to the trachea. Three of the patients with stents suffered severe granulation tissue formation and needed repeated bronchoscopy interventions. In the stented group, none of the patients developed stent migration, and the overall median survival time was 9 months, compared with 1.25 months in the nonstented group (P = 0.04). Cox proportional hazards regression revealed that stent insertion, nasogastric tube insertion, and transcatheter bronchial artery chemoembolization were protective factors against death, whereas surgery-related fistula, fistula larger than 2 cm, continued chemotherapy, and age were risk factors for poor survival (P < 0.05). CONCLUSION: In airway-compromised AEF patients, airway stents and nasogastric tubes are probably the preferred treatments. Airway stenting is tolerable, and routine weekly poststent bronchoscopy is needed in the first month and depending on respiratory symptoms thereafter.

Three Decades Single Center Experience of Airway Complications After Lung Transplantation.

Post lung transplantation airway complications like necrosis, stenosis, malacia and dehiscence cause significant morbidity, and are most likely caused by post-operative hypo perfusion of the anastomosis. Treatment can be challenging, and airway stent placement can be necessary in severe cases. Risk factors for development of airway complications vary between studies. In this single center retrospective cohort study, all lung transplant recipients between November 1990 and September 2020 were analyzed and clinically relevant airway complications of the anastomosis or distal airways were identified and scored according to the ISHLT grading system. We studied potential risk factors for development of airway complications and evaluated the impact on survival. The treatment modalities were described. In 651 patients with 1,191 airway anastomoses, 63 patients developed 76 clinically relevant airway complications of the airway anastomoses or distal airways leading to an incidence of 6.4% of all anastomoses, mainly consisting of airway stenosis (67%). Development of airway complications significantly affects median survival in post lung transplant patients compared to patients without airway complication (101 months versus 136 months, p = 0.044). No significant risk factors for development of airway complication could be identified. Previously described risk factors could not be confirmed. Airway stents were required in 55% of the affected patients. Median survival is impaired by airway complications after lung transplantation. In our cohort, no significant risk factors for the development of airway complications could be identified.

[Interventionnal bronchoscopy for the treatment of tracheobronchomalacia]. / Place de la bronchoscopie interventionnelle dans la prise en charge des trachéobronchomalacies.

Tracheobronchomalacia is usually characterized by more than 50% expiratory narrowing in diameter of the trachea and the bronchi. The expiratory collapse includes two entities: (1) the TBM related to the weakness of the cartilaginous rings, and (2) the Excessive Dynamic Airway Collapse (EDAC) due to the excessive bulging of the posterior membrane. Patients have nonspecific respiratory symptoms like dyspnea and cough. Diagnosis is confirmed by dynamic tests: flexible bronchoscopy and/or computed tomographic scan of the chest. There are different forms of tracheobronchomalacia in adults: primary (genetic, idiopathic) or secondary to trauma, tracheotomy, intubation, surgery, transplantation, emphysema, infection, inflammation, chronic bronchitis, extrinsic compression; or undiagnosed in childhood vascular rings. Some management algorithms have been proposed, but no specific recommendation was established. Only symptomatic patients should be treated. Medical treatments and noninvasive positive pressure ventilation should be the first line therapy, after evaluation of various quality measures (functional status, performance status, dyspnea and quality of life scores). If symptoms persist, therapeutic bronchoscopy permits: (1) patient's selection by stent trial to determine whether patient benefit for surgical airway stabilization; (2) malacic airways stenting in patients who are not surgical candidates, improving QOL despite a high complication rate; (3) the management of stent-related complication (obstruction, plugging, migration granuloma); (4) alternative therapeutics like thermo-ablative solution. Lasty, the development of new types of stents would reduce the complication rates. These different options remained discussed.

Interventional Bronchoscopy in Children: The Way Forward.

Bronchoscopy in children has been utilized primarily to diagnose airway anomalies and obtain bronchoalveolar lavage. Gradual development of thinner bronchoscopes and instruments has opened the gates to the world of bronchoscopic interventions in children. Endobronchial ultrasound guided mediastinal aspiration has been used in adults and children. In younger children, esophageal approach has also been used for sampling of mediastinal lymph nodes. Lung biopsies using cryoprobe have been increasingly used in children. Other bronchoscopic interventions discussed include dilatation of tracheobronchial stenosis, airway stenting, foreign body removal, hemoptysis control, re-expansion of atelectasis etc. Patient safety during the procedure is of paramount importance. Expertise and availability of equipment to handle complications is of huge significance.

Airway Stents from Now to the Future: A Narrative Review.

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.

A single-tube-braided stent for various airway structures.

Background: Airway stent has been widely used in airway procedures. However, the metallic and silicone tubular stents are not customized designed for individual patients and cannot adapt to complicated obstruction structures. Other customized stents could not adapt to complex airway structures with easy and standardized manufacturing methods. Object: This study aimed to design a series of novel stents with different shapes which can adapt to various airway structures, such as the "Y" shape structure at the tracheal carina, and to propose a standardized fabrication method to manufacture these customized stents in the same way. Methods: We proposed a design strategy for the stents with different shapes and introduced a braiding method to prototype six types of single-tube-braided stents. Theoretical model was established to investigate the radial stiffness of the stents and deformation upon compression. We also characterized their mechanical properties by conducting compression tests and water tank tests. Finally, a series of benchtop experiments and ex vivo experiments were conducted to evaluate the functions of the stents. Results: The theoretical model predicted similar results to the experimental results, and the proposed stents could bear a compression force of 5.79N. The results of water tank tests showed the stent was still functioning even if suffering from continuous water pressure at body temperature for a period of 30 days. The phantoms and ex-vivo experiments demonstrated that the proposed stents adapt well to different airway structures. Conclusion: Our study offers a new perspective on the design of customized, adaptive, and easy-to-fabricate stents for airway stents which could meet the requirements of various airway illnesses.

Bronchoscopic interventions for bronchopleural fistulas.

Bronchopleural fistula is a potentially fatal disease most often caused after pneumonectomy. Concomitant problems such as pulmonary infection and respiratory failure are typically the main contributors to patient mortality because of the improper contact between the bronchial and pleural cavity. Therefore, bronchopleural fistulas need immediate treatment, which requires the accurate location and timely closure of the fistula. Currently, bronchoscopic interventions, because of their flexibility and versatility, are reliable alternative therapies in patients for whom surgical intervention is unsuitable. Possible interventions include bronchoscopic placement of blocking agents, atrial septal defect (ASD)/ventricular septal defect (VSD) occluders, airway stents, endobronchial valves (EBVs) and endobronchial Watanabe spigots (EWSs). Recent developments in mesenchymal stem cells (MSCs) transplantation technology and three-dimensional (3D) printed stents have also contributed to the treatment of bronchopleural fistula, but more research is needed to investigate the long-term benefits. This review focuses on the effectiveness of various bronchoscopic measures for the treatment of bronchopleural fistula and the directions for future development.

A Prototype Implantable Artificial Bronchus Reduces Lung Hyperinflation in Recently Deceased Patients with Emphysema.

BACKGROUND: Several minimally invasive treatments have been offered to patients with severe emphysema over the last two decades. Currently, endobronchial valves (EBVs) are the only approved therapeutic option, but this method has drawbacks: only a few can undergo this therapy and the incidence of pneumothorax remains high. A minimally invasive technique, appropriate for a broader patient population and posing fewer risks, would represent a desirable alternative to improve lung function in these patients. OBJECTIVE: The objective of this study was to demonstrate whether a new prototype implantable artificial bronchus (IAB) releases trapped air from the lungs of recently deceased patients with emphysema. METHOD: Seven recently deceased patients with emphysema were mechanically ventilated and the respiratory rate increased from 12 bpm (resting) to 30 bpm (exercise), inducing air trapping and dynamic hyperinflation. This protocol was performed twice, before and after IAB placement. Ventilation parameters and the fraction of inspired oxygen were similar in all patients. Respiratory system plateau pressure (Pplat,rs) and intrinsic positive end-expiratory pressure (iPEEP) were measured. RESULTS: IAB implantation significantly reduced Pplat,rs (p = 0.017) in 6 of 7 deceased patients with emphysema and iPEEP (p = 0.03) in 5 of 7 patients. CONCLUSIONS: Placement of one or two IABs in segmental bronchi (up to 15th generation) proved to be feasible and improved lung function. These findings should provide a basis for subsequent clinical studies to assess the safety and efficacy of IAB in patients with emphysema, as well as identify short- and long-term effects of this innovative procedure.

[Bronchoscopic management of malignant central airway obstructions]. / Traitement endoscopique des obstructions malignes des voies aériennes centrales.

Up to 30% of lung cancer patients suffer from central airway obstruction, resulting in major deterioration in prognosis and quality of life. Interventional bronchoscopy combines a number of invasive techniques used during rigid bronchoscopy. It is designed to rapidly improve symptoms, primarily dyspnea. Applied according to very precise indications, this technique requires careful patient selection and needs to be incorporated into the multimodal oncological management in combination with systemic treatments, radiation therapy and surgery.

Bronchial Remodeling Following Airway Stenting in Pediatric Patients With Tracheobronchial and Congenital Heart Disease.

Background: Treatment of tracheobronchial disease in medically complex infants with congenital heart disease (CHD) is often challenging. When conservative management or surgery fails or is contraindicated, airway stenting can allow for advancement of care or weaning of respiratory support. Methods: We identified 8 cases of airway stenting with balloon-expandable coronary bare-metal stents performed at our institution between February 2019 and September 2022 to relieve conservative treatment-refractory tracheobronchial disease in pediatric patients with CHD. All patients underwent rigid microlaryngoscopy, bronchoscopy, and flexible bronchoscopy as well as computed tomography angiography. Results: Eight patients underwent technically uncomplicated placement of balloon-expandable coronary bare-metal stents in the trachea or bronchus. Immediate improvement in respiratory parameters was noted following stent placement. Six patients were able to wean mechanical ventilation following stent placement, with a median of 2.5 days of mechanical ventilation following the procedure (range, 0-219). All stents were subsequently endoscopically removed at a median of 6.8 months (range, 0.4-16.3 months). In 6 patients, bronchoscopy after stent removal demonstrated a rounder configuration of the airway consistent with bronchial remodeling. Conclusions: In pediatric patients with tracheobronchial and CHD, airway stenting with balloon-expandable bare-metal coronary stents relieved respiratory symptoms with minimal complications and resulted in bronchial remodeling after stent removal.

Use of airway stents to treat malignant tracheobronchial fistulas: Our six-year experience.

Background: This study aims to investigate the indications, safety, complications, and long-term outcomes of airway stenting in the treatment of malignant tracheobronchial fistulas. Methods: The medical records of a total of 34 patients (24 males, 10 females; mean age: 55.4+13 years; range, 23 to 76 years) with malignant tracheobronchial fistulas treated with airway stenting between February 2014 and August 2020 were retrospectively analyzed. Data including demographic features, diagnosis, symptoms, treatment, complications and outcomes were recorded. Results: Thirty-eight airway stents were inserted in 34 patients with malignant tracheobronchial fistulas, including 19 patients with malignant tracheobronchial esophageal fistulas and 15 patients with bronchopleural fistulas. The clinical success and the technical success rates were 91% and 100%, respectively. No perioperative death or severe complications occurred. Chronic complications (>24 h) occurred in eight (23%) patients with malignant tracheobronchial fistula. Median follow-up was 3.5 (range, 1.4 to 5.5) months in patients with malignant tracheobronchial esophageal fistulas and 18 (range, 9.5 to 26.5) months in patients with bronchopleural fistulas. Mortality rates were 79% and 61%, respectively. Conclusion: Airway stent insertion provides a secure and effective treatment for patients with malignant tracheobronchial fistulas.

Comparison of operation time, efficacy and safety between through-the-scope stent and over-the-while stent in malignant central airway obstruction: a multi-center randomized control trial.

Background: Self-expandable metallic (SEM) airway stents are an important approach to treating malignant central airway obstruction (CAO). Standard over-the-while (OTW) stent needs the guidance of a guide-wire. It should be implanted under flouroscopy or the guidance of bronchoscope visualization. In this study, we evaluated the operation time and safety between OTW stent and a novel through-the-scope (TTS) SEM airway stent. Methods: In this multi-center, randomized, parallel-group superiority study, malignant CAO patients were enrolled randomly assigned (2:1) to the TTS stent implantation group (TTS group) or the standard OTW stent group (OTW group) in six sites across China. The entire process of all surgical procedures was recorded by video. Primary endpoint was the operation time of the airway stent implantation and secondary endpoint was the success rate of the stent implantation as well as its efficacy and safety. Results: From May 15, 2017, to December 30, 2018, 148 patients were enrolled from the six sites. We analyzed 134 patients (including 91 patients from the TTS group and 43 patients from the OTW group) according to the per-protocol set. There were no significant differences in the ages, genders, underlying diseases, and stenosis sites between the two groups. The operation time in the TTS group was significantly shorter than that in the OTW group (104±68 vs. 252±111 seconds, P<0.001). Compared to the OTW group, the efficacy of stent implantation (97.80% vs. 90.70%, P=0.093) and rate of first-time successful stent implantation (78.02% vs. 74.42%, P=0.668) were higher in the TTS group, but did not reach statistically significance. The rates of granulation (28.57% vs. 41.86%, P=0.128) and restenosis (15.38% vs. 30.23%, P=0.064) in the TTS group were slightly lower as compared with the OTW group without achieving statistical significance. Conclusions: The TTS stent implantation procedure time was significantly shorter than that of the OTW airway stent with similar efficacy and complications, which might reduce the risk and flexibility of stent implantation. Trial Registration: Chinese Clinical Trial Registry ChiCTR-IOR-17011431.

Changes in Pulmonary Function Test Results and Respiratory Symptoms before and after Airway Stent Removal.

BACKGROUND: Airway stenting is a useful form of palliation for patients with airway stenosis/fistulas; the stent can be removed after addressing the cause of the airway disorder. Patients with airway stents often complain of coughing and difficulty with expectoration, so the use of such stents can negatively affect pulmonary function and worsen symptoms. OBJECTIVES: The aim of this study was to compare pulmonary function and respiratory symptoms before and after stent removal. METHODS: Patients who would later undergo simple airway stent removal were prospectively recruited in two institutions. All stents were removed using both rigid and flexible bronchoscopes with patients under general anesthesia. Pulmonary function tests were performed before stent removal and at 1 and 4 weeks after stent removal. All patients self-reported their respiratory symptoms using a 100-mm visual analog scale (VAS). RESULTS: Of the 31 patients enrolled, 28 (23 with malignant stenoses, 3 with benign stenoses, and 2 with fistulas [21 silicone and 7 metallic stents]) were included in analyses. Pulmonary function measurements before stent removal and at 1 and 4 weeks after stent removal were as follows: vital capacity, 3.00, 3.04, and 3.08 L (p = 0.387); forced expiratory volume in 1 s, 1.96, 1.96, and 2.12 L (p = 0.034); and peak expiratory flow, 3.60, 4.28, and 5.06 L/s, respectively (p < 0.001). Symptoms (cough, sputum production, difficulty with expectoration, and dyspnea) evaluated using the VAS improved significantly after stent removal. No complications were encountered during removal. CONCLUSION: Removal of unnecessary airway stents improves pulmonary function and respiratory symptoms. Any stent that is no longer functioning should be removed.