Non-malignant central airway obstruction

Predictors in the treatment of malignant central airway obstruction with silicone stents

PURPOSE

To examine the role of the silicone stent in palliation of malignant central airway obstruction and identify potential preprocedural predictors for postprocedural outcome.

METHODS

Patients treated with endoscopic insertion of tracheobronchial silicone stents for malignant central airway obstruction at Aarhus University Hospital from 2012 to 2022 were identified from electronic medical records. Statistical analyses were carried out to identify factors affecting Days Alive and Out of Hospital, complications and overall survival.

RESULTS

81 patients underwent a total of 90 tracheobronchial stent insertions. Days Alive and Out of Hospital (DAOH) for the first 30 days were affected negatively by urgent intervention, p < 0.001, preprocedural non-invasive respiratory support, p < 0.001, and preprocedural intubation, p = 0.02. Post-procedural oncological treatment was associated with a significant improved DAOH, p = 0.04. Symptomatology and lesion characteristics were not significantly associated with any impact on DAOH. Overall survival was poor (mean survival was 158 days), and only significantly affected by severe degree of dyspnea, p = 0.02, and postprocedural oncological treatment, p < 0.001. Complication where registered in 25.6% of cases within the first 30 days was observed. Procedure-related mortality was 3.7%. Based on chart annotations by an ENT-surgeon, 95% of the patients experienced relief of symptoms following stent insertion.

CONCLUSIONS

Palliative tracheobronchial airway stenting with silicone stents is found to have a beneficial impact, more research is required for identification of predictors for postprocedural outcome based on preprocedural classifications.

Comprehensive use of a high-frequency electric knife, balloon dilatation, and cryotherapy for tuberculous central tracheobronchial cicatricial constriction

BACKGROUND

To examine the benefits of interventional therapy for cicatricial constriction using a high-frequency electric knife, saccular dilatation, and cryotherapy.

METHODS

This case series included patients with central tracheobronchial cicatricial constriction admitted to the Department of Tuberculosis of Henan Provincial Chest Hospital from July 2018 to March 2021 and treated with bronchoscopic interventional therapies based on systemic anti-tuberculosis treatment.

RESULTS

96 patients were included, in whom 443 interventional therapies were performed. The total mid-(3 months) and long-term (12 months) effective rates were both 100%. The internal diameter of tracheobronchial stenosis increased after the operation, and the difference was statistically significant (all < 0.05). After interventional treatment, patients' symptoms of choking sensation in the chest and shortness of breath were relieved. Respiratory function was obviously improved. The ratios of hemorrhage, granulation hyperplasia, chest pain, and postoperative fever were 58.2%, 42.6%, 31.3%, and 26.7%, respectively. No focal transmission and progression of tuberculosis occurred, and no serious complications were observed.

CONCLUSION

The use of a high-frequency electric knife, saccular dilatation, and/or cryotherapy according to the pathological stage of the tracheobronchial cicatricial constriction is feasible, with good mid- and long-term curative effects and few complications.

Complications of an uncovered metallic tracheal stent managed by veno-venous extracorporeal membrane oxygenation: a case report

Airway stents are primarily inserted for the management of airway obstruction associated with an inoperable malignancy and are rarely indicated in benign disease. We outline the complications associated with tracheal stents and describe the use of veno-venous extracorporeal membrane oxygenation (V-V ECMO) to facilitate open tracheal surgery in an apnoeic patient who had an uncovered metallic tracheal stent left in place for an inappropriately long period. Computerised tomography imaging of the neck and thorax provided information for operative planning and described of the stent in addition to the extensive granulation tissue at the distal end of the stent. Veno-venous extracorporeal membrane oxygenation was used to facilitate open tracheal surgery, removal of the tracheal stent and formation of a surgical tracheostomy. Prolonged use of an uncovered metallic airway stent in younger patients with benign disease may lead to the stent being difficult to remove. There may be an accumulation of granulation tissue with the risk of airway obstruction.

Managing complications of percutaneous tracheostomy and gastrostomy

Percutaneous tracheostomy and gastrostomy are some of the most commonly performed procedures at bedside in the intensive care unit. While they are generally considered safe, they can be associated with numerous short and long-term complications, many of which can occur long after their placement and cause significant morbidity. Performers of these procedures should possess a comprehensive understanding of procedural indications and contraindications, and know how to recognize and manage complications that may arise. In this review, we highlight complications of percutaneous tracheostomy and describe strategies for their prevention and management, with a special focus on post-tracheostomy tracheal stenosis. Other complications reviewed include bleeding, pneumothorax and subcutaneous emphysema, posterior wall injury, tube displacement, tracheomalacia, tracheoinominate artery fistula, tracheo-esophageal fistula, and stomal cellulitis. Gastrostomy complications and their management are also discussed including bleeding, internal organ injury, necrotizing fasciitis, aspiration pneumonia, buried bumper syndrome, tumor seeding, wound infection, tube displacement, peristomal leakage, and gastric outlet obstruction. In light of the potentially serious outcomes associated with complications of percutaneous tracheostomy and gastrostomy, the emphasis should be placed on risk-reduction strategies to minimize morbidity and mortality. We therefore present detailed pragmatic and comprehensive checklists to serve as a reference for clinicians involved in performing these procedures.

Protective effects of different anti‑inflammatory drugs on tracheal stenosis following injury and potential mechanisms

Tracheal stenosis following injury cannot be effectively treated. The current study compared the protective effects of different anti-inflammatory drugs on tracheal stenosis and investigated their possible mechanisms. Rabbit tracheal stenosis models following injury were constructed and confirmed using hematoxylin and eosin (H&E) staining. A total of 30 rabbits were divided into the control (CON), penicillin (PEN), erythromycin (ERY), budesonide (BUD) and PEN + ERY + BUD groups (n=6). Stenotic tracheal tissue, serum and bronchoalveolar lavage fluid (BALF) were collected 10 days after continuous treatment. Pathological changes in the tracheas were observed by H&E staining. Histone deacetylase 2 (HDAC2) expression in tracheal tissues was detected by immunofluorescence. Immunohistochemistry was performed to detect collagen I (Col-I) and collagen III (Col-III) levels in tracheal tissues. Transforming growth factor β1 (TGF-β1), vascular endothelial growth factor (VEGF) and interleukin 8 (IL-8) levels in serum and BALF samples were determined using ELISA kits. Western blotting detected HDAC2, IL-8, TGF-β1 and VEGF levels in tracheal tissues. H&E staining demonstrated that tracheal epithelial hyperplasia and fibroblast proliferation in the ERY and PEN + ERY + BUD groups markedly improved compared with the CON group. Furthermore, in tracheal tissues, HDAC2 expression was significantly increased and IL-8, TGF-β1, VEGF, Col-I and Col-III levels were significantly decreased in the ERY and PEN + ERY + BUD groups compared with the CON group. Additionally, the results for the PEN + ERY + BUD were more significant compared with the ERY group. In serum and BALF samples, IL-8, TGF-β1 and VEGF levels in the ERY and PEN + ERY + BUD groups were significantly lower compared with the CON group, with the results of the PEN + ERY + BUD group being more significant compared with the ERY group. There were no significant differences between the PEN, BUD and CON groups. ERY inhibited tracheal granulation tissue proliferation and improved tracheal stenosis following injury and synergistic effects with PEN and BUD further enhanced these protective effects. The mechanism may involve HDAC2 upregulation and inhibition of local airway and systemic inflammatory responses.

β-elemene alleviates airway stenosis via the ILK/Akt pathway modulated by MIR143HG sponging miR-1275

Background

We have previously found that β-elemene could inhibit the viability of airway granulation fibroblasts and prevent airway hyperplastic stenosis. This study aimed to elucidate the underlying mechanism and protective efficacy of β-elemene in vitro and in vivo.

Methods

Microarray and bioinformatic analysis were used to identify altered pathways related to cell viability in a β-elemene-treated primary cell model and to construct a β-elemene-altered ceRNA network modulating the target pathway. Loss of function and gain of function approaches were performed to examine the role of the ceRNA axis in β-elemene's regulation of the target pathway and cell viability. Additionally, in a β-elemene-treated rabbit model of airway stenosis, endoscopic and histological examinations were used to evaluate its therapeutic efficacy and further verify its mechanism of action.

Results

The hyperactive ILK/Akt pathway and dysregulated LncRNA-MIR143HG, which acted as a miR-1275 ceRNA to modulate ILK expression, were suppressed in β-elemene-treated airway granulation fibroblasts; β-elemene suppressed the ILK/Akt pathway via the MIR143HG/miR-1275/ILK axis. Additionally, the cell cycle and apoptotic phenotypes of granulation fibroblasts were altered, consistent with ILK/Akt pathway activity. In vivo application of β-elemene attenuated airway granulation hyperplasia and alleviated scar stricture, and histological detections suggested that β-elemene's effects on the MIR143HG/miR-1275/ILK axis and ILK/Akt pathway were in line with in vitro findings.

Conclusions

MIR143HG and ILK may act as ceRNA to sponge miR-1275. The MIR143HG/miR-1275/ILK axis mediates β-elemene-induced cell cycle arrest and apoptosis of airway granulation fibroblasts by modulating the ILK/Akt pathway, thereby inhibiting airway granulation proliferation and ultimately alleviating airway stenosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-021-00261-0.

Long-term prognostic factors of clinical success after interventional bronchoscopy in patients with scarring central airway stenosis

Background

Scarring central airway stenosis (SCAS) is a potentially life-threatening condition with debilitating symptoms. Interventional bronchoscopy is increasingly used to relieve symptoms in patients with SCAS, but recurrent stenosis is frequently observed. Little data exist on the long-term prognosis of interventional bronchoscopy for SCAS. We aimed to assess the prognostic factors of bronchoscopic interventions in patients with SCAS to optimize treatment.

Methods

This was a retrospective study that enrolled 119 consecutive patients with SCAS from January 2010 to April 2019 at our institution. Long-term clinical success was defined as airway stenosis < 50%, no limitation of physical activity, and a stable condition for > 12 months after the last interventional procedure. We compared patients’ demographics, airway stenosis characteristics, and interventional procedures between the successful and unsuccessful groups, and identified significant predictors of long-term outcome with univariate and multivariate logistic regression.

Results

A total of 119 patients with 577 therapeutic bronchoscopies were included. Seventy-five (63%) patients were considered to have long-term clinical success. Older age, male gender, smoking, elevated C-reactive protein level, subglottic stenosis, stent or T-tube implantation, previous interventional treatment, and multiple procedures per year were potentially associated with unsuccessful long-term outcomes in the univariate analysis. Current smoker status (odds ratio [OR] 5.70, 95% confidence interval [CI] 1.35–24.17, P = 0.018), subglottic stenosis (OR 4.35, 95% CI 1.31–14.46, P = 0.017), and stent implantation (OR 4.96, 95% CI 1.33–18.48, P = 0.017) were associated with decreased odds of long-term success in the multivariate logistic regression analysis. Of note, there was no significant difference in odds of success between former smokers and nonsmokers.

Conclusions

Current smoker status, subglottic stenosis, and stent implantation are independent factors associated with reduced long-term efficacy of interventional bronchoscopy for SCAS. Smoking cessation should be encouraged to improve the outcome of therapeutic bronchoscopy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01434-5.

Feasibility analysis of flexible bronchoscopy in conjunction with noninvasive ventilation for therapy of hypoxemic patients with Central Airway Obstruction: a retrospective study

BACKGROUND

Interventional bronchoscopy for hypoxemic patients with central airway obstruction (CAO) is typically performed under general anesthesia. This approach poses remarkable challenge for both bronchoscopist and anesthesiologist. Noninvasive ventilation (NIV) during flexible bronchoscopy (FB) has been successfully used in hypoxemic patients, but rarely in the treatment of hypoxemic patients with CAO.

OBJECTIVE

To evaluate the feasibility of therapeutic FB assisted with NIV for therapy of hypoxemic patients with CAO.

METHOD

Twenty-nine hypoxemic CAO patients treated with FB from December 2010 to May 2016 in our hospital were retrospectively reviewed, either aided with NIV under sedation (NIV group ) or through artificial airway under general anesthesia (control group). Interventional procedures included balloon dilation, electrocautery and argon plasma coagulation.

RESULT

Fifteen patients were enrolled in the NIV group and 14 in the control group. The success rate (93.3% VS 92.9%, p = 1.0), procedure time (60.5 ± 4.2 min VS 67.8 ± 5.6 min, p = 0.31) and oxygenation improvement between the two groups have no significant difference. Less reduction of systolic blood pressure and heart rate during procedure was observed in the NIV group. The NIV group showed shorter admission time before procedure than the control group (35.1 ± 4.6 h VS 55.6 ± 5.6 h, p < 0.01). In addition, procedure fee in the NIV group was significantly less than that in the control group (540.7 ± 62.8$ VS975.4 ± 69.5$, p < 0.0001).

CONCLUSION

FB assisted with NIV is a safe, efficient and economic method for therapy of selected hypoxemic patients with CAO.

Bronchoscopic cryosurgery for metastatic tumor causing central airway obstruction: A case report

RATIONALE

Bronchoscopic cryotherapy has been considered as one of the optional interventions for unresectable malignant central airway obstruction (CAO). And it provides high safety and effectiveness in airway patency re-establishment. This report describes the interventional bronchoscopic cryotherapy for a patient with CAO caused by squamous cell carcinoma of the esophagus. We display a series of dramatic change of chest radiographs before and after the intervention.

PATIENT CONCERNS

A 70-year-old man with squamous cell carcinoma of the middle third of the esophagus (initial staging, pT2N0M0; stage IIB; in January 2017) underwent Video-assisted esophagectomy and reconstruction with a gastric conduit via a substernal route. Following Chest computed tomography and positron emission tomography revealed disease progression with paratracheal metastases. Progressive dyspnea and chest pain lasted for a month, and he was admitted to the ER.

DIAGNOSES

Blood gas analysis revealed type I respiratory failure (pH, 7.445; PaO2, 69.4 mmHg; PaCO2, 40.6 mmHg). Other laboratory data were grossly normal. Chest radiography revealed a total left lung collapse. Chest CT identified a tumor blocking the left mainstem bronchus with the consolidation of the left lung.

INTERVENTIONS

Dexamethasone and epinephrine inhalation were administered for initial symptom relief. Bronchoscopy performed 4 days after admission revealed a huge tumor completely occluding the left mainstem bronchus orifice. The occlusion was completely resolved following cryotherapy. Then, the first course of palliative chemotherapy with cisplatin plus fluorouracil, followed by the second course a month later, was administered.

OUTCOMES

The latest chest radiograph showed a patent airway. The patient's condition remained stable for at least the following 2 months.

LESSONS

Malignant CAO is a rare but potentially life-threatening condition. Several acceptable bronchoscopy techniques exist for treatment. Cryotherapy has high safety and effectiveness in airway patency re-establishment.

Appropriate treatment sessions of flexible bronchoscopic balloon dilation for patients with nonmalignant central airway stenosis

BACKGROUND

Balloon dilation is a primary treatment for nonmalignant tracheobronchial stenosis, but often requires multiple treatment sessions to maintain therapeutic efficacy. No guideline is available to suggest the appropriate maximum number of treatment sessions. This study aimed to investigate the relationship between the number of balloon dilation sessions and its long-term therapeutic effectiveness in Chinese patients with nonmalignant central airway stenosis.

METHODS

A total of 111 patients with nonmalignant central airway stenosis treated with flexible bronchoscopic balloon dilation from January 2005 to September 2012 were included. The cumulative long-term effective rate was compared between any two adjacent sessions of balloon dilation treatment by McNemar's test. Multivariate Cox regression was performed to investigate the independent factors associated with long-term effectiveness.

RESULTS

The cumulative long-term effective rate was significantly increased between any two adjacent sessions before the 6th session of treatment (all p < 0.05) but was no longer significantly increased after the 6th session. The stenosis diameter was larger in the patients receiving ⩽6 treatment sessions than those receiving ⩾6 treatment sessions. Multivariate Cox regression showed that the treatment session was an independent factor associated with long-term effectiveness (hazard ratio = 0.65, 95% confidence interval: 0.57-0.76, p < 0.001).

CONCLUSION

These results suggest that the maximum number of treatment sessions of balloon dilation may be six, and patients requiring more treatment sessions were more likely to have delayed long-term effectiveness.

β-Elemene inhibits the proliferation of primary human airway granulation fibroblasts by down-regulating canonical Wnt/β-catenin pathway

Benign airway stenosis is a clinical challenge because of recurrent granulation tissues. Our previous study proved that a Chinese drug, β-elemene, could effectively inhibit the growth of fibroblasts cultured from hyperplastic human airway granulation tissues, which could slow down the progression of this disease. The purpose of the present study is to find out the mechanism for this effect. We cultured fibroblasts from normal human airway tissues and human airway granulation tissues. These cells were cultured with 160 μg/ml normal saline (NS), different doses of β-elemene, or 10 ng/ml canonical Wnt/β-catenin pathway inhibitor (Dickkopf-1, DKK-1). The proliferation rate of cells and the expression of six molecules involved in canonical Wnt/β-catenin pathway, Wnt3a, glycogen synthase kinase-3β (GSK-3β), β-catenin, α-smooth muscle actin (α-SMA), transforming growth factor-β (TGF-β), and Collagen I (Col-I), were measured. At last, we used canonical Wnt/β-catenin pathway activator (LiCl) to further ascertain the mechanism of β-elemene. Canonical Wnt/β-catenin pathway is activated in human airway granulation fibroblasts. β-Elemene didn't affect normal human airway fibroblasts; however, it had a dose-responsive inhibitive effect on the proliferation and expression of Wnt3a, non-active GSK-3β, β-catenin, α-SMA, TGF-β, and Col-I of human airway granulation fibroblasts. More importantly, it had the same effect on the expression and nuclear translocation of active β-catenin. All these effects were similar to 10 ng/ml DKK-1 and could be attenuated by 10 mM LiCl. Thus, β-elemene inhibits the proliferation of primary human airway granulation fibroblasts by down-regulating canonical Wnt/β-catenin pathway. This pathway is possibly a promising target to treat benign tracheobronchial stenosis.

Airway stents

Stents and tubes to maintain the patency of the airways are commonly used for malignant obstruction and are occasionally employed in benign disease. Malignant airway obstruction usually results from direct involvement of bronchogenic carcinoma, or by extension of carcinomas occurring in the esophagus or the thyroid. External compression from lymph nodes or metastatic disease from other organs can also cause central airway obstruction. Most malignant airway lesions are surgically inoperable due to advanced disease stage and require multimodality palliation, including stent placement. As with any other medical device, stents have significantly evolved over the last 50 years and deserve an in-depth understanding of their true capabilities and complications. Not every silicone stent is created equal and the same holds for metallic stents. Herein, we present an overview of the topic as well as some of the more practical and controversial issues surrounding airway stents. We also try to dispel the myths surrounding stent removal and their supposed use only in central airways. At the end, we come to the long-held conclusion that stents should not be used as first line treatment of choice, but after ruling out the possibility of curative surgical resection or repair.

Awareness, Competencies, and Practice Patterns in Tracheobronchomalacia: A Survey of Pulmonologists

BACKGROUND

Tracheobronchomalacia (TBM) is a disorder of expiratory central airway collapse. TBM is separate from excessive dynamic airway collapse. Historically TBM has lacked a universally accepted definition. No consensus recommendations on evaluation and management exist. We suspect these unresolved issues contribute to deficits in pulmonologists' awareness and management of TBM.

METHODS

We created a 20-question survey obtaining information about overall awareness, knowledge base, competencies, and practice patterns in managing TBM. The survey was disseminated via email by American College of Chest Physicians to members of their Interventional Chest Diagnostic Procedures Network.

RESULTS

One hundred sixty-five clinicians participated in the survey. Seventy-seven percent of respondents chose the correct definition for TBM. Twenty-two percent of respondents never considered TBM in patients with cough, sputum production, dyspnea, and recurrent infections. Thirty-eight percent did not proceed with further evaluation of TBM if pulmonary function tests were normal. Eighteen percent use a classification system to describe the severity of TBM. Only 29% could identify TBM on bronchoscopy and only 39% identified TBM on computed tomography. Respondents that practice interventional pulmonology demonstrated a better knowledge base of TBM.

CONCLUSION

This survey exposes deficits among pulmonologists in their ability to confidently and correctly diagnose and manage TBM. These deficits are not surprising as our understanding of this clinical entity is evolving. There exists a need for further education of pulmonologists about TBM and a need to promote collaborative efforts through research and expert consensus committees to progress our knowledge and management of this disease.

The anesthesia of trachea and bronchus surgery

The trachea and bronchus surgery is generally performed due to stenosis, traumatic injury, foreign body and tumors. Preoperative evaluation and anesthesia management are very important issues because of higher mortality and morbidity rates. Patients may be asymptomatic, but airway difficulties, hypoxia, stridor, cough, hemoptysis are common conditions in these patient population. The collaboration between the surgeon and the anesthesiologist is very substantial and necessary. Anesthetic techniques include various applications such as one lung ventilation, fiberoptic intubation, jet ventilation, and apneic oxygenation, general anesthesia with or without neuromuscular blockade. In this review, anesthesia management of the trachea and bronchus surgery is evaluated in the light of new knowledge.

Balloon Dilatation of a Case of Tuberculous Tracheobronchial Stenoses during the Course of Antituberculous Treatment

We report a case of posttuberculosis (TB) tracheobronchial stenoses presented with progressive exertional dyspnea during the course of anti-TB treatment. An 83-year-old Japanese man was admitted for progressive dyspnea; chest X-ray and CT showed stenosis of distal trachea and left main bronchus. Pulmonary function test revealed reduction of FEV1. Balloon dilatation without stent insertion was the choice for this patient for multiple reasons with marked improvement of symptoms.