The When, the How and the Why of Metallic Stent Removal

How risky is it to remove an airway stent?

BACKGROUND

Airway stent removal has traditionally been associated with a high complication rate. Most studies on stent removal are over a decade old, prior to newer anti-cancer therapies, and by including non-contemporary and uncovered metal stents, may not reflect the current practices. We review our experience at Mount Sinai Hospital to report outcomes of stent removal with more contemporary practices.

METHODS

A retrospective review was carried out of all the airway stent removals performed between 2018 to 2022, in adult patients with benign or malignant airway diseases. Stents inserted and removal for stent trials for tracheobronchomalacia were excluded from the final analysis.

RESULTS

Forty-three airway stents removals in 25 patients were included. Twenty-five (58%) stents were removed in 10 patients with benign diseases, and 18 (42%) stents were removed in the remaining 15 patients with malignant diseases. Patients with benign disease were more likely to have their stent removed (OR 3.88). 63% of the stents removed were silicone. The most common reasons for stent removal were migration (n = 14, 31.1%) and treatment response (n = 13, 28.9%). Rigid bronchoscopy was used in 86% of cases. Ninety-eight percent of removals were accomplished in a single procedure. The median time to removal of stents was 32.5 days. Three complications were noted: hemorrhage (n = 1, 2.3%) and stridor (n = 2, 4.6%); one not directly related to the stent removal.

CONCLUSIONS

Covered metal or silicone airway stents, in the era of contemporary stents, better cancer-directed therapies and surveillance bronchoscopies, can be removed safely with the use of rigid bronchoscopy.

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.

Tracheobronchial stent sizing and deployment practices airway stenting practices around the world: a survey study

Background

Tracheobronchial stents types, uses, techniques for deployment and extraction have practice variations around the world.

Methods

We collected responses by sending an online survey of 8 questions to world interventional bronchology member societies and social media groups.

Results

There were 269 respondents from 47 countries. Europe had 97 respondents from 22 countries. There were 8 respondents from Australia, 7 from Africa (3 countries) and 7 from 4 countries in South America (SA). North America (NA) had 72 respondents from 3 countries. Asia had 78 respondents from 14 countries. For stent placements 15% [41] used fiberoptic bronchoscope (FB) only. Rigid bronchoscopy (RB) was solely utilized by 38% [102]. Forty-six percent [123] used a combination of RB and FB (P value <0.00001). For stent extraction 13% [19] used FB alone, 57% [85] used RB, and 36% [54] used a combination of RB and FB (P value <0.00001). Placement of stents were 50.5% [135] only by direct visualization. Twenty-three percent [61] always used fluoroscopic guidance. Twenty-six-point-five percent [71] used fluoroscopy in certain cases (P value <0.00001). Sixty percent [162] decided stent sizing by measurements of stenotic and non-stenotic areas on radiology. Twelve percent [32] respondents used sizing devices. Sixty-five percent [177] used a ruler and bronchoscope to measure stenotic areas. Thirty-eight percent [104] used visual estimation and experience. Seven percent [19] used serial balloon dilatation size. To prevent clogging of stents, 22% [59] prescribed mucolytics. Seventy-three percent [195] nebulized saline, 26% [70] had Mucomyst Nebulization, 24% [65] Nebulized bronchodilators and other methods 11% [30] were advised. Covered self-expandable metal stents (SEMS) 44% was the commonest type of stent used around the world. Silicone stents 37%, Y stents 15%, uncovered SEMS 12%, Montgomery T tube 5% followed. Polyflex stents 3% and custom-made stents 3% were least used. Biodegradable stents were used by 7.5%, and not used by 92.5%.

Conclusions

Tracheobronchial stent practice norms have slowly evolved, but its practice variations lack uniformity, and have sparse evidence-based studies for its direction.

Silicone Stent Versus Fully Covered Metallic Stent in Malignant Central Airway Stenosis

BACKGROUND

Airway stenting to restore airway patency in cases of malignant central airway obstruction is an effective palliation treatment. Our goal was to compare the efficacy after deployment and complications of a fully covered self-expandable metal stent (SEMS) (Aerstent) and a silicone stent (Dumon).

METHODS

This was a retrospective cohort of 2 similar groups of patients with malignant central airway obstruction treated with stents between August 2012 and July 2017. Complications were assessed bronchoscopically. A competing risk for death analysis was performed to adjust the probability of developing a complication.

RESULTS

Seventy patients (29 with silicone stents and 41 with SEMS) were included. Stent insertion was successful in all cases. Mucus retention was the most frequent complication (75.9% with silicone stents and 84.8% with SEMS; P = .51), followed by granulation tissue (51.7% with silicone stents and 41.3% with SEMS; P = .52) and migration (6.9% with silicone stents and 13.0% with SEMS; P = .47). In the first month, the cumulative incidence of a complication was 36.7% for silicone stents and 41.3% for SEMS and increased to 90.0% and 97.8% after 6 months, respectively (hazard ratio = 1.66; P = .04). A competing risk for death analysis showed an adjusted hazard ratio of 1.41 (P = .49) indicating no differences in overall complications between stents.

CONCLUSIONS

Both stents were equally successful and safe. The incidence of complications increased over time to 90% at 6 months for both stents. The risk of overall complications was higher for SEMS; nevertheless, when mortality was measured in a competitive risk analysis, no differences were found between SEMS and silicone stents.

Endobronchial removal of uncovered stent using argon plasma coagulation via fibreoptic bronchoscopy

Bronchial stenosis is a complication of lung transplantation that often requires repeated balloon dilation, endobronchial treatments, and possibly stent placement. Endobronchial stents, particularly uncovered ones, may have several complications including excessive granulation tissue that cause airways obstruction and impaired mucociliary clearance, which may lead to inflammation and infections. Removal of epithelized endobronchial stents is usually done in the operating room using rigid bronchoscopy. Argon plasma coagulation (APC) has been used for removal of biliary stents. One case report described an endotracheal uncovered stent removal using this technique. APC can be used via flexible bronchoscopy, which may carry less risk of complications and can be done in an outpatient setting. In this case, we report using APC, at a low energy level, for complete removal of a totally epithelialized endobronchial uncovered stent in a patient experiencing stent-related complications.