Medium-Term Follow-Up After Deployment of Ultraflex Expandable Metallic Stents to Manage Endobronchial Pathology

Fluoroscopic removal of self-expandable metallic airway stent in patients with airway stenosis

To study the safety and efficacy of fluoroscopic removal of self-expandable metallic stent for airway stenosis.We conducted a retrospective analysis of 67 consecutive patients, 39 male and 28 female, who underwent fluoroscopic stent removal from March 2011 to April 2017. The patients ranged in age from 12 to 85 years. Seventy-six airway stents were implanted, 70 covered stents and 6 bare stents, including 9 stents for second stent implantation after removal. All patients underwent chest computed tomography scans with/without bronchoscopy before stent removal. The indication of stent removal and postinterventional complications were analyzed retrospectively.Seventy-four of 76 airway stents were successfully removed, only 2 stent showed retained struts after removal, for a technical success rate of 97.4%. Two patients died of complications (1 hemorrhage and 1 respiratory failure), resulting in a clinical success rate of 94.7%. Five stents showed strut fracture and the remaining 71 stents were removed in 1 piece. Indications for stent removal include planned removal (n = 40), excessive granulation tissue (n = 15), intolerance of stenting (n = 6), inadequate expansion and deformation (n = 5), stent migration (n = 5), replacement of bare stent (n = 4), and strut fracture (n = 1). There were 17 complications of stent removal: death from massive bleeding (n = 1), restenosis requires stenting (n = 9), strut fracture or residue (n = 5), dyspnea requires mechanical ventilation (n = 2). The survival rates were 83.8%, 82.1%, and 82.1% for 0.5, 3, and 6 years.Fluoroscopic removal of airway stent is technically feasible and effective. Stents are recommended for removal within 3 months for treating airway stenosis.

Metallic stent insertion and removal for post-tracheotomy and post-intubation tracheal stenosis

PURPOSE

To study the safety and effectiveness of fluoroscopic insertion and removal of self-expandable metallic airway stent for post-tracheotomy tracheal stenosis (PTTS) and post-intubation tracheal stenosis (PITS).

METHODS

We conducted a retrospective analysis of 32 patients who underwent fluoroscopic stenting from September 2011 to March 2017. The patients ranged in age from 12 to 69 years. Thirty-eight airway stents were implanted, 35 covered stents and three bare stents. Nineteen airway stents were used for 16 cases of PITS or PTTS. All patients underwent chest CT scans with/without bronchoscopy prior to stent removal. The indication of stent removal and post-interventional complications were analyzed.

RESULTS

All 38 airway stents were successfully inserted. Insufficient expansion and tissue hyperplasia were most common complications after stenting. Thirty five of 38 airway stents were successfully removed fluoroscopically, with a technical success rate of 92.1%. Routine removal was performed after 2.9 ± 0.3 months, and stent restenosis was found after a mean duration of 2.7 ± 0.3 months. There were six complications of stent removal with no death. Four stents showed strut fracture after removal, of which three stent pieces retained. Two patients showed dyspnea immediately after removal and required mechanical ventilation in PTTS. One patient with PTTS lost of follow-up during a mean period of 33.7 ± 3.9 months. The one-, three- and five-year patency rates were 87.1%, 76.2% and 70.8%, respectively. There was no significant difference between PITS and PTTS.

CONCLUSIONS

Fluoroscopic insertion and removal of airway stent is safe and effective for PITS and PTTS. A three-month retention time is reasonable for airway stents.

Emergency cricothyroidotomy following tracheobronchial stenting

A man aged 51 years was referred for tracheobronchial stenting after a poorly differentiated oesophageal carcinoma had progressed to cause stridor. Bronchoscopy revealed a left vocal cord palsy and tumour infiltration into the trachea. A tracheobronchial stent was placed, and after distal migration was endoscopically resited. Returning from theatre, the patient developed severe upper airway obstruction that progressed to cause CO₂ narcosis and loss of consciousness. A rapid sequence induction was initiated, and a Glidescope revealed bilateral vocal cord palsy with severe oedema causing an inability to pass a tube or stylet. Tracheostomy was attempted above the suprasternal notch but was obstructed by the stent. Oxygen saturations dropped steadily, reaching as low as 38%. Emergency cricothyroidotomy was performed, compliant with DAS guidelines, that proved successful. The stent was removed, which was blocked with blood and secretions, and tracheostomy was placed 2 days later. The patient made a full neurological recovery.

COMPARISON OF FLUOROSCOPY AND COMPUTED TOMOGRAPHY FOR TRACHEAL LUMEN DIAMETER MEASUREMENT AND DETERMINATION OF INTRALUMINAL STENT SIZE IN HEALTHY DOGS

Tracheal collapse is a progressive airway disease that can ultimately result in complete airway obstruction. Intraluminal tracheal stents are a minimally invasive and viable treatment for tracheal collapse once the disease becomes refractory to medical management. Intraluminal stent size is chosen based on the maximum measured tracheal diameter during maximum inflation. The purpose of this prospective, cross-sectional study was to compare tracheal lumen diameter measurements and subsequent selected stent size using both fluoroscopy and CT and to evaluate inter- and intraobserver variability of the measurements. Seventeen healthy Beagles were anesthetized and imaged with fluoroscopy and CT with positive pressure ventilation to 20 cm H2 O. Fluoroscopic and CT maximum tracheal diameters were measured by three readers. Three individual measurements were made at eight predetermined tracheal sites for dorsoventral (height) and laterolateral (width) dimensions. Tracheal diameters and stent sizes (based on the maximum tracheal diameter + 10%) were analyzed using a linear mixed model. CT tracheal lumen diameters were larger compared to fluoroscopy at all locations (P-value < 0.0001). When comparing modalities, fluoroscopic and CT stent sizes were statistically different. Greater overall variation in tracheal diameter measurement (height or width) existed for fluoroscopy compared to CT, both within and among observers. The greater tracheal diameter measured with CT and lower measurement variability has clinical significance, as this may be the imaging modality of choice for appropriate stent selection to minimize complications in veterinary patients.

Indications and interventional options for non-resectable tracheal stenosis

Non-specific presentation and normal examination findings in early disease often result in tracheal obstruction being overlooked as a diagnosis until patients present acutely. Once diagnosed, surgical options should be considered, but often patient co-morbidity necessitates other interventional options. Non-resectable tracheal stenosis can be successfully managed by interventional bronchoscopy, with therapeutic options including airway dilatation, local tissue destruction and airway stenting. There are common aspects to the management of tracheal obstruction, tracheomalacia and tracheal fistulae. This paper reviews the pathogenesis, presentation, investigation and management of tracheal disease, with a focus on tracheal obstruction and the role of endotracheal intervention in management.

Computed tomography measurements for airway stent insertion in malignant airway obstruction

BACKGROUND

Metallic airway stents for malignant airway obstruction are considered safe, yet are not without complications. This study reviews the role of computed tomography (CT) airway measurements for planning stent placement in malignant airway obstruction before the actual therapeutic procedure to avoid invasive diagnostic evaluation before the stent placement and to reduce complications.

METHODS

This study is a retrospective review of information from a stent order database and medical records of patients receiving stents for malignant airway obstruction at a university hospital over a 12-year period. CT scans were used to determine stent diameter by calculating mean diameters of healthy adjacent zones (proximal and distal), stent length (length of diseased airway), and location and number of potential stents. Results of CT planning before bronchoscopy were judged by complication rates.

RESULTS

Patient population consisted of 69 patients, 61.7±14.0 years old, 40 males, in whom 92 stents were inserted. The most frequent cause of airway obstructions was tracheobronchial cancer (32). All patients had nitinol stent placement; 66 stents were covered and 26 were uncovered. Follow-up time was 1 to 1067 days (median: 35 days). Complication rate was 10.1% and mainly involved the patients with tracheal obstruction (6). Complications included stent fractures (2), migration (2), granuloma (1), and infectious tracheitis (2). One early death within 24 hours after the procedure was not related to stent placement. Five patients required follow-up therapeutic bronchoscopy to treat the complications.

CONCLUSIONS

These results suggest that prestent planning by noninvasive method of obtaining CT scan provides optimal stent size and position, possibly avoiding a diagnostic bronchoscopy and reducing complications. Further prospective study is needed to confirm these results because of limitation of this study's design.

Tracheal stricture and fistula: management with a barbed silicone-covered retrievable expandable nitinol stent

OBJECTIVE

The purpose of this study was to evaluate the safety and effectiveness of a barbed silicone-covered retrievable expandable nitinol stent in preventing stent migration in patients with tracheal strictures or fistulas.

SUBJECTS AND METHODS

Under fluoroscopic guidance, barbed silicone-covered retrievable expandable nitinol stents were placed in 15 patients with tracheal strictures, two patients with fistulas, two patients with combined strictures and fistulas, and one patient with variable extrathoracic airway obstruction. The three pairs of barbs were attached to the external stent surface at the middle of the stent at equal intervals. Technical success, improvement in respiratory status, complications, and related interventions were evaluated.

RESULTS

The technical success rate was 100%, and respiratory status improved or the fistula closed in all 20 patients. Complications included sputum retention (three patients), tumor overgrowth (three patients), pain (one patient), and granulation tissue formation (one patient). No stent migration occurred, even in the three patients without fixed strictures. Four stents subsequently were removed because of complications, and one stent was removed because the patient's condition improved. Stent removal was not difficult and was uneventful. The silicone membranes and barbs of the removed stents were intact.

CONCLUSION

Use of a barbed silicone-covered retrievable expandable nitinol stent relieves dyspnea and facilitates fistula closure in patients with benign or malignant tracheal strictures or fistulas. The barbed design of the stent is important in preventing migration.

Results of combined photodynamic therapy (PDT) and high dose rate brachytherapy (HDR) in treatment of obstructive endobronchial non-small cell lung cancer (NSCLC)

INTRODUCTION

We reviewed the outcome of combined photodynamic therapy (PDT) and high dose rate brachytherapy (HDR) for patients with symptomatic obstruction from endobronchial non-small cell lung cancer.

METHODS

Nine patients who received combined PDT and HDR for endobronchial cancers were identified and their charts reviewed. The patients were eight males and one female aged 52-73 at diagnosis, initially presenting with various stages of disease: stage IA (N=1), stage IIA (N=1), stage III (N=6), and stage IV (N=1). Intervention was with HDR (500 cGy to 5 mm once weekly for 3 weeks) and PDT (2 mg/kg Photofrin, followed by 200 J/cm(2) illumination 48 h post-infusion). Treatment group 1 (TG-1, N=7) received HDR first; Treatment group 2 (TG-2, N=2) received PDT first. Patients were followed by regular bronchoscopies.

RESULTS

Treatments were well tolerated, all patients completed therapy, and none were lost to follow-up. In TG-1, local tumor control was achieved in six of seven patients for: 3 months (until death), 15 months, 2+ years (until death), 2+ years (ongoing), and 5+ years (ongoing, N=2). In TG-2, local control was achieved in only one patient, for 84 days. Morbidities included: soft-tissue contraction and/or other reversible benign local tissue reactions (N=8) and photosensitivity reactions (N=2).

CONCLUSIONS

Combined HDR/PDT treatment for endobronchial tumors is well tolerated and can achieve prolonged local control with acceptable morbidity when PDT follows HDR and when the spacing between treatments is 1 month or less. This treatment regimen should be studied in a larger patient population.

Airway stents in children

Airway obstruction in children is a rare, but difficult clinical problem, with no clear agreement on optimal therapeutic approach. Stenting of the airway has been used successfully in adults, and is an attractive alternative in children. Fundamental differences of pediatric compared to adult use include the benign nature of most stenoses, the narrow and soft airways of children, the required long-term tolerance and adaptation to growth. These differences may significantly alter the therapeutic balance, calling into question the precise role stents play in the treatment of airway obstruction in children. Stent placement can be technically demanding but is not exceedingly difficult. Experience is necessary to select the proper size and type of stent. Metal stents usually achieve airway patency and clinical improvement in the majority of cases, while this is less frequently the case with silicone stents. Some complications such as granulation and secretion retention seem to occur in most children after stent implantation. Unfortunately, severe complications including death have been reported in a significant proportion of children. Stent related mortality can be estimated at 12.9% from published data, but these include complication centered reports. The initial euphoria for airway stents in children has largely abated and most authors agree that they should only be employed in circumstances with no good alternatives. It is crucial that all surgical and medical alternatives are considered and the decision to place a stent is not made because other options are overlooked or not available locally. Stent use in a palliative setting has also been reported and is probably reasonable. Stents will only allow limited adaptation for the growth of pediatric airways by balloon dilatation. All metal stents should be considered as potentially permanent, and removal sometimes may only be possible through a surgical and sometimes risky approach.

A novel approach to the management of acute tracheal tear

OBJECTIVE

We describe the emergency use of a covered, expandable, removable tracheal stent in a patient who developed a large posterior tracheal tear complicating endobronchial therapy for large airway obstruction.

METHOD

Case report and review of the literature concerning management of acute tracheal tear.

RESULTS AND CONCLUSION

Our patient demonstrates that endotracheal stenting is an option for managing acute large airway tear. Moreover, the use of a removable stent allows not only for rapid closure of the defect but also removal once the defect has healed, thus avoiding long-term complications of stent deployment.

Palliative care in lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition)

GOALS/OBJECTIVES: To review the scientific evidence on symptoms and specific complications that are associated with lung cancer, and the methods available to palliate those symptoms and complications.

METHODS

MEDLINE literature review (through March 2006) for all studies published in the English language, including case series and case reports, since 1966 using the following medical subject heading terms: bone metastases; brain metastases; cough; dyspnea; electrocautery; hemoptysis; interventional bronchoscopy; laser; pain management; pleural effusions; spinal cord metastases; superior vena cava syndrome; and tracheoesophageal fistula.

RESULTS

Pulmonary symptoms that may require palliation in patients who have lung cancer include those caused by the primary cancer itself (dyspnea, wheezing, cough, hemoptysis, chest pain), or locoregional metastases within the thorax (superior vena cava syndrome, tracheoesophageal fistula, pleural effusions, ribs, and pleura). Respiratory symptoms can also result from complications of lung cancer treatment or from comorbid conditions. Constitutional symptoms are common and require attention and care. Symptoms referable to distant extrathoracic metastases to bone, brain, spinal cord, and liver pose additional problems that require a specific response for optimal symptom control. There are excellent scientific data regarding the management of many of these issues, with lesser evidence from case series or expert opinion on other aspects of providing palliative care for lung cancer patients.

CONCLUSIONS

Palliation of symptoms and complications in lung cancer patients is possible, and physicians who provide such care must be knowledgeable about these issues.

Long-term follow-up of ultraflex metallic stents in benign and malignant central airway obstruction

BACKGROUND

We report experience with Ultraflex metallic stents (Boston Scientific, Natick, MA) inserted at rigid bronchoscopy under general anesthesia for palliation of benign and malignant upper airway obstruction.

METHODS

Notes of all patients treated with Ultraflex stents from 1999 to 2003 were reviewed for symptomatic response, spirometric data, and any complications before discharge home. Long-term outcome was assessed by questionnaires sent to patients' general practitioners.

RESULTS

Recruited were 66 patients (12 benign, 54 malignant airway obstructions). Before discharge home, breathlessness improved in 11 of 12 patients with benign obstruction and in 39 of 54 with malignancies. Postoperative complications in 10 patients with malignant obstructions and in 2 patients with benign obstruction were successfully controlled. It was not possible to perform preoperative pulmonary function tests in most of the patients who presented as emergencies. Mean improvement in forced expiratory volume in 1 second was 0.88 liters in 3 patients with benign obstruction and 0.28 liters in 14 patients with malignant obstruction, and mean peak expiratory flow rate improved by 109 L/min and 97 L/min, respectively. General practitioners completed questionnaires for 12 benign patients and 46 of 54 patients with malignancies. At a mean follow-up of 1017 days (range, 46 to 1120 days), 10 of the 12 patients with benign disease were alive and 7 of 46 patients with malignant airway obstruction were alive, with a median survival of 128 days (mean, 361; range, 3 to 1859 days). Most survivors had Medical Research Council grade III breathlessness or better, with few stent-related symptoms.

CONCLUSIONS

Ultraflex stents proved safe and effective in prolonged palliation of benign and malignant airways obstruction.

Benign tracheobronchial strictures: long-term results and factors affecting airway patency after temporary stent placement

OBJECTIVE

The purpose of our study was to evaluate long-term results and identify factors affecting airway patency after temporary placement of a covered, retrievable nitinol stent for benign tracheobronchial strictures.

MATERIALS AND METHODS

Polyurethane or polytetrafluoroethylene (PTFE)-covered retrievable expandable nitinol stents were placed fluoroscopically in 24 patients with benign tracheobronchial strictures. Improvement in respiratory status and complications were evaluated. Maintained patency of airway after temporary stenting was calculated and compared between the 2- and 6-month stenting groups. Factors for maintained patency after temporary stenting were evaluated.

RESULTS

A total of 30 stents were successfully placed and well tolerated in 24 patients. Tissue hyperplasia, stent migration, and bronchial obstruction of the left upper lobe occurred in 36.7%, 13.3%, and 3.3% of patients, respectively. All stents were successfully removed electively either 2 (n = 12) or 6 (n = 12) months after placement or when complications occurred (n = 6). During the follow-up period (mean, 24 months), dyspnea recurred in 15 of the 24 patients. The 6-month stenting group showed a lower recurrence rate (41.7% vs 83.3%, p = 0.045) and a better mean maintained patency (39.7 +/- 7.8 vs 9.4 +/- 5.4 months, p = 0.001) than the 2-month stenting group. Multivariate analysis showed that duration of stent placement (p = 0.002) and the occurrence of tissue hyperplasia (p = 0.026) were associated with maintained patency after temporary stenting.

CONCLUSION

Temporary placement of a covered, retrievable, expandable nitinol stent may be a safe and effective treatment for benign tracheobronchial strictures during the period the stent is in place. A high symptomatic recurrence rate of 62.5% was found after stent removal. Shortterm placement of the stent and tissue hyperplasia were associated with decreased airway patency.

Do Expandable Metallic Airway Stents Have a Role in the Management of Patients With Benign Tracheobronchial Disease?

BACKGROUND

With increasing availability many centers are deploying expandable metallic stents to manage patients with diverse endobronchial disorders. Although these devices have an important role in malignant disease their usefulness in benign large airway disorders is less defined.

METHODS

Between 1997 and 2005, 31 patients aged 34 to 83 years with benign large airway compromise secondary to tracheomalacia (n = 7), posttracheostomy stricture (n = 8), posttracheostomy rupture (n = 2), postpneumonectomy bronchopleural fistula (n = 2), stricture after lung transplantation (n = 3), lobectomy, tuberculosis, traumatic injury to right main bronchus (n = 1 patient each), and external compression of the airway secondary to achalasia, multinodular goiter, aortic aneurysm, right brachiocephalic artery aneurysm, right interrupted aortic arch, and dissecting aneurysm (n = 1 patient each) who were medically unfit for formal surgical intervention were treated by Ultraflex stent deployment. The range of follow-up was 1 week to 96 months. Stents were deployed under anesthesia using rigid bronchoscopy.

RESULTS

Complications included granulation tissue formation (n = 11) treated with Nd: YAG laser ablation, stent migration (n = 1; stent removed, another deployed), metal fatigue (n = 1), stent removal (n = 1), mucus plugging (n = 2), and halitosis (n = 6) difficult to treat despite antibiotics. Thirteen patients died of unrelated causes between 1 week and 15 months after stent deployment.

CONCLUSIONS

Endobronchial metallic stents should be considered only for selected patients with large airway compromise secondary to benign airway diseases for whom other medical comorbidities contraindicate formal airway surgery. Once deployed, they are difficult to remove, are associated with significant complications, and require prospective bronchoscopic surveillance and often further therapeutic intervention.

Treatment of Tracheobronchial Obstruction with a Polytetrafluoroethylene-covered Retrievable Expandable Nitinol Stent

PURPOSE

To evaluate the clinical effectiveness of polytetrafluoroethylene (PTFE)-covered retrievable expandable nitinol stents in tracheobronchial strictures.

MATERIALS AND METHODS

With fluoroscopic guidance, PTFE-covered retrievable expandable nitinol stents were placed in 15 symptomatic patients with benign (n = 6) or malignant (n = 9) tracheobronchial strictures. Complications and improvement in respiratory status were evaluated. Stents were removed electively 6 months after placement in benign strictures or if complications occurred. Membrane degradation or separation from the wire mesh was evaluated in removed stents.

RESULTS

A total of 17 stents were successfully placed and were well tolerated in all patients. Sputum retention, stent migration, and tissue hyperplasia occurred in 23.5% (n = 4), 17.6% (n = 3), and 17.6% (n = 3) of stents, respectively. A total of 11 stents were successfully removed electively 6 months after placement (n = 4) or when complications occurred (n = 7). All 11 such stents were removed without difficulty with use of standard techniques, antecedent balloon dilation being necessary in two cases as a result of tissue hyperplasia. No removed stent showed signs of membrane degradation, and two removed stents showed signs of membrane separation from the mesh.

CONCLUSIONS

PTFE-covered retrievable expandable nitinol stents were effective in the treatment of tracheobronchial strictures. Stent removal was easy with use of standard techniques, and no removed stent showed evidence of membrane degradation.

Airway management of patients with tracheobronchial stents

The use of tracheobronchial stents for compromised large airways is increasing. We provide a case series highlighting some of the complications of airway management in patients with tracheobronchial stents in situ and propose an approach for dealing with this potentially complicated situation.

Short-term deployment of self-expanding metallic stents facilitates healing of bronchial dehiscence

Bronchial dehiscence after lung transplantation is difficult to treat and associated with high mortality. We describe our experience using self-expanding metallic stents to treat post-lung transplant bronchial dehiscence. From January 1995 to June 2004, 189 single and 118 double lung transplants were performed in our institution, totaling 425 at-risk bronchial anastomoses. Seven (1.6%) incidents of life-threatening bronchial dehiscence were treated with self-expanding metallic stents. The interval between transplant and diagnosis of dehiscence was 29.1 +/- 18.5 days. All patients presented with respiratory distress, and three required mechanical ventilation. Self-expanding metallic stent placement resulted in complete bronchial healing. All three patients with respiratory failure requiring mechanical ventilation were successfully weaned after stent placement. In two later cases, the stents were electively removed after adequate healing of the dehiscence. Complications included stent migration (one patient) and in-stent stenosis (three patients). Two of these patients required repeat stent insertion after removal, due to bronchomalacia. In patients with life-threatening bronchial dehiscence, self-expanding metallic stents offer prospects for a successful outcome. Self-expanding metallic stents are known to be associated with significant granulation tissue formation, and this property provides a platform for healing of dehiscence and, in time, peribronchial soft tissue grows in to cover the defect, allowing stent removal.