Complications of metallic stents in the pediatric airway.

OBJECTIVE: Our aim was to present our experience with complications caused by placement of metallic stents in the pediatric airway. DESIGN AND SETTING: We conducted a retrospective study of the medical records of patients with complications resulting from metallic stent placement, managed by the senior authors between 1993 and 2002. RESULTS: Nine children had complications associated with the placement of metallic airway stents. Of these, 8 children required stent removal. Granulation tissue and tracheal stenosis were seen in all 7 children with long standing stent placement. There was 1 stent death in this series. CONCLUSIONS: Metallic airway stents can cause significant complications in the pediatric airway. These complications may supersede the airway compromise that necessitated their initial placement. As such, metallic stent placement should be approached with caution. The likelihood and severity of complications increase with time, as do the difficulties encountered upon removal. The proportion of patients in whom metallic stents may be placed "permanently" without complications is not known. Therefore we recommend that metallic airway stents be considered a temporizing measure of limited duration.     

Double stenting for esophageal and tracheobronchial stenoses

Background. We examined the complications and outcomes of placing stents for both esophageal and tracheobronchial stenoses.

Methods. We placed stents for both esophageal and tracheobronchial stenoses in 8 patients (7 with esophageal cancer and 1 with lung cancer). Covered or noncovered metallic stents were used for the esophageal stenoses, except in 1 patient treated with a silicone stent. Silicone stents were used for the tracheobronchial stenoses. The grades of esophageal and tracheobronchial stenoses were scored.

Results. All patients experienced improvement of grades of both dysphagia and respiratory symptoms after stent therapy. The complications were: (1) 2 patients suffered respiratory distress after placement of the esophageal stent because of compression of the trachea by the stent; and (2) 3 patients developed new esophagotracheobronchial fistulae, and 2 patients had recurring fistula symptoms because of growth of preexisting fistulae after the stent placement, which were caused by pressure from the 2 stents. Despite the fistulae, the 5 patients treated with covered metallic stents did not complain of fistula symptoms, but 2 patients treated with noncovered metallic or silicone stents did complain.

Conclusions. For patients with both esophageal and tracheobronchial stenoses, a stent should be introduced into the tracheobronchus first. Because placement of stents in both the esophagus and tracheobronchus has a high risk of enlargement of the fistula, a covered metallic stent is preferable for esophageal cancer involving the tracheobronchus.     

The role of airway stenting in pediatric tracheobronchial obstruction

OBJECTIVE: Tracheobronchial obstruction is infrequent in the pediatric age group but it is associated with significant morbidity and mortality. The purpose of this study is to review the results of a single institution experience with endoscopic stent placement in children with benign tracheobronchial obstruction, and with special concern on safety and clinical effectiveness. MATERIALS AND METHODS: Twenty-one patients with severe airway stenosing disease in which stent placement was performed between 1993 and 2006. Inclusion criteria according to the clinical status were: failure to wean from ventilation, episode of apnea, frequent respiratory infections (>3 pneumonia/year), and severe respiratory distress. Additional criteria for stent placement were: failure of surgical treatment, bronchomalacia, and tracheomalacia refractory to previous tracheostomy. Selection of the type of stent depended on the site of the lesion, the patient's age, and the stent availability when time of presentation. The following variables were retrospectively evaluated: age, type of obstruction, associated malformations, stent properties, technical and clinical success, complications and related reinterventions, outcome and follow-up period. RESULTS: Thirty-three stents were placed in the trachea (n=18) and/or bronchi (n=15) of 21 patients with a median age of 6 months (range, 9 days-19 years). Etiology of the airway obstruction included severe tracheomalacia and/or bronchomalacia in 19 cases (90%), and postoperative tracheal stenosis in two. Twelve children had a total of 20 balloon-expandable metallic stents placed, and 10 had 13 silicone-type stents (one patient had both). In nine patients (42%) more than one device was placed. Stent positioning was technically successful in all but one patient. Clinical improvement was observed in 18 patients (85%) but complications occurred in five of them (27%). Eight patients died during follow-up but only in one case it was related to airway stenting. Thirteen patients (62%) are alive and in good condition with a mean follow-up of 39 months (1-13.8 years). CONCLUSIONS: Although the results were based on a small series, placement of stents in the pediatric airway to treat tracheobronchial obstruction seems to be safe and effective. Stenting is a satisfactory therapeutic option when other procedures have failed or are not indicated.     

A new intratracheal stent for tracheobronchial reconstruction: experimental and clinical studies

An intraluminal tracheal stent (ITS) was used experimentally in rabbits and piglets, as well as clinically in infants with tracheal stenosis, to facilitate airway reconstruction. The ITSs were constructed of stainless-steel springs covered with silicone rubber. They were implanted in seven piglets (6 to 8 kg), five rabbits (3 to 5 kg) and three infants. No animals developed severe respiratory distress and all appeared to tolerate the ITS. Postmortem examinations 1 to 8 weeks after surgery showed (1) loss of stent fixation (one pig), (2) increased tracheal secretions, (3) pneumonia (one pig, two rabbits), and (4) focal squamous metaplasia of tracheal mucosa. Stents used to treat three infants (2 to 5 months of age) with complex tracheobronchial stenosis were placed at the time of periosteal tracheoplasty in two. Recurrent stenosis necessitated a second tracheoplasty and stenting in one, and a long tracheostomy tube and balloon dilatations in the other. The third child had endoscopic stent insertion to alleviate severe airway collapse after esophageal tracheoplasty. The child died from progressive respiratory failure after stent dislodgment. Although the stents were well tolerated in animals and they enhanced critical ventilation of all pulmonary lobes in infants after tracheal reconstruction, certain modifications such as alternative methods of fixation, accommodation for tracheal growth, and reduction in tissue reactivity are necessary before further use of the ITS can be advocated.     

气管支架置入术治疗气管恶性狭窄的并发症分析

目的探讨应用气管支架治疗气管恶性狭窄的并发症。方法回顾性分析1999年11月—2011年6月在局麻和数字减影血管造影机下应用气管支架治疗气管恶性狭窄的25例患者资料,其中6例置入Z型不锈钢支架,19例置入镍钛记忆合金支架,观察支架相关并发症。结果置入Z型不锈钢支架的6例患者中,所有支架置入后即刻完全扩张,2例出现支架移位,随访期中支架再狭窄3例,其中肿瘤增生性狭窄1例,黏稠痰液阻塞性狭窄1例,支架断裂伴肉芽增生性狭窄1例;置入镍钛记忆合金支架的19例患者中,术中无支架移位,2例即刻完全扩张,17例术后3天～3个月扩张完全,随访期内支架再狭窄2例,其中肿瘤增生性狭窄1例,肉芽增生性狭窄1例。所有患者术后呼吸困难即刻明显改善。结论应用气管支架治疗气管恶性狭窄有一定并发症,但仍是一种作用迅速、效果显著的治疗措施。     

Stenting for airway obstruction in the carinal region

Background. Recent progress on airway stents has provided sufficient airway patency for patients with airway obstruction; however, when the stenosis exists in the carinal zone, establishing an excellent airway condition is still troublesome because of the anatomic structure.

Methods. We treated 15 patients with severe tracheobronchial stenosis involving a carinal bifurcation region, using several types of stenting devices (long T-tube, T-Y tube, wire reinforced Y tracheostomal tube, Freitag Dynamic stent [Karl Storz, Tuttlingen, Germany], and covered metallic stent). All patients had advanced inoperable tumors (lung cancer, n = 6; esophageal cancer, n = 3; thyroid cancer, n = 3; mediastinal tumor, n = 3).

Results. All but 2 patients had immediate relief of respiratory symptoms. One patient died of respiratory failure caused by pulmonary lymphatic spread 3 days after Dynamic stent insertion. In 1 patient with severe left main bronchial stenosis due to lung cancer, effective palliation was not achieved by insertion of a covered metallic stent because of its insufficient expansion against the stenosis. Mean survival after successful stenting was 4.3 months (range, 1 to 15 months). There were no complications directly attributable to the stents.

Conclusions. As evidenced by the clinical effectiveness, airway stenting for inoperable tumor is valuable in such patients. Choosing a stent that will fully cover the lesion and allow sufficient tolerance against compression is important to successful stenting. Benefits such as ease of phonation and stent maintenance should also be considered.     

Bougienage and balloon dilation using a conventional tracheal tube for tracheobronchial stenosis before stent placement

In order to achieve urgent restoration of the airways in tracheobronchial stenosis and to make stent placement simpler and safer, we developed a method that allows combined bougienage and balloon dilation via the use of a conventional tracheal tube. Fifteen patients with tracheobronchial stenosis underwent bougienage and balloon dilation using a tracheal tube with a cuff attached, inserted via a tracheostomy, before stent placement. The conventional tracheal tube was inserted via a tracheostomy, the cuff was expanded at the stenotic site, and the tube was fixed to the tracheostomy and left in place for a few days until sufficient dilation was achieved. This procedure was conducted on the trachea in 10 patients, the left main bronchus in three patients, and the right main bronchus in two patients. In all patients, the procedure immediately relieved the obstructive symptoms and dilated the stenosis sufficiently. Thereafter, Dumon stents were inserted in 10 patients, dynamic stents in four patients, and an expandable metallic stent in one patient. The stents were introduced easily with no other dilation procedure after a mean of 5 days from the start of the procedure. For tracheobronchial stenosis, bougienage and balloon dilation using a tracheal tube with an integral cuff via a tracheostomy is a simple and safe method for achieving both urgent relief of airway stenosis and dilation before stent placement. Received: 20 May 1999/Accepted: 17 December 1999/Online publication: 25 April 2000     

Self-expanding tracheobronchial stents using flexible bronchoscopy

Endoscopic insertion of tracheobronchial stents is indicated to achieve patency of the airway in case of malignant or benign obstructing lesions. Until now, the placement of prostheses has required a rigid bronchoscope with specially designed insertion instruments. Self-expanding stents are currently used to treat stenoses of different hollow organs (vessels, urinary tract, gastrointestinal tract, bile duct, respiratory tract). We report the first case of a self-expanding stent implanted in the trachea and right main stem bronchus using flexible videobronchoscope under local anesthesia. The procedure was easy, safe, effective, and well tolerated. No complications occurred.     

Anesthetic management of tracheobronchial stent insertion and extracorporeal lung assist (ECLA)

We experienced eight cases of general anesthesia for tracheobronchial stent insertion. All stents were Ultraflex stent (Boston Scientific, Tokyo), and they were inserted guided by bronchofiberscopy under general anesthesia. Anesthesia was induced with patients under spontaneous breathing, and we inserted a tracheal tube or a laryngeal mask airway. Anesthesia was maintained with propofol and sevoflurane. In four cases with severe tracheobronchial stenosis, we used venovenous extracorporeal lung assist (ECLA) before general anesthesia induction. Oxygenation during stent insertion was well-maintained in all patients. We must evaluate the severity of tracheobronchial stenosis preoperatively. In high risk cases anticipated of airway obstruction, ECLA should be used for safe anesthetic management.     

Complication of benign tracheobronchial strictures by self-expanding metal stents

OBJECTIVES: Self-expanding metal stents are used to palliate benign strictures. We examined the complications of this approach. METHODS: Between 1997 and 2002, we observed recurrent airway obstruction and extension of benign inflammatory strictures after the placement of tracheobronchial Microvasive Ultraflex stents and Wallstents (Boston Scientific Corp, Natick, Mass), in 10 patients with postintubation strictures and 5 with other indications; all but 1 patient were referred to us. Patients with tracheal (9), subglottic (1), combined tracheal and subglottic (3), and bronchial (2) strictures had been treated with covered and uncovered Wallstents (6) and Microvasive Ultraflex stents (9). RESULTS: After stent insertion, stricture and granulations within previously normal airway were seen in all patients. New subglottic strictures resulting from the stent caused hoarseness in 4 patients. A bronchoesophageal fistula was found in 1 patient at presentation and a tracheoesophageal fistula in another during extraction of a Wallstent. Primary surgical reconstruction, judged to have been feasible before wire stent insertion in 10 patients, was possible after stenting in only 7 and failed in 2. Palliative tubes were placed in 60% (9/15). Self-expanding metal stents may lengthen luminal damage, incite subglottic strictures, and cause esophagorespiratory fistula in inflammatory airway strictures. The injury is severe, occurs after a short duration of stenting, and precludes definitive surgical treatment or requires more extensive tracheal resection. CONCLUSION: The current generation of self-expanding metal stents should be avoided in benign strictures of trachea and bronchi.     

The management of post-intubation tracheal stenoses with self-expandable stents: early and long-term results in 11 cases

Objective: The optimal management of post-intubation tracheal stenoses is surgical reconstruction of the airway. Stenting of the trachea using silastic T-tubes or one of the various types of tracheal stents are the alternative ways to surgical reconstruction for the management of post-intubation tracheal stenoses. The early and long-term results of 11 patients with post-intubation tracheal stenosis, who underwent tracheal stenting with self-expandable metallic stents (SEMSs), are presented. Methods: Twelve patients (10 men, mean age: 47.8 ± 20.4 years) with post-intubation tracheal stenosis were referred for tracheal stenting with SEMS (2000–2004). In three cases, the upper tracheal stenosis extended within the subglottic larynx. Stenting was successful in 11 patients, while, in one patient with involvement of the subglottic larynx, the attempt to insert the stent failed. Follow-up time varied from 6 to 96 months, and it was made with virtual and fiberoptic bronchoscopy. Results: Immediate relief of obstructive symptoms was observed in all the 11 patients, where an SEMS was successfully inserted. Stent dislodgement occurred shortly after the procedure in two patients, and it was treated with insertion of a new stent in the first case and a stent-on-stent insertion in the second. Good patency of the stent was observed in three patients for 60–96 months. Three patients with good patency of the stent died from other reasons 24–48 months after stent insertion. Four patients developed obstructive granulation tissue at the ends of the stent after 12–43 months, requiring further treatment with thermal lasers and/or tracheostomy. One patient underwent stent removal and successful laryngotracheal reconstruction 6 months after stent insertion. Conclusions: The application of SEMS in post-intubation tracheal stenoses results in immediate improvement of obstructive symptoms without significant perioperative complications. SEMSs have the potential risks of migration and of granulation tissue formation at the end of the stent. SEMS should be applied only in strictly selected patients with post-intubation tracheal stenosis, who are considered unfit for surgery and/or with limited life expectancy.     

Tracheobronchial stents for management of airway stenosis

Airway prostheses provide an excellent method for providing relief for patients with malignant or benign stenoses. Two types of prostheses are currently available: rigid silicone stents and metallic expandable stents. Silicone stents have been proven to be well tolerated, nonreactive, and easily removable during several decades of clinical application. However, they impair the drainage of sputum because of interrupted ciliary movement. Subsequently, retained secretions within the stent lumen can be obstructive. In addition, dislodgment frequently occurs because of their rigidity. The advantages of metallic expandable stents are as follows: 1) they can be inserted under local anesthesia with relative simplicity: 2) they do not impair the drainage of sputum: 3) ventilation is usually possible even if the metallic mesh stent covers another bronchus: and 4) their flexibility allows them to bend and conform better than rigid stents to tortuous airway stenoses. The disadvantages of metallic stents are: 1) tumor or granulation ingrowth can occur because of their porosity: 2) removal is difficult: and 3) there is limited experience with their use because they have only recently been employed for airway stenoses.     

Gianturco self-expanding metallic stents in treatment of tracheobronchial stenosis after single lung and heart and lung transplantation

Three patients with recurrent bronchial stenosis following single lung transplant (SLTx), and one patient with tracheal stenosis following heart-lung transplantation (HLTx), not responding to repeated dilatations (3 patients) and prolonged use of silastic stents (patient with tracheal stenosis), have been treated by the endoscopic insertion of Gianturco self-expanding metallic stents under fluoroscopic control. The stent resulted in immediate improvement in respiratory function in all four patients. One patient (SLTx) had early bronchial re-stenosis due to growth of granulation tissue within the stent which was successfully treated by cryotherapy. In one patient (HLTx), a left lower lobe bronchial stenosis developed 14 months after tracheal stenting. The metallic stent appears to be a promising device in the management of recurrent or resistant bronchial stenosis following SLTx or tracheal stenosis after HLTx.     

Anesthesia and airway management for removing pulmonary self-expanding metallic stents

The use of bronchoscopically placed self-expanding metallic stents (SEMS) and silastic stents in patients suffering from tracheobronchial stenosis or similar problems has proven to be an important clinical option. When complications occur, it may be necessary to remove the device. Removal of a SEMS is usually performed during general anesthesia with muscle relaxation and positive pressure ventilation, often using total intravenous anesthesia. Airway management depends on stent type and location. Intubating patients' tracheas with a tracheal stent requires special caution, as it risks damaging tissue and dislodging the stent distally. Potential complications with removal include tracheal disruption, retained stent pieces, mucosal tears, re-obstruction requiring new stent placement, the need for postoperative ventilation, pneumothorax, damage to the pulmonary artery, and death.     

Anesthetic management for placement of tracheobronchial stents in patients with airway stenosis

We report the anesthetic management for stents placement in patients with tracheobronchial stenosis. The subjects were 6 patients with lung cancer and one patient with tracheal invasion of esophageal cancer. Anesthesia was induced with propofol, fentanyl and vecuronium, and maintained with propofol and vecuronium. After intubation, tracheostomy was performed. The patients were kept apnic during insertion of stents. Three patients had dynamic stents inserted from tracheostomy site and one orally. Three patients had Dumon stents inserted orally, but the procedure in one patient was cancelled because her stent could not be placed at appropriate position. We recommend the anesthetic management through the tracheostomy site for the placement of Dumon tubes or dynamic stents.     

Development of a new insertion technique and a new device for the placement of bifurcated airway stents

We developed a new insertion technique and designed a forceps device for the placement of bifurcated airway stents; 131 of 142 endoscopically placed tracheobronchial Y-stents were inserted with a forceps and a laryngoscope. For the last 52 stent implantations we used the new stent forceps. It was determined to be a simple and safe method without major complications. In 11 cases alternative techniques had to be used. Technique and device are described in detail.     

Secondary Carina and Lobar Bronchi Stenting in Patients with Advanced Lung Cancer: Is It Worth the Effort? A Clinical Experience

Background: The lobar airway stenting remains an endoscopic procedure not well standardized in patients with locally advanced lung cancer disease. The goal of this study was to evaluate technical feasibility, clinical outcome, and complications of different stents in patients with malignant lesions involving lobar bronchi, primary and secondary carina.Methods: Between November 2008 and October 2013, we retrospectively analyzed 146 patients with benign and malignant tracheobronchial stenosis who underwent airway stent insertion below main carina and main bronchi.Results: In all, 170 airway stenting procedures were performed on 146 patients. In all, 51 of them with malignant peripheral airway stenosis underwent stents placement below main carina. In all but one patient, the deployment of stents was successful with improvement of symptoms. The chest radiograph after the procedure detected the lung re-expansion in 29 of 51 patients. The mean follow-up duration was 123 days ± 157. Complications observed included stent migration, tumor overgrowth, infections, granulation tissue formation, and obstruction due to tenacious secretions. Longer survival was observed in patients who received additional treatment after airway stenting compared to those who did not (p <0.01).Conclusions: Stenting of lobar bronchi and primary or secondary carina is technically feasible, effective, and acceptably safe.     

Use of Gianturco self-expandable stents in the tracheobronchial tree

Gianturco self-expandable stents were used successfully in the management of 5 patients with tracheobronchial pathology. Placement was performed under endoscopic and fluoroscopic guidance. None of the patients has experienced complications secondary to the stent placement, and in all of them the clinical problems resolved satisfactorily. Longer follow-up is required to determine the place of tracheobronchial stenting in patients with respiratory compromise.     

气管内支架治疗气管良性狭窄11例

目的：探讨气管内支架治疗气管良性狭窄的疗效。方法：１９８２年２月至１９９８年８月间应用气管内支架治疗１１例气管良性狭窄,其中Ｙ形硅胶管支架置入术４例,Ｓｔｒｅｃｋｅｒ金属网状支架置入术１例。结果：随访４￣１８０个月。８例临床效果良好,其中４例拔除内支架。并发症包括肉芽组织形成３例,其中２例更换支架;围术期咳痰困难５例。结论：不同病因良性气和狭窄在选择治疗方法时应严格按照治疗原则,对气管壁全层皆已成     

Anesthetic management of tracheobronchial stent insertion in patients who underwent laser resection, balloon dilatation and tracheostomy in advance

BACKGROUND: We report successful management of tracheobronchial stent insertion under general anesthesia. METHODS: In thirty-two cases, tracheobronchial stent insertion was performed under general anesthesia. The technique for airway management was chosen depending on the type of stent or the constriction level of the airway portion. We employed tracheostomy in order to avoid repeated intubations during the insertion of Dumon or Dynamic stent. In case of severe airway stenosis, laser resection or balloon dilatation was performed before stent insertion. RESULTS: We had 32 successful cases in 36 trials. Four trials failed due to insufficient expansion in one, mismatches of stent angle in one and pneumomediastinum in one. There was no exacerbation of respiratory condition in failed cases. There was no case who needed percutaneous cardiopulmonary support system. CONCLUSIONS: We managed tracheobronchial stent insertion under general anesthesia. Both the airway expansion by laser resection or balloon dilatation before stent insertion and also the insertion of Dumon or Dynamic stent through a tracheostomy were helpful strategies. These techniques facilitated more definitive airway maintenance and stable anesthetic management.