Successful surgical management of a tracheopulmonary artery fistula caused by an intratracheal expandable metal stent

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.

Tracheobronchial stents in children

Tracheobronchial obstruction is infrequent in children and still remains a challenging matter of concern. Management alternatives vary from conservative treatment to complex surgical techniques or endoscopic interventional procedures. Airway stenting in children is relatively recent and follows the trail of the experience in adult patients. Nevertheless, there are basic differences between both age groups like the benign nature of most obstructions and the small size of the pediatric airway. These specific features raise the issues of the precise role of tracheobronchial stenting in children and the selection of the most adequate device. Stents fall into four main categories according to the material they are made of: metallic, plastic, hybrid, and biodegradable. Each type has its own advantages and drawbacks so the ideal stent is not yet available. Despite increasing experience with stenting, definite clinical criteria for their use in children are yet to be established. Even so, there seems to be a basic general agreement that stents may play a role in particular clinical settings in which there are no other therapeutic options.

Abnormal cardiac axis as a prenatal marker of left pulmonary artery sling

Left pulmonary artery sling (LPAS) is a rare vascular anomaly. The left pulmonary artery arises distally from the right pulmonary artery on the right side of the trachea and passes between the trachea and esophagus towards the left lung, compressing the lower trachea. LPAS is associated with congenital tracheal stenosis, which frequently requires early surgical intervention and has a poor prognosis due to severe airway obstruction after birth. Therefore, LPAS should be prenatally diagnosed to prepare for surgical intervention for tracheal stenosis. To the best of our knowledge, there are few reports on prenatal echocardiographic findings in LPAS. We report three prenatal cases of LPAS, which resulted in respiratory symptoms. We discuss fetal ultrasound findings and highlight the abnormal rotation of the fetal cardiac axis to the right as a useful sign in the prenatal screening of LPAS.

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.

Tuberculous hilar lymph nodes leading to tracheopulmonary artery fistula and pseudoaneurysm of pulmonary artery

Tracheopulmonary artery fistula is an extremely rare condition. We report the case of an 80-year-old man who presented with massive hemoptysis. He was found to have tuberculous mediastinal lymph nodes that had eroded into the pulmonary artery and anterior tracheal wall, leading to a pseudoaneurysm of the right pulmonary artery and a tracheopulmonary artery fistula.

Tracheal obstruction caused by an expandable metallic stent: a case of successful removal of the stent

We report a case of tracheal obstruction caused by an expandable metallic stent. A 3-month-old girl with severe tracheomalacia had a placement of a Palmaz stent. At 3 years of age, she developed progressive dyspnea. The CT scan showed tracheal obstruction caused by granulation tissue over the stent. At operation, the stent was found to have penetrated the posterior tracheal wall. Under partial cardiopulmonary bypass, the stent was removed along with the membranous wall of the trachea, and the trachea was reconstructed using slide tracheoplasty. Tracheal obstruction is one of the serious complications caused by an expandable metallic stent. Direct open approach to the trachea under cardiopulmonary bypass is thought to be a safe way to manage this problem.

Multislice CT Evaluation of Airway Stents

Tracheobronchial stents are playing an increasing role in the palliative treatment of large airway obstruction due to a variety of conditions, including extrinsic compression, intraluminal disease, and malacia. Computed tomography (CT) plays an important role in aiding planning of stent placement and in detecting various stent complications. In this pictorial essay, we illustrate and review the role of multislice CT in the pre- and post-stent placement settings. A special emphasis is placed upon the characteristic CT appearance of specific stent complications and upon the role of CT multiplanar reformations and 3-dimensional (3-d) reconstruction techniques.

Tracheobronchial intervention in children

Disorders of the major airways in children are often difficult to treat. Recent advances in interventional radiology are proving useful, for both assessment of the severity of the problem and treatment. Flexible bronchoscopy and bronchography are essential tools for diagnosis, intervention and follow-up. Echocardiography, computed tomography and magnetic resonance imaging may also be important for the evaluation of cardiovascular anomalies, which are often associated with airway obstruction. Surgery remains the first line of treatment for most congenital abnormalities of the airway and for cardiac anomalies that cause airway compression. Balloon dilatation and stenting are helpful in certain other conditions, as well as in children whose airway problem is not fully corrected by surgery. A multidisciplinary approach is required, with input from pediatric cardiothoracic surgeons, radiologists, radiographers, otolaryngologists, pulmonologists, anesthesiologists, intensivists, physiotherapists and liaison nurses.

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.