Prospective Observational Trial of a Nonocclusive Dilatation Balloon in the Management of Tracheal Stenosis

OBJECTIVES

Tracheal stenosis is a debilitating condition that often presents as an emergency and is challenging to treat. Dilatation may avoid tracheostomy or costly tracheal resection and reconstruction. Traditional dilators cause complete occlusion, preventing oxygenation and ventilation, limiting the safe duration of dilatation, and increasing the risk of hypoxic injury or barotrauma. The study authors here assessed an innovative nonocclusive tracheal dilatation balloon, which may improve patient safety by allowing continuous gas exchange.

DESIGN

A prospective observational study of 20 discrete dilatation procedures performed in 13 patients under general anesthesia. The primary outcomes were the ability to ventilate during dilatation and the preservation of peripheral oxygen saturation. Secondary outcomes included a measured reduction in stenosis, improvement in Cotton-Myer grading, and procedure-related adverse events.

SETTING

At a single university (academic) hospital.

PARTICIPANTS

Consenting adult patients with acquired tracheal stenosis.

INTERVENTIONS

Access to the airway was maintained by a rigid bronchoscope or supraglottic airway device, as deemed appropriate. Continuous conventional ventilation was provided during 3-minute balloon dilatations.

MEASUREMENTS AND MAIN RESULTS

Heart rate, airway pressure, end-tidal carbon dioxide partial pressure, and peripheral oxygen saturation were measured, and adverse events were recorded. Ventilation was satisfactory in all patients. Peripheral saturation remained greater than 94% in 19 of the 20 (95%) procedures. Stenosis internal diameter and grading were improved. Two patients had minor reversible adverse events (coughing and laryngospasm), which did not prevent completion of the procedure.

CONCLUSIONS

The authors report the first human trial of the device, in which continuous conventional ventilation could be provided during all tracheal balloon dilatation procedures. Larger trials are needed to confirm improved patient safety and comparative efficacy.

Tracheal rupture after vocal cord polyp resection: A case report

INTRODUCTION

Transoral laser microsurgery (TLM) is one of the most common operations performed for glottic lesions. Several protection measures are taken to prevent tracheal damage. However, some protection measures and common postoperative complications may still cause delayed tracheal rupture in certain situations. Cases of tracheal rupture after surgery are extremely rare, and there are no previous reports of TLM of the glottis causing tracheal rupture.

PATIENT CONCERNS

A middle-aged woman who underwent TLM for bilateral vocal cord polyps developed sudden neck pain, followed by cough and subcutaneous emphysema.

DIAGNOSIS

She underwent head, neck, and chest computed tomography (CT), which revealed a 4-cm membranous tracheal tear located 4.5 cm distal to the glottis, pneumomediastinum, and subcutaneous emphysema extending from the base of skull to the chest.

INTERVENTIONS

The patient underwent an emergency surgical surgical chest exploration and tracheal repair.

OUTCOMES

One month after the surgery, the patient fully recovered with no tracheal stenosis or respiratory dysfunction.

CONCLUSIONS

Conventional protective measures and common postoperative complications of TLM may also cause tracheal rupture.

State of the Science in Tracheal Stents: A Scoping Review

OBJECTIVE

Recent material science advancements are driving tracheal stent innovation. We sought to assess the state of the science regarding materials and preclinical/clinical outcomes for tracheal stents in adults with benign tracheal disease.

METHODS

A comprehensive literature search in April 2021 identified 556 articles related to tracheal stents. One-hundred and twenty-eight full-text articles were reviewed and 58 were included in the final analysis. Datapoints examined were stent materials, clinical applications and outcomes, and preclinical findings, including emerging technologies.

RESULTS

In the 58 included studies, stent materials were metals (n = 28), polymers (n = 19), coated stents (n = 19), and drug-eluting (n = 5). Metals included nitinol, steel, magnesium alloys, and elgiloy. Studies utilized 10 different polymers, the most popular included polydioxanone, poly-l-lactic acid, poly(d,l-lactide-co-glycolide), and polycaprolactone. Coated stents employed a metal or polymer framework and were coated with polyurethane, silicone, polytetrafluoroethylene, or polyester, with some polymer coatings designed specifically for drug elution. Drug-eluting stents utilized mitomycin C, arsenic trioxide, paclitaxel, rapamycin, and doxycycline. Of the 58 studies, 18 were human and 40 were animal studies (leporine = 21, canine = 9, swine = 4, rat = 3, ovine/feline/murine = 1). Noted complications included granulation tissue and/or stenosis, stent migration, death, infection, and fragmentation.

CONCLUSION

An increasing diversity of materials and coatings are employed for tracheal stents, growing more pronounced over the past decade. Though most studies are still preclinical, awareness of tracheal stent developments is important in contextualizing novel stent concepts and clinical trials. Laryngoscope, 2021.

Pediatric tracheal trauma

Tracheal trauma is an uncommon but potentially serious cause of airway injury in children. Presentation may be acute in cases of blunt or penetrating trauma, or delayed in cases of chronic irritation or indwelling endotracheal tubes. Symptoms include dyspnea, progressive respiratory distress, neck and chest swelling and ecchymosis, and dysphonia. Workup is pursued as allowed by the patient's clinical status and may include plain radiography, computed tomography, and endoscopy. Accuracy and efficiency of diagnosis is paramount for those at risk of rapid decompensation. Treatment may include observation, elective and strategic intubation, or primary surgical repair.

Therapeutic bronchoscopy for central airway diseases

Over the past century rigid bronchoscopy has been established as the main therapeutic means for central airway diseases of both benign and malignant aetiology. Its use requires general anaesthesia and mechanical ventilation usually in the form of manual or high-frequency jet ventilation. Techniques applied to regain patency of the central airways include mechanical debulking, thermal ablation (laser, electrocautery and argon plasma coagulation) and cryo-surgery. Each of these techniques have their advantages and limitations and best results can be attained by combining different modalities according to the type, location and extent of the airway blockage. If needed, deployment of airway endoprostheses (stents), as either fixed-diameter silicone or self-expandable metal stents, may preserve the airways patency often at the cost of several complications. Newer generation of customised stents either three-dimensional printed or drug-eluting stents constitute a promise for improved safety and efficacy results in the near future. Treating central disease of benign or malignant aetiology, foreign body aspiration or massive bleeding in the airways requires a structured approach with combined techniques, a dedicated team of professionals and experience to treat eventual complications. Specific training and fellowships in interventional pulmonology should therefore be offered to those who wish to specialise in this field.

Superior Strategy in Benign Tracheal Stenosis Treatment: Surgery or Endoscopy?

INTRODUCTION

 Due to the variations in (laryngeal) tracheal stenosis (TS) patient groups, there is still no consensus on which patient should be treated with endoscopy or surgery. The aim of the present study was to generate an algorithm in the light of the related literature and the data obtained from a clinic where both endoscopic and surgical treatments are conducted.

METHOD

 A retrospective analysis was performed on the data of a total of 56 patients during 2013 to 2019. A total of 38 patients were subject to surgery with 31 as a first treatment option and 7 due to the unsatisfactory results of endoscopic treatments. Endoscopic approaches were tried on a total of 29 patients with 25 as initial treatment and 4 due to postsurgical recurrence.

RESULTS

 Symptomatic full control ratio was determined as 69% with endoscopic treatments, 89.5% in subglottic stenosis (SGS) surgery (n = 19), and 89.5% in trachea surgery (n = 19). However, success rates with no recurrence were determined, respectively, as 40.0, 36.4, and 36.4% for patients subject to dilatation, stent, or T tube treatment. Dilatation was observed to be successful in patients with stenotic segment lengths of less than 1.5 cm (p = 0.02). Failure rates increased in SGS (p = 0.03) and TS (p = 0.12) in the surgical group with increasing stenotic segment length. The presence of comorbidities was not effective on treatment success.

CONCLUSION

 Endoscopic methods are preferred in cases of web-like stenosis. Surgical methods should first be considered for other patients and endoscopic methods should be used on patients who are not suited for surgery or in cases of postsurgical recurrence.

Effects of supramaximal balloon dilatation pressures on adult cricoid and tracheal cartilage: A cadaveric study

OBJECTIVES/HYPOTHESIS

Cricoid fracture is a serious concern for balloon dilatation in airway stenosis. Furthermore, there are no studies examining tracheal rupture in balloon dilatation of stenotic segments. The aim of this study was to evaluate the effect of supramaximal pressures of balloons on the cricoid and tracheal rings.

STUDY DESIGN

Prospective cadaveric study.

METHODS

Seven cadaveric laryngotracheal complexes of normal adults with intact cricothyroid membranes were acquired. Noncompliant vascular angioplasty balloons (BARD-VIDA) were used for dilatation. The subglottis and trachea were subjected to supramaximal dilatation pressures graduated to nominal burst pressure (NBP) and, if necessary, rated burst pressure (RBP). Larger-diameter balloons, starting from 18 mm size to 24 mm, were used. Dilatations were maintained for 3 minutes.

RESULTS

The cricoid ring was disrupted by larger-diameter balloons (22 mm and 24 mm) even at lower pressures (less than NBP) in six cases. Tracheal cartilages were very distensible, and external examination after supramaximal dilatation (24 mm close to RBP) revealed no obvious cartilage fractures or trachealis tears. Histopathological examination revealed sloughing of mucosa in the areas corresponding to balloon placement, but no microfractures or disruption of the perichondrium of tracheal ring cartilages.

CONCLUSIONS

These results indicate that the cricoid is vulnerable to injury from larger balloons even at lower dilatation pressures. The tracheal cartilages and the membranous wall of the trachea remained resilient to supramaximal dilatation and larger balloons.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:1304-1309, 2018.