Operative or non-operative treatment of congenital tracheal stenosis: is there something new?

Composite Biosynthetic Graft for Repair of Long-Segment Tracheal Stenosis: A Pilot In Vivo and In Vitro Feasibility Study

Pediatric patients who undergo surgery for long-segment congenital tracheal stenosis (LSCTS) have suboptimal outcomes and postsurgical complications. To address this, we propose a biosynthetic graft comprising (1) a porcine small intestinal submucosa extracellular matrix (SIS-ECM) patch for tracheal repair, and (2) a resorbable polymeric exostent for biomechanical support. The SIS-ECM patch was evaluated in vivo in an ovine trachea model over an 8 month period. Concurrently, the biosynthetic graft was evaluated in a benchtop lamb trachea model for biomechanical stability. In vivo results show that SIS-ECM performs better than bovine pericardium (control) by preventing granulation tissue/restenosis, restoring tracheal architecture, blood vessels, matrix components, pseudostratified columnar and stratified epithelium, ciliary structures, mucin production, and goblet cells. In vitro tests show that the biosynthetic graft can provide the desired axial and flexural stability, and biomechanical function approaching that of native trachea. These results encourage future studies to evaluate safety and efficacy, including biomechanics and collapse risk, biodegradation, and in vivo response enabling a stable long-term tracheal repair option for pediatric patients with LSCTS and other tracheal defects.

Drug delivery systems for wound healing treatment of upper airway injury

INTRODUCTION

Endotracheal intubation is a common procedure to maintain an open airway with risks for traumatic injury. Pathological changes resulting from intubation can cause upper airway complications, including vocal fold scarring, laryngotracheal stenosis, and granulomas and present with symptoms such as dysphonia, dysphagia, and dyspnea. Current intubation-related laryngotracheal injury treatment approaches lack standardized guidelines, relying on individual clinician experience, and surgical and medical interventions have limitations and carry risks.

AREAS COVERED

The clinical and preclinical therapeutics for wound healing in the upper airway are described. This review discusses the current developments on local drug delivery systems in the upper airway utilizing particle-based delivery systems, including nanoparticles and microparticles, and bulk-based delivery systems, encompassing hydrogels and polymer-based approaches.

EXPERT OPINION

Complex laryngotracheal diseases pose challenges for effective treatment, struggling due to the intricate anatomy, limited access, and recurrence. Symptomatic management often requires invasive surgical procedures or medications that are unable to achieve lasting effects. Recent advances in nanotechnology and biocompatible materials provide potential solutions, enabling precise drug delivery, personalization, and extended treatment efficacy. Combining these technologies could lead to groundbreaking treatments for upper airways diseases, significantly improving patients' quality of life. Research and innovation in this field are crucial for further advancements.

Individualized Analysis and Treatment of Difficult Weaning From Ventilation Following Open Cardiac Surgery in Young Children With Congenital Heart Disease

Aims

The study explores the leading causes of postoperative extubation difficulties in pediatric patients (neonates and toddlers) with congenital heart diseases and establishes individualized treatment for different reasons.

Method

We retrospectively analyzed medical records of 4,971 pediatric patients with congenital heart defects treated in three tertiary Congenital Heart Disease Centres in China from January 2005 to December 2020, from whom we selected those with difficulty extubation but successful weaning during the postoperative period. Next, we performed an analysis of risk factors and reported the combined experience of individualized treatment for successful extubation.

Results

Seventy-five pediatric patients were identified in our database, among whom 23 had airway stenosis, 17 had diaphragmatic dysfunction, and 35 had pulmonary infection. The patients were all successfully weaned from the ventilator after an individualized treatment plan. In addition, the intubation time in the airway stenosis group was 17.7 ± 9.0, 33.6 ± 13.9 days in the diaphragmatic dysfunction group, and 11.9 ± 3.8 days in the pulmonary infection group.

Conclusion

Given the primary reasons for difficult weaning following open-heart surgery in pediatric patients with congenital heart diseases, an individualized treatment scheme can achieve the ideal therapeutic effect where patients can be weaned faster with a shorter intubation period.

An Infant With Congenital Tracheal and Bronchial Stenosis Diagnosed by Chest Three-Dimensional Computed Tomography

In this case report, we describe the case of an infant with repeated wheezing diagnosed relatively early with congenital tracheal and bronchial stenosis after evaluation by chest three-dimensional computed tomography (3D-CT). The patient was a six-month-old male infant with a one-month history of cough and wheezing. His symptoms worsened the day before admission, and he was admitted with pneumonia and wheezing. However, wheezing continued after treatment with intravenous steroids and inhalation of a short-acting β2-stimulant. 3D-CT of the chest revealed tracheal stenosis, right bronchial stenosis, and right tracheobronchial bronchus.

The patient was finally diagnosed with congenital tracheal and bronchial stenosis via bronchoscopy. A virtual bronchoscopic navigation image of the tracheal lumen was created based on the CT images. Although virtual bronchoscopic navigation is more difficult for the dynamic evaluation and evaluation of mucosal lesions than bronchoscopy, it has the advantage of not directly invading the airway. Therefore, if a fixed stenotic lesion is suspected at a facility where bronchoscopy is difficult, evaluation using chest 3D-CT and virtual bronchoscopic navigation may be helpful for diagnosis. In conclusion, congenital tracheal/bronchial stenosis should be considered in patients with prolonged wheezing and recurrent airway infections, and evaluation by chest 3D-CT and virtual bronchoscopic navigation may be helpful for diagnosis.

Tracheoplasty for Patients with Pulmonary Artery Sling and Tracheal Stenosis: A Meta-Analysis

We performed this meta-analysis to assess the safety and efficacy of tracheoplasty for patients with pulmonary artery sling (PAS) and tracheal stenosis. Published studies that included surgical treatment of PAS and tracheal stenosis with and without tracheoplasty were identified by searching the PubMed, EMBASE, and Cochrane Library databases until May 2020. The outcomes assessed included postoperative ventilation time, early and late mortality, and follow-up respiratory symptoms. The mean difference (MD)/risk ratio (RR) with 95% confidence intervals (CI) was estimated with a random-effects/fixed-effects model. Subgroup analysis was performed stratified by percentage of patients with tracheal rings. A total of eight studies comprising 219 patients with PAS accompanied by tracheal stenosis were included. The pooled estimates of postoperative ventilation time (MD 17.68, 95% CI 6.38 to 28.98, p < 0.01) and early mortality (RR 3.93, 95% CI 1.55 to 9.95, p < 0.01) favored the repair-only group. Late mortality (RR 1.33, 95% CI 0.48 to 3.68, p = 0.58) and respiratory symptoms (RR 1.51, 95% CI 0.50 to 4.57, p = 0.47) at follow-up showed no significant differences between the groups with repair-only and repair with tracheoplasty. The same results were found in subgroup analyses. For the surgical treatment of PAS with tracheal stenosis, repair without tracheoplasty appears to result in shorter postoperative ventilation time and lower early mortality, with no increase in late mortality or respiratory symptoms at follow-up, compared with concomitant tracheoplasty.

Complete Tracheal Ring Deformity. A Translational Genomics Approach to Pathogenesis

Rationale: Complete tracheal ring deformity (CTRD) is a rare congenital abnormality of unknown etiology characterized by circumferentially continuous or nearly continuous cartilaginous tracheal rings, variable degrees of tracheal stenosis and/or shortening, and/or pulmonary arterial sling anomaly.Objectives: To test the hypothesis that CTRD is caused by inherited or de novo mutations in genes required for normal tracheal development.Methods: CTRD and normal tracheal tissues were examined microscopically to define the tracheal abnormalities present in CTRD. Whole-exome sequencing was performed in children with CTRD and their biological parents ("trio analysis") to identify gene variants in patients with CTRD. Mutations were confirmed by Sanger sequencing, and their potential impact on structure and/or function of encoded proteins was examined using human gene mutation databases. Relevance was further examined by comparison with the effects of targeted deletion of murine homologs important to tracheal development in mice.Measurements and Main Results: The trachealis muscle was absent in all of five patients with CTRD. Exome analysis identified six de novo, three recessive, and multiple compound-heterozygous or rare hemizygous variants in children with CTRD. De novo variants were identified in SHH (Sonic Hedgehog), and inherited variants were identified in HSPG2 (perlecan), ROR2 (receptor tyrosine kinase-like orphan receptor 2), and WLS (Wntless), genes involved in morphogenetic pathways known to mediate tracheoesophageal development in mice.Conclusions: The results of the present study demonstrate that absence of the trachealis muscle is associated with CTRD. Variants predicted to cause disease were identified in genes encoding Hedgehog and Wnt signaling pathway molecules, which are critical to cartilage formation and normal upper airway development in mice.