Enhancing long-segmental tracheal restoration: A self-repairing hydrogel loaded with chondrocytokines for sutureless anastomosis and cartilage regeneration.

Artificial tracheal substitutes encounter significant challenges during long-segmental tracheal defects (LSTD) reconstruction, notably early postoperative anastomotic stenosis and tracheal chondromalacia. Mitigating early anastomotic stenosis by creating a compliant sutureless substitute is pivotal. Enhancing its chondrogenic capacity is equally critical for sustained healthy tracheal cartilage regeneration. This study proposes a self-healing hydrogel for sutureless tracheal anastomosis to mitigate anastomotic stenosis, enriched with kartogenin (KGN) and transforming growth factor-ß1 (TGFß1) to bolster chondrogenic properties. Initially, two precursor solutions were prepared: 1) aldehyde-modified hyaluronic acid with sulfonation and ß-cyclodextrin-CHO loaded with KGN; 2) hydrazide-grafted gelatin loaded with TGFß1. Coextrusion of these solutions resulted in a gelated G + TGFß1/sH-CD + KGN hydrogel, characterized by a robust covalent bonding network of acylhydrazones between hydrazide and aldehyde groups, imparting excellent self-healing properties. The G + TGFß1/sH-CD + KGN hydrogels, showcasing favorable cytocompatibility, excellent injectability, and rapid gelation, were loaded with bone marrow stem cells. These were customized into O-shaped rings and assembled into a malleable tracheal substitute using our established ring-to-tube method. This resultant compliant substitute facilitated sutureless anastomosis of LSTD in a rabbit model, attributed to the Schiff base reaction between the hydrogel's carbonyl group and the tissue's amino group. Notably, the tracheal substitute reduced early postoperative anastomotic stenosis, maintained tracheal patency, alleviated sputum blockage, promoted reepithelization, and increased the survival rate of the experimental rabbits. The sustained release of chondrocytokines resulted in excellent tracheal cartilage regeneration. Employing chondrocytokines-loaded hydrogels with self-healing properties represents a significant advancement in sutureless tracheal anastomosis and tracheal cartilage regeneration, holding promising potential in inhibiting early postoperative anastomotic stenosis and tracheal chondromalacia when treating LSTD.

Revolutionizing tracheal reconstruction: innovations in vascularized composite allograft transplantation.

Tracheal defects, particularly those extending over long segments, present substantial challenges in reconstructive surgery due to complications in vascularization and integration with host tissues. Traditional methods, such as extended tracheostomies and alloplastic stents, often result in significant morbidity due to mucus plugging and mechanical erosion. Recent advances in vascularized composite allograft (VCA) transplantation have opened new avenues for effective tracheal reconstruction. This article reviews the evolution of tracheal reconstruction techniques, focusing on the shift from non-vascularized approaches to innovative revascularization methods that enhance graft integration and functionality. Key advancements include indirect revascularization techniques and the integration of regenerative medicine, which have shown promise in overcoming historical barriers to successful tracheal transplantation. Clinical case studies are presented to illustrate the complexities and outcomes of recent tracheal transplantation procedures, highlighting the potential for long-term success through the integration of advanced vascular engineering and immune modulation strategies. Furthermore, the role of chimerism in reducing graft rejection and the implications for future tracheal transplantation and tissue engineering efforts are discussed. This review underscores the transformative potential of VCA in tracheal reconstruction, paving the way for more reliable and effective treatments for extensive tracheal defects.

Analysis of preoperative and postoperative blood gas indices and airflow dynamics with tracheal stenosis undergoing tracheal reconstruction.

Prolonged ventilation remains the most common cause of tracheal stenosis. Tracheal reconstruction is the gold standard treatment in these cases. The success of surgery is based on results of the pulmonary function test (PFT) which relies on patients' performance and their cooperation. The objective of the study was to investigate the impact of tracheal reconstruction in cases of tracheal stenosis on blood gas indices as well as airflow indices and whether arterial blood gas (ABG) can be a better surrogate of adequacy of tracheal reconstruction. This was a retrospective observational study of 61 patients with tracheal stenosis between the ages of 21 and 65 years who underwent tracheal reconstruction. The preoperative and postoperative values of various blood gas indices like partial pressure of oxygen (pO2), partial pressure of carbon dioxide (pCO2), and potential of hydrogen (pH) and airflow indices like forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF) were evaluated and found that all the parameters showed significant improvement after tracheal reconstruction with P < 0.0001. Tracheal reconstruction resulted in improvement of oxygenation and airflow parameters which led to relief of symptoms. Hence, ABG can be used as a surrogate marker for denoting the success of the surgery.

Spinal cord ischemia following laryngotracheal reconstruction surgery: a case report.

We present a 20-year-old patient with subglottic and tracheal stenosis was taken for a tracheal resection and end-to-end anastomosis. The patient's neck was positioned in hyperflexion using chin stitches to minimize tension at the anastomosis. On post-operative period, the patient developed paresthesias in upper and lower extremities associated with motor weakness. Magnetic resonance imaging was performed showing lesions compromising ventral spinal cord at the level of C4-C5 and C6-C7. Chin stitches were removed and neck flexion was reduced. The patient remained in the intensive care unit with vasopressors, physical therapy and intravenous fluid-therapy to maintain mean arterial pressure above 90 mmHg. After 3 weeks, the patient was discharged with no neurologic deficit. There are few cases reported of acute ischemic spinal injury following tracheal reconstruction. If this complication arises, neck posture should be corrected, maintenance of MAP above 90 mmHg and implementation of early physical therapy is key to improve neurologic outcomes.

The internal mammary artery perforator flap in pharyngoesophageal, cervical tracheal, and cutaneous neck reconstruction.

The internal mammary artery perforator (IMAP) flap is an evolution of the deltopectoral flap that is harvested based upon a single perforator from the internal mammary artery. Its favorable characteristics include pliability as a fasciocutaneous flap, ease of harvest, and minimal donor site morbidity. In this paper, we report our harvest technique and the versatility of the IMAP flap for pharyngoesophageal, cervical tracheal, and cutaneous neck defects. We seek to highlight the IMAP as a useful regional reconstructive option in both the primary and salvage reconstructive setting. As such, this flap is an important option in the head and neck reconstructive surgeon's armamentarium.

Case Report: ECMO-assisted tracheal reconstruction in a 30-week-gestation preterm infant with tracheal stenosis.

Tracheal stenosis is a rare but life-threatening disease in preterm infants. Misdiagnosis as congenital tracheal stenosis is common, making surgical management challenging. This report presents a case of a preterm infant with tracheal stenosis and congenital heart malformation treated with ECMO-assisted tracheal resection and end-to-end anastomosis. A male infant was born at 30 weeks of gestation with severe asphyxia, cardiac insufficiency, and pneumonia. Following failed medical treatment, fiberoptic bronchoscopy confirmed mid-tracheal to carinal stenosis. After a 2-week treatment course, ECMO-assisted tracheal resection and end-to-end anastomosis were performed successfully. This case confirms the feasibility of tracheal resection and end-to-end anastomosis in low-weight, preterm infants with tracheal stenosis born at 30 weeks gestation. The utilization of ECMO for oxygenation during surgery provides a clear surgical field and shorter operating time. Surgical intervention may be necessary for neonatal tracheal stenosis depending on the clinical presentation.

Stented cryopreserved aortic allograft for reconstruction of long-segment post-tuberculosis tracheal stenosis.

Tracheobronchial tuberculosis is one of the conditions causing long segment tracheal stenosis and is a clinically challenging scenario. This report describes a successful tracheal reconstruction in a 44-year-old man with long-segment post-tuberculosis tracheobronchial stenosis, utilizing a stented cryopreserved aortic allograft. The procedure was necessitated by the failure of conventional treatments. The stenotic segment was resected and replaced with a cryopreserved aortic allograft, supported by a metallic stent to maintain airway patency. Post-surgery, the patient experienced resolution of dyspnea without major complications. Currently, at 33 months post-operation, the patient enjoys an enhanced quality of life with effective breathing, speaking, swallowing abilities, and has resumed normal daily activities, with regular bronchoscopic follow-ups. This report demonstrates a novel approach for managing challenging tuberculosis-induced long segment airway stenosis.

Flap-based Closure of Acquired Tracheoesophageal Fistulas.

Iatrogenic tracheoesophageal fistulae management and repair are difficult to manage with few resourced describing management and repair. Two cases are presented describing the approach to and repair of a tracheoesophagea fistula; one with a free flap and one with local flap reconstruction. Both cases utilized allograft material to maintain separation between the alimentary and repiratory tracts. Laryngoscope, 134:3761-3764, 2024.

Vascularized tracheal substitutes constructed by exosome-load hydrogel-modified 3D printed scaffolds / 中国组织工程研究

BACKGROUND:For the replacement treatment of long-segment tracheal defects,although tissue engineering research has made some progress in recent years,it is still not perfect,and one of the biggest difficulties is that the hemodynamic reconstruction of the tracheal replacement cannot be achieved rapidly. OBJECTIVE:To preliminarily explore the potential of polycaprolactone scaffolds modified with exosome-loaded hydrogels to construct a rapidly vascularized tracheal substitute. METHODS:Exosomes were extracted from bone marrow mesenchymal stem cells of SD rats.After preparation of hyaluronic acid methacrylate solution,the exosome solution was mixed with hyaluronic acid methacrylate solution at a volume ratio of 1:1.Hyaluronic acid methacrylate hydrogels loaded with exosomes were prepared under ultraviolet irradiation for 5 minutes.The degradation of exosome-unloaded hydrogels and the controlled release of exosome-loaded hydrogels were detected.Polycaprolactone scaffolds were prepared by 3D printing.The pure hyaluronic acid methacrylate solution and the exosome-loaded hyaluronic acid methacrylate solution were respectively added to the surface of the scaffold.Hydrogel-modified scaffolds and exosome-modified scaffolds were obtained after ultraviolet irradiation.Thirty SD rats were randomly divided into three groups with 10 rats in each group and subcutaneously implanted with simple scaffolds,hydrogel-modified scaffolds and exosome-modified scaffolds,respectively.At 30 days after surgery,the scaffolds and surrounding tissues of each group were removed.Neovascularization was observed by hematoxylin-eosin staining and Masson staining and the expression of CD31 was detected by immunofluorescence. RESULTS AND CONCLUSION:(1)As time went by,the hydrogel degraded gradually,and the exosomes enclosed in the hydrogel were gradually released,which could be sustained for more than 30 days.The exosome release rate was faster than the degradation rate of the hydrogel itself,and nearly 20%of the exosomes were still not released after 30 days of soaking.(2)Under a scanning electron microscope,the surface of the simple polycaprolactone scaffold was rough.After hydrogel modification,a layer of gel was covered between the pores of the scaffold,and the scaffold surface became smooth and dense.(3)After 30 days of subcutaneous embedding,hematoxylin-eosin staining and Masson staining showed that more neovascularization was observed inside the scaffolds of the exosome-modified scaffold group compared with the hydrogel-modified scaffold group.The hydrogels on the scaffolds of the two groups were not completely degraded.Immunofluorescence staining showed that CD31 expression in the exosome-modified scaffold group was higher than that in the hydrogel-modified scaffold group(P<0.000 1).(4)These results indicate that hyaluronic acid methacrylate hydrogels can be used as controlled-release carriers for exosomes.The 3D-printed polycaprolactone scaffold modified by hyaluronic acid methacrylate hydrogel loaded with exosomes has good biocompatibility and has the potential to promote the formation of neovascularization.

A cell-free tissue-engineered tracheal substitute with sequential cytokine release maintained airway opening in a rabbit tracheal full circumferential defect model.

In this study, a cell-free tissue-engineered tracheal substitute was developed, which is based on a 3D-printed polycaprolactone scaffold coated with a gelatin-methacryloyl (GelMA) hydrogel, with transforming growth factor-ß1 (TGF-ß) and stromal cell-derived factor-1α (SDF-1) sequentially embedded, to facilitate cell recruitment and differentiation toward chondrocyte-phenotype. TGF-ß was loaded onto polydopamine particles, and then encapsulated into the GelMA together with SDF-1, and called G/S/P@T, which was used to coat 3D-printed PCL scaffold to form the tracheal substitute. A rapid release of SDF-1 was observed during the first week, followed by a slow and sustained release of TGF-ß for approximately four weeks. The tracheal substitute significantly promoted the recruitment of mesenchymal stromal cells (MSCs) or human bronchial epithelial cells in vitro, and enhanced the ability of MSCs to differentiate towards chondrocyte phenotype. Implantation of the tissue-engineered tracheal substitute with a rabbit tracheal anterior defect model improved regeneration of airway epithelium, recruitment of endogenous MSCs and expression of markers of chondrocytes at the tracheal defect site. Moreover, the tracheal substitute maintained airway opening for 4 weeks in a tracheal full circumferential defect model with airway epithelium coverage at the defect sites without granulation tissue accumulation in the tracheal lumen or underneath. The promising results suggest that this simple, cell-free tissue-engineered tracheal substitute can be used directly after tracheal defect removal and should be further developed towards clinical application.

Complications associated with costal cartilage harvest in pediatric laryngotracheal reconstruction.

Objective: We aimed to determine the rate of complications associated with autologous costal cartilage graft harvest for pediatric laryngotracheal reconstruction (LTR). Secondarily, we sought to identify risk factors associated with the harvest of autologous costal cartilage, as well as evaluate management strategies. Data Sources: An electronic database search of Ovid MEDLINE, Ovid EMBASE, and PubMed was completed for articles pertaining to complications in autologous costal cartilage harvest for pediatric LTR. Review Methods: This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The study characteristics, operative information, and patient demographics were collected. The data concerning postoperative complications, risk factors, and management strategies were collected and analyzed for patterns. Results: A total of 31 manuscripts representing 745 patients were included for analysis. The reported donor site complications included pneumothorax (n = 13, 1.74%), pleural tear (n = 5, 0.67%), infection (n = 8, 1.07%), and scar-related problems (n = 2, 0.26%). There were no reported cases of seroma, persistent pain, or chest wall deformity. Only five studies discussed the management of donor site complications, with intervention in 11 (39.28%) patients including chest tube drainage and steroid injection. Conclusion: There is significant variability in the literature regarding complication rates in autologous costal cartilage harvest for pediatric LTR. The incidence of major postoperative complications is low and supports the use of autologous costal cartilage as graft material for pediatric LTR. Level of Evidence: NA.

A novel classification of tracheal defects and the reconstruction strategies: A retrospective study based on 106 cases.

Objective: The study aims to present a novel classification of tracheal defects and the corresponding reconstruction strategies. Methods: The retrospective study was designed to analyze patients with diagnosed primary or secondary tracheal tumors from 1991 to 2020. Surgical techniques, complications and prognosis were reviewed. Airway status and patient outcomes were the principal follow-up measures. Tracheal defects were classified into two plane sizes (vertical (V) and horizontal (H) planes). Vertical defects were further categorized into three groups based on their tracheal ring numbers (V1, ≤ 5 rings; V2, 6-10 rings; and V3, > 10 rings). Tracheal defects with horizontal plane size H1 and H2 represent defects less and more than one-half the circumference of trachea. Thus, suitable reconstruction strategies were planned primarily based on "V" and "H" classifications. The reconstruction strategies performed were sleeve resection followed by an end-to-end anastomosis, window resection with sternocleidomastoid myoperiosteal flap reconstruction, defects conversion with rotation anastomosis, and modified tracheostomy with secondary flap reconstruction. Results: A total of 106 patients diagnosed with tracheal defects were enrolled in the study, of whom 59 patients underwent sleeve resection followed by end-to-end anastomosis; 40 patients received window resection alongside sternocleidomastoid (SCM) myoperiosteal flap reconstruction; five patients received converting defects with rotation anastomosis and two patients underwent modified tracheostomy with secondary stage flap reconstruction. Lumen stenosis occurred in three V2H1 defect cases and were treated by a second reconstruction surgery. Iatrogenic unilateral recurrent laryngeal nerve paralysis occurred in two patients with the V3H2 defect type, who were treated by temporary tracheotomy and partial vocal cord resection and extubated successfully during follow-up. All 106 patients achieved airway patency with adequate laryngeal function at the end of follow-up. No anastomotic dehiscence or bleeding occurred in any patient postoperatively. Conclusion: Though a significant number of multicenter studies concerning the reconstruction and classification of tracheal defects are needed, the study herein provides a novel classification of tracheal defects, which is primarily developed on the defect size. Therefore, the study might serve as a potential source for identifying suitable reconstruction strategies for practitioners.

Application of aortic allograft in trachea transplantation.

BACKGROUND: The use of tracheal implants for tracheal reconstruction remains a challenge in thoracic medicine due to the complex structure of the trachea in mammalian organisms, including smooth muscles, cartilage, mucosa, blood vessels, cilia, and other tissues, and the difficulty in achieving tracheal regeneration using implants from either allografts or synthetic biomaterials. METHODS: This project used the Lee-Sung strain pig, a swine breed local to Taiwan, as the experimental subject. The aorta of the pig was harvested, decellularized to form the scaffold, and transplanted into the trachea of allogeneic pigs together with growth factors. Postoperative physiological function and tissue changes were observed. The postoperative physiological parameters of the LSP were monitored, and they were sacrificed after a certain period to observe the pathological changes in the tracheal epithelial cells and cartilages. RESULTS: Overall, six LSP tracheal transplantations were performed between March 4, 2020, and March 10, 2021. These included aortic patch anastomosis for pig 1 and aortic segmental anastomosis for pigs 2-6. The shortest and longest survival periods were 1 day and 147 days, respectively. Excluding the pig that survived for only 1 day due to a ruptured graft anastomosis, all other subjects survived for over 1 month on average. CONCLUSION: In this study, we grafted a decellularized porcine aorta into a recipient pig with a tracheal defect. We found cryopreservation of the allogeneic aorta transplantation was a feasible and safe method for the management of airway disease, and immunosuppressants were unnecessary during the treatment course.

Case Report: Defect repair post-resection of cervical tracheal granular cell tumor by cervical anterior banded myofascial flap: A case study and literature review.

Objective: A case of cervical tracheal granular cell tumor (CTGCT) is reported together with a discussion on the clinical manifestation, diagnosis, and treatment of CTGCT. Additional cases of tumors in the tracheal membrane are also discussed. A simple and viable tracheal reconstruction method was proposed. The research design involves a case report and literature review. Methods: Twenty-four case reports on cervical GCT with complete clinical data were identified, with a specific focus on cases involving surgical treatment of tumors in the cervical tracheal membrane. Results: Twenty-eight reports of GCT in the cervical trachea and six reports on cervical tracheal membrane tumors were identified. The clinical data of a middle-aged Asian woman with a cervical GCT was also discussed. Conclusion: Cervical GCT is a rare disease, and tracheal resection is a reasonable treatment for cervical tracheal GCT. The proposed procedure is a simple and feasible method for reconstruction of the cervical tracheal membrane defect using a double-pedicled banded myofascial flap.

Achieving Successful Extubation and Cost-Effective Recovery Following Anesthetic Airway Management in Supracarinal Tracheal Reconstruction Surgeries: A Retrospective Analysis.

Introduction From an anesthesiologist's perspective, perioperative concerns related to supracarinal tracheal reconstruction surgery include having uninterrupted smooth ventilation without any laryngeal edema, glottic dysfunction, and airway leak. Surgical concerns comprise various kinds of anastomotic dissections, fistulas to innominate arteries, and the esophagus. The most serious complication following tracheal surgery is anastomotic separation, which might manifest modestly as stridor, respiratory distress, and extremis. To avoid dire repercussions, prompt management and securing the airway are necessary. Against this background, we wanted to highlight the importance of early extubation and discharge of supracarinal tracheal reconstruction patients from hospitals without any postoperative complications and with the least expenses possible, since most of these patients have already undergone postintubation tracheal stenosis and prolonged intensive care unit stay, and have experienced significant financial burden incurring from preceding events. Methodology Medical records of all patients admitted for tracheal reconstruction during the period from March 2019 to April 2022 (four years) were reviewed to collect patient demographic details, surgical descriptions, anesthesia data, records of pre-anesthetic evaluations, and postoperative details up until the hospital discharge. Results The most common reason for tracheal stenosis among our patients was post-intubation tracheal stenosis (PITS), which was seen in 8/13 patients (61.53%); 4/13 patients (30.76%) had stridor at rest and underwent emergency tracheostomy preoperatively immediately following admission to the hospital. The stenosis was situated at a median distance of 3 cm [interquartile range (IQR): 0.5-7] from the true vocal cords or 7 cm (IQR: 3-9) from the carina. The median length of tracheal resection was 2 cm (IQR: 1-4). We observed that the mode of induction for airway management was tracheostomy tube in four patients (with 90% tracheal stenosis), placement of laryngeal mask airway (LMA) with spontaneous ventilation in four patients (with 75% tracheal stenosis), and small-size (#5-7.5 sizes) endotracheal tube (ETT) placement in five patients (with less than 75% tracheal stenosis). The postoperative complication noted was bleeding from the operative site in 1/13 patients (7.6%); a 0% mortality rate was noted during the hospital stay and up until six months post-discharge. We noted that the median duration of postoperative hospitalization was five days (IQR: 2-15), and the total cost incurred by each patient was less than INR 85,000 (USD 1,000). Conclusion Our analysis revealed that all our patients were extubated in the operative room and shifted to the ward. In the "open airway phase", standard distal tracheal intubation and cross-field ventilation techniques, and tracheal suturing were facilitated by the apnoea-ventilation-apnoea technique. Both the techniques along with the emergency tracheostomies done in severe tracheal obstruction preoperatively and intraoperative anesthesia management with the insertion of LMA Supreme, maintained with spontaneous breathing techniques, offered potential advantages in the management of supracarinal tracheal reconstruction surgeries. The multidisciplinary teamwork along with close communication and good rapport with the surgical team was found to be the key factor in the fast-track extubation and recovery of these patients.

Tracheal reconstruction surgery for congenital tracheal stenosis.

PURPOSE: Congenital tracheal stenosis is a rare but dangerous disease. Reconstructive tracheal surgery is a life-saving treatment but also a challenging procedure. This study aims to evaluate the outcomes of tracheal reconstruction surgery. METHODS: A prospective cohort study was conducted with all the records of congenital tracheal stenosis which had been managed by tracheal reconstruction surgery at Children's Hospital 2 Ho Chi Minh City from August 2013 to August 2022. RESULTS: Sixty-seven cases, who underwent slide tracheoplasty, were included in our study. Mean age was 7.6 months (25 days - 8 years). Common congenital-associated lesion was left pulmonary artery sling, accounting for 65.7% of cases. Bronchial stenosis was found in 22.4% patients. Emergency surgery was performed in eight cases. The survival rate in this review was 86.6%. Nine patients died in which four of nine cases (44.4%) were emergency surgery. The recurrent stenosis rate was 8.9%, only two cases needed reoperation in which one died and one recovered uneventfully. The outcomes of surgery were good in 53 cases (79.1%). CONCLUSION: Tracheal reconstruction surgery with slide tracheoplasty technique is safe and versatile technique which is feasible in every case of congenital tracheal stenosis. Mortality was associated with severe cases which required emergency surgery.

Scaffold-Free Tracheal Engineering via a Modular Strategy Based on Cartilage and Epithelium Sheets.

Tracheal defects lead to devastating problems, and practical clinical substitutes that have complex functional structures and can avoid adverse influences from exogenous bioscaffolds are lacking. Herein, a modular strategy for scaffold-free tracheal engineering is developed. A cartilage sheet (Cart-S) prepared by high-density culture is laminated and reshaped to construct a cartilage tube as the main load-bearing structure in which the chondrocytes exhibit a stable phenotype and secreted considerable cartilage-specific matrix, presenting a native-like grid arrangement. To further build a tracheal epithelial barrier, a temperature-sensitive technique is used to construct the monolayer epithelium sheet (Epi-S), in which the airway epithelial cells present integrated tight junctions, good transepithelial electrical resistance, and favorable ciliary differentiation capability. Epi-S can be integrally transferred to inner wall of cartilage tube, forming a scaffold-free complex tracheal substitute (SC-trachea). Interestingly, when Epi-S is attached to the cartilage surface, epithelium-specific gene expression is significantly enhanced. SC-trachea establishes abundant blood supply via heterotopic vascularization and then is pedicle transplanted for tracheal reconstruction, achieving 83.3% survival outcomes in rabbit models. Notably, the scaffold-free engineered trachea simultaneously satisfies sufficient mechanical properties and barrier function due to its matrix-rich cartilage structure and well-differentiated ciliated epithelium, demonstrating great clinical potential for long-segmental tracheal reconstruction.

Sleeve resection with end-to-end anastomosis in the reconstruction of tracheal defects exceeding six rings: a clinical feasibility study and safety assessment.

Objectives: Reconstruction is always required for tracheal defects and sleeve resection with end-to-end anastomosis is the most common used. The aim of the study was to present surgical techniques and evaluate the outcomes of sleeve resection with end-to-end anastomosis in the reconstruction of tracheal defects exceeding six rings. Methods: The study included patients with primary or secondary malignancies and tracheal stenosis from 2014 to 2019, who were treated with sleeve resection exceeding six tracheal rings, and reconstructed with end-to-end anastomosis. Airway status and patient outcomes were the principal follow-up measures. Results: A total of 16 patients were enrolled in the study including three primary tracheal malignancies, 12 invasive thyroid carcinomas and one with tracheal stenosis. The extent of tracheal resection ranged from seven to nine rings, and the primary end-to-end anastomosis was performed in all 16 patients. Performance of tracheostomy or cricothyroidotomy was done in 6 patients with decannulation at a median of 42 days (range, 28-56). No anastomotic dehiscence, infection or bleeding occurred postoperatively, and all 16 patients maintained an unobstructed airway through the end of follow-up. Conclusions: Sleeve resection reconstructed with end-to-end anastomosis can serve as an appropriate therapeutic strategy for the tracheal defects even exceeding six rings. Adequate laryngeal release is the key to surgical success.

Surgical Innovations in Tracheal Reconstruction: A Review on Synthetic Material Fabrication.

Background and Objectives: The aim of this review is to explore the recent surgical innovations in tracheal reconstruction by evaluating the uses of synthetic material fabrication when dealing with tracheomalacia or stenotic pathologies, then discussing the challenges holding back these innovations. Materials and Methods: A targeted non-systematic review of published literature relating to tracheal reconstruction was performed within the PubMed database to help identify how synthetic materials are utilised to innovate tracheal reconstruction. Results: The advancements in 3D printing to aid synthetic material fabrication have unveiled promising alternatives to conventional approaches. Achieving successful tracheal reconstruction through this technology demands that the 3D models exhibit biocompatibility with neighbouring tracheal elements by encompassing vasculature, chondral foundation, and immunocompatibility. Tracheal reconstruction has employed grafts and scaffolds, showing a promising beginning in vivo. Concurrently, the integration of resorbable models and stem cell therapy serves to underscore their viability and application in the context of tracheal pathologies. Despite this, certain barriers hinder its advancement in surgery. The intricate tracheal structure has posed a challenge for researchers seeking novel approaches to support its growth and regeneration. Conclusions: The potential of synthetic material fabrication has shown promising outcomes in initial studies involving smaller animals. Yet, to fully realise the applicability of these innovative developments, research must progress toward clinical trials. These trials would ascertain the anatomical and physiological effects on the human body, enabling a thorough evaluation of post-operative outcomes and any potential complications linked to the materials or cells implanted in the trachea.