Tracheal Tumors: Clinical Practice Guidelines for Palliative Treatment and Follow-Up.

A substantial portion of patients with advanced cancer cannot be cured, regardless of the therapeutic methods employed. Hence, rational palliative causal treatment becomes crucial. Representative studies specifically addressing the exclusive palliative treatment of patients diagnosed with tracheal cancers have not been identified. In most studies, patients treated palliatively constituted a subset of the overall evaluated group. A thorough literature review was conducted, focusing on three types of palliative treatment: palliative radiotherapy, palliative surgical procedures, and systemic treatment for advanced disease. This review uniquely fills a significant gap in the existing literature by providing the first comprehensive and updated clinical practice guidelines specifically focused on the palliative treatment of tracheal tumors. The proposed guidelines emphasize the unique clinical challenges and treatment strategies pertinent to palliative care in tracheal tumors, which are not adequately covered in existing guidelines for other thoracic malignancies.

Evaluating the Accuracy of Chest CT in Detecting COVID-19 Through Tracheobronchial Wall Thickness: Insights From Emergency Department Patients in Mid-2023.

Background The post-pandemic phase of the coronavirus infectious disease that emerged in 2019 (COVID-19) has necessitated updates in radiology, with emerging evidence suggesting tracheobronchial wall thickness as a potential new diagnostic marker. Purpose To evaluate the accuracy of chest computed tomography (CT) scans in identifying COVID-19 by assessing tracheobronchial wall thickness in mid-2023. Material and methods A retrospective review was conducted on 60 patients who underwent thoracoabdominal CT and the severe acute respiratory syndrome coronavirus (SARS-CoV-2) antigen tests during emergency visits between June and August 2023. Tracheobronchial wall thickness was measured using a 4-point scale (1=no thickening, 2=mild, 3=moderate, 4=significant). Lung assessment employed the COVID-19 Reporting and Data System (CO-RADS). Patients were classified based on antigen test results. The Mann-Whitney U test and Fisher's exact test compared characteristics and CT findings. Diagnostic performance was evaluated using the area under the receiver operating characteristic curves (AUC). Results The SARS-CoV-2-positive group showed significantly thicker tracheobronchial walls (median 1.5 mm vs. 1.2 mm, P < 0.001), especially in the trachea's membranous wall (median 1.2 mm vs. 0.9 mm, P < 0.001) and higher scores (median 3 vs. 2, P < 0.001). CO-RADS scores showed no significant difference. Quantitative and qualitative wall thickness assessments demonstrated high diagnostic value, with AUCs of 0.90 and 0.94, and accuracies of 85% and 87%, respectively. Conclusion Tracheobronchial wall thickness on chest CT exhibited high diagnostic accuracy, establishing it as a reliable marker for COVID-19 detection in mid-2023.

Approaching Saber-Sheath Trachea in a Patient with Bilateral Vocal Cord Abductor Palsy and Post Tracheostomy Tracheal Stenosis.

Human trachea has variable shapes and the most common are circular and oval-shaped. Other shapes are rare to find and usually related to some diseases. Such as the Saber-sheath shaped trachea, which was commonly attributed to patients with chronic obstructive pulmonary disease (COPD). This case is about a patient who was detected to have dual pathology, bilateral vocal cord abductor palsy, and post-tracheostomy complicated with tracheal stenosis for 40 years. Symptoms worsened in the last three years until he was admitted to the ward. However, upon managing this case with multilevel airway obstruction, we have found out that this patient who did not have COPD, has a Saber-sheath trachea shape. This finding may indicate that the shape is not limited to a certain disease only.

Abstracts of the Italian Society of Thoracic Endoscopy (SIET) 2024 Annual Congress.

We are pleased to introduce the abstracts of the XXIII National Congress of the Italian Society of Thoracic Endoscopy (SIET), which will be held in Florence from 17 to 19 October 2024. The principal objectives of SIET are to (1) Promote research and innovation in the fields of thoracic surgery and endoscopy, facilitating the development and implementation of innovative techniques and technologies; (2) Provide education and training for surgeons, endoscopists, pulmonologists and other related specialties; and (3) Facilitate the exchange of knowledge with the aim of creating a cohesive and active scientific community. The Congress will address the integration of traditional surgical and endoscopic techniques with emerging technologies, with the goal of promoting innovation and education among professionals. The theme of integration will be explored throughout the programme, with a particular focus on the collaborative efforts of different medical specialties to improve patient outcomes. This event will host a multidisciplinary cohort comprising thoracic surgeons, endoscopists, pulmonologists, oncologists, pathologists, radiologists and anaesthetists, who will assume a pivotal role in the multidisciplinary sessions of the scientific programme. The Congress will include several core areas of expertise, including lung cancer, interventional endoscopy, pathology, and upper airway reconstruction. Emphasis will be placed on both the theoretical aspects of these subjects and their practical applications in patient care. The theme of integration will be explored throughout the programme, with particular attention on the impact of recent technological developments in the fields of thoracic surgery and endoscopy. Additionally, the Congress will examine the contributions of allied health professionals, including nurses, physiotherapists, and speech pathologists, to patient care.

The Drosophila tracheal terminal cell as a model for branching morphogenesis.

The terminal cells of the Drosophila larval tracheal system are perhaps the simplest delivery networks, providing an analogue for mammalian vascular growth and function in a system with many fewer components. These cells are a prime example of single-cell morphogenesis, branching significantly over time to adapt to the needs of the growing tissue they supply. While the genetic mechanisms governing local branching decisions have been studied extensively, an understanding of the emergence of a global network architecture is still lacking. Mapping out the full network architecture of populations of terminal cells at different developmental times of Drosophila larvae, we find that cell growth follows scaling laws relating the total edge length, supply area, and branch density. Using time-lapse imaging of individual terminal cells, we identify that the cells grow in three ways: by extending branches, by the side budding of new branches, and by internally growing existing branches. A generative model based on these modes of growth recapitulates statistical properties of the terminal cell network data. These results suggest that the scaling laws arise from the coupled contributions of branching and internal growth. This study establishes the terminal cell as a uniquely tractable model system for further studies of transportation and distribution networks.

Achieving normal pulmonary function following tracheoplasty in infancy.

Infant long-segment congenital tracheal stenosis (LTS) is rare and presents a challenging clinical scenario. We describe the management of a child who required extracorporeal membrane oxygenation following a respiratory arrest and underwent slide tracheoplasty in infancy for severe LTS and required repeated bronchoscopic reinterventions for recurrent tracheal granulations. At 9 years of age, the child has normal pulmonary function testing and a normal exercise tolerance.

Tracheal Ultrasound for Diagnosis of Tracheal Cartilaginous Sleeve in Patients with Syndromic Craniosynostosis.

OBJECTIVE: The aim of this study was to assess the utility of ultrasound (US) imaging for diagnosis of abnormal tracheal morphology, such as tracheal cartilaginous sleeves (TCS), in patients with syndromic craniosynostosis (SC). STUDY DESIGN: Age-matched cohort study. SETTING: Tertiary pediatric hospital. METHODS: Two age-matched cohorts were identified: patients with SC and known TCS based upon airway endoscopy and normal controls without tracheal pathology. Enrolled patients underwent awake US of the neck which were randomized and reviewed by blinded pediatric radiologists and rated on presence or absence of normal tracheal cartilage morphology and visualization or nonvisualization of a tracheostomy tube. Fisher's exact test was used to assess pooled data. Fleiss' Kappa (κ) was calculated to assess inter-rater reliability. RESULTS: Ten patients were included in each cohort. Control patients were gender and age-matched to TCS patients with a mean difference of 3.7 months (±3.9 months). Across all raters, cartilage type was correctly identified in 93% (95% confidence interval [CI]: 84%-98%) and tracheostomy visualization in 97% (95% CI: 89%-99%). The sensitivity and specificity for detection of abnormal cartilage pathology was 87% and 100%, respectively. Inter-rater reliability for cartilage assessment was κ = 0.88 (95% CI: 0.67-1.00, P < .05) and 0.83 (95% CI: 0.58-1.00, P < .05) for tracheostomy presence. CONCLUSION: This study demonstrated that tracheal US is a feasible, accurate screening tool for TCS, and can be successfully performed non-sedated in patients up to 18 years of age, both with and without tracheostomy tubes in place.

Adenoid cystic carcinoma of trachea mimicking a thyroid follicular tumor: A case report and literature review.

Cervical tracheal adenoid cystic carcinoma (TACC) invading the thyroid gland is very rare and easily misdiagnosed as thyroid tumor, this paper reports a TACC invading thyroid in a 33-year-old woman who had been diagnosed as a thyroid follicular tumor in right lobe of thyroid by sonography and ultrasound guided fine needle aspiration in other hospital. She accepted surgical treatment in our hospital and was diagnosed as TACC by pathology, locally involving the thyroid. This paper presents the patient's clinical data, imaging findings, pathological diagnosis, treatment process and reviews the literature of TACC mimicking a thyroid tumor.

Tracheobronchoplasty for severe tracheobronchomalacia: a case-series of patients with acute and chronic critical comorbidities.

OBJECTIVES: There are little data within the literature regarding tracheobronchoplasty in the setting of the acute and chronically ill, morbidly obese or ventilator-dependent patients with tracheobronchomalacia. Short- and long-term outcomes are studied. METHODS: The series represents 12 tracheobronchomalacia patients with American Society of Anesthesiologists (ASA) physical status scores of 3-5. Candidacy was based on bronchoscopic findings during spontaneous respirations with >90% collapse of the trachea and both mainstem bronchi. We used dynamic computed tomography scan as an adjunct in those not mechanically ventilated. Our operative approach was a complete portal robotic approach for those outpatients (wheelchair dependent) and right thoracotomy for those who were already mechanically ventilated with 100% fraction of inspired oxygen with high pressure. Extracorporeal support was used in 2 patients. RESULTS: Patients who underwent robotic repair were discharged without complications. Two patients who were critically ill and required extracorporeal support for their surgeries were separated from extracorporeal membrane oxygenation on postoperative day 2. Three patients died at the follow-up. In 1 patient, the prolene mesh migrated into trachea and caused obstruction of the trachea and required removal with endobronchial techniques. CONCLUSIONS: The repair of tracheobronchomalacia in patients with multiple comorbidities and with severe life-threatening problems in or outside the intensive care unit may have improvement due to the ability to wean from positive pressure ventilation. Surgical technique and the utilization of mesh support in tracheobronchoplasty operations may need to be debated due to duration of the surgery in patients with severe comorbidities.

Establishing Benchmarks for Airway Replacement: Long-Term Outcomes of Tracheal Autografts in a Large Animal Model.

OBJECTIVE: Airway replacement is a challenging surgical intervention and remains an unmet clinical need. Due to the risk of airway stenosis, anastomotic separation, poor vascularization, and necrosis, it is necessary to establish the gold-standard outcomes of tracheal replacement. In this study, we use a large animal autograft model to assess long-term outcomes following tracheal replacement. METHODS: Four New Zealand White rabbits underwent tracheal autograft surgery and were observed for 6 months. Clinical and radiographic surveillance were recorded, and grafts were analyzed histologically and radiographically at endpoint. RESULTS: All animals survived to the endpoint with minimal respiratory symptoms and normal growth rates. No complications were observed. Computed tomography scans of the post-surgical airway demonstrated graft patency at all time points. Histological sections showed no sign of stenosis or necrosis with preservation of the native structure of the trachea. CONCLUSION: We established benchmarks for airway replacement. Our findings suggest that a rabbit model of tracheal autograft with direct reimplantation is feasible and does not result in graft stenosis or airway collapse.

Genetic characterisation of candidate ecdysteroid kinases in Drosophila melanogaster.

Ecdysteroids are major hormones in insects and control moulting, growth, reproduction, physiology, and behaviour. The biosynthesis of ecdysteroids such as 20-hydroxyecdysone (20E) from dietary sterols is well characterised, but ecdysteroid catabolism is poorly understood. Ecdysteroid kinases (EcKs) mediate the reversible phosphorylation of ecdysteroids, which has been implicated in ecdysteroid recycling during embryogenesis and reproduction in various insects. However, to date only two EcK-encoding genes have been identified, in the silkworm Bombyx mori and the mosquito Anopheles gambiae. Previously, we identified two ecdysteroid kinase-like (EcKL) genes-Wallflower (Wall) and Pinkman (pkm)-in the model fruit fly Drosophila melanogaster that are orthologs of the ecdysteroid 22-kinase gene BmEc22K. Here, using gene knockdown, knockout and misexpression, we explore Wall and pkm's possible functions and genetically test the hypothesis that they encode EcKs. Wall and pkm null mutants are viable and fertile, suggesting they are not essential for development or reproduction, whereas phenotypes arising from RNAi and somatic CRISPR appear to derive from off-target effects or other artefacts. However, misexpression of Wall results in dramatic phenotypes, including developmental arrest, and defects in trachea, cuticle and pigmentation. Wall misexpression fails to phenocopy irreversible ecdysteroid catabolism through misexpression of Cyp18a1, suggesting Wall does not directly inactivate 20E. Additionally, Wall misexpression phenotypes are not attenuated in Cyp18a1 mutants, strongly suggesting Wall is not an ecdysteroid 26-kinase. We hypothesise that the substrate of Wall in this misexpression experiment and possibly generally is an unknown, atypical ecdysteroid that plays essential roles in Drosophila development, and may highlight aspects of insect endocrinology that are as-yet uncharacterised. We also provide preliminary evidence that CG5644 encodes an ecdysteroid 22-kinase conserved across Diptera.

Favour the best in case of emergency cricothyroidotomy-a randomized cross-over trial on manikin focused training and simulation of common devices.

Background: Performing an emergency cricothyroidotomy (EC) is extremely challenging, the devices used should be easy to handle and the selected technique reliable. However, there is still an ongoing debate concerning the most superior technique. Methods: Three different techniques were compared using a standardized, simulated scenario regarding handling, performing, training and decision making: The scalpel-bougie technique (SBT), the surgical anatomical preparation technique (SAPT) and the Seldinger technique (ST). First, anaesthesia residents and trainees, paramedics and medical students (each group n = 50) performed a cricothyroidotomy randomly assigned with each of the three devices on a simulator manikin. The time needed for successful cricothyroidotomy was the primary endpoint. Secondary endpoints included first-attempt success rate, number of attempts and user-satisfaction. The second part of the study investigated the impact of prior hands-on training on both material selection for EC and on time to decision-making in a simulated "cannot intubate cannot ventilate" situation. Results: The simulated scenario revealed that SBT and SAPT were significantly faster than percutaneous EC with ST (p < 0.0001). Success rate was 100% for the first attempt with SBT and SAPT. Significant differences were found with regard to user-satisfaction between individual techniques (p < 0.0001). In terms of user-friendliness, SBT was predominantly assessed as easy (87%). Prior training had a large impact regarding choice of devises (p < 0.05), and time to decision making (p = 0.05; 180 s vs. 233 s). Conclusion: This study supports the use of a surgical technique for EC and also a regular training to create familiarity with the materials and the process itself.The trial was registered before study start on 11.11.2018 at ClinicalTrials.gov (NCT: 2018-13819) with Nicole Didion as the principal investigator.

18F-DCFPyL PSMA PET/CT Tracheobronchial Uptake in Patients with Prostate Cancer: Incidence and Etiology.

We evaluated the incidence and potential etiology of tracheobronchial uptake in patients being evaluated by 18F-DCFPyL PET/CT for prostate cancer (PCa). Methods: The study included a consecutive 100 PCa patients referred for 18F-DCFPyL PET/CT. The PET/CT scans were retrospectively reviewed. The presence or absence of physiologic tracheobronchial uptake on PET/CT was recorded. To further evaluate tracheal prostate-specific membrane antigen (PSMA) expression, immunohistochemistry was performed on tracheal samples taken from 2 men who had surgical resection of lung cancer. Results: Tracheal uptake was present in 31 of 100 patients (31%). When tracheal uptake was present, the SUVmax was significantly higher in the left main bronchus (mean, 2.7) than in the right (mean, 2.3) (P < 0.001). Histopathologic testing of tracheobronchial samples showed PSMA expression in bronchial submucosal glands. Conclusion: In PCa patients undergoing 18F-DCFPyL PET/CT, tracheobronchial uptake occurred in 31% of patients. This is attributed to normal physiologic PSMA expression in bronchial submucosal glands.

Endotracheal tube cuff position in relationship to the walls of the trachea: A retrospective computed tomography-based analysis.

Background: The use of cuffed endotracheal tubes (ETTs) has become the standard of care in pediatric practice. The rationale for the use of a cuffed ETT is to minimize pressure around the cricoid while providing an effective airway seal. However, safe care requires that the cuff lie distal to the cricoid ring following endotracheal intubation. The current study demonstrates the capability of computed tomography (CT) imaging in identifying the position of the cuff of the ETT in intubated patients. Methods: The study included patients ranging in age from 1 month to 10 years who underwent neck and chest CT imaging that required general anesthesia and endotracheal intubation. The location of the ETT and of the cuff within the airway was determined from axial CT images at three levels (proximal, middle, and distal). Anatomical orientations were tabulated, and percent chances of each orientation were determined for the ETT and the cuff. Results: The study cohort included 42 patients ranging in age from 1 to 114 months. An ETT with a polyvinylchloride cuff was used in 24 patients, and an ETT with a polyurethane cuff was used in 18 patients. The ETT was located near the posterior wall of the trachea in approximately 24-38% of patients, being most likely to be centrally located at the proximal end and at its mid-portion. The middle part of the cuff was most likely to be positioned in the mid-portion of the trachea but tended to skew anteriorly at both the proximal and distal ends. Conclusion: This is the first study using CT imaging to identify the uniformity of cuff inflation within the trachea in children. With commonly used cuffed ETTs, cuff inflation and the final position of ETT cuff within the tracheal lumen were not uniform. Future investigations are needed to determine the reasons for this asymmetry and its clinical implications.

Algorithm for airway management in benign intra-tracheal lesions.

The authors have conducted a retrospective analysis based on two cases of patients with intra-tracheal pathologies who received treatment from the same surgeon at a tertiary referral center. The effective management of airways in patients with intra-tracheal lesions necessitates close collaboration between surgeons and anesthesiologists. Factors such as the size, location, rigidity of the tumor, and the remaining tracheal lumen space should be carefully considered. In situations where there is near complete obstruction of the trachea and a substantial risk of worsened respiratory function, resorting to cardiopulmonary bypass or extracorporeal membrane oxygenation is advisable. This pilot study aims at devising an algorithm for the airway management of intra-tracheal lesions, although a larger case cohort is needed to assess its applicability and effectiveness.

Infiltration of nanocarbon into the trachea during thyroidectomy surgery: case series and literature review.

Introduction: The presence of metastatic disease in the cervical lymph nodes can affect the recurrence and survival of patients with thyroid cancer. Parathyroid gland injury during surgery can result in hypoparathyroidism, particularly with total thyroidectomy. Injection of carbon nanoparticles into the thyroid will label draining lymph nodes and aid in the visualization of metastatic cervical lymph nodes during a radical operation, sparing accidental damage to the parathyroid glands. Although reported to be useful during surgery, the safety of nanocarbon particles has rarely been investigated, and adverse side effects need to be studied. Case presentation: The author describes five patients with thyroid cancer who had carbon secretions in the trachea or mucosa after carbon nanoparticles were injected into the thyroid. A patient with carbon secretions in the trachea mucosa recovered but had progressive dyspnoea. Surgical treatment was performed, and a mass was found in the trachea mucosa. After excluding all other possibilities, the author concluded that the mass was caused by nanocarbon suspension. Discussion: To the author's knowledge, there are no reports on nanocarbon suspension into the mucosa and no consensus has yet been reached on the precise injection site, depth, or dose for injecting carbon nanoparticles before thyroidectomy. Conclusion: The author suggests that the most appropriate injection depth of nanocarbon suspensions should be no more than 3 mm of the thyroid gland thickness to avoid deep injection into the trachea.

Multi-Tissue Integrated Tissue-Engineered Trachea Regeneration Based on 3D Printed Bioelastomer Scaffolds.

Functional segmental trachea reconstruction is a critical concern in thoracic surgery, and tissue-engineered trachea (TET) holds promise as a potential solution. However, current TET falls short in fully restoring physiological function due to the lack of the intricate multi-tissue structure found in natural trachea. In this research, a multi-tissue integrated tissue-engineered trachea (MI-TET) is successfully developed by orderly assembling various cells (chondrocytes, fibroblasts and epithelial cells) on 3D-printed PGS bioelastomer scaffolds. The MI-TET closely resembles the complex structures of natural trachea and achieves the integrated regeneration of four essential tracheal components: C-shaped cartilage ring, O-shaped vascularized fiber ring, axial fiber bundle, and airway epithelium. Overall, the MI-TET demonstrates highly similar multi-tissue structures and physiological functions to natural trachea, showing promise for future clinical advancements in functional TETs.

A Clinical-Grade Partially Decellularized Matrix for Tracheal Replacement: Validation In Vitro and In Vivo in a Porcine Model.

The management of extensive tracheal resection followed by circumferential replacement remains a surgical challenge. Numerous techniques are proposed with mixed results. Partial decellularization of the trachea with the removal of the mucosal and submucosal cells is a promising method, reducing immunogenicity while preserving the biomechanical properties of the final matrix. Despite many research protocols and proofs of concept, no standardized clinical grade protocol is described. Furthermore, local and systemic biointegration mechanisms of decellularized trachea are not well known. Therefore, in a translational research perspective, this work set up a partial tracheal decellularization protocol in line with Cell and Tissue Products regulations. Extensive characterization of the final product is performed in vitro and in vivo. The results show that the Partially Decellularized Trachea (PDT) is cell-free in the mucosa and submucosa, while the cartilage structure is preserved, maintaining the biomechanical properties of the trachea. When implanted in the muscle in vivo for 28 days, no systemic inflammation is observed, and locally, the PDT shows an excellent biointegration and vascularization. No signs of graft rejection are observed. These encouraging results confirmed the efficacy of the clinical grade PDT production protocol, which is an important step for future clinical applications.

A Rare Case of Tracheal Lipoma in Puerto Rico: Presentation and Management of a Patient With Longstanding Respiratory Complaints.

Tracheal lipomas, though exceedingly rare among benign tracheal masses, present unique diagnostic and management challenges due to their unusual clinical course. This case report documents the presentation and surgical management of a 56-year-old male with a tracheal lipoma, a first documented case in Puerto Rico. The patient presented with progressive dyspnea and stridor, initially misdiagnosed and treated as asthma exacerbations. Imaging confirmed a pedunculated tracheal mass, prompting emergency surgical intervention to secure the airway and excise the mass successfully. Histopathological analysis confirmed the mass as a benign tracheal lipoma. This case emphasizes the importance of considering rare tracheal tumors in the differential diagnosis of unexplained respiratory distress and advocates for tailored management strategies informed by comprehensive multidisciplinary approaches.