Search Results (13)

Background: Mediastinal mass syndrome represents a major threat to respiratory and cardiovascular integrity, with difficult evidence-based risk stratification for interdisciplinary management. Methods: We conducted a narrative review concerning risk stratification and difficult airway management of patients presenting with a large mediastinal mass. This is supplemented by a case report illustrating our individual approach for a patient presenting with a subtotal tracheal stenosis due to a large cyst of the thyroid gland. Results: We identified numerous risk stratification grading systems and only a few case reports of regional anesthesia techniques for extracorporeal membrane oxygenation patients. Clinical Case: After consultation with his general physician because of exertional dyspnea and stridor, a 78-year-old patient with no history of heart failure was advised to present to a cardiology department under the suspicion of decompensated heart failure. Computed tomography imaging showed a large mediastinal mass that most likely originated from the left thyroid lobe, with subtotal obstruction of the trachea. Prior medical history included the implantation of a dual-chamber pacemaker because of a complete heart block in 2022, non-insulin-dependent diabetes mellitus type II, preterminal chronic renal failure with normal diuresis, arterial hypertension, and low-grade aortic insufficiency. After referral to our hospital, an interdisciplinary consultation including experienced cardiac anesthesiologists, thoracic surgeons, general surgeons, and cardiac surgeons decided on completing the resection via median sternotomy after awake cannulation for veno-venous extracorporeal membrane oxygenation via the right internal jugular and the femoral vein under regional anesthesia. An intermediate cervical plexus block and a suprainguinal fascia iliaca compartment block were performed, followed by anesthesia induction with bronchoscopy-guided placement of the endotracheal tube over the stenosed part of the trachea. The resection was performed with minimal blood loss. After the resection, an exit blockade of the dual chamber pacemaker prompted emergency surgical revision. The veno-venous extracorporeal membrane oxygenation was explanted after the operation in the operating room. The postoperative course was uneventful, and the patient was released home in stable condition. Conclusions: Awake veno-venous extracorporeal membrane oxygenation placed under local anesthetic infiltration with regional anesthesia techniques is a feasible individualized approach for patients with high risk of airway collapse, especially if the mediastinal mass critically alters tracheal anatomy. Compressible cysts may represent a subgroup with easy passage of an endotracheal tube. Interdisciplinary collaboration during the planning stage is essential for maximum patient safety. Prospective data regarding risk stratification for veno-venous extracorporeal membrane oxygenation cannulation and effectiveness of regional anesthesia is needed. Full article

Tracheal stenosis (i.e., the abnormal narrowing of the trachea) can occur due to a variety of inflammatory and infectious processes as well as due to therapeutic procedures undertaken by the patient. The most common cause of tracheal obstruction in patients has been prolonged intubation. Depending on the extent of the stenosis and its exact location, the surgical insertion of a tracheal stent is the only option for addressing this issue. The Montgomery T-tube implant is a valuable tracheal stent made from medical-grade silicone that provides a functional airway while supporting the tracheal mucosa. However, its performance is subject to gradual deterioration due to biofilm colonization of the stent’s inner wall, which may explain the discomfort claimed by many patients and clinical failures. Recently, cold atmospheric plasmas (CAPs) have emerged as an alternative technology to many conventional medical procedures, such as wound healing, skin treatment, decontamination of medical devices, etc. Here, we report on plasma-induced surface modification of the inner wall of a T-tube implant, considering future biomedical applications. To generate the plasma, we employed a cold atmospheric pressure plasma jet in gas helium, which was directly inserted into the T-tube implant. To assess the treatment uniformity, the degree of surface modification and its extension along the stent’s inner wall was analyzed using different process parameters. Full article

Subglottic stenosis (SGS) is a rare yet potentially life-threatening condition that requires prompt identification and treatment. One of the primary symptoms of SGS is a respiratory sound that is tonal. To better understand the effect of SGS on expiratory sound, we used direct noise calculation to simulate sound production in a simplified axisymmetric configuration that included the trachea, the vocal folds, the supraglottal tract, and an open environmental space. This study focused on flow-sustained tones and explored the impact of various parameters, such as the SGS severity, the SGS distance, the flowrate, and the glottal opening size. It was found that the sound pressure level (SPL) of the expiratory sound increased with flowrate. SGS had little effect on the sound until its severity approached 75% and SPL increased rapidly as the severity approached 100%. The results also revealed that the tonal components of the sound predominantly came from hole tones and tract harmonics and their coupling. The spectra of the sound were greatly influenced by constricting the glottis, which suggests that respiratory tasks that involve maneuvers to change the glottal opening size could be useful in gathering more information on respiratory sound to aid in the diagnosis of subglottic stenosis. Full article

Background: Our aim was to report on the use of an innovative technique for airway management utilizing a small diameter, short-cuffed, long orotracheal tube for assisting operative rigid bronchoscopy in critical airway obstruction. Methods: We retrospectively reviewed the clinical data of 36 patients with life-threatening critical airway stenosis submitted for rigid bronchoscopy between January 2008 and July 2021. The supporting ventilatory tube, part of the Translaryngeal Tracheostomy KIT (Fantoni method), was utilized in tandem with the rigid bronchoscope during endoscopic airway reopening. Results: Indications for collateral intubation were either tumors of the trachea with near-total airway obstruction (13), or tumors of the main carina with total obstruction of one main bronchus and possible contralateral involvement (23). Preliminary dilation was necessary before tube placement in only 2/13 patients with tracheal-obstructing tumors (15.4%). No postoperative complications were reported. There was one case of an intraoperative cuff tear, with no further technical problems. Conclusions: In our experience, this innovative method proved to be safe, allowing for continuous airway control. It enabled anesthesia inhalation, use of neuromuscular blockage and reliable end-tidal CO₂ monitoring, along with protection of the distal airway from blood flooding. The shorter time of the procedure was due to the lack of need for pauses to ventilate the patient. Full article

Tracheal replacement with a bioengineered tracheal substitute has been developed for long-segment tracheal diseases. The decellularized tracheal scaffold is an alternative for cell seeding. It is not defined if the storage scaffold produces changes in the scaffold’s biomechanical properties. We tested three protocols for porcine tracheal scaffold preservation immersed in PBS and alcohol 70%, in the fridge and under cryopreservation. Ninety-six porcine tracheas (12 in natura, 84 decellularized) were divided into three groups (PBS, alcohol, and cryopreservation). Twelve tracheas were analyzed after three and six months. The assessment included residual DNA, cytotoxicity, collagen contents, and mechanical properties. Decellularization increased the maximum load and stress in the longitudinal axis and decreased the maximum load in the transverse axis. The decellularization of the porcine trachea produced structurally viable scaffolds, with a preserved collagen matrix suitable for further bioengineering. Despite the cyclic washings, the scaffolds remained cytotoxic. The comparison of the storage protocols (PBS at 4 °C, alcohol at 4 °C, and slow cooling cryopreservation with cryoprotectants) showed no significant differences in the amount of collagen and in the biomechanical properties of the scaffolds. Storage in PBS solution at 4 °C for six months did not change the scaffold mechanics. Full article

Tracheal stenosis and defects occur congenitally and in patients who have undergone tracheal intubation and tracheostomy due to long-term intensive care. Such issues may also be observed during tracheal removal during malignant head and neck tumor resection. However, to date, no treatment method has been identified that can simultaneously restore the appearance of the tracheal skeleton while maintaining respiratory function in patients with tracheal defects. Therefore, there is an urgent need to develop a method that can maintain tracheal function while simultaneously reconstructing the skeletal structure of the trachea. Under such circumstances, the advent of additive manufacturing technology that can create customized structures using patient medical image data provides new possibilities for tracheal reconstruction surgery. In this study, the three-dimensional (3D) printing and bioprinting technologies used in tracheal reconstruction are summarized, and various research results related to the reconstruction of mucous membranes, cartilage, blood vessels, and muscle tissue, which are tissues required for tracheal reconstruction, are classified. The prospects for 3D-printed tracheas in clinical studies are also described. This review serves as a guide for the development of artificial tracheas and clinical trials using 3D printing and bioprinting. Full article

Subglottic stenosis represents a challenging clinical condition in otolaryngology. Although patients often experience improvement following endoscopic surgery, recurrence rates remain high. Pursuing measures to maintain surgical results and prevent recurrence is thus necessary. Steroids therapy is considered effective in preventing restenosis. Currently, however, the ability of trans-oral steroid inhalation to reach and affect the stenotic subglottic area in a tracheotomized patient is largely negligible. In the present study, we describe a novel trans-tracheostomal retrograde inhalation technique to increase corticosteroid deposition in the subglottic area. We detail our preliminary clinical outcomes in four patients treated with trans-tracheostomal corticosteroid inhalation via a metered dose inhaler (MDI) following surgery. Concurrently, we leverage computational fluid-particle dynamics (CFPD) simulations in an extra-thoracic 3D airway model to gain insight on possible advantages of such a technique over traditional trans-oral inhalation in augmenting aerosol deposition in the stenotic subglottic region. Our numerical simulations show that for an arbitrary inhaled dose (aerosols spanning 1–12 µm), the deposition (mass) fraction in the subglottis is over 30 times higher in the retrograde trans-tracheostomal technique compared to the trans-oral inhalation technique (3.63% vs. 0.11%). Importantly, while a major portion of inhaled aerosols (66.43%) in the trans-oral inhalation maneuver are transported distally past the trachea, the vast majority of aerosols (85.10%) exit through the mouth during trans-tracheostomal inhalation, thereby avoiding undesired deposition in the broader lungs. Overall, the proposed trans-tracheostomal retrograde inhalation technique increases aerosol deposition rates in the subglottis with minor lower-airway deposition compared to the trans-oral inhalation technique. This novel technique could play an important role in preventing restenosis of the subglottis. Full article

Mucopolysaccharidosis (MPS) is a hereditary disorder arising from lysosomal enzymes deficiency, with glycosaminoglycans (GAGs) storage in connective tissues and bones, which may compromise the airway. This retrospective study evaluated patients with MPS type IVA with airway obstruction detected via endoscopy and imaging modalities and the effects of surgical interventions based on symptoms. The data of 15 MPS type IVA patients (10 males, 5 females, mean age 17.8 years) were reviewed in detail. Fiberoptic bronchoscopy (FB) was used to distinguish adenotonsillar hypertrophy, prolapsed soft palate, secondary laryngomalacia, vocal cord granulation, cricoid thickness, tracheal stenosis, shape of tracheal lumen, nodular deposition, tracheal kinking, tracheomalacia with rigid tracheal wall, and bronchial collapse. Computed tomography (CT) helped to measure the deformed sternal angle, the cross-sectional area of the trachea, and its narrowest/widest ratio (NW ratio), while angiography with 3D reconstruction delineated tracheal torsion, kinking, or framework damage and external vascular compression of the trachea. The NW ratio correlated negatively with age (p < 0.01), showing that airway obstruction progressed gradually. Various types of airway surgery were performed to correct the respiratory dysfunction. MPS type IVA challenges the management of multifactorial airway obstruction. Preoperative airway evaluation with both FB and CT is strongly suggested to assess both intraluminal and extraluminal factors causing airway obstruction. Full article

Airway stenosis is a global respiratory health problem that is caused by airway injury, endotracheal intubation, malignant tumor, lung aging, or autoimmune diseases. A precise understanding of the airflow dynamics and pharmaceutical aerosol transport through the multi-stenosis airways is vital for targeted drug delivery, and is missing from the literature. The object of this study primarily relates to behaviors and nanoparticle transport through the multi-stenosis sections of the trachea and upper airways. The combination of a CT-based mouth–throat model and Weibel’s model was adopted in the ANSYS FLUENT solver for the numerical simulation of the Euler–Lagrange (E-L) method. Comprehensive grid refinement and validation were performed. The results from this study indicated that, for all flow rates, a higher velocity was usually found in the stenosis section. The maximum velocity was found in the stenosis section having a 75% reduction, followed by the stenosis section having a 50% reduction. Increasing flow rate resulted in higher wall shear stress, especially in stenosis sections. The highest pressure was found in the mouth–throat section for all flow rates. The lowest pressure was usually found in stenosis sections, especially in the third generation. Particle escape rate was dependent on flow rate and inversely dependent on particle size. The overall deposition efficiency was observed to be significantly higher in the mouth–throat and stenosis sections compared to other areas. However, this was proven to be only the case for a particle size of 1 nm. Moreover, smaller nanoparticles were usually trapped in the mouth–throat section, whereas larger nanoparticle sizes escaped through the lower airways from the left side of the lung; this accounted for approximately 50% of the total injected particles, and 36% escaped from the right side. The findings of this study can improve the comprehensive understanding of airflow patterns and nanoparticle deposition. This would be beneficial in work with polydisperse particle deposition for treatment of comprehensive stenosis with specific drugs under various disease conditions. Full article

Decellularization has emerged as a potential solution for tracheal replacement. As a fully decellularized graft failed to achieve its purposes, the de-epithelialization partial decellularization protocol appeared to be a promising approach for fabricating scaffolds with preserved mechanical properties and few immune rejection responses after transplantation. Nevertheless, a lack of appropriate concurrent epithelialization treatment can lead to luminal stenosis of the transplant and impede its eventual success. To improve re-epithelialization, autologous nasal epithelial cell sheets generated by our cell sheet engineering platform were utilized in this study under an in vivo rabbit model. The newly created cell sheets have an intact and transplantable appearance, with their specific characteristics of airway epithelial origin being highly expressed upon histological and immunohistochemical analysis. Subsequently, those cell sheets were incorporated with a partially decellularized tracheal graft for autograft transplantation under tracheal partial resection models. The preliminary results two months post operation demonstrated that the transplanted patches appeared to be wholly integrated into the host trachea with adequate healing of the luminal surface, which was confirmed via endoscopic and histologic evaluations. The satisfactory result of this hybrid scaffold protocol could serve as a potential solution for tracheal reconstructions in the future. Full article

In this study, we fabricated a doxycycline (doxy)-eluting nanofiber-covered endotracheal stent for the prevention of stent intubation-related tissue fibrosis and re-stenosis. The nanofiber was deposited directly on the outer surface of the stent using a coaxial electrospinning method to form a doxy-eluting cover sleeve. Poly(d,l-lactide) was used as the shell-forming polymer and dedicated drug release-control membrane. Polyurethane was selected as the drug-loading core polymer. The compositional ratio of the core to shell was adjusted to 1:0, 1:2, and 1:4 by changing the electro-spray rate of each polymeric solution and microscopic observation of nanofibers using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the fluorescence microscopy proved core-shell structure of nanofibers. The in vitro release study suggested that the release of doxy could be controlled by increasing the compositional ratio of the shell. The growth of HT1080 fibrosarcoma cells was inhibited by the 10% doxy-containing nanofiber. The real-time polymerase chain reaction (PCR) in HT1080 cells and xenografted tissue models indicated that the doxy-releasing nanofiber inhibited mRNA expression of metalloproteinases (MT1-MMP, MMP-2, and MMP-9). Overall, our study demonstrates that a doxy-eluting core-shell nanofiber stent can be successfully fabricated using coaxial electrospinning and displays the potential to prevent fibrotic re-stenosis, which is the most problematic clinical complication of tracheal stent intubation. Full article

Tracheobronchopathia osteochondroplastica (TBO) is a rare disease of unknown etiology characterised by a formation of multiple, cartilaginous and osteocartilaginous submucosal nodules in the trachea and major bronchi. The course of the disease is usually benign but the narrowing of the respiratory tract can lead to chronic non-specific clinical symptoms. We present a case of a 50-year old man with chronic exertional dyspnoea and stenosis of the trachea visible in imaging tests, in whom the symptoms were caused by TBO. Full article

Introduction: Virtual bronchoscopy (VB) is a new, noninvasive diagnostic technique that allows visualization of trachea and bronchi. Virtual images are created based on scans from helical multidetector computed tomography (CT) scans using a special protocol. The obtained reconstructed virtual image of the bronchial tree reflects pictures seen under conventional fibre-optic bronchoscopy (FOB). The aim of the study was to compare VB images of the bronchial tree with findings from FOB and to evaluate the diagnostic value of VB in the examination of central lung tumours. Material and methods: The studied group consisted of 40 patients with suspected central lung tumours, detected first on chest X-ray. Each patient underwent routine CT and FOB, followed by VB. Physicians performing FOB were blinded to VB results and vice versa. The presence of tumour, bronchial stenosis, and widening of the carina were the analysed features. Lung cancer was confirmed by histopathological examination in all patients, including 32 cases of non-small cell lung cancer (80%), 2 cases of small cell lung cancer (5%), 5 cases of squamous cell carcinoma (12.5%), and one case of carcinoid (2.5%). Results: Virtual bronchoscopy for bronchial tumour detection had a sensitivity of 79.5% and specificity of 95.5%. When bronchial stenosis was assessed, sensitivity was 58.6% and specificity was 98.1%, whereas detection of widening of carina had a sensitivity of 60.7% and specificity of 97.7%. Conclusions: The results indicate that virtual bronchoscopy is a highly sensitive and specific diagnostic method, of high clinical importance in the evaluation of lung tumours with central location. Full article