[Cicatricial tracheal stenosis. Is prevention possible? A single-region experience]. / Rubtsovyi stenoz trakhei. Vozmozhna li ego profilaktika? Opyt odnogo regiona.

OBJECTIVE: To develop the measures for prevention and treatment of tracheal stenosis in various phases of disease. MATERIAL AND METHODS: We analyzed 290 patients who underwent long-term mechanical ventilation between 2006 and 2021. The main causes of previous intensive care with prolonged ventilation were combined trauma and stroke. All patients were divided into two groups. Group I included 149 people who underwent decannulation in a specialized department with further staged endoscopic follow-up. Group II included 141 patients with cicatricial tracheal stenosis and no follow-up. All patients underwent endoscopic treatment, tracheal resection and staged reconstructive plastic surgery. RESULTS: In the 1st group, tracheal stenosis occurred in 28 cases (18.8%). Of these, initial (edematous and granulation) stenoses were detected in 17 (60.7%), granulation-fibrous stenoses - in 11 (39.3%) cases. Endoscopic treatment was successful in 24 (85.7%) patients. Four patients with tracheomalacia underwent circular tracheal resections. In the 2nd group, all patients required surgical interventions (circular resections - 71 cases, staged reconstructive plastic surgery - 70 patients). Among 70 patients after reconstructive surgery, 24 (34.2%) ones recovered, and 28 (40%) patients need for cannula. Seventeen (24.2%) patients are unavailable for follow-up, and 1 patient (1.42%) died from concomitant disease. Complications after circular resection occurred in 16 cases (24.6%), postoperative mortality was 2.7%. CONCLUSION: Follow-up after prolonged mechanical ventilation and tracheotomy makes it possible to prevent severe forms of tracheal stenosis and carry out early endoscopic treatment.

Therapeutic and prophylactic effects of radiation therapy in the management of recurrent granulation tissue induced tracheal stenosis: a review on the role of Endobronchial brachytherapy and external beam radiation therapy.

PURPOSE: Granulation tissue-induced tracheal stenosis (mainly secondary to intubation or lung transplantation) is one of the most common etiologies of benign airway obstructions. Recurrence rates after standard treatment options (surgical resection and/or endobronchial interventions) can inadvertently worsen the stricture through the stimulation of more granulation tissue generation (via increased fibroblast activity and roliferation). Low-dose radiotherapy could be a promising tool to prevent granulation tissue formation after surgery and/or endobronchial interventions regarding its established role in the treatment of keloids or hypertrophic scars, two benign diseases with similar a pathophysiology to tracheal stenosis. This study reviews case reports and small series that used endobronchial brachytherapy (EBBT) or external beam radiotherapy (EBRT) for the management of refractory granulation tissue-induced tracheal stenosis after surgery and/or endobronchial interventions. METHODS AND MATERIALS: Case reports and series (published up to October 2022) that reported outcomes of patients with recurrent granulation tissue-induced tracheal stenosis (after surgery and/or endobronchial interventions) treated by EBBT or EBRT (in definitive or prophylactic settings) were eligible. RESULTS: Sixteen studies (EBBT: nine studies including 69 patients, EBRT: seven studies including 32 patients) were reviewed. The pooled success rate across all studies was 74% and 97% for EBBT and EBRT, respectively. CONCLUSIONS: Radiation therapy appears to be effective in the management of selected patients with recurrent/refractory tracheal stenosis. Response to this treatment is usually good, but further studies with a larger number of patients and long-term followup are necessary to determine the optimal technique, dose, and timing of radiation therapy, late complications, the durability of response, and criteria for patient selection.

Anti-inflammatory and Anti-bacterial Effects of Allicin-coated Tracheal Tube on Trachea Mucosa.

BACKGROUND/AIM: Allicin has been known to improve wound healing via antimicrobial and anti-inflammatory properties. The aim of this study was to evaluate whether an allicin-coated tracheal tube can prevent tracheal stenosis through improving wound healing after tracheal injury. MATERIALS AND METHODS: Allicin-coated silicone tracheal tube (t-tube) was prepared by the polydopamine-mediated coating method. Tracheal mucosa was injured, and an allicin-coated t-tube was placed into the trachea to evaluate mucosal changes until designated time point. Anti-inflammatory, anti-bacterial and cytotoxic effects of allicin were also investigated in in vitro. RESULTS: Allicin- coated silicone was not cytotoxic, and it showed anti-inflammatory and anti-bacterial effects in in vitro analysis. The use of allicin-coated t-tube in a rabbit model showed favorable mucosal healing with significant decrease of proinflammatory cytokines compared to the non-coated tube group. The allicin-coated tube showed obvious decreased number of cocci-shaped bacterial attached to the tube surface. From the histological point of view, the allicin- coated tube showed faster regeneration of the normal respiratory epithelial structure compared to the non-coated group. CONCLUSION: Allicin-coated t-tube showed anti-inflammatory and anti-bacterial effects on injured tracheal mucosa. We suggest that allicin-coated t-tube can be used for promoting physiological wound healing to prevent laryngotracheal stenosis.

Intraluminal Titanium Alloy Stent to Prevent Tracheal Stenosis in Tracheal Anastomosis.

BACKGROUND/AIM: Tracheal stenosis can cause respiratory problems in mature, small-breed dogs. This study aimed to evaluate the placement of an intratracheal titanium alloy stent to prevent tracheal stenosis in canine tracheal anastomosis. MATERIALS AND METHODS: The self-expandable intratracheal stent was an alloy of nickel and titanium, at the same atomic ratio. Vital signs and respiratory patterns, C-reactive protein, radiography, computed tomography, and endoscopy results after intraluminal stenting were assessed for 3-5 months. RESULTS: No dogs showed evidence of intraluminal tracheal stenosis or tracheitis in the region of stent insertion on tracheoscopy and computed tomography after tracheal stent placement. After 1-2 weeks of tracheal stent placement, all dogs resolved coughing and dyspnea signs and resumed normal activities. CONCLUSION: The intratracheal stent showed no movement or deformation in the trachea, and had flexibility and an appropriate radial force. Therefore, titanium alloy tracheal stents are useful in stenotic operations for tracheal reconstruction.

Protective effects of different anti­inflammatory drugs on tracheal stenosis following injury and potential mechanisms.

Tracheal stenosis following injury cannot be effectively treated. The current study compared the protective effects of different anti­inflammatory drugs on tracheal stenosis and investigated their possible mechanisms. Rabbit tracheal stenosis models following injury were constructed and confirmed using hematoxylin and eosin (H&E) staining. A total of 30 rabbits were divided into the control (CON), penicillin (PEN), erythromycin (ERY), budesonide (BUD) and PEN + ERY + BUD groups (n=6). Stenotic tracheal tissue, serum and bronchoalveolar lavage fluid (BALF) were collected 10 days after continuous treatment. Pathological changes in the tracheas were observed by H&E staining. Histone deacetylase 2 (HDAC2) expression in tracheal tissues was detected by immunofluorescence. Immunohistochemistry was performed to detect collagen I (Col­I) and collagen III (Col­III) levels in tracheal tissues. Transforming growth factor ß1 (TGF­ß1), vascular endothelial growth factor (VEGF) and interleukin 8 (IL­8) levels in serum and BALF samples were determined using ELISA kits. Western blotting detected HDAC2, IL­8, TGF­ß1 and VEGF levels in tracheal tissues. H&E staining demonstrated that tracheal epithelial hyperplasia and fibroblast proliferation in the ERY and PEN + ERY + BUD groups markedly improved compared with the CON group. Furthermore, in tracheal tissues, HDAC2 expression was significantly increased and IL­8, TGF­ß1, VEGF, Col­I and Col­III levels were significantly decreased in the ERY and PEN + ERY + BUD groups compared with the CON group. Additionally, the results for the PEN + ERY + BUD were more significant compared with the ERY group. In serum and BALF samples, IL­8, TGF­ß1 and VEGF levels in the ERY and PEN + ERY + BUD groups were significantly lower compared with the CON group, with the results of the PEN + ERY + BUD group being more significant compared with the ERY group. There were no significant differences between the PEN, BUD and CON groups. ERY inhibited tracheal granulation tissue proliferation and improved tracheal stenosis following injury and synergistic effects with PEN and BUD further enhanced these protective effects. The mechanism may involve HDAC2 upregulation and inhibition of local airway and systemic inflammatory responses.

Spatial and Temporal Analysis of Host Cells in Tracheal Graft Implantation.

OBJECTIVES/HYPOTHESIS: The ideal trachea replacement would be a living graft that is genetically identical to the host, avoiding the need for immunosuppression. We have developed a mouse model of syngeneic tracheal transplant that results in long-term survival without graft stenosis or delayed healing. To understand how host cells contribute to tracheal transplant integration, we quantified the populations of host cells in the graft and native trachea following implant. STUDY DESIGN: Tracheal transplant, tracheal replacement, regenerative medicine, animal model. METHODS: Tracheal grafts were obtained from female C57BL/6 mice and orthotopically transplanted into syngeneic male recipients. Cohorts were euthanized on day 14, day 45, and day 90 post-transplantation. Host and graft tracheas were explanted and analyzed by histology. Male host cells were quantified using fluorescence in situ hybridization, and macrophages were quantified with immunofluorescence. RESULTS: Evidence of host-derived cells was found in the midgraft at the earliest time point (14 days). Host-derived cells transiently increased in the graft on day 45 and were predominantly found in the submucosa. By day 90, the population of host-derived cells population declined to a similar level on day 14. Macrophage infiltration of host and graft tissue was observed at all time points and was greatest on day 90. CONCLUSIONS: Tracheal graft integration occurs by way of subacute transient host-cell infiltration and is primarily inflammatory in nature. Host-cell contribution to the graft epithelium is limited. These data indicate that creation of living, nonimmunogenic tracheal graft could serve as a viable solution for long-segment tracheal defects. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:E340-E345, 2021.

Fabrication and biological activity of polycaprolactone/phlorotannin endotracheal tube to prevent tracheal stenosis: An in vitro and in vivo study.

Prolonged endotracheal intubation is the most common cause of tracheal stenosis, which may lead to serious airway obstruction. Development of an endotracheal tube coated with biomaterials that exhibit anti-inflammatory or anti-fibrogenic effects may prevent tracheal stenosis. This study demonstrates that an endotracheal tube coated with phlorotannin, which is present in extracts of the brown alga Ecklonia cava, can prevent tracheal stenosis in a rabbit model. An in vitro study shows that phlorotannin inhibits proliferation of human tracheal fibroblasts treated with transforming growth factor ß1. Phlorotannin-coated endotracheal tubes show steady release of phlorotannin for up to 7 days, and removal of the tube 1 week after insertion reveals a reduction in both fibrogenesis and thickening of tracheal submucosa. Western blot analysis of tracheal tissues after removal of the phlorotannin-coated tube shows decreased protein expression levels of phenotypic markers of fibrosis such as collagen type I and α-smooth muscle actin. The ability of phlorotannin-coated endotracheal tube to prevent tracheal stenosis caused by endotracheal intubation indicates that phlorotannin may be considered as a candidate biomaterial for coating the cuff of endotracheal tubes to prevent tracheal stenosis.

Cuidados enfermeros para prevenir las complicaciones asociadas a la resección traqueal / Nursing care to prevent the complications associated with tracheal resection

Objetivo: describir las principales complicaciones asociadas a la cirugía de resección laringotraqueal e identificar los cuidados de Enfermería orientados a reducir las complicaciones asociadas. Método: revisión narrativa, se buscaron artículos en las bases de datos: Pubmed, CINAHL, Cochrane Library Plus y Cuiden, con los términos libres: "estenosis laringotraqueal", "estenosis traqueal", "complicaciones", "cirugía" y "cuidados". Limitados en idioma: inglés o español, edades superiores a 18 años y publicados en los últimos 10 años. Resultados: de un total de 143 artículos encontrados, 12 fueron seleccionados. Se identificaron las complicaciones postoperatorias: las anastomóticas (formación de tejido de granulación, re-estenosis, separación de la anastomosis o la aparición de fístula); y las no anastomóticas (edema laríngeo y la disfunción glótica). Cuidados derivados de la revisión: mantenimiento de la hiperflexión cervical temporal, evitar las náuseas y los vómitos, fomentar la movilización y la deambulación, y el control de los signos de alarma. Mediante estos cuidados se pretende reducir las variaciones inapropiadas de la práctica y promover una atención de calidad basada en la evidencia científica. Conclusiones: la necesidad de estandarizar los cuidados enfermeros a estos pacientes es fundamental para conseguir llevar a cabo un manejo óptimo y seguro para evitar complicaciones asociadas y disminuir el consumo de recursos sanitarios. El personal enfermero es un pilar importante para detectar estas complicaciones de forma precoz, ayudar a prevenir su aparición y favorecer a la autonomía del personal de Enfermería

Objective: to describe the main complications associated with laryngotracheal resection surgery, and to identify the Nursing care measures required to reduce the complications associated. Method: a narrative review. There was a search for articles in the following databases: Pubmed, CINAHL, Cochrane Library Plus and Cuiden, with the free terms: "estenosis laringotraqueal" ("laryngotracheal stenosis"), "estenosis traqueal" ("tracheal stenosis"), "complicaciones" ("complications"), "cirugía" ("surgery") and "cuidados" ("care"). Limited in language: English or Spanish; >18 years and published in the last 10 years. Results: twelve (12) articles were selected from the 143 articles found. Post-surgical complications were identified: anastomotic (granulation tissue formation, restenosis, anastomosis separation or development of fistula); and non-anastomotic (laryngeal oedema and glottic insufficiency). Care measures derived from the review: sustained temporary cervical hyperflexion, prevention of nausea and vomiting, encouraging mobility and ambulation, and control of warning signs. These care measures are intended to reduce any inappropriate variations in practice, and promote quality care based on scientific evidence. Conclusions: there is an essential need to standardize the nursing care for these patients, in order to achieve an optimal and safe management to avoid any complications associated and reduce the use of healthcare resources. Nursing staff plays an important role in the early detection of these complications, to help preventing their development, and to encourage the autonomy of the Nursing staff

Tracheal stenosis due to endotracheal tube cuff hyperinflation: a preventable complication

Endotracheal intubation injuries are rare, but may be devastating­mostly among the pediatric patients or when these occur in the distal trachea. Such complications typify a therapeutic challenge, which, besides requiring intellectual and technical resources, takes a long time to reach a resolution. The authors present the case of a 15-year-old girl admitted with an abnormal state of consciousness due to diabetic ketoacidosis. She was submitted to endotracheal intubation with hyperinflation of the tube cuff, which rendered tracheal necrosis and detachment of the tracheal mucosa, and consequent obstruction. Later, she developed scarring retraction and stenosis. The patient was successfully treated with an endotracheal prosthesis insertion. The aim of this report is to illustrate a preventable complication.

Prevention of tracheal stenosis with pirfenidone after tracheotomy: An experimental study.

OBJECTIVES: In this study, pirfenidone's role about reducing tracheal stenosis by suppressing fibrosis and inflammation was examined. METHODS: Tracheotomy was performed on 14 rats, and their cannulas were fixed to tracheotomy area by stoma suture. Two working groups were established. Rats in the first group were given 15 mg/kg/day (1 mL pirfenidone solution) pirfenidone intraperitoneally for 10 days. In the second group as a control group, 1 mL saline solution was applied intraperitoneally. Ten days later, rats were decanulated and kept alive for 3 more weeks. Anesthetized rats were sacrificed on day 30. All rat tracheas were resected between the first and seventh rings. Epithelial damage, inflammation, and fibrosis were determined histopathologically; diameters of intratracheal lumen and their mucosal thickness parameters were determined histomorphometrically; and TGFß-1 (the growth factor beta), TNFα (tumor necrosis factor alpha), and IL-1ß (Interleukin-1 beta) values were determined immunohistochemically. RESULTS: According to the parameters of the control group, fibrosis; diameters of intratracheal lumen; and values of TGFß-1, TNFα, and IL-1ß were found to be statistically significant. CONCLUSION: In our study, it was found that pirfenidone reduces fibrosis and narrowing of intratracheal lumen diameter significantly. LEVEL OF EVIDENCE: NA Laryngoscope, 129:E178-E186, 2019.

[The possibilities for the prevention of incompetent tracheorrhaphy]. / Vozmozhnosti preduprezhdeniia nesostoiatel'nosti shvov trakhei.

The present review of the literature is focused on the methods designed for the prevention of incompetent tracheorrhaphy. The main cause that dictates the necessity of strengthening the sutures is the risk of the development of the complications during the postoperative period following the surgical interventions. The incompetence of the tracheal anastomoses is known to occur in 3.6-26.3% of the patients which leads to the development of such complications as neck phlegmon, mediastinitis, and pleural empyema. The mortality rate amounts to 18.2%. The authors describe the methods employed for the prevention of incompetent tracheorrhaphy following the circular resections and suturing of the linear traumatic defects. The advantages and disadvantages of individual methods are discussed.

Tracheal Injuries Complicating Prolonged Intubation and Tracheostomy.

Respiratory care advances such as the introduction of ventilatory assistance have been associated with postintubation airway stenosis resulting from tracheal injury at the site of the inflatable cuff on endotracheal or tracheostomy tubes. Low-pressure cuffs have significantly reduced this occurrence. Loss of airway stability at the site of a tracheostomy stoma may result in tracheal stenosis. Subglottic stenosis may result from a high tracheostomy site at, or just inferior to, the cricoid arch, or to malposition of an endotracheal tube cuff. Awareness of these complications and their causes is essential to prevent their occurrence.

Prevention of tracheal inflammation and fibrosis using nitinol stent coated with doxycycline.

OBJECTIVES: This study was conducted to determine whether a nitinol stent coated with doxycycline prevents tracheal inflammation and fibrosis in a rabbit. METHODS: A nitinol stent coated with doxycycline was designed by us. Twelve rabbits were divided into three groups: normal, control (nondoxycycline-coated stent), and doxycycline-coated stent group. The stents were inserted into the tracheal lumen through the oral cavity. Tracheal granulation was evaluated and graded by laryngoscopy. Histological examinations evaluated the inflammatory response and fibrosis. Real-time polymerase chain reaction (PCR) and Western blot assessed the changes to the extracellular matrix (ECM). RESULTS: Endoscopic findings showed that the nitinol stent coated with doxycycline resulted in lesser granulation tissue in the trachea than the noncoated stent. Histologic examination further revealed that the doxycycline-coated stent was associated with decreased inflammatory cells and reduced fibrosis, compared to the noncoated stent. In PCR and Western blot, the doxycycline-coated stent showed lower expression of ECM components inducing fibrosis. CONCLUSION: A nitinol stent coated with doxycycline showed favorable effects in reducing tracheal inflammation and fibrosis in a rabbit model. Further research is required to study the beneficial effects of local application of doxycycline for prevention of tracheal stenosis. LEVEL OF EVIDENCE: NA. Laryngoscope, 128:1558-1563, 2018.

An Overview of Tracheal Stenosis Research Trends and Hot Topics.

BACKGROUND: Tracheal stenosis remains a challenge in the thoracic surgery field. Recognizing the hot topics and major concepts in this area would help the health policy makers to determine their own priorities and design the effective research plans. The present study analyzed and mapped the topics and trends of tracheal stenosis studies over time as well as authors' and countries' contributions. MATERIALS AND METHODS: Search results were obtained employing Bibexcel. To determine cold and hot topics, co-occurrence analysis was applied using three international databases 'Web of Science', 'PubMed' and 'Scopus'. Appropriately, different categories in the articles such as keywords, authors, and countries were explored via VOSviewer and NetDraw. Afterward, the trends of research topics were depicted in four time-intervals from 1945 to 2015 by ten co-occurrence terms. RESULTS: The majority of articles were limited to case series and retrospective studies. The studies had been conducted less frequently on prevention, risk factors and incidence determination but extensively on treatment and procedures. Based on the articles indexed in WOS, 45 countries and 8,260 authors have contributed to scientific progress in this field. The highest degree of cooperation occurred between the USA and England with 15 common papers. CONCLUSIONS: Most of the published literature in tracheal stenosis research field was about surgical and non-surgical treatments. Conducting the screening and prevention studies would diminish the burden of this disease on the health system as well as the patients and their families' well-being.

Effects of artificial tracheal fixation on tracheal epithelial regeneration and prevention of tracheal stenosis.

CONCLUSION: Tight fixation of the artificial trachea is important for epithelialization and tracheal stenosis. OBJECTIVE: The authors have developed an artificial trachea and have used it for tracheal reconstruction. Although various studies on tracheal reconstruction have been conducted, no studies have examined the effect of artificial tracheal fixation on tracheal stenosis and regeneration. Therefore, the purpose of the present study was to evaluate the effect of artificial tracheal fixation. STUDY DESIGN: Preliminary animal experiment. METHODS: Artificial tracheae were implanted into rabbits with partial tracheal defects. Tracheal stenosis and regeneration of the tracheal epithelium on the artificial tracheae were evaluated by endoscopic examination, scanning electron microscopic analysis, and histological examination. The artificial tracheae fixed to the tracheal defects were classified into three groups (0-point, 4-point, and 8-point) by the number of fixation points. RESULTS: At 14 and 28 days post-implantation, the luminal surface of the implantation area was mostly covered with epithelium in all fixation groups. However, a small amount of granulation tissue was observed in the 0-point fixation group at 14 days post-implantation. Moreover, tracheal stenosis did not occur in the 8-point fixation group, but stenosis was detected in the other groups.

Tanshinone IIA attenuates epithelial-mesenchymal transition to inhibit the tracheal narrowing.

BACKGROUND: This study examines the effects of tanshinone IIA (TIIA) on epithelial-mesenchymal transition (EMT) in tracheal transplantation and the ability of TIIA to inhibit tracheal narrowing after tracheal transplantation. Mechanisms that may be involved in this process are also explored. METHODS: Human bronchial epithelial cells were treated in vitro with TGF-ß1 for 72 h. The cells were pretreated with TIIA (40 µg/mL) or DMSO for 2 h before TGF-ß1 stimulation. For the in vivo experiments, tracheas (5-6 rings) from Wistar rats were orthotopically transplanted into Sprague-Dawley rats. The experimental group received multiple infusions of sodium TIIA sulfonate (25 mg/kg, qd, intraperitoneally). The control group received infusions of the same volume of saline. Allografts were harvested at 3, 7, 10, 14, 35, and 90 d after transplantation and were examined for tracheal narrowing. Tracheal tissue samples and human bronchial epithelial cell were then subjected to further tests. RESULTS: In the in vitro assay, epithelial cadherin expression was decreased after TGF-ß1 stimulation, whereas α-smooth muscle actin and vimentin expression levels were increased. The expression levels of ZEB1 and Snail1 were also increased. These changes in expression were partially reversed by treatment with TIIA. In the in vivo assay, TIIA alleviated tracheal stenosis after tracheal allograft transplantation in rats and mitigated EMT by inhibiting the Smad signaling pathway and the expression of the transcription factors ZEB1 and Snail1. CONCLUSIONS: Our research suggests that TIIA reduces tracheal narrowing after tracheal transplantation by suppressing TGF-ß1-dependent EMT.

[The methods for the treatment and prevention of cicatrix stenoses of trachea].

The objective of the present study was to analyze the current literature concerning mechanisms underlying the development of tracheal stenosis, new methods for the treatment and prevention of this condition. The main cause behind the formation of cicatrical stenosis of trachea is believed to be long-term artificial lung ventilation whereas the principal factors responsible for the injury to the tracheal wall include the impact of the cuff and the free end of the endotracheal tube, reflux of duodenal and gastric contents, concomitant infection, and the involvement of the autoimmune component. These pathogenic factors produce morphological changes in all layers of the tracheal wall with the formation of the granulation tissue the appearance of which serves as a forerunner of irreversible changes leading to tracheal stenosis. The biomedical technologies including auto- and allo-transplantation, tissue engineering, gene and cell-based therapy are considered to be the most promising methods for the treatment and prevention of this condition likely to improve the outcome of the management of cicatrical tracheal stenosis.

En la estenosis traqueal benigna nunca deberían emplearse endoprótesis metálicas / Benign tracheal stenosis should never be stented with metallic devices

No disponible

Stents traqueales metálicos autoexpandibles. Estudio comparativo de 3 tipos diferentes de stents en un modelo animal / Tracheal Self-Expandable Metallic Stents: A Comparative Study of Three Different Stents in a Rabbit Model

Introducción: El objetivo de este estudio es evaluar l8mm frea reactividad traqueal tras la implantación de distintos stents metálicos autoexpandibles (SMAE). Material y métodos: Se utilizaron 40 conejos hembra de raza neozelandesa, que se dividieron en 4 grupos. En 3 grupos se implantaron SMAE: de acero (SA), de nitinol (NiTi) o stents liberadores de nitinol (SLF). El cuarto grupo fue el grupo de control (sin stent). Los stents se implantaron por vía percutánea bajo control fluoroscópico. Los animales se evaluaron mediante tomografía axial computarizada (TAC) multicorte y las tráqueas se extirparon para su estudio anatomopatológico (EAP). Los datos de la TAC y el EAP se analizaron estadísticamente y se correlacionaron. Resultados: El grupo que recibió SLF presentaba la mayor longitud de estenosis (20,51 ± 14,0nte a 5,84 ± 12,43 y 6,57 ± 6,54 mm en los grupos NiTi y SA, día 30; p < 0,05) y el mayor índice de formación de granulomas evidenciados mediante TAC (50% de los casos). El grupo al que se implantaron stents NiTi mostró el menor grado de estenosis (2,86 ± 6,91% frente a 11,28 ± 13,98 y 15,54 ± 25,95% en los grupos SLF y SA; p<0,05). En el estudio AP, el grupo SA presentó reactividad proliferativa intensa en comparación con los otros 2 grupos. En el grupo SLF se observó una respuesta destructiva en el 70% de animales, mientras que el stent NiTi fue el que menos reacción provocó. La TAC resultó ser superior para detectar el engrosamiento (correlación positiva de un 68,9%; p < 0,001) que para la observación de granulomas (n.s.). Conclusiones: El grupo SA desarrolló granulomas y estenosis significativas. El stent NiTi fue el que menos reacción indujo, mientras que el SLN provocó lesiones importantes que podrían estar relacionadas con la dosis de fármaco. Por consiguiente, este tipo de SLF no se recomienda para el tratamiento de la estenosis traqueobronquial

Introduction: The objective of this study was to assess tracheal reactivity after the deployment of different self-expandable metal stents (SEMS). Material and methods: Forty female New Zealand rabbits were divided into four groups. Three groups received three different SEMS: steel (ST), nitinol (NiTi), or nitinol drug-eluting stent (DES); the fourth group was the control group (no stent). Stents were deployed percutaneously under fluoroscopic guidance. Animals were assessed by multi-slice, computed tomography (CT) scans, and tracheas were collected for anatomical pathology (AP) study. Data from CT and AP were statistically analyzed and correlated. Results: The DES group had the longest stenosis (20.51 ± 14.08 mm vs. 5.84 ± 12.43 and 6.57 ± 6.54 mm in NiTi and ST, respectively, day 30; P < .05), and higher granuloma formation on CT (50% of cases). The NiTi group showed the lowest grade of stenosis (2.86 ± 6.91% vs. 11.28 ± 13.98 and 15.54 ± 25.95% in DES and ST, respectively; P<.05). The AP study revealed that the ST group developed intense proliferative reactivity compared to the other groups. In the DES group, a destructive response was observed in 70% of the animals, while the NiTi was the least reactive stent. CT was more effective in detecting wall thickening (positive correlation of 68.9%; P < .001) than granuloma (not significant). Conclusions: The ST group developed granulomas and significant stenosis. NiTi was the least reactive stent, while DES caused significant lesions that may be related to drug dosage. This type of DES stent is therefore not recommended for the treatment of tracheobronchial stenosis