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This paper deals with two-dimensional motion analysis of vehicles damaged due to collision. Various parts of vehicles are damaged due to collision in general. The effects of the damage in vehicle body and wheels on the vehicle motions are investigated. The center of gravity of the vehicle and the polar moment of inertia are changed by the deformation of vehicle body. Furthermore, the geometrical relations of wheels like wheelbase, treads and steering angles may be changed by damage of the wheels. Thus the vehicle loses symmetry with respect to the vehicle axis. The four-wheel vehicle model is extended to take into account the vehicle damage due to collision. The motions of damaged vehicles are compared with those of undamaged vehicles. It is found that vehicle damages have a significant influence on vehicle motion after impact. [ABSTRACT FROM AUTHOR]

This paper deals with two-dimensional motion of vehicles. Since the general four-wheel vehicle model is statically indeterminate, the motion of vehicles has been analyzed by replacing the vehicle with the equivalent two-wheel one proposed by E. Marquard. Because this approximation is based on the axisymmetry of vehicles, it causes significant errors in the general case. To improve the accuracy of the analysis of vehicle motion, a four-wheel model is suggested. In this model, it is assumed that the chassis remains in a flat plane during motion. By introducing this condition, the motion of the vehicle can be analyzed. Several results from the four-wheel model and the equivalent two-wheel model are shown for comparison, and the vehicle trajectories with time are discussed. [ABSTRACT FROM AUTHOR]

Objective: The patient's journey to the medical center for an outpatient visit can often mean hours of travel in their vehicle, leading to increased expenses and greater carbon dioxide (CO2) emissions into the environment. The study demonstrates the estimated carbon emission and cost savings associated with a telemedicine program dedicated to patients with tracheal disease in the Brazilian public health system., Methods: Cross-sectional study of telemedicine visits for patients with tracheal disease referred to a public academic hospital between August 1, 2020, and December 30, 2023. The consultations occurred in a telemedicine department using the hospital's proprietary platform. The analysis included the round-trip distance savings using home postal codes; CO2 emissions savings by transportation using the Greenhouse Gas Protocol (GHG Protocol) adapted to the Brazilian reality ("Programa Brasileiro GHG Protocol"); and the cost savings in transportation and support using the Brazil Ministry of Health program., Results: 1767 telemedicine visits with 680 patients were conducted, 363 (53.4 %) male and 317 (46.6 %) female, a median [IQR] age of 33 [12.0-51.0] years. Patients were from 170 Brazilian cities from 22 states. There were 2.219.544,3 round-trip kilometers saved (median per patient [IQR] 542,88km [190,36-2.672,6]), corresponding to an estimated 353.097,55kg of CO2 emissions savings (median per patient [IQR] 102,56kg [36,56-496,96]). The cost savings was 305.187,96 dollars (median per patient [IQR] $48,22 [24,97-162,51] dollars)., Conclusion: Telemedicine consultations, in addition to significantly reducing carbon emissions and costs, promote greater accessibility and sustainability in medical care. These findings may influence public policies to expand telemedicine programs, especially in remote regions, and strengthen environmental initiatives in healthcare., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

To compare two different wavelengths of the surgical contact diode laser (CDL) for producing a posterior laryngofissure in in-vivo pigs. Anesthetized pigs underwent a tracheostomy and an anterior laryngofissure through a cervicotomy. They were randomly selected for the CDL wavelength and Power, according to the peak of Power set at device (980nm wavelength: Ppeak power of 10 W, 15 W, and 20 W, or 1470 nm wavelength: Ppeak 3 W, 5 W, 7 W, 10 W). At the end of the experiment, the laryngotracheal specimen was extracted and sent for histology and morphometry measurements (incision size, depth, area, and lateral thermal damage). Hemodynamic data and arterial blood gases were recorded during the incisions. Statistical analysis of the comparisons between the parameters and groups had a level of significance of p < 0.05. Twenty-six pigs were divided into CDL 980 nm (n = 11) and 1470 nm (n = 15). There was a greater incision area at the thyroid level in the 980 nm CDL and a wider incision at the trachea level, with a larger distance between mucosa borders. There were no significant differences in the area of lateral thermal damage between the two groups and neither difference among the power levels tested. Both wavelengths tested showed similar results in the various combinations of power levels without significant differences in the lateral thermal damage. The posterior laryngofissure incision can be performed by either of the wavelengths at low and medium power levels without great difference on lateral thermal damage., (© 2024. The Author(s).)

Background: Central airway diseases requiring frequent outpatient visits to a specialized medical center due to tracheal devices. Many of these patients have mobility and cognition restrictions or require specialized transport due to the need for supplemental oxygen. This study describes the implementation and results of a telemedicine program dedicated to patients with central airway diseases based in a Brazilian public health system. Methods: A retrospective study of telemedicine consultation for patients with central airway diseases referred to a public academic hospital between August 1, 2020 and August 1, 2022. The consultations occurred in a telemedicine department using the hospital's proprietary platform. Data retrieved consisted of demographics, disease characteristics, and the treatment modalities of the patients. The analysis included the savings in kilometers not traveled, the carbon footprint based on reducing CO 2 emissions, and the cost savings in transportation. Results: A total of 1,153 telemedicine visits conducted in 516 patients (median age of 31.5 years). Two hundred ninety patients (56.2%) had a tracheal device (129 silicone T-Tube, 128 tracheostomy, and 33 endoprosthesis) and 159 patients (30.8%) had difficulties in transportation to the specialized medical center. Patients were served from 147 Brazilian cities from 22 states. The savings in kilometers traveled was 1,224,108.54 km, corresponding to a 250.14 ton reduction in CO 2 emissions. The costs savings in transportation for the municipalities was BRL$ 1,272,283.78. Conclusions: Telemedicine consultations for patients with central airway diseases are feasible and safe. Cost savings and the possibility of disseminating specialized care make telemedicine a fundamental tool in current medical practice.

Objectives: The Brazilian Society of Thoracic Surgeons conducted an online survey to determine the number of surgeons that perform adult and paediatric airway surgery and to understand the practice patterns along the country., Methods: Active members were electronically invited to complete the questionnaire through the REDCapR platform. Invitations were sent from January to April 2020. The survey encompassed 40 questions that explored 4 different topics in the assessment of tracheal diseases: (i) surgeon's demography; (ii) institutional profile, (iii) education and training in laryngo-tracheal surgery and (iv) preoperative and postoperative evaluation., Results: Eighty-nine percentage of the responders declared to perform tracheal surgery with a median of 5 tracheal resection procedures per year [interquartile range (IQR) 3-12]. Interaction with other specialties occurs in 37.3% of cases. Access to technology and devices is highly variable across the country. Resident training in airway surgery consists in traditional lectures in 97% of the cases. Training in animals (15.2%), cadavers (12.1%) and simulators (6.1%) are rare. Preoperatory evaluation encompasses flexible bronchoscopy (97.8%) and/or computed tomography (CT) scan of the airways (90.6%). Swallowing (20.1%) and voice (14.4%) disorders are rarely evaluated. Eighty-nine percentage of the surgeons consider bronchoscopy to be the preoperatory gold-standard exam, followed by CT scan (38.8%) and CT-3D reconstruction (37.4%)., Conclusions: Brazilian surgeons refer that airway resection and reconstruction are part of their current practice, but the total number of procedures per surgeon per year is low. Access to high-end technology and equipment is heterogenous. Training offered to residents in most academic institutions relies on traditional lectures., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.)

Timing of tracheostomy in patients with COVID-19 has attracted substantial attention. Initial guidelines recommended delaying or avoiding tracheostomy due to the potential for particle aerosolization and theoretical risk to providers. However, early tracheostomy could improve patient outcomes and alleviate resource shortages. This study compares outcomes in a diverse population of hospitalized COVID-19 patients who underwent tracheostomy either "early" (within 14 d of intubation) or "late" (more than 14 d after intubation)., Design: International multi-institute retrospective cohort study., Setting: Thirteen hospitals in Bolivia, Brazil, Spain, and the United States., Patients: Hospitalized patients with COVID-19 undergoing early or late tracheostomy between March 1, 2020, and March 31, 2021., Interventions: Not applicable., Measurements and Main Results: A total of 549 patients from 13 hospitals in four countries were included in the final analysis. Multivariable regression analysis showed that early tracheostomy was associated with a 12-day decrease in time on mechanical ventilation (95% CI, -16 to -8; p < 0.001). Further, ICU and hospital lengths of stay in patients undergoing early tracheostomy were 15 days (95% CI, -23 to -9 d; p < 0.001) and 22 days (95% CI, -31 to -12 d) shorter, respectively. In contrast, early tracheostomy patients experienced lower risk-adjusted survival at 30-day post-admission (hazard ratio, 3.0; 95% CI, 1.8-5.2). Differences in 90-day post-admission survival were not identified., Conclusions: COVID-19 patients undergoing tracheostomy within 14 days of intubation have reduced ventilator dependence as well as reduced lengths of stay. However, early tracheostomy patients experienced lower 30-day survival. Future efforts should identify patients most likely to benefit from early tracheostomy while accounting for location-specific capacity., Competing Interests: Dr. Harrell Shreckengost discloses financial support from the Lifebox Foundation as well as a Fogarty Global Health Fellowship. Dr. Nguyen discloses financial support from Prytime, Biomet, and Teleflex (honoraria for educational lectures). The remaining authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine.)

Mixed-valence ruthenium trinuclear clusters containing dichloroacetates were synthesized, and the self-assembly of a single molecular adlayer composed of these clusters on a graphite surface was investigated by atomic force microscopy (AFM). AFM clearly revealed the dynamics of two-dimensional (2D) structure formation as well as the molecular characteristics of the adlayers at different electrochemical interfaces. The results verified that the design of metal complexes is important not only for redox chemistry but also for molecular assembly and nanoarchitecture construction.

Blind-end stenosis (Myer-Cotton IV) is an extreme response to airway injury, resulting in phonatory ablation and dependence on a tracheostomy. A minimally invasive airway desobstruction and stenting can be beneficial in such cases. We present 2 cases of Myer-Cotton IV stenosis that were treated with a minimally invasive desobstruction using a hybrid (endoscopic-surgical) approach followed by the placement of a silicone T-tube., (Copyright © 2021 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Tracheal stenosis in children is a challenge for the healthcare team, since it is a rare disease. Patients usually have other clinical comorbidities, mainly previous cardiac surgical interventions. This retrospective single-center study included infants with tracheal stenosis (congenital or acquired) operated between 2016 and 2020 on venoarterial extracorporeal membrane oxygenation (VA ECMO). Five patients were operated and the median age of detection of the tracheal disease was 3.7 months, and the median age at the operation was 5 months. All patients had associated cardiac anomalies. Four patients had congenital tracheal stenosis; two with associated pig bronchus. One patient had acquired subglottic stenosis with concomitant stenosis at the carina. After the operation, the patients were referred to ICU on ECMO with an open chest. Minor ECMO-related complications occurred in two patients (hemothorax and wound infection). All patients required endoscopic evaluation during the postoperative care; median of 3.2 procedures. Two patients are currently in follow-up and three have died. Slide tracheoplasty with VA-ECMO can be successfully performed in infants with prior cardiac surgery. Nevertheless, a difficult postoperative course should be anticipated, with possible prolonged ECMO use, readmissions, and higher morbidity and mortality than in children with tracheal stenosis alone., (© 2020 International Center for Artificial Organs and Transplantation and Wiley Periodicals LLC.)

The COVID-19 Pandemic has resulted in a high number of hospital admissions and some of those patients need ventilatory support in intensive care units. The viral pneumonia secondary to Sars-cov-2 infection may lead to acute respiratory distress syndrome (ARDS) and longer mechanical ventilation needs, resulting in a higher demand for tracheostomies. Due to the high aerosolization potential of such procedure, and the associated risks of staff and envoirenment contamination, it is necesseray to develop a specific standardization of the of the whole process involving tracheostomies. This manuscript aims to demonstrate the main steps of the standardization created by a tracheostomy team in a tertiary hospital dedicated to providing care for patients with COVID-19.

Benign airway stenosis is a multifactorial and heterogeneous disease often occurring after tracheal intubation. Despite the frequent finding of pathological gastroesophageal reflux (GER) in benign tracheal stenosis, the cause-and-effect relationship between these two entities and its impact on the outcome of the stenosis itself have not been established. The altered ventilatory dynamics caused by an increased thoracoabdominal pressure gradient in such patients has been proposed as a central cause. The presence of GER in a setting of microaspiration can also induce changes in the local collagen proliferation response, as well as in the local microbiome of the tracheal stenosis site, which may potentially cause and enhance the harm imposed to the already diseased tracheal wall. Diagnosis of GER remains underestimated in the general population, thus making its accurate detection and treatment in central airway stenosis a matter of investigation. The high prevalence of GER in tracheal stenosis patients often occurs in the absence of typical upper digestive signs and symptoms, therefore requiring an objective assessment using a 24-hour ambulatory esophageal pH/impedance study that has shown abnormal results in more than half the patients. The impact of the treatment of GER in patients with benign tracheal has been scarcely reported. Our group showed recently that the surgical control of GER through laparoscopic fundoplication in selected patients with tracheal stenosis can improve substantially the chance of resolution of the tracheal stenosis as opposed to the medical management with high dose proton pump inhibitors. This chapter describes the impact of GER in the pathogenesis of tracheal stenosis with a focus on its mechanisms, diagnosis and treatment strategy., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/tcr.2020.03.24). The series “Recent Developments in Benign Tracheal Stenosis” was commissioned by the editorial office without any funding or sponsorship. BJB and PFGC served as the unpaid Guest Editors of the series. The authors have no other conflicts of interest to declare., (2020 Translational Cancer Research. All rights reserved.)

Objective: This study focuses on the impact of antireflux surgery in the outcome of tracheal stenosis., Methods: We performed a retrospective study including patients with benign tracheal stenosis who underwent esophageal manometry and dual-probe 24-hour ambulatory esophageal pH study. Patients with an abnormal pH study were managed with laparoscopic modified Nissen fundoplication or medically (omeprazole 80 mg/d, orally). Patients with normal pH study results were observed. After a 24-month follow-up, the outcome was considered satisfactory if tracheal stenosis could be managed by resection and there was no need for further dilatation or definitive decannulation. The management groups were compared using propensity score matching., Results: A total of 175 patients were included. Abnormal pH study results were found in 74 patients (42.3%), and 12.6% of patients had typical gastroesophageal reflux symptoms. Follow-up was completed in 124 patients (20 had fundoplication, 32 received omeprazole, and 72 were observed). After propensity score matching, the outcome of tracheal stenosis in the fundoplication group was similar to that of the observation group (odds ratio, 1; P = .99) and better than that of the omeprazole group (odds ratio, 5.31; P = .03). The observation (no gastroesophageal reflux) group had a better outcome of stenosis than those treated with omeprazole (odds ratio, 3.54; P = .02)., Conclusions: The outcome of the airway stenosis was superior after laparoscopic fundoplication compared with medical treatment with omeprazole and was similar to the outcome of patients without gastroesophageal reflux. A prospective randomized trial is warranted., (Copyright © 2019 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

To evaluate the feasibility of a 980-nm contact diode laser (CDL) as a method for creating a posterior laryngofissure in live pigs. Twenty-eight Landrace pigs (15-20 kg) were anesthetized, intubated, ventilated, and submitted to a cervical tracheostomy. An anterior and posterior midline longitudinal laryngofissure incision was created according to randomization-control (n = 4), posterior laryngofissure with a scalpel blade; electrocautery (n = 12), posterior laryngofissure by electrocautery (10, 15, 20, 25 W powers); CDL (n = 12), posterior laryngofissure by the CDL (10, 15, 20, 25 W peak powers in pulsed mode). Larynx and proximal trachea were excised, prepared for histopathology, and digital morphometric analysis. Measurements in and within each group were analyzed (Kruskal-Wallis and Dunn test) with a level of significance of p < 0.05. Incision width was not different between the groups, as well as in the powers used in CDL (p = 0.161) and electrocautery group (p = 0.319). The depth of the incisions was smaller in the Laser group compared to control (p = 0.007), and in the electrocautery compared to control (p = 0.026). Incision area was smaller in CDL compared with the control (p = 0.027), and not different between laser and electrocautery groups (p = 0.199). The lateral thermal damage produced by electrocautery was the largest, with a significant difference between laser and electrocautery (p = 0.018), and between electrocautery and control (p = 0.004), whereas the comparison between laser and control showed no significant differences (p = 0.588). The posterior laryngofissure incision using a 980-nm CDL is feasible resulting in smaller incisional area and less lateral thermal damage.

Background: The primary objective of the study was to evaluate the health-related quality of life (HRQL) of patients with benign post-intubation tracheal stenosis considered as unfit for surgical treatment. Secondary objectives were: (I) to determine if clinical variables (gender, age, total treatment time, and type of tracheal device) could influence HRQL and (II) to compare the results with a normal standardized population., Methods: Prospective study between August-2014 and December-2016 including patients with tracheal stenosis treated with silicone stents, T-Tubes or tracheostomy. Candidates to airway resection and reconstruction were excluded from the analysis. HRQL was assessed with the SF-36 Health Questionnaire. Backward stepwise regression model analyzed the influence of clinical variables on the SF-36 domains and component summaries. Norm-based results were compared with normative data. Alpha error was 5%., Results: Ninety-three patients (62M/31F; mean age 38±14 years) were included. Mean overall HRQL in all 8 SF-36 domains was poor. Lowest scores were in the role physical (mean 31.7±38), bodily pain (mean 39.2±35), and role emotional domain (mean 48.7±40). The physical component summary (PCS) was more affected than the mental (P<0.001). Norm-based results indicated that most domains and both physical and mental summaries were below the mean for the USA normative population. Total stenting time significantly influenced the physical (P=0.001) and mental component summaries (P=0.001)., Conclusions: Quality of life of patients with benign tracheal stenosis is severely impaired, and norm-based results indicate that the HRQL is below normative data. Physical and mental discomfort seems to be attenuated by total treatment time., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Benign tracheoesophageal fistula (TEF) results from an abnormal communication between the posterior wall of the trachea or bronchi and the adjacent anterior wall of the esophagus. It can be acquired or congenital. The onset of the TEF has a negative impact on the patient's health status and quality of life because of swallowing difficulties, recurrent aspiration pneumonia, and severe weight loss. Several acquired conditions may cause TEF. The most frequent is prolonged orotracheal intubation (75% of the cases). Usually, there is an erosion of the tracheal and esophageal wall by the continuous pressure between the endotracheal tube and the esophageal wall; particularly in the presence of a nasogastric or feeding tube within the esophageal lumen. Furthermore, tracheal stenosis is often associated, and adds complexity to the disease. Preparation for the surgical procedure may take weeks or even months. It includes definitive weaning from mechanical ventilation, treatment of respiratory infection, physiotherapy, and correction of malnutrition through enteral feeding. Surgical repair of a TEF is an elective procedure. It consists of division of the fistula, suture of the esophagus and trachea and protection of the suture lines with a buttressed muscle flap. TEF repair is a complex and challenging procedure, thus, high morbidity and mortality are expected. Nonetheless, surgical management yields excellent long-term results, and it should be considered the first-line treatment for this condition. Definitive fistula closure occurs in about 90-95% of the cases., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Tracheal resections are major surgical procedures with a complication rate as high as 44%. Early detection of complications followed by a structured and expedited course of action is critical for achieving a successful outcome. The prevention of complications after tracheal resection starts with a correct indication for resection. A thorough preoperative evaluation, meticulous surgical technique, and good postoperative care in a center that performs airway surgery routinely are important factors for achieving good results., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objectives: Bronchopleural fistula (BPF) is an uncommon complication following a lung resection to address various conditions. BPFs are associated with high morbidity and mortality rates. This study evaluated the endoscopic treatment of 'total' BPFs using the Occlutech-Fígulla® cardiac device at a single centre., Methods: We selected nine patients with chronic and complete BPFs. Under direct bronchoscopic visualization, the BPFs were treated using the Occlutech-Fígulla device. The patients were followed up for 12 months to determine the treatment level and complications., Results: The procedure had a favourable outcome in three patients, resulting in complete fistula closure. Two patients had partial closure and showed improvements in their clinical conditions. In two other cases, closure of the bronchial stump was unsuccessful using this method. Two patients died from causes unrelated to the procedure or the device. During the follow-up period, no complications related to infection or device-related injuries were reported., Conclusions: In patients without clinical conditions that require surgical treatment, the Occlutech-Fígulla cardiac device can be a safe and effective method for the endoscopic treatment of large BPFs resulting from complete dehiscence of a bronchial stump. No severe events were reported., (© The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: Benign tracheoesophageal fistulas (TEFs) are rare, and surgical correction is the ideal method of treatment. The objective of this study was to evaluate the results of operative treatment of benign TEFs in patients from a tertiary referral center., Methods: Retrospective study of patients with benign TEFs who were treated between January 2005 and December 2014. Preoperative evaluation included computed tomography of the chest, bronchoscopy, and upper endoscopy. Preoperative treatment included nutritional support by gastrostomy and treatment of lung infections. Surgical repair was done with tracheal resection and reconstruction, laryngotracheal resection, or membranous tracheal repair without resection. Esophageal management consisted of two-layer closure., Results: Twenty patients (11 men) with mean age 48 ± 17 years were included. The most frequent cause was postintubation injury (n = 16; 80%). The median TEF length was 9 mm (interquartile range [IQR], 2 to 25 mm). The most commonly used surgical approaches were cervicotomy (n = 15; 75%) and cervicosternotomy (n = 3; 15%). Eleven patients required tracheal resection; median length was 3 cm (IQR, 3 to 5.5 cm). Seven patients (35%) required intraoperative tracheostomy. Complications occurred in 55% of patients. There was one dehiscence of the tracheal anastomosis, and one procedure-related death. Ninety-five percent of patients had complete closure of the TEF occurred in 95% of cases. Two patients had tracheal stenosis recurrence, and one patient had both TEF and tracheal stenosis recurrence. Two patients have indwelling silicone tracheal stents., Conclusions: Surgical treatment of TEF is effective. Nonetheless, morbidity and mortality are not negligible, even when performed at a referral center and after appropriate preoperative evaluation., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Airway complications after lung transplantation are the major cause of morbidity, affecting up to 33% of all cases. Bronchial stenosis is the most common complication. The use of stents has been established as the most effective therapy; however, their removal is recommended after 3-6 months of use. We have been using self-expandable stents as a definitive treatment and remove them only if necessary. For this report, we evaluated the use of self-expandable stents as a definitive treatment for bronchial stenosis after lung transplantation., Methods: We performed a retrospective cohort study to evaluate patients with bronchial stenosis from August 2003 to April 2014. Clinical and pulmonary function test data were collected., Results: Two hundred lung transplants were performed, 156 of which were bilateral. Sixteen patients experienced airway complications: 4 had dehiscence, 2 necrosis, and 10 bronchial stenosis. Of these patients, 7 had undergone bilateral procedures, and 2 patients developed stenosis in both sides. Twelve anastomotic stenoses were observed. The follow-up after stenting ranged from 1 to 7 years. All patients had increased lung function, and 4 remained stable with sustained increase in pulmonary function without episodes of infection. Three patients required removal of their prosthesis 6 months to 1 year after implantation because of complications. Two patients died owing to unrelated causes., Conclusions: Definitive treatment of bronchial stenosis with self-expandable stents is a viable option. The 1st year seems to be the most crucial for determining definitive treatment, because no patients required removal of their stent after 1 year., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Tracheal resection and anastomosis is the gold standard for the treatment of tracheal stenosis. The objective of this study is to evaluate the complications after tracheal resection for benign stenosis and the predicting factors for such complications., Methods: A retrospective study was made involving patients with benign tracheal or laryngotracheal stenosis who underwent surgical resection and reconstruction between February 2002 and January 2009. Complications related and unrelated to the anastomosis were studied. Categorical variables were presented as percentage and continuous variables as mean and standard deviation. Predicting factors were determined by univariate analysis. Factors with p less than 0.05 were used for multivariate regression. Logistic regression models were also employed for dependent variables. Statistical significance was set for p less than 0.05., Results: Ninety-four patients (18 female, 76 male) were included. Complications occurred in 42 (44.6%). Twenty-one percent had anastomotic complications. The most common complication was restenosis (16%). Nonanastomotic complications occurred in 23.2%. Wound infection occurred in 10.6%. Clinical comorbidities, previous tracheal resection, and the length of tracheal resection were statistically significant factors for complications. Previous tracheal resection was the most significant factor and was highly associated with anastomotic complications (odds ratio 49.965, p=0.012). The greatest number of complications was found in the laryngotracheal reconstruction group, and in resections more than 4 cm. Mean follow-up was 19±14 months. At the end of the study, 86 patients (91.4%) were breathing normally. There was no mortality in this series., Conclusions: Comorbidities, previous tracheal resection, and the length of tracheal resection more than 4 cm were statistically significant factors for the onset of complications., (Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: Right main bronchial anatomy knowledge is essential to guide endoscopic stent placement in modern era. The aim is to describe right bronchial anatomy, cross-area and its relation with the right pulmonary artery and patient's age., Methods: One hundred thirty four cadaveric specimens were studied after approval by the Research and Ethics Committee at the University of São Paulo Medical School and Medical Forensic Institute of São Paulo. All necropsies were performed in natura after 24 hours of death and patients with previous pulmonary disease were excluded. Landmarks to start measurement were the first tracheal ring, vertex of carina, first right bronchial ring, and right pulmonary artery area over the right main bronchus. After mobilization, the specimens were measured using a caliper and measurement of distances was recorded in centimeters at landmarks points. All the measures (distances, cross sectional area and planes) were performed by three independent observers and recorded as mean, standard error and ranges. Student t test was used to compare means and linear regression was applied to correlate the measurements., Results: From 134 specimens studied, 34 were excluded (10 with previous history of pulmonary diseases, surgery or deformities and 24 of female gender). Linear regression showed proportionality between tracheal length and right bronchus length; with the area at first tracheal ring and carina and also between the cross sectional area at these points. Linear regression analysis between tracheal length and age (R=0.593 P<0.005), right bronchus length and age (R=0.523, P<0.005), area of contact between right bronchus and right pulmonary artery and age (R=0.35, P<0.005)., Conclusions: We can conclude that large airways grow progressively with increasing age in male gender. There was a direct correlation between age and tracheal length; as has age and right bronchus length. There was a direct correlation between age and the area of the right bronchus covered by the right pulmonary artery.

Background: Decannulation is the ultimate therapeutic goal for patients who undergo stenting because of inoperable benign tracheal stenosis. In this study, our objectives were to evaluate whether long-term airway stenting allows decannulation in patients with benign tracheal stenosis who were deemed inoperable and to identify possible predictive factors for successful decannulation (SD)., Methods: Retrospective cohort study including all patients with inoperable benign tracheal stenosis who underwent tracheal stenting in our tertiary-care university-based institution from 1998 to 2008. For benign stenosis, we use only silicone stents (T tubes, Dumon stents, and Y stents). The main outcome was SD, which was defined as removal of the tracheal stent followed by absence of respiratory symptoms and no requirement for new dilation procedures for at least 6 months. A Kaplan-Meier curve was built to evaluate SD in 5 years, and we used a Cox model to evaluate predictors for a SD., Results: Ninety-two patients were included, and during the study period 21 were decannulated. However, 2 of them had to undergo new airway procedures and were considered to represent failure. Therefore, 19 patients were successfully decannulated. According to the Kaplan-Meier estimate, the SD rate in 5 years was 27.5%. The mean follow-up time after SD was 34.3 ± 33.9 months (range, 6 to 108 months). Cox regression showed only 1 significant factor: tracheostomy before stent insertion caused a threefold increase in the likelihood of the patient remaining with a tracheal stent (p = 0.048)., Conclusions: Tracheal stenting may be considered a curative therapeutic approach in as many as 27.5% of patients with inoperable benign tracheal stenosis., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the compatibility of a new model of self-expandable tracheal stent in rats., Methods: A new device of polyurethane covered and non - covered stent was placed in the trachea of Wistar rats. Animals were distributed in two groups: the polyurethane covered and non-covered group. Macroscopic parameters included position within the tracheal lumen, adherence to the mucosa, degree of dilatation, permeability and internal diameter. Microscopic findings evaluated were: incorporation, inflammatory activity, granulation tissue and epithelial revetment injuries. The observation follow-up was six weeks. All parameters were quantified based on determined score values. Incorporation of the stents was evaluated based on the observation if the stent was fixed into the trachea or if it could be removed. Degree of dilatation was performed by external diameter measurements. Granulation tissue was evaluated by measurements of height of the tissue growing into the tracheal lumen., Results: 100% of non-covered stents had total attachment to mucosa and 100% of polyurethane covered type had adherence only. Regarding dilatation, granulation tissue, inflammatory activity and internal diameter measurements, there were no significant differences between the groups. Pathological tracheal wall injuries were present in both groups., Conclusion: Both models of stent demonstrated biocompatibility with the trachea. Rats are suitable for an experimental model of tracheal stent study.

We aimed to test a new model of self-expanding tracheal stent so that it might be made available for clinical use. Using direct laryngoscopy, we placed polyurethane-coated, nitinol stents into the middle third of the trachea in 25 New Zealand rabbits. After a mean observation period of 26 days, we evaluated stent migration, degree of expansion, attachment, adherence, formation of granulation tissue, presence of inflammatory infiltrate, parietal involvement, and epithelial lining. The results showed complete radial expansion, little adherence to the tracheal mucosa, and low tissue attachment, as well as high rates of granuloma formation and stent migration. This new model proved to be biocompatible and showed a behavior similar to that of other stents on the market.

Objective: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a new method for the diagnosis and staging of mediastinal lymph nodes. The objective of this study was to evaluate the preliminary results obtained with EBUS-TBNA in the diagnosis of lesions and mediastinal lymph node staging., Methods: We evaluated patients with tumors or mediastinal adenopathy, diagnosed with or suspected of having lung cancer. The procedures were performed with the patients under sedation or under general anesthesia. Material was collected by EBUS-TBNA, after which it was prepared on slides, fixed in either absolute alcohol (for cytology) or formalin (for cell-block analysis)., Results: We included 50 patients (30 males). The mean age was 58.3 ± 13.5 years. We performed 201 biopsies of 81 lymph nodes or mediastinal masses (mean of 2.5 punctures/biopsy). The quantity of material was considered sufficient for cytology in 37 patients (74%), 21 (57%) of whom were thus diagnosed with malignancy. Of the remaining 16 patients, 1 was diagnosed with tuberculosis, 6 entered clinical follow-up, and 9 underwent further investigation (2 diagnosed with neoplasm-false-negative results). The yield was higher when the procedure was performed for diagnostic purposes, as well as being higher in patients with lesions in multiple stations and in biopsies involving the subcarinal lymph node station. One patient had endobronchial bleeding, which was resolved with local measures. There were no deaths among the patients evaluated., Conclusions: This preliminary experience shows that EBUS-TBNA is a safe procedure. Our diagnostic yield, although lower than that reported in the literature, was consistent with the learning curve for the method.

Suspension laryngoscopy is one of the most common otolaryngological procedures for the diagnosis and surgical approach to the larynx. However, most thoracic surgeons are not familiar with the procedure and seldom use it. The indications for its use are similar to those for that of rigid bronchoscopy (dilatation, endoprosthesis insertion, and tumor resection). It can be performed in children and adults. Suspension laryngoscopy is an alternative when rigid bronchoscopy is unavailable and is therefore a viable option for use at smaller facilities. In this communication, we describe the technique and the applications of suspension laryngoscopy in thoracic surgery.

Fistulas in the tracheobronchial tree (bronchopleural and tracheoesophageal fistulas) have a multifactorial etiology and present a variable incidence in the literature. In general, the related morbidity and mortality are high. Once such a fistula has been diagnosed, surgical closure is formally indicated. However, the clinical status of affected patients is usually unfavorable, which precludes the use of additional, extensive surgical interventions. In addition, attempts at endoscopic closure of these fistulas have seldom been successful, especially when the fistula is large in diameter. We report the cases of three patients submitted to endoscopic closure of fistulas, two of which were larger than 10 mm in diameter, by means of the insertion of atrial septal defect occluders. The procedure was minimally invasive, and the initial results were positive. The results indicate that this is a promising technique for the resolution of tracheobronchial tree fistulas.

Bronchopleural fistula may be treated by medical, endoscopic, and surgical techniques, but large fistulas remain a challenge to be closed using endoscopic techniques. We describe the endoscopic closure of a bronchial total fistula with the Occlutech Figulla ASD N device (International Occlutech AB, Helsingborg, Sweden), originally designed for closure of an atrial septal defect. The procedure was conducted without general anesthesia or rigid bronchoscopy, bronchography, or radioscopy. An immediate reduction in the air leak was observed and also later on bronchoscopy, as the device was almost covered by granulation tissue. The endobronchial technique described seems to be safe and effective to manage large bronchopleural fistulas.