Interventional management of tracheobronchial strictures

Tracheobronchial balloon dilation and stent placement have been well used in the treatment of patients with benign and/or malignant diseases.Balloon dilation is the first option in the treatment of benign airway stenosis.Although balloon dilation is simple and fast,recurrence rate is high.Stent placement promptly relieves acute airway distress from malignant extraluminal and intraluminal airway obstruction.Temporary stent placement may be an alternative for benign airway strictures refractory to balloon dilation.This article reviews the indications,pre-procedure evaluation,technique,outcomes and complications of balloon dilation and stent placement with regard to benign and malignant tracheobronchial stenoses.

Key determinants of misdiagnosis of tracheobronchial tuberculosis among senile patients in contemporary clinical practice:A retrospective analysis

BACKGROUND Tracheobronchial tuberculosis(TBTB)is a common subtype of pulmonary tuberculosis.Concomitant diseases often obscure the diagnosis of senile TBTB.AIM To characterize senile patients with TBTB and to identify the potential causes of misdiagnosis.METHODS One hundred twenty patients with senile TBTB who were admitted to the Anhui Chest hospital between May 2017 and May 2019 were retrospectively analyzed.Patients were classified as diagnosed group(n=58)and misdiagnosed group(n=62).Clinical manifestations,laboratory results,radiographic data,and endoscopic findings were compared between the two groups.RESULTS Patients in the misdiagnosed group were most commonly diagnosed as pulmonary tuberculosis(non-TBTB,29/62,46.8%),general pneumonia(9/62,14.5%),chronic obstructive pulmonary disease(8/62,12.9%),and tracheobronchial carcinoma(7/62,11.3%).The time elapsed between disease onset and confirmation of diagnosis was significantly longer in the misdiagnosed group[median(first quartile,third quartile):6.32(4.94,16.02)mo vs 3.73(2.37,8.52)mo].The misdiagnosed group had lower proportion of patients who underwent bronchoscopy[33.87%(21/62)vs 87.93%(51/58)],chest computed tomography(CT)scan[69.35%(43/62)vs 98.28%(57/58)],and those who showed CT signs of tuberculosis[27.91%(12/62)vs 50%(29/58)]as compared to that in the diagnosed group(P<0.05).There were no significant between-group differences with respect to age,gender,occupation,clinical manifestations,or prevalence of comorbid chronic diseases(P>0.05).CONCLUSION Insufficient or inaccurate radiographic or bronchoscopic assessment was the predominant cause of delayed diagnosis of TBTB.Increased implementation and better interpretation of CT scan and early implementation of bronchoscopy can help reduce misdiagnosis of senile TBTB.

Primary Tracheobronchial Amyloidosis in China:Analysis of 64 Cases and A Review of Literature

Primary tracheobronchial amyloidosis (TBA) is a rare pulmonary disease.A systematic review was performed on 64 cases of primary TBA in China and progress in the diagnosis and treatment of this disease is discussed.The Chinese biological and medical databases from 1970 to 2010 were searched and 75 cases of complete clinical and pathological data were identified.The clinical characteristics of the disease were summarized and longitudinal comparisons were made of diagnostic and treatment methods over time.The results showed that the morbidity associated with primary TBA has increased over recent years.The clinical manifestations were non-specific.Progressive dyspnea, cough and sputum were the most common symptoms.The percentage of patients undergoing computed tomography (CT) scan has increased over the years.The bronchoscopy and transbrochial lung biopsy (TBLB) were usually sufficient to establish the diagnosis.Treatment was reported for a total of 44 cases.Bronchoscopic Nd:YAG laser irradiation, argon plasma coagulation (APC) and drugs administration such as steroids and colchicines were reported to be effective in some patients.It is concluded that the demographic characteristics and clinical manifestations of primary TBA patients in China are largely consistent with findings reported in other countries.Dramatically more cases were reported in recent years, mainly due to the extensive application of bronchoscopy since 1990s.Chest CT scan provides important clues for the diagnosis of the disease.The definite diagnosis was confirmed by bronchoscopic findings and Congo red staining of biopsy specimen.Bronchoscopic Nd:YAG laser irradiation, argon plasma coagulation (APC) and drugs administration, such as steroids and colchicines were reported to be effective in some patients.

Clinical Analysis of Primary Tracheobronchial Tumors in Children and Evaluation of the Predicting Models for Mucoepidermoid Carcinoma

Objective:To determine the clinical characteristics and prognosis of primary tracheobronchial tumors(PTTs)in children,and to explore the most common tumor identification methods.Methods:The medical records of children with PTTs who were hospitalized at the Children's Hospital of Chongqing Medical University from January 1995 to January 2020 were reviewed retrospectively.The clinical features,imaging,treatments,and outcomes of these patients were statistically analyzed.Machine learning techniques such as Gaussian na?ve Bayes,support vector machine(SVM)and decision tree models were used to identify mucoepidermoid carcinoma(ME).Results:A total of 16 children were hospitalized with PTTs during the study period.This included 5(31.3%)children with ME,3(18.8%)children with inflammatory myofibroblastic tumors(IMT),2 children(12.5%)with sarcomas,2(12.5%)children with papillomatosis and 1 child(6.3%)each with carcinoid carcinoma,adenoid cystic carcinoma(ACC),hemangioma,and schwannoma,respectively.ME was the most common tumor type and amongst the 3 ME recognition methods,the SVM model showed the best performance.The main clinical symptoms of PPTs were cough(81.3%),breathlessness(50%),wheezing(43.8%),progressive dyspnea(37.5%),hemoptysis(37.5%),and fever(25%).Of the 16 patients,7 were treated with surgery,8 underwent bronchoscopic tumor resection,and 1 child died.Of the 11 other children,3 experienced recurrence,and the last 8 remained disease-free.No deaths were observed during the follow-up period.Conclusion:PTT are very rare in children and the highest percentage of cases is due to ME.The SVM model was highly accurate in identifying ME.Chest CT and bronchoscopy can effectively diagnose PTTs.Surgery and bronchoscopic intervention can both achieve good clinical results and the prognosis of the 11 children that were followed up was good.

Effects of Retinoic Acid on the β-catenin/TCF Pathway in Cultured Porcine Tracheobronchial Epithelial Cells

The effects of retinoic acid on the β-catenin/TCF pathway in cultured porcine tracheobronchial epithelial cells (TBEC) were investigated. After TBEC were treated with retinoic acid at various concentrations, mRNA and protein changes of β-catenin in cytoplasm, nucleus and whole cell of the TBEC were observed by immunocytochemical stain, RT-PCR and Western blotting. And the changes of the target gene cyclinD1 of β-catenin/TCF pathway were also observed. It was found that there was no significant difference in β-cat mRNA level after retinoic acid treatment. However, the expression of β-catenin in the whole cell and cytoplasm was elevated with the increase of retinoic acid concentration (P<0.01). The nuclear protein β-catenin and target gene cyclinD1 of β-catenin/TCF pathway was decreased (P<0.05). It was indicated that retinoic acid could increase β-catenin level of the whole cell protein and decrease nuclear β-catenin, downregulating β-cat/TCF signaling activity and reducing target gene cyclinD1 protein level. As a result, retinoic acid can downregulate β-catenin/TCF pathway in porcine tracheobronchial epithelial cell, suggesting that retinoic acid can inhibit the proliferation and accelerate differentiation of tracheobronchial epithelial cells.

Relapsing polychondritis with isolated tracheobronchial involvement complicated with Sjogren's syndrome:A case report

BACKGROUNDRelapsing polychondritis (RP) is a rare, long-term, and potentially life-threateningdisease characterised by recurrent paroxysmal inflammation that can involve anddestroy the cartilage of the external ear, nose, larynx, and trachea.CASE SUMMARYWe here report a case of RP involving solely the tracheobronchial cartilage ring(and not the auricular. nasal or articular cartilage) complicated by Sjögren's syndrome in a 47-year-old female whose delayed diagnosis caused a sharpdecline in pulmonary function. After corticosteroid treatment, her pulmonaryfunction improved.CONCLUSIONIn such cases, our experience suggested that 18F-fluorodeoxyglucose positronemission tomography/computed tomography (18F-FDG PET/CT) and fiberopticbronchoscopy should be used to diagnose airway chondritis as relapsing polychondritisin the early phase of disease.

Surgical treatment of primary tracheobronchial malignant tumors

Objective： The aim of our study was to explore the clinical experience of surgical treatment for primary tracheobronchial malignant tumors. Methods： The clinicopathological data of 18 patients with primary tracheobronchial malignant tumors surgically treated from February 1994 to August 2007 were reviewed retrospectively. The surgical management included sleeve tracheal resection in 8 cases, lower trachea and carina resection with carina reconstruction in 4 cases, local enucleation of the tumor in 4 cases, left or right carino-pneumon-ection in 2 cases, and resection of the tracheal or bronchial tumor and reconstruction of the airway under cardiopulmonary bypass （CPB）in 6 cases. Results： Among the 18 cases, there were 7 adenoid cystic carcinomas, 9 squamous cell carcinomas, 1 lymphoepithelial-like carcinoma and 1 follicular non-Hodgkin tymphoma. All the cases recovered well except one who died of endotracheal bleeding and asphyxia at the 10th postoperative day. Conclusion： Surgical resection is the most effective treatment for primary tracheobronchial malignant tumors. The selection of operation modes should be individualized according to patients＇ condition. Both complete resection and safety should be taken into consideration simultaneously.

Is Primary Repair of Tracheobronchial Rupture Curative?

Background: Tracheobronchial disruption as a result of blunt thoracic trauma is a rare entity and only clinically serious lesions come to our notice, which can be life-threatening and need prompt recognition and treatment. Objectives: To review the authors’ experience with tracheobronchial injuries to emphasize the need for prompt diagnosis and treatment to avoid lethal complications including severe hypoxic organ failure, sepsis, mediastinitis and bronchopleural fistula. Patients and methods: A retrospective study of total 32 patients with tracheobronchial injury from 2001 to 2011. This study limited to patients with thoracic tracheal or bronchial injury, excluding those with cervical injuries. The study includes collected information about mechanism of injury, presentation, time until diagnosis and treatment, anatomical site of injury, type of treatment, diagnostic methods, duration of follow up and outcome. Results: Twenty-four patients were male (75%) and eight were females (25%). Patient’s ages ranged from 7 - 53 years. Majority of cases was referred because of blunt trauma in 15 cases (46.8%), 6 (18.75) motor vehicle accident, 5 (15.6%) fall from a height and 4 (12.5%) with trauma by heavy object, while 8 cases (25%) were referred due to penetrating injury and 2 cases (6.25%) due to iatrogenic injury. In initially diagnosed group, the predominant clinical signs that give a suspicion of tracheobronchial disruption were increased subcutaneous surgical emphysema, shortness of breath, hemoptysis. After the admission to emergency unit, all of them were examined radiologically by chest X-ray film. Longitudinal tear of right upper lobe bronchus was found in 8 cases (32%), complete cut of right upper lobe bronchus in 4 cases (16%), tear of right intermediate bronchus in 4 cases (16%), 3 cases with clear cut left upper lobe (12%), longitudinal tear of distal lateral tracheal wall extend to right upper lobe in 2 cases (8%), 2 cases (8%) showed complex disruption of distal trachea right main with carinal tear and 2 cases (8%) with longitudinal tear of membranous wall of the trachea. 17 patients from early diagnosed cases had concomitant comorbid extra thoracic injuries at the time of diagnosis in the form of abdominal trauma in 12 cases, skeletal fractures in 9 cases and head injury in 5 cases. Conclusion: In a patient with a complex bronchial rupture, primary repair of the bronchus can be possible with complete functional preservation of the lung tissue.

Primary experience of video-assisted rigid laser bronchoscopy in treatment of tracheobronchial tumors

To review the primary experience of video-assisted rigid laser bronchoscopy in the treatment of tracheobronchial tumors.Methods From Sep.2002 to Nov.2004,13 patients (15 procedures) with tracheobronchial tumors were treated with video-assisted rigid bronchoscope.Benign tumors with small pedicles were removed directly.For benign tumors with wide pedicles or tumors extending beyond the wall of air-way,total enucleating through thoracotomy were employed.In cases with malignant tumors,stenosis or obstructions were relieved by implantation of stent or cautering with electric argoulaser knife.For malignant but resectable primary tumors of trachea and main bronchi,rigid bronchoscopy might serve as a preparation of radical resection.Results Of the 5 patients with benign tumors,4 received endoscopic total resection and 1 were conversed into thoracotomy.For the 8 malignant cases,3 received stent implantation,2 had palliative ablation 3 got curative resections through thoracotomy.No peri-operative complications or death occurred in this group.Conclusion Total resection of benign tracheobronchial tumors or palliative therapy for tracheobronchial malignant stenosis or preparation of radical resection can be performed safely and efficiently by video-assisted rigid bronchoscopy.5 refs.

Flexible bronchoscopy for foreign body aspiration in children:A single-centre experience

BACKGROUND The technological evolution of bronchoscopy has led to the widespread adoption of flexible techniques and their use for both diagnostic and therapeutic purposes.Currently,there is an active debate regarding the comparative efficacy and safety of rigid vs flexible bronchoscopy in the treatment of foreign body aspiration.AIM To evaluate our experience with tracheobronchial foreign body extraction using flexible bronchoscopy and provide a literature overview.METHODS This was a single-centre retrospective study.Twenty-four patients were enrolled between January 2017 and January 2023.Medical records of patients aged below 18 years who were admitted to authors’affiliated institution with a suspected diagnosis of foreign body aspiration were collected from hospital’s database to Microsoft Excel 2019.Data were analysed using MedCalc Statistical Software.RESULTS Patient ages varied from 9 months to 11 years.The median age was 23.5 months,95%confidence interval(CI)19.49-44.77.We observed age clustering in children with foreign body aspiration at our institution with three age subgroups:(1)0-25 months;(2)40-60 months;and(3)120-140 months.We expectancy of an organic tracheobronchial foreign body was significantly higher in 0-25 months subgroup than that in older ones when subgroups 40-60 and 120-140 months were combined together(odds ratio=10.0,95%CI:1.44-29.26,P=0.0197).Successful foreign body extraction was performed in all cases.Conversion to a rigid bronchoscope was not required in any of the cases.No major complications(massive bleeding,tracheobronchial tree perforation,or asphyxia)were observed.CONCLUSION Flexible bronchoscopy is an effective and safe method for tracheobronchial foreign body extraction in children.

Pseudomembranous necrotizing tracheobronchial aspergillosis： an analysis of 16 cases

Background In our clinical practice we have been attracted by a group of patients with airway aspergillosis who have airway obstruction; we termed the condition as pseudomembranous necrotizing tracheobronchial aspergillosis （PNTA）. In this study we analyzed the clinical data from patients with PNTA, so as to guide the diagnosis and treatment of the disease. Methods A total of 16 PNTA patients were treated in Changhai Hospital from January 2000 clinical data, including the demographic information, clinical symptoms, imaging findings treatment strategies and efficacy, and prognosis, were retrospectively analyzed. to January 2009. Their bronchoscopy findings, Results All 16 patients were found to have primary systemic immunodeficiency diseases and/or damage of the focal airways. Nine patients （9/16, 56.3%） had pulmonary and tracheobronchial tumors, 5/16 （31.3%） had tracheobronchial involvement secondary to non-pulmonary tumors, and 2/16 （12.5%） had lung transplantation. The most common causes of PNTA included local radiotherapy （10/16, 62.5%）, repeated chemotherapy （7/16, 43.8%） and recurrent intervention therapy by bronchoscope （4/16, 25.0%）. Aspergillus fumigatus was the most frequent pathogen （62.5%, 10/16）. The main clinical manifestations included progressive dyspnea （14/16, 87.5%） and irritable cough （12/16, 75.0%）. The trachea was involved in 9/16 patients （56.3%）, right main bronchus in 10/16 （62.5%）. All 16 patients were treated with systemic anti-aspergillosis agents, local anti-aspergillosis agents with amphotericin B inhalation and direct perfusion of amphotericin B by bronchoscope, and interventional treatment by bronchoscope to ensure an unobstructed airway. The total efficiency was 31.3%. Conclusions PNTA is an infectious disease caused by aspergillus and it mainly involves the trachea, primary bronchus and segmental bronchus. A. fumigatus is the most common pathogen. PNTA can pose a severe clinical threat and often occurs after systemic immunodeficiency and/or local airway damage, with the main symptoms including dyspnea and irritable cough. Bronchoscopic findings supply the main evidence for diagnosis of PNTA. Treatment of PNTA is difficult and requires a long course. Systemic and local anti-aspergillosis agents plus bronchoscopy debridement can improve the prognosis of the disease.

In vitro degradation and biocompatibility evaluation of typical biodegradable metals (Mg/Zn/Fe) for the application of tracheobronchial stenosis

Tracheobronchial obstruction in children due to benign stenosis or tracheobronchomalacia still remains a challenging matter of concern.Currently,there is 10%–20%complication rate in clinical treatment.The nonbiodegradable property of silicone stents and nickel-titanium memory alloy stents take the primary responsibility for drawbacks including stimulating local granulation tissue proliferation,displacement,and stent-related infections.Permanent tracheobronchial stent will be a persistent foreign object for a long time,causing excessive secretion of tracheal mucosa,ulceration and even perforation,which is particularly unsuitable for young children with persistent tracheal growth.In this study,the degradation and biocompatibility performance of three typical biodegradable metals were investigated as potential tracheobronchial stent materials.The results exhibited that these materials showed different degradation behaviors in the simulating respiratory fluid environment compared with SBF.Except for pure iron group,high purity magnesium and zinc showed favorable cell adhesion and proliferation in three culture methodologies(direct culture,indirect culture and extraction culture).The proper corrosion rate and good biocompatibility indicated that high purity magnesium and zinc may be good candidates as tracheobronchial stent materials.

Radial probe endobronchial ultrasound scanning assessing invasive depth of central lesions in tracheobronchial wall

Background Patients with central tracheobronchial benign or malignant lesions who have not recieved surgical treatment can be treated by interventional techniques, such as laser, afterloading radiotherapy, cryotherapy, photodynamics treatment, radiofrequency ablation and stenting, etc. The accuracy of the invasive depth of central lesion in tracheobronchial wall plays an important role in making interventional treatment plan. This study used radial probe endobronchial ultrasound （RP-EBUS） scanning to evaluate the accuracy of the invasive depth of central lesions in tracheobronchial wall, and the influence of RP-EBUS scanning in treatment plan making and guidance. Methods This was a prospective study of consecutive patients with central tracheobronchial lesions found by CT or bronchoscopy. We performed EBUS scanning after common bronchoscopy under local anesthesia. A radial ultrasonic probe （2.0 mm in diameter with 20-MHz frequency） with a balloon sheath was introduced through the 2.8-mm-diameter channel of a flexible bronchoscope. The balloon at the tip of the probe was inflated with distilled water until coupling with the airway wall under endoscopic control. The circular image of EBUS, which revealed the layered structure of the tracheobronchial wall, could be achieved. Results Total of 125 patients were enrolled in the study. Thirty patients underwent surgical operation and pathologically proved the RP-EBUS diagnosis accuracy of tumor invasive depth in tracheobroncial wall was 90% （27/30）, sensitivity and specificity were 88.89% （24/27） and 100% （3/3）, respectively. In response to EBUS images, 40 approaches were altered or guided： lymph-node metastasis and compressive lesions was diagnosed by EBUS-guided transbronchial needle aspiration （TBNA） （n=8）; Lesions ablation with laser or electricity were stopped when EBUS demonstrated close range with vessels or perforation possibility （n=13）, stents size were changed （n=14）, operation was canceled （n=3） and foreign body was removed （n=2）. No complication associated with the use of EBUS was observed. Conclusion RP-EBUS can be a useful tool in assessing the central lesion invasive depth to the tracheobronchial wall.

Multi-detector computed tomography evaluation of tracheobronchial anomaly in pediatric patients with left pulmonary artery sling

The left pulmonary artery sling （LPAS） is a rare vascular anomaly causing respiratory distress in which theleft pulmonary artery arises from the posterior aspect of the right pulmonary artery, courses posteriorly to the right of the bronchus and passes between the trachea and oesophagus to reach the hilum of the left lung. The LPAS is frequently associated with tracheobronchial tree anomalies and congenital cardiac defects. Proper assessment of the tracheobronchial and cardiovascular anomaly is essential in LPAS for planning management of the patient. Currently,

Detection of tracheal branching with computerized tomography:The relationship between the angles and age-gender

BACKGROUND The data obtained on the anatomical knowledge of the tracheobronchial system can be used for diagnosis,treatment and interventional interventions in areas such as anesthesia,thoracic surgery,pulmonary physiology.AIM To determine the tracheobronchial branching angles in pediatric and adult populations by using the multislice computed tomography(CT)and minimum intensity projection(MinIP)technique,which is a non-invasive method.METHODS Our study was carried out retrospectively.Patients who underwent contrast and non-contrast CT examination,whose anatomically and pathophysiologically good tracheobronchial system and lung parenchyma images were obtained,were included in the study.Measurements were made in the coronal plane of the lung parenchyma.In the coronal plane,right main bronchus-left main bronchus angle,right upper lobe bronchus-intermedius bronchus angle,right middle lobe bronchus-right lower lobe bronchus angle,left upper lobe bronchus-left lower lobe bronchus angle were measured.RESULTS The study population consisted of 1511 patients,753 pediatric(mean age:13.4±4.3;range:1-18 years)and 758 adults(mean age:54.3±17.3;range:19-94 years).In our study,tracheal bifurcation angle was found to be 73.3°±13.7°(59.6°-87°)in the whole population.In the pediatric group,the right-left main coronal level was found to be higher in boys compared to girls(74.6°±12.9°vs 71.2°±13.9°,P=0.001).In the adult group,the right-left main coronal level was found to be lower in males compared to females(71.9°±12.9°vs 75.8°±14.7°,P<0.001).CONCLUSIONS Our study,with the number of 1511 patients,is the first study in the literature with the largest number of patient populations including pediatric and adult demographic data,measuring the angle values of the tracheobronchial system using multislice CT and MinIP technique.Study data will not only be a guide during invasive procedures,but it can also guide studies to be done with imaging methods.

A novel wavy non-uniform ligament chiral stent with J-shaped stress-strain behavior to mimic the native trachea

Tracheal stents are an important form of treatment for benign or malignant central airway obstruction.However,the mechanical behavior of current tracheal stents is significantly different from that of the native trachea,which leads to a variety of serious complications.In this study,inspired by the structure of the native trachea,a wavy non-uniform ligament chiral tracheal stent is proposed,in which J-shaped stress-strain behavior and negative Poisson's ratio response are achieved by replacing the tangential ligament of tetrachiral and anti-tetrachiral hybrid structure with a wavy non-uniform ligament.Through the combination of theoretical analysis,finite element analysis and experimental tests,a wide range of desired J-shaped stress-strain curves are explored to mimic the native porcine trachea by tailoring the stent geometry.Besides,the negative Poisson’s ratio and auxetic diameter curves versus axial strain of the stent are also studied in detail,thus contributing to the enhancement of cross-section ventilation and reducing the migration of the stent.This novel tracheal stent with a unique microstructure shows a potential to perfectly match the physiological activities of the native trachea and thereby reduce potential complications.

A CLINICAL ANALYSIS OF 38 PATIENTS WITH PRIMARY TRACHEO BRONCHIAL TUMORS

During a 17-year period, 38 patients with primary tracheobronchial tumors received surgical treatment in PUMC Hospital. Arnong the 38. 12 had low-malignancy tracheal tumors, 11 had benign tracheal tumors, 14 had low malignancy bronchial tumors and 1 had a benign bronchial tumor. Fifteen operations were perforrned on 12 patients with low-malignancy tracheal tumors, including local resection of the tumor and tracheal wall in 4 and curettage of the tumor plus electrical cauterization in 10. Postoperative radiotherapy was used as an adjuvant treatment in 8 patients with adenocystic carcinoma. Eight patients have survived for more than 5 years and 3 patients have survived for longer than 10 years postoperatively. All 11 patients with benign tumors received curettage of the tumor and were followed up for an average of 6. 5 years. Among them, 9 are still alive. Of the 14 patients with low malignancy bronchial tumors, 5 underwent curettage of the tumor plus electrical cauterization through incision of the main bronchus or intermedial bronchus, and 7 underwent lobectomy or pneumonectomy. The authors conclude that the correct diagnosis rate can be increased by enhancing recognition of this disease and applying tracheal tomography and bronchoscopy.

What Moved into the Lung?An Unusual Case of Foreign Body Migration

FOREIGN body migration into the lung is a rare complication that can cause various symptoms. In adults, however, foreign body deposited in the luna can be tolerated and remain undetected fora long time. Delayed diagnosis and subsequent delayed treatment is usually associated with atypical complications. In this article, we describe a case of foreign body migration into the tracheobronchial tree. After a long time delay diagnosis, the foreign body was ultimately removed by operation.

Right Main Bronchus Disruption Discovered after One Year of Blunt Chest Trauma

Central airway injury is a very rare entity during blunt chest trauma. It is serious and may be fatal. Usually, it has fundamental manifestations but in some cases, it is insidious and has been discovered lately. It’s suspected when major air leaks from the chest tube and the lung fail to expand despite adequate chest drainage. Right main bronchus injuries are the most frequent. Diagnosis can be suspected clinically and confirmed by Ct scan and bronchoscopy. Conservative management can be applied in special cases but the majority of cases need surgical intervention which depends on primary reconstruction. An early diagnosis and treatment can avoid dramatic complications and provide complete recovery. Associated other organ injury is common and is an important mortality factor. Close cooperation with the emergency team and anesthesiologists is necessary. Here I presented a case of right main bronchus disruption discovered after one year of blunt chest trauma with complete lung atelectasis, managed successfully by resection of the fibrotic injured bronchus and primary reconstruction saving the lung.

Modeling micro-particle deposition in human upper respiratory tract under steady inhalation

A representative human upper respiratory tract （URT） with idealized oral region and asymmetric tracheo- bronchial （TB） airway has been modeled, and laminar-to-turbulent airflow for typical inhalation modes as well as micro-particle transport and deposition has been simulated using CFX10.0 software from Ansys Inc. on a personal computer. The asymmetric TB airway could not be replaced by an extended straight tube as outlet of the oral region while investigating the tracheal airflow field and particle deposition. Compared to an idealized oral airway with an extended straight tube, several differences could be noted： （i） The laryngeal jet extends further down the trachea and inclines towards the anterior wall; （ii） the turbulence level in trachea is less and decays more quickly; （iii） three recirculation zones are visible with intense adverse current after the glottis; （iv） deposition of small particles in trachea is reduced due to lower turbulence. Refined unstructured mesh with densified boundary layer mesh could be a proper substitute for the structured mesh in the human URT model with asymmetric TB airway. Based on the refined unstructured mesh, the physiological structure of uvula in the soft palate is properly simulated in the present human URT model.