Proximal Trachea Research Articles

An alternative method of endotracheal intubation of common marmosets (Callithrix jacchus)

Endotracheal intubation was carried out in 11 common marmosets (Callithrix jacchus). A commercially available tilting stand and a Miller laryngoscope blade were used to visualize the larynx. Anaesthesia was induced with alphaxalone (10.6 ± 1.6 mg/kg intramuscularly, followed by 3.2 ± 1.2 mg/kg intravenously). The diameter of the proximal trachea easily fitted an endotracheal tube made from readily available material (a 12 G 'over the needle' catheter). Once the tip of the endotracheal tube was at the level of the vocal folds, the tube had to be gently rotated through a 180° angle in order to pass through the larynx into the trachea. Assessment of the dimensions of the larynx and trachea, and comparison with external anatomical features of the animals (n = 10) showed that the length of the trachea could be predicted by multiplying the craniosacral length of the marmoset by a factor of 0.42.

Management of acquired tracheoesophageal fistula with various clinical presentations

Purpose To determine the best therapeutic approach for acquired tracheoesophageal fistulae in childhood by evaluation of distinct clinical presentations requiring different surgical management based on our clinical experience. Patients and Methods Seven patients with acquired tracheoesophageal fistula seen between 1999 and 2010 were retrospectively studied with regard to the presenting findings, diagnostic evaluation, therapeutic approach, and outcomes. Results Five girls and two boys with a median age of 36 months (range, 2-156 months) were treated for acquired tracheoesophageal fistula. The presenting symptoms were respiratory difficulty (n = 3), coughing (n = 2), and dysphagia with coughing (n = 2), with a median duration of 30 days (range, 1-730 days). The etiologies were disc battery ingestion (n = 3), placement of endoesophageal prosthesis for caustic esophageal stricture (n = 2), corrosive ingestion with extensive burn (n = 1), and blunt chest trauma with subsequent emergency tracheotomy (n = 1). The site of the fistulae were proximal (n = 3) and middle (n = 1) trachea, left main bronchus (n = 1), and nearly the entire posterior wall of the trachea (n = 2). The patients were variously managed: conservatively with eventual spontaneous closure (n = 1), primary repair (n = 2), and colon interposition after cervical esophagostomy (n = 4) based on the clinical evaluation on admission and the follow-up status. Stenosis of the proximal esophagus (n = 2) and esophagocolonic anastomosis (n = 2) were the only complications encountered after treatment and were successfully managed with dilatation. Conclusions The best therapeutic approach for acquired tracheoesophageal fistula can be determined with careful consideration of relevant parameters on admission, including medical history, presenting findings, etiology, and characteristics of the fistula, in addition to the clinical evaluation in the follow-up period. In general, conservative management should precede definitive surgical intervention both to allow for possible spontaneous closure and also to achieve optimal preoperative status. Primary repair or a staged surgical approach can be best selected by giving priority to the patient's airway security.

Invited Commentary

Idiopathic tracheal stenosis (ITS) is a rare disease characterized by inflammation and stenosis of the proximal airway. Inflammation is most severe at the level of the cricoid cartilage, although the proximal trachea or subglottis may be involved. Interestingly, the disease is almost always confined to young women.

Endoscopic tracheoplasty for treating tracheotomy-related airway stenosis

Posttracheotomy “lambdoid” deformity of the trachea is a specific variant of adult laryngotracheal stenosis in which airway obstruction is caused by inward collapse of over-resected tracheal cartilage because of post-decannulation stomal contracture. The lesion extends over 1 or 2 tracheal rings with a normal proximal and distal trachea. The trachealis is not involved and there is usually a small anterior bridge of preserved trachea. Conventional treatment involves resection of the damaged trachea and end-to-end anastamosis. The development of “shared-airway” anesthesia techniques and the advancements in endoscopic surgery have made it possible to resect these lesions with minimal morbidity and a shorter hospital stay.

The effects of extubation with an inflated versus deflated endotracheal tube cuff on endotracheal fluid volume in the dog

ObjectiveThe purpose of this study was to investigate the effect of extubation with the endotracheal tube (ETT) cuff inflated versus deflated on endotracheal fluid volume in normal canine cadavers. Study DesignProspective randomized blinded controlled cadaver study. AnimalsSixteen adult Beagle cadavers weighing 10.7 ± 1.7 kg (mean ± SD) and <2 years of age. MethodsCadavers were orotracheally intubated in lateral recumbency, and the ETT cuffs were inflated to a closing pressure of 20 cm H2O before barium was introduced orad to the cuff. The dogs were randomly assigned to an ETT cuff extubation condition of deflated or unchanged from the original closing pressure. After extubation, lateral thoracic radiographs of the cadavers were obtained and scored by three independent blinded reviewers. Each reviewer ordered all 16 lateral radiographs from most to least intratracheal contrast and also estimated residual intratracheal contrast volume. ResultsDogs extubated with a deflated ETT cuff had a median rank of 13 and dogs extubated with an inflated ETT cuff had a median rank of 4.5 (p < 0.0001). Dogs extubated with a deflated ETT cuff had an estimated intratracheal volume of fluid of 1.8 mL ± 0.7 mL (mean ± SD) and dogs extubated with an inflated ETT cuff had an estimated volume of 0.9 mL ± 0.5 mL (p < 0.0001). Fleiss Kappa for agreement among evaluators was 0.875. Conclusions and clinical relevanceExtubation with the cuff inflated removed more liquid contents from the trachea than extubation with the cuff deflated and may assist in the prevention of pulmonary aspiration when fluid is present in the proximal trachea. The technique did not remove all fluid so the potential for pulmonary damage remains.

Tracheal laceration during intubation of a double-lumen tube and intraoperative fiberoptic bronchoscopic evaluation through an LMA in the lateral position -A case report-

A 76-year-old, 148-cm woman was scheduled for right upper lobectomy. A 32 Fr left-sided double lumen tube was placed using a conventional technique. Despite several attempts under fiberoptic bronchoscope-guidance, we could not locate the double lumen tube properly. We thus decided to proceed with the bronchial tube in the right mainstem bronchus. During surgery, 8-cm-long laceration was noted on the posterolateral side of the trachea. To check the possibility of laceration of the proximal trachea, the double lumen tube was changed to an LMA for use as a conduit for fiberoptic bronchoscopic evaluation in the lateral position. A plain endotracheal tube with the cuff modified and collapsed was re-intubated after evaluation. And then she was transferred to SICU.

Microvascular blood flow in the airway mucosa modulates bronchoconstriction

in this issue of the Journal of Applied Physiology , Mazzone et al. ([4][1]) demonstrate the role of α-adrenergic control of airway vasculature tone, which in turn regulates the magnitude of airway smooth muscle response to bronchoconstrictive challenges. They demonstrate by intravital microscopy

Surgical Management of Acquired Nonmalignant Tracheoesophageal and Bronchoesophageal Fistulae

Acquired nonmalignant fistulae between the airway and esophagus (tracheoesophageal fistulae [TEF]) are rare life-threatening conditions. Several management approaches have been proposed, while the optimal strategy remains controversial. This study is a retrospective review of all patients with TEF treated at our institution from 1978 through 2007. Thirty-five patients (22 men, 13 women) underwent surgical repair of acquired nonmalignant TEF. Median age was 55 years (range, 5 to 78). Most common causes were the following: complications of esophageal surgery (11), trauma (6), granulomatous infection (5), stent erosion (4), and prolonged mechanical ventilation (2). Location was proximal trachea in 7, mid-trachea in 5, and distal trachea or bronchus in 23. Fifty-six operations were performed. Six patients had staged repair, with 1 patient requiring 4 operations for recurrent TEF. TEF division and primary repair was performed in 18 patients, esophageal resection with reconstruction in 4, and esophageal diversion in 6. Four patients had suture closure of the esophageal or tracheal defect only, and 3 required segmental tracheal or bronchial resection. Four patients were ventilator dependent at the time of repair. Pedicled tissue flaps were used in 28 patients (80%). Operative mortality was 5.7% (2 of 35). Nineteen patients (54.3%) had complications. Median hospital stay was 14 days (range, 4 to 209). Median follow-up was 30.4 months (range, 0.5 to 233) and complete in 34 (97.1%). Three patients (8.6%) developed recurrent TEF. Twenty-nine patients resumed oral intake. One patient required a permanent tracheal T tube. Single-stage primary repair of both airway and esophageal defects with tissue flap interposition can safely be performed successfully in the majority of patients with acquired nonmalignant TEF.

The usefulness of laryngotracheal separation in the treatment of severe motor and intellectual disabilities

Intractable aspiration is a life-threatening medical problem in patients with severe motor and intellectual disabilities (SMID). Laryngotracheal separation (LTS) is a surgical procedure for the treatment of intractable aspiration which separates the upper respiratory tract from the digestive tract. We performed LTS for 14 patients with SMID to prevent intractable aspiration, performing two types of operation. The standard diversion procedure connected the upper trachea to the esophagus. The modified diversion includes closure of the proximal trachea and a high tracheostomy, avoiding a tracheoesophageal anastomosis. LTS was performed on 14 patients. Operations performed before the LTS included tracheostomy in four patients, fundoplication in six and gastrostomy in two. A standard diversion was performed in 11 patients and a modified diversion in 3. There were no operative complications. Eleven patients were safely transferred to home-care after their LTS. Twelve patients are still alive and two died some months after operation. One patient died from their primary disease and the other died a tracheo-innominate artery fistula (TIAF). We recently experienced a patient who was at high risk of developing a TIAF. LTS is an effective operation, preventing intractable aspiration in patients with severe motor and intellectual disabilities. The results are similar for the standard or modified diversion procedure with the procedure chosen being related to the initial tracheostomy site. The most serious complication is a lethal TIAF.

Tracheal Non-Hodgkin's Lymphoma Masquerading as Benign Granulation Tissue: A Report of Two Cases

Primary tracheal non-Hodgkin's lymphoma (NHL) is rare, with fewer than 30 cases reported to date. We review the clinical presentation, evaluation, and treatment of 2 cases of tracheal NHL mimicking granulation tissue. The first patient was a 67-year-old man with myelodysplastic syndrome and Crohn's disease who had a recurring lesion of the proximal trachea causing significant airway obstruction. The second patient was a 47-year-old man with a history of multiple intubations who presented with dyspnea and stridor due to circumferential tracheal stenosis. In both cases, bronchoscopy revealed abundant granulation tissue, and the initial biopsy results indicated benign disease. However, after requests from the diagnostic team to rule out lymphoma, additional immunohistochemical stains and polymerase chain reaction testing confirmed NHL. Radiotherapy was initiated. The first patient responded well and remains disease-free after 4 years. The second patient died of airway obstruction due to severe distal tracheal stenosis. Recurrent granulation tissue should raise the suspicion of malignancy and prompt further tissue evaluation for evidence of lymphoma. Steroids for airway compromise may cause progression to mature stenosis as prednisone is used in the treatment of lymphoma. Localized disease involving the central airways may be treated successfully with limited chemotherapy and radiotherapy.

Tissue engineering and the use of stem/progenitor cells for airway epithelium repair

Stem/progenitor cells can be used to repair defects in the airway wall, resulting from e.g., tumors, trauma, tissue reactions following long-time intubations, or diseases that are associated with epithelial damage. Several potential sources of cells for airway epithelium have been identified. These can be divided into two groups. The first group consists of endogenous progenitor cells present in the respiratory tract. This group can be subdivided according to location into (a) a ductal cell type in the submucosal glands of the proximal trachea, (b) basal cells in the intercartilaginous zones of the lower trachea and bronchi, (c) variant Clara cells (Clara v-cells) in the bronchioles and (d) at the junctions between the bronchioles and the alveolar ducts, and (e) alveolar type II cells. This classification of progenitor cell niches is, however, controversial. The second group consists of exogenous stem cells derived from other tissues in the body. This second group can be subdivided into: (a) embryonic stem (ES) cells, induced pluripotent stem (iPS) cells, or amniotic fluid stem cells, (b) side-population cells from bone marrow or epithelial stem cells present in bone marrow or circulation and (c) fat-derived mesenchymal cells. Airway epithelial cells can be co-cultured in a system that includes a basal lamina equivalent, extracellular factors from mesenchymal fibroblasts, and in an air-liquid interface system. Recently, spheroid-based culture systems have been developed. Several clinical applications have been suggested: cystic fibrosis, acute respiratory distress syndrome, chronic obstructive lung disease, pulmonary fibrosis, pulmonary edema, and pulmonary hypertension. Clinical applications so far are few, but include subglottic stenosis, tracheomalacia, bronchiomalacia, and emphysema.

Indications and Results of Anterior Mediastinal Tracheostomy for Malignancies

This study was designed to assess the early and long-term results, and determine suitable indications of anterior mediastinal tracheostomy, after radical resection for cervicothoracic malignancies. From 1985 to 2009, 13 patients ranging in age from 40 to 75 years underwent an anterior mediastinal tracheostomy for malignancy, 2 as an isolated procedure, 5 with concomitant laryngectomy, and 6 with concomitant laryngopharyngoesophagectomy. The patients had subglottic carcinoma, proximal tracheal carcinoma invading the subglottic larynx (n = 6), stomal recurrence following laryngectomy (n = 4), esophageal carcinoma invading the proximal trachea (n = 2), or tracheal recurrence after conventional resection (n = 1). The postoperative course and outcome were assessed in all patients. In 5 patients, the postoperative course was uneventful. There were 2 in-hospital deaths, and 6 patients experienced nonfatal complications including three pharyngocutaneous fistulas, two pharyngogastric or pharyngocolic anastomotic leaks, and one pulmonary embolism. Satisfactory airway was achieved in 7 patients presenting with proximal obstruction, and ability to tolerate oral feeding, in 2 patients with esophageal carcinoma. The mean follow-up time for survivors was 89 months (range, 9 to 201 months). Patients with esophageal carcinoma or recurrence of tracheal carcinoma showed a poor outcome. In contrast, in the subgroup of patients with head and neck malignancy, 3-year and 5-year survival rates were 57% and 43%, respectively. Our results and survival analysis from the literature suggest that suitable indications for anterior mediastinal tracheostomy are (1) carcinoma of the subglottic region or proximal trachea invading the subglottic larynx, (2) stomal recurrence after laryngectomy, and (3) well-differentiated thyroid carcinoma invading the trachea or recurrence.

Dynamic Airway Evaluation with Volume CT: Initial Experience

Purpose The purpose of the study was to prospectively establish the use of a novel multidetector computed tomography unit (MDCT) with 320 × 0.5 detector rows for the evaluation of tracheomalacia by using a dynamic expiratory low-dose technique. Methods Six adult patients (5 men, 1 woman; mean age, 53.7 years [37–70 years]) referred for a clinical suspicion of tracheomalacia were studied on a 320-row MDCT unit by using the following parameters: 120 kVp, 40–50 mA, 0.5-second gantry rotation, and z-axis coverage of 160 mm sufficient to cover the thoracic trachea to the proximal bronchi. Image acquisition occurred during a forceful exhalation. The image data set was subject to the following analyses: cross-sectional area of airway lumen at 4 predefined locations (thoracic inlet, aortic arch, carina, and bronchus intermedius) and measurement of airway volume. Results All 6 patients had evidence of tracheomalacia, the proximal trachea collapsed at a later phase of expiration (3–4 seconds) than the distal trachea (2–3 seconds). The most common region of airway collapse occurred at the level of the aortic arch (5/6 [83%]), Three patients (50%) had diffuse segmental luminal narrowing that involved the tracheobronchial tree. The radiation dose (estimated dose length product, computed tomography console) measured 293.9 mGy in 1 subject and 483.5 mGy in 5 patients. Conclusions Four-dimensional true isophasic and isovolumetric imaging of the central airways by using 320-row MDCT is a viable technique for the diagnosis of tracheomalacia; it provides a comprehensive assessment of airways dynamic.

A Case of Tracheal Capillary Hemangioma in an Adult

Capillary hemangioma of the trachea is an extremely rare benign tumor in adults. We present the case of a 28-year-old woman with hemoptysis owing to a tumor of the proximal trachea. The tumor was removed by rigid bronchoscopy. The resulting specimens showed capillary hemangioma without any signs of malignant transformation. This presentation is the first case in Korea. Although tracheal capillary hemangioma is a rare disease, we should consider it as a possible cause of hemoptysis in the young adult.

Treatment of Idiopathic Laryngotracheal Stenosis

Idiopathic laryngotracheal stenosis is a very rare condition characterized by an inflammatory cicatricial stenosis at the level of the cricoid cartilage and proximal trachea. Treatment options range from conservative short-term solutions to definitive surgical resection and reconstruction.

Ozone uptake during inspiratory flow in a model of the larynx, trachea and primary bronchial bifurcation

Three-dimensional simulations of the transport and uptake of a reactive gas such as O(3) were compared between an idealized model of the larynx, trachea, and first bifurcation and a second "control" model in which the larynx was replaced by an equivalent, cylindrical, tube segment. The Navier-Stokes equations, Spalart-Allmaras turbulence equation, and convection-diffusion equation were implemented at conditions reflecting inhalation into an adult human lung. Simulation results were used to analyze axial velocity, turbulent viscosity, local fractional uptake, and regional uptake. Axial velocity data revealed a strong laryngeal jet with a reattachment point in the proximal trachea. Turbulent viscosity data indicated that jet turbulence occurred only at high Reynolds numbers and was attenuated by the first bifurcation. Local fractional uptake data affirmed hotspots previously reported at the first carina, and suggested additional hotspots at the glottal constriction and jet reattachment point in the proximal trachea. These laryngeal effects strongly depended on inlet Reynolds number, with maximal effects (approaching 15%) occurring at maximal inlet flow rates. While the increase in the regional uptake caused by the larynx subsided by the end of the model, the effect of the larynx on cumulative uptake persisted further downstream. These results suggest that with prolonged exposure to a reactive gas, entire regions of the larynx and proximal trachea could show signs of tissue injury.

Visual Vignette

Case Presentation: A 40-year-old woman with a history of asthma presented with a 2-week history of progressively worsening “heavy” breathing accompanied by an intermittent cough that was productive of blood-tinged sputum. Her physical examination showed wheezing but no stridor. Spirometry testing revealed a forced expiratory volume in 1 second of 1.33 L and a vital capacity of 3.08 L, in comparison with 2.5 L and 3.5 L, respectively, a year previously. The flow volume loop study was significant for flattened inspiratory and expiratory limb curves. Plain radiography of the neck demonstrated a subglottic tracheal mass (Fig. 1, arrow), and reconstructional computed tomographic imaging disclosed a nearly compromised airway (Fig. 2, blue area, arrow). Laryngoscopy revealed a smooth lobulated mass (1.0 by 1.5 cm) that originated from the proximal trachea anteriorly, with an approximated 90% endotracheal narrowing. An emergent resection of a hypervascular tumor was performed, and the patient recovered uneventfully. Immunohistochemical analysis showed that the tumor was strongly positive for neuron-specific enolase, chromogranin (Fig. 3 A), and synaptophysin (Fig. 3 B) and negative for cytokeratin AE1/3 (Fig. 3 C), CAM 5.2, and calcitonin. Sustentacular cells expressed S-100 protein (Fig. 3 D). What is the diagnosis?

Abnormal development of tracheal innervation in rats with experimental diaphragmatic hernia

We previously demonstrated that tracheobronchial innervation, originated from the vagus nerve and hence of neural crest origin, is deficient in rats with experimental congenital diaphragmatic hernia (CDH). The present study examines the development of this innervation during fetal life in an attempt to understand the nature of these deficiencies. Pregnant rats were given either 100 mg nitrofen or vehicle on E 9.5. Embryos were recovered on E15 and E18. Control and nitrofen/CDH pups (n = 10 each) were studied on each of these days and compared with our previous results on E21. Whole mount preparations of tracheas stained for anti-protein gene product 9.5 (PGP 9.5) and smooth muscle contractile alpha-actin were examined under confocal microscopy for the morphology of intrinsic neural network. Sections of tracheas were immunostained with anti-low-affinity neurotrophin receptor (p75(NTR)), neural cell marker PGP 9.5, and anti-glial cell marker S100 antibodies. The proportions of sectional areas occupied by neural and glial structures were measured in the proximal and distal trachea. PGP 9.5 protein, and mRNA expressions were determined. Mann-Whitney tests with a threshold of significance of P < 0.05 were used for comparison. Positive staining for p75(NTR) confirmed the neural crest origin of tracheal neural cells. The neural network appeared less organized on E15, and it was less dense on E18 in nitrofen-exposed embryos than in controls. The proportions of section surface occupied by neural elements were similar in both groups on E15, but that of glial tissue was significantly increased in nitrofen-exposed embryos. On E18, the relative neural surface was significantly reduced in CDH embryos in contrast with increased glial tissue surface. On E21 the proportion of neural tissue was reduced only in the distal trachea. The expression of PGP 9.5 protein was decreased in CDH fetuses on E18 and E21. In contrast, PGP 9.5 mRNA levels were increased in CDH fetuses on E18 and E21. The development of intrinsic innervation of the trachea in rats with CDH is abnormal with reduction of neural tissue accompanied by increase of glial tissue that could represent a response to neural damage. The significance of increased PGP 9.5 mRNA levels is unclear.

Congenital tracheal malformation in cystic fibrosis transmembrane conductance regulator‐deficient mice

In cystic fibrosis (CF) patients, the major alteration in pulmonary function is due to peripheral airway obstruction. In the present study, we investigated the possibility that alterations in the extrathoracic airways, particularly in the trachea that expresses high levels of CFTR (CF transmembrane conductance regulator), may contribute to respiratory dysfunction. We performed morphological analyses of the trachea and airway functional studies in adult Cftr knockout (Cftr(-/-)) and F508del-CFTR mice and their controls. Macroscopic and histological examination of the trachea showed the presence of one to seven disrupted or incomplete cartilage rings in Cftr(-/-) mice (23/25) while only a few Cftr(+/+) mice (6/25) had one abnormal ring. Tracheal defects were mainly localized in the proximal trachea. In 14 Cftr(-/-) mice, frontal disruption of the first three to six rings below the cricoid cartilage were associated with upper tracheal constriction. Similar tracheal abnormalities were detected in adult F508del-CFTR and in newborn Cftr(-/-) and F508del-CFTR mice. Tracheal and ventilatory function analyses showed in Cftr(-/-) mice a decreased contractile response of the proximal trachea and a reduced breathing rate due to an increase in the inspiratory and expiratory times. In F508del-CFTR mice, the expiratory time was longer than in controls. Therefore, these structural and functional abnormalities detected in adult and newborn CF mouse models may represent congenital malformations related to CFTR dysfunction. These results raise important questions concerning the mechanisms governing tracheal development within the context of CFTR protein dysfunction and the implication of such abnormalities in the pathogenesis of airway disease in CF.

Second primary small cell carcinoma of the trachea in a breast cancer survivor: a case report and literature review

Small cell carcinoma of the trachea is a rare entity and only a few cases have been described, none as a second malignant neoplasm. This is the first report of a metachronous second primary of the trachea with small cell histology in a breast cancer survivor. A 25-year-old woman was diagnosed initially with an infiltrating ductal carcinoma of the breast, and was treated with modified radical mastectomy followed by adjuvant chemo-radiotherapy. 10 years later, she presented with breathlessness and central airway obstruction. Bronchoscopy revealed an intraluminal lesion in the proximal trachea, which was reported as small cell carcinoma on biopsy. There was no evidence of loco-regional recurrence of the previously treated breast cancer. Whole-body positron emission tomography did not show any distant metastases. As it was a small cell carcinoma, she was treated with concurrent chemo-radiotherapy and remains loco-regionally controlled. Decision-making in such instances should take into account prior treatment and needs to be individualized. There is a need for increased awareness amongst primary care physicians regarding second malignant neoplasms in the long-term follow-up of breast cancer patients treated with radiation and chemotherapeutic agents that have carcinogenic potential.