Tracheal stenosis

This curve is seen where a large airway has a fixed orifice through which gas is able to flow, such as may be seen in patients with tracheal stenosis. The peak inspiratory and expiratory flow rates are, therefore, dependent on the diameter of the orifice rather than effort. The curves should be drawn almost symmetrical as above, with both limbs demonstrating markedly reduced flow. The TLC and RV are generally unaffected. 

Steroidal alkaloids found in the Filiaceae family, primarily Veratrum and Zygadenus, have been responsible for large losses in livestock. Fluman and livestock deaths have occurred from accidental ingestion of death camas (Panter et al., 1987). Thousands of lambs have died or been destroyed because of Veratrum-indvLCQd malformations, most notably a craniofacial defect called cyclopia (Binns et al., 1965 James, 1999 Figure 2.8). Tracheal stenosis, skeletal malformations and early embryonic death are also common (Keeler and... 

An important late sequela of mustard inhalation is a tracheal/bronchial stenosis that necessitates bronchoscopy and other procedures (Freitag et al., 1991). Mustard has been reported to create a long-term sensitivity to smoke, dust, and similar arrbome particles, probably as a result of clinically unapparent bronchospasm (Morgenstern et al., 1947 Buscher and Conway, 1994). 

Fig. 13.6.3D cross-sectional profile of a patient with tracheal stenosis. The cross-sectional profile (thin black line) shows the actual area in mm at a dedicated distance from the vocal cords, as measured in mm. There is one relevant stenosis (position 1), whereas 2 subsequent stenoses (position 2 and 3) are irrelevant. Quantitative analysis of the degree and length of the stenoses are provided at the lower left margin of the graph. Modified from Sorantin E et al. 3D cross section of the laryngotracheal tract. A new method for visualization and quantification of tracheal stenoses. Radiologe 2003 43 1056-1068... 

Hoppe H, Thoeny HC, Dinkel HP, Zbaren P, Vock P (2002) Virtual laryngoscopy and multiplanar reformats with multirow detector CT for detection and grading of upper airway stenosis. Rofo 174 1003-1008 Jolesz FA, Lorensen WE, Shinmoto H et al (1997) Interactive virtual endoscopy. AJR Am J Roentgenol 169 1229-1235 Joshi AR, Khanna PC, Merchant SA, Khandelwal A, Agrawal N, Karnik ND (2003) Role of multidetector CT virtual bronchoscopy in the evaluation of post-tracheostomy tracheal stenosis - a preliminary study. J Assoc Physicians India 51 871-876... 

Rodel R, Rodenwaldt J, Hommerich CP (2000) Inner surface imaging of laryngeal and tracheal stenosis by spiral-CT role of a new diagnostic procedure. Laryngorhinootolo-gie 79 584-590... 

The most important morphological examination prior to insertion of an airway stent is a spiral computed tomography (CT) of the major airways. A CT enables a delineation of the airway obstruction. It further demonstrates the length of stenosis, grade of obstruction, and allows calibrated measurements of the smallest diameter of the obstruction. CT can also differentiate a mucosal obstruction from a submucosal cause of obstruction, and further extra-tracheal or exo-bronchial disease responsible for airway comprise. Another advantage of CT is the possibility to assess the relation of the underlying cause of obstruction to other crucial mediastinal and/or pulmonary structures (e.g., major vessels, esophagus, heart, lymph nodes). 

The first report on the oldest metal stent used in the tracheobronchial system was pubUshed by Wallace et al. in 1986 (Wallace et al. 1986). Since then, several studies on the use of this stent type have been pub-hshed and the stent became one of the most frequently applied metal stents in tracheobronchial mahgnancy. Wallace and colleagues initially reported on two cancer patients. Gianturco stents were placed in one to dilate a postoperative bronchial stenosis that caused pneumonia, and in the second to support a tracheal graft that collapsed with respiration. Stents were successfully placed and the patients symptoms improved (Wallace et al. 1986). 

George and colleagues (1992) treated nine patients with malignant central airway obstruction due to tracheal (n=3) or main bronchial ( =6) stenosis with Gianturco stents. All patients suffered from severe dyspnea or asphyxia (four were emergency treatments). All patients had dramatic and rapid reUef of their symptoms after stent insertion. Two patients with intraluminal tumor growth required additional endobronchial measures to control local tumor progression. Patients survived between 3 weeks and 8 months after the intervention. Causes of death were cachexia or pneumonia. 

Bolliger CT, Heitz M, Hauser R, Probst R, Perruchoud AP (1996) An airway Wallstent for the treatment of tracheobronchial malignancies. Thorax 51 1127-1129 Bolliger CT, Wyser C, Wu X et al. (1999) Evaluation of a new self-expandable silicone stent in an experimental tracheal stenosis. Chest 115 496-501... 

Nomori H, Horio H, Imazu Y, Suemasu K (2000) Double stenting for esophageal and tracheobronchial stenoses. Ann Thorac Surg 70 1803 1807 Noppen M, Dhase J, Meysman M et al. (1996) A new screw-thread tracheal endoprosthesis. J Bronchol 3 22-26 Noppen M, Meysman M, Claes I et al. (1999) Screw-thread vs Dumon endoprosthesis in the management of tracheal stenosis. Chest 115 532-535... 

Trachea TE has been one of the most promising approaches to providing a potential clinical application for the treatment of long-segment tracheal stenosis. The sources of the cells are particularly important as the primary factor for TE. Besides autologous mature cells, various stem cells, including bone marrow-derived mesenchymal stem cells (MSCs), adipose tissue—derived stem cells, umbilical cord blood—derived mesenchymal stem cells, amniotic fluid stem cells, embryonic stem cells, and induced pluripotent stem cells, have received extensive attention in trachea TE [118]. 

However, the trachea is also made of cartilage and can be involved with repetitive cycles of inflammation, ulceration, and scarring that may ultimately present with tracheal stenosis. The two CTDs most often associated with tracheal stenosis include relapsing polychondritis and necrotizing granulomatous vasculitis. Stenosis in both diseases is most common in the subglottic space. 

Imbalance between work of breathing and respiratory muscle capacity Critical illness polyneuropathy or myopathy Upper airway obstraction (e.g., tracheal stenosis)... 

Most children are managed with NPPV (1,50). However, some require invasive ventilation through a tracheostomy. The main indications for a tracheostomy in children are airway abnormalities such as tracheobronchomalacia or tracheal stenosis, chronic disease of prematurity, and NMD (1,51,52). The indications for a tracheostomy are comparable to those of the adult population. They include the persistence of hypercapnia despite NPPV and additional measures such as daytime mouthpiece ventilation, aspiration, and bulbar dysfunction (53). In children, NPPV is more difficult to perform in those who might be 24-hour dependent, than in adults. Infants with primaiy alveolar hypoventilation (Ondine s curse) are preferentially ventilated by means of a tracheostomy (18). Tracheostomy ventilation favors airway inflammation (54) and may affect speech and language development (55). In children with progressive NMD, the decision of a tracheostomy has to be discussed on an individual basis, taking into account the familial environment and the parent s and child s perspective (52,56). In any case, sending children home with invasive ventilation is more difficult than when noninvasive ventilation is used (52). 

Respiratory tract 1. Bronchiolitis obliterans 2. Bronchial stenosis 3. Neovascularization and tracheal vulnerability 4. Chronic cough with blood sputum 5. Diminished mucociliary clearance 6. Interstitial lung disease 7. Emphysema... 

The most common airway problems are anastomotic dehiscence and bronchial stenosis due to strictures. The reason is mostly a lack of perfusion of the bronchial tree, as the donor airways depend on a retrograde pulmonary-to-bronchial arterial circulation until revascularization of the bronchus wall occurs. Ischaemia is greater on the right main bronchus than on the left, therefore anastomotic healing is better on the left and early stenotic problems or dehiscence occur on the right anastomosis more frequently than on the left side. In the early years of transplantation the en bloc technique was mainly performed with a high incidence of tracheal dehiscence, which prompted the development of bilateral lung transplantation. 

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