What Is a Tracheal Stent?

When a person breathes, air enters and exits the lungs through the bronchi. The bronchus is like a tree branch. It is divided into a large bronchus and a small bronchus. At the end of the smallest bronchi, there is an air sac, where oxygen is absorbed by the human body to support it, and carbon dioxide is discharged from the body.

1. Tracheal stent 1. Introduction:

Trachea and bronchoconstriction caused by inflammatory granulomas, scars, tuberculosis, trauma, tracheomalacia, amyloidosis, tumors and other diseases can cause obstructive pneumonia, atelectasis and dyspnea. Severe cough and other symptoms can cause respiratory failure and endanger life. Tracheal stent placement is one of the important methods to treat airway stenosis, which can quickly relieve dyspnea and improve clinical symptoms. The application of airway stents can be traced back to the 1890s. In the past 20 years, with the continuous development of materials science and the popularization of bendable bronchoscopes in clinics, airway stent placement has been widely used in clinical practice, providing opportunities for further treatment and improving the quality of life of patients.

With the successful application of metal stents in angioplasty, in recent years it has also begun to be used clinically for tracheal stenosis, and satisfactory results have been achieved. The stent used is a stainless steel stent and a nickel-titanium memory alloy mesh stent. The stent is braided from the above nickel-titanium memory alloy wire for the main trachea and bronchus. In order to prevent tumors from growing into the cavity, esophageal-tracheal fistulas are blocked, and some stents are partially or fully covered.

Figure 1. Diagram of tracheal stent placement

2. Tracheal stent 2. What are the types of tracheal stent

An ideal tracheal stent should have the following characteristics: easy to insert and remove; has good expansion ability without causing damage to the tracheal mucosa; there are various models of different sizes for various tracheal stenosis; can maintain the placement Position does not move; Does not stimulate tracheal mucosa to aggravate infection and promote granulation tissue formation; Does not block tracheal drainage; Does not inhibit ciliary movement and clearance of secretions.

Y Tracheal stent "Y" tracheal stent

The Y-shaped stent completely conforms to the anatomical structure of the tracheal bulge; the original main body and two branches design, the stent and the tracheal bulge fit completely, will not be displaced and deformed, which is conducive to the discharge of breath and sputum; It can reduce the stimulation and block the fistula, and keep the airway open for a long time. The Y-shaped design can complete the treatment of multiple lesions in the carina at one time, reducing the incidence of surgical complications, reducing the difficulty and cost of the operation.

Figure 2. "Y" Tracheal Stent

Tracheal stent

The main body of the stent is connected to the branch, and the branch is fixed to reduce displacement and reduce complications. The main body of the stent has no membrane, which is firmly fixed and easy to recover. The blind end of the bullet is double-layered to effectively block the fistula and stimulate the small stent. The outer wall is provided with positioning marks for easy operation.

Figure 3. Bronchial stump blocking fistula stent

Tracheal stent main trachea, bronchial stent

The main trachea and bronchial stent are cylindrical, and the unique weaving method allows the stent to have a good support and shaping effect on the trachea lumen; the full-membrane design helps the fistula to heal, while keeping the airway open for a long time; , Bronchus and other specifications.

Figure 4. Main trachea and bronchial stent

3. Tracheal stent 3. Insertion of tracheal stent

At present, there are three methods of stent placement in China: one is guided by fiberoptic bronchoscope, and the stent is placed under X-ray perspective positioning; the other is placed under rigid bronchoscopy under general anesthesia; the third is straight Place the stand underneath.

According to the anatomical characteristics and lesions of different parts of trachea and bronchus, choose the appropriate type of stent. Take the main bronchial stent as an example: after the guide wire is inserted, the dilator and the long sheath with an impermeable X-ray mark at the front end are introduced along the guide wire (as shown in FIG. 5A); Withdraw the dilator and leave the position of the long sheath unchanged (as shown in Figure 5B); place the stent into the long sheath and quickly push it to the narrow part (as shown in Figure 5C); fix the pusher and quickly retract it Sheath, release the stent (as shown in Figure 5D).

Figure 5. Tracheal stent placement steps

4. Tracheal stents 4. Indications and contraindications of tracheal stents:

(1) Indications: The placement of tracheal stent mainly achieves the following purposes: Reconstruction of the lumen of the organic narrow airway in the central airway. Support of weak cartilage in trachea and bronchial softening. Blocking of trachea, bronchial fistula or fissure. The indications for tracheal stent implantation are gradually expanding, but they are still mainly used as palliative treatment. Stent placement for tracheal stenosis caused by malignant tumors is well established. Since the stent may be corroded and collapsed in the airway for a long time, and may cause granulation tissue hyperplasia and airway damage, the role of long-term stent placement in tracheal stenosis caused by benign diseases remains to be further evaluated.

(2) Contraindications: As there are few treatment options, tracheal stent placement for benign tracheal stenosis is currently considered clinically reasonable. Generally speaking, all benign and malignant trachea and main bronchus stenosis who have lost the opportunity for surgery or are unwilling to undergo surgery can be treated with stents. However, the following situations must be treated with caution: Children, because the length and width of children's trachea are constantly changing. Developmental changes, that is, growth and widening, and the inner diameter and length of the stent are shaped once selected, and will not adapt to the growth of the trachea. tracheal bleeding. Atmospheric stenosis with multiple small airway stenosis and obstruction, severe pneumothorax and mediastinal subcutaneous emphysema. severely impaired cardiopulmonary function. Glottic involvement of the tumor caused glottic and subglottic stenosis, and the stent specifications did not match the lesion. Patients with severe infection of trachea and bronchus.

Tracheal stent extension reading:

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[2] He Yibing, Wu Hongcheng, Yu Biyun. Fiber bronchoscope-guided lower airway Y-type stent implantation for the treatment of 13 cases of complex airway stenosis [J]. Zhejiang Journal of Integrated Traditional Chinese and Western Medicine, 2012, 22 (1): 35 -37

[3] Li Hong, Yan Dandan, Peng Hua, et al. Nursing of recoverable full-coverage tracheal stent implantation [J]. China Medical Herald, 2012, 14 (6): 1078-1079

[4] Zeng Weijie, Zhi Xiaoxing, Meng Meng, et al. Biomechanical characteristics and biocompatibility of tracheal stent after implantation. China Tissue Engineering Research and Clinical Rehabilitation, 2009, 13 (13): 2573-2576

[5] Guo Xinglai, Wang Song, Lu Chengcheng, et al. Efficacy analysis of tracheal stent in the treatment of malignant tracheal stenosis. Anhui Medical Journal, 2012, 33 (5): 565-567

[6] Wei Ning, Xu Hao, Zu Maoheng, et al. Complications of tracheal stenting for tracheal malignant stenosis. Chinese Journal of Interventional Imaging and Therapy, 2012, 9 (3): 167-171

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[8] Zhang Rufeng, Chen Liping. Application of artificial trachea and tracheal stent materials. China Tissue Engineering Research and Clinical Rehabilitation, 2011, 51 (15): 9651-9654