Bronchoscopic stenting Bendable bronchoscopic stenting is a method of maintaining airway ventilation using an artificial device that maintains the integrity of the lumen – a stent – and applying a stent inserter to the airway under X-ray or direct bronchoscopic view. Currently, there are many types of airway stents, the most common of which are expandable metal stents, silicone stents and hybrid stents, etc. With the advancement of technology, more types of stents will appear. At present, expandable metal stents are the most commonly used. Indications】 1.Lumen reconstruction of organic central airway stenosis: including malignant tumors and benign lesions. Malignant airway stenosis is the first choice for endotracheal stent placement, while for benign airway stenosis, stent placement should be cautious. 2.Stenting of weak cartilage in tracheal and bronchial cartilage: such as polychondritis, tracheobronchial cartilage, tuberculosis infection after bronchial cartilage softening resulting in limited softening, etc. 3, trachea, bronchial fistula or fissure closure: such as tracheoesophageal fistula, bronchial stump fistula or fissure and bronchial anastomosis fistula or fissure, etc. 4, other: such as posterior scoliosis compression of the airway, fibrous mediastinitis resulting in airway narrowing, etc. Method】 Bendable bronchial interventional stent placement is usually done under X-ray fluoroscopy or direct bronchoscopy, however, it is also possible to use bronchoscopy only to mediate the placement. The choice is mainly based on the facilities and conditions of the hospital, the custom and proficiency of the surgeon, etc. This method is mainly for the placement of expandable metal stents. 1. Preparation before insertion (1) Understand the general condition of the patient and clarify the extent and degree of the stenosis and the nature of the underlying lesion. In particular, the proximal and distal airway diameters of the stenotic airway should be determined exactly. (2) Stent selection: The length of stents should all be 10-15 mm beyond the stenosis site. To ensure good stent fixation, for self-expanding stents, it is best to select a stent with a diameter 2 mm larger than the expected diameter after stent placement. (3) Anesthesia: The purpose of anesthesia is to relieve pain and reduce surgical risk. For stent placement in the trachea, it is best to use general anesthesia, while for stent placement in the main bronchus and its lobes and segmental bronchus, it can be done under local anesthesia. 2. Specific stent placement methods (1) Stent introduction: Generally, the lesion site is first measured with a bronchoscope to understand the specific length of the specific release stent and marked in the inserter. The guide wire is then fed through the bronchoscopic working orifice to the lesion site, the bronchoscope is withdrawn, the guide wire is left in the airway, and the stent inserter with the stent is fed into the lesion site along the guide wire. (2) Positioning and release of the stent: positioning under X-ray or positioning under direct bronchoscopy. The former is to turn on the X-ray fluoroscope during the bronchoscopic measurement of the stenosis, mark the length of the stenosis on the body surface, turn on the X-ray fluoroscope when the stent-bearing device is delivered to the corresponding position, adjust the stent to between the marks and release the stent. In the latter case, an ultra-fine bronchoscope is used to enter the airway while the stent inserter is feeding the stent into the lesion, and when the stent reaches the intended position, the stent is released under direct vision and the inserter is withdrawn. In general, the stent placement site should be over but not under. (3) Handling after stent placement: When the stent is withdrawn from the stent inserter, bronchoscopy is performed, and if the stent position is found to be inappropriate, the stent can be adjusted by using biopsy forceps to clamp the stent. (3) Observation after placement: Observe the patient’s vital signs, perform X-ray chest radiography regularly or when necessary, apply expectorant drugs, and apply cough suppressants when coughing is obvious. Complications】 1.Stent intracavitary tumor or granulation tissue proliferation causing restenosis. 2.Stent dislocation. 3.Stent mechanical damage such as fracture, disintegration, etc. 4.Infection, mucus plug, asphyxia, etc. 5.Stent embedding, penetration of airway wall, etc. Precautions】 1.Stents are foreign bodies, and there is no perfect stent yet, so you should weigh the pros and cons and choose carefully when placing stents. 2. In non-emergency situations, the best method to restore the airway opening should be used as much as possible. For example, when the cause of obstruction in the airway is tumor, if time and technology permit, the first choice of external radiotherapy, laser, microwave, electrocautery, argon knife or cryotherapy. 3.One of the difficulties in stent placement is to choose the right size stent. 4.Expandable metal airway stents are an important advancement in the treatment of airway stenosis, but since there are no large-scale clinical studies to compare the effectiveness and superiority with other methods of treating airway obstruction, time and large-scale clinical studies are needed to further demonstrate this.