Congenital tracheal diseases

　　The esophagus and respiratory tract originate from the anterior gut of the embryonic primitive gut during development. The primitive esophagus is located behind the respiratory organs. The gut is divided into three parts: the anterior gut, the middle gut, and the posterior gut. In the early stages, both the cranial and caudal sides of the gut are sealed. By the third weekend of embryogenesis, the pharyngeal membrane of the cranial side of the gut ruptures, connecting the anterior gut with the oral cavity. As the heart moves downward, the length of the esophagus increases rapidly. By the 21st to 26th day of embryogenesis, the lateral sides of the anterior gut show tracheoesophageal grooves, followed by epithelial growth forming the esophageal tracheal septum, separating the esophagus from the trachea. If the esophagus and trachea are not completely separated, and their lumens are相通, an esophageal tracheal fistula is formed. If the esophageal tracheal septum is posteriorly displaced or the anterior gut epithelium grows excessively into the esophageal lumen, an esophageal atresia is formed. In addition, in the early stages of esophageal development, some cells of the anterior gut separate from the esophagus and continue to grow, which can form esophageal duplication anomalies, mostly manifested as cysts near the esophageal wall, some of which communicate with the esophageal lumen.

　　There are few reports on the complications of this disease, mainly some postoperative complications. Now, a brief introduction is given to the postoperative complications of tracheotomy surgery:

　　1. Subcutaneous emphysema

　　Subcutaneous emphysema is the most common postoperative complication, related to excessive separation of the soft tissue in front of the trachea, or the external short and internal long incision of the tracheal incision, or the skin incision is too tight. The escaped gas from the tracheal tube can enter the subcutaneous tissue space along the incision, spread along the subcutaneous tissue, and the emphysema can reach the head, face, chest, and abdomen, but it is generally limited to the neck. Most of them can be absorbed spontaneously within a few days and no special treatment is needed.

　　2. Pneumothorax

　　When exposing the trachea, excessive and deep separation downward can damage the pleura, leading to pneumothorax.

　　3. Bleeding

　　Minor bleeding at the wound during surgery can be stopped by compression or filling with gelatin sponge for compression, if there is more bleeding, there may be vascular injury, the wound should be checked and the bleeding points ligated.

　　Congenital tracheal diseases present with varying degrees of obstructive dyspnea, wheezing during inhalation, difficulty in feeding, and delayed growth and development. In severe cases, the supraclavicular fossa, intercostal soft tissue, and subxiphoid soft tissue indent during inhalation. The symptoms mentioned above are exacerbated when respiratory tract infections occur. Tracheal atresia, tracheal stenosis, and tracheoesophageal fistula are relatively common. The following is a detailed description of them:

　　1. Tracheal atresia

　　Infants are cyanotic at birth and often require emergency tracheal intubation in the delivery room because of tracheal atresia. The tracheal tube often passes through the laryngeal fissure to the esophagus, and then through the connection between the distal trachea and the esophagus to reach the lungs. Although the patient breathes well, if the X-ray shows that the tracheal tube is inserted into the esophagus and the situation remains the same after repeated intubation, it should be suspected as this disease.

　　2. Tracheoesophageal fistula

　　This type can be divided into tracheoesophageal fistula and bronchoesophageal fistula. Although congenital anomalies are usually found in newborns, the former type may not be diagnosed until adolescence or even adulthood. Most cases have a history of long-term feeding cough or cough, often coughing up food particles, and occasionally complicated with bronchial dilation.

　　3. Tracheal stenosis

　　Children with congenital tracheal stenosis may not show clinical symptoms until adolescence, if the stenosis is not severe, including:

　　1. Shortness of breath and dyspnea may worsen during physical activity or when respiratory secretions increase.

　　2. As the degree of stenosis worsens, progressive dyspnea and wheezing during inhalation occur.

　　3. In severe cases of stenosis, there is simultaneous indentation of the supraclavicular fossa, intercostal soft tissue, and upper abdomen during inhalation (triple凹陷 sign).

　　Congenital tracheal diseases are a group of congenital diseases, hence there are no effective preventive measures. During surgery, strict caution should be exercised to prevent unnecessary harm to the child. If the tracheal lumen of infants and young children is small, postoperative mucosal edema can lead to tracheal obstruction, with extremely high mortality rates after surgery. Moreover, the anastomosis will still be narrower than the normal site when they grow up, so it is advisable to delay the surgical treatment as much as possible until they are adults.

　　There are many types of congenital tracheal diseases. According to different types, the common clinical manifestations are as follows:

　　1. X-ray tracheal断层 photography can detect stenotic trachea.

　　2. Endoscopy can detect the lesion site.

　　3. Tracheal iodine oil contrast examination is valuable for diagnosing tracheal stenosis and understanding the extent of the stenosis.

　　4. CT scan and barium swallow examination can be used to check for tracheoesophageal fistulas.

　　Infants with congenital tracheal diseases generally have poor suckling ability, are prone to wheezing, and are easy to choke or vomit, so the following methods should be used for feeding:

　　1. Try to breastfeed and adopt the method of small and frequent meals, feeding according to need.

　　2. Feed in segments, do not feed too much at one time, and give rest and exhaust several times in between.

　　3. It is best to feed the baby while holding it.

　　The treatment methods vary according to the different congenital diseases, and the specific introduction is as follows:

　　1. Tracheal stenosis

　　For those with mild stenosis, tracheal dilation can temporarily improve symptoms, or a catheter can be inserted through a tracheotomy, and partial tracheal resection and end-to-end anastomosis can be performed for short-segment tracheal stenosis or short-segment funnel-shaped stenosis. The tracheal cavity in infants is very small, and postoperative mucosal edema can lead to tracheal obstruction, with extremely high mortality rates, and the anastomosis is still narrower than the normal site after growing up. Therefore, it is advisable to postpone the surgery as much as possible until after the child grows up.

　　2. Tracheoesophageal fistula - Tracheoesophageal fistula repair surgery

　　The surgical process varies depending on the location and type of the fistula. Usually, the surgical incision is made in the right chest. Usually, the child's physical condition is very poor, and the surgery needs to be carried out in stages.

　　3. Tracheal atresia or defect

　　Children with the disease need to undergo surgery to remove scar tissue from the narrowed or defective areas, and need to relax the trachea at the laryngeal and cervical segments before performing end-to-end anastomosis. Note that surgery should be postponed as much as possible until after the child grows up.