Pediatric pulmonary sequestration

　　Pulmonary sequestration is a congenital malformation, referring to non-functional embryonic and cystic lung tissue. The etiology of this disease is unknown, and some believe that the isolated lung tissue may originate from an abnormal bronchus during the embryonic period. In the early embryonic stage, the primitive gut and lung bud are surrounded by many capillaries connected to the renal aorta. Because the capillaries connecting the isolated lung tissue are not absorbed, they can be considered as a branch of the aorta, becoming an abnormal artery that supplies the isolated lung. To date, there is no evidence that this disease is related to genetic factors, and some cases have abnormal pregnancy histories during the mother's pregnancy.

　　This disease often has recurrent or persistent progressive pulmonary infections. In addition to the common complications of lobectomy, the postoperative complications of pediatric pulmonary sequestration include:

　　1, Severe bleeding, mainly due to loose ligatures and suture line detachment causing vascular bleeding. Due to the high pressure of the aorta, bleeding from the residual end of the malformed vessels is often large and severe. This complication often occurs within 48 hours after surgery, presenting with signs of hemorrhagic shock such as rapid pulse, increased heart rate, and decreased blood pressure. A sudden increase in pleural drainage volume indicates significant bleeding in the pleural cavity. If such bleeding occurs, it often requires immediate reoperation to stop the bleeding.

　　2, Esophageal pleural fistula, this condition is rare, but once it occurs, the prognosis is poor. One of the reasons is that the esophagus is damaged during surgery, and the other is that the potential bronchial esophageal fistula is not found during the operation, and the residual end is not treated. If it occurs, it should be adequately drained, and chest surgery may be needed again if necessary.

　　3, Infants and young children, especially newborns, are not surgical contraindications, but such children often have other malformations and pulmonary hypoplasia, which are prone to water, electrolyte, and acid-base imbalance as well as pulmonary and systemic infections after surgery. Early postoperative ventilation support should be used for a period of time, and later, back blows should be given more often, and nebulizer inhalation may be necessary to promote sputum removal if needed.

　　Symptoms generally appear after secondary infection, especially common in the intralobar type, presenting as recurrent or persistent progressive pulmonary infections, resembling pneumonia or lung abscess, with chills, fever, chest pain, cough, sputum, hemoptysis, and weight loss. Extralobar infections are less common, often asymptomatic, and only discovered on X-ray examination as a mass in the pleural cavity. Preoperative X-ray examination may show abnormal shadows, but it is difficult to differentiate from pulmonary cysts and other lung diseases.

　　The extralobar type of pediatric pulmonary sequestration generally requires resection of the focus, while the intralobar type requires lobectomy, with good postoperative effects. The preventive measures for this disease include the following:

　　1, Get vaccinated on time.

　　2, Open the windows every day to ventilate and keep the indoor air fresh, especially in bedrooms, computer rooms, and study rooms.

　　3, Do not go to crowded places with poor air quality, such as dance halls, cinemas, and video halls.

　　4, Wash your hands frequently and clean them thoroughly with running water, including not using dirty towels to wipe your hands.

　　5, Wear a mask when visiting the hospital, wash your hands after returning home, and avoid cross-infection.

　　6, Be careful not to overwork and prevent colds to avoid a decrease in resistance.

　　7, Have a balanced diet and increase your nutrition.

　　8, Seek medical attention promptly if you have a fever or other discomfort.

　　9. Avoid contact with infectious patients and try not to go to epidemic areas of infectious diseases.

　　10. Properly disinfect items and rooms used by infectious patients, such as drying clothes and bedding in the sun, spraying and wiping the handles of doors in the room, and tables and floors with chlorine disinfectant.

　　Routine laboratory tests for pulmonary sequestration are not special. When there is infection, blood routine examination shows characteristics of infectious blood, and diagnosis mainly relies on imaging examinations. Chest X-ray can provide the initial clues for diagnosing PS. Ultrasound and color Doppler ultrasound have become common screening methods for PS, and most cases can be basically diagnosed by ultrasound and CT. Chest CT, because it can show abnormal blood supply arteries and substantial changes, has become an important detection method for diagnosing PS. Retrograde aortography, because it can judge the source of blood vessels, is of decisive significance for diagnosing PS, and identifying the origin, number, and course of the blood supply arteries is crucial for formulating surgical plans. Chest MRI can be imaged in multiple planes and has the effect of blood emptying, and it can display the blood supply arteries and return veins of PS without using contrast agents.

　　The postoperative effect of pulmonary sequestration is generally good. Pay attention to eating more fresh vegetables and fruits, such as green, yellow, red vegetables, as well as black fungus, almond juice, water chestnut, asparagus, lemon, jujube, garlic, etc. Avoid smoking, alcohol, and spicy刺激性 food. Avoid fried, grilled, sticky phlegm-inducing foods.

　　General consideration for surgical resection of pulmonary sequestration should include, especially in areas where inflammation is difficult to control, or recurrent attacks, or long-term chronic diseases, it is necessary to take timely surgical treatment. For intralobar type isolated lung, lobectomy should be performed, and for extralobar type isolated lung, it can be resected while preserving the rest of the lung. The main technical problem lies in the very fragile abnormal artery supplying the isolated lung, which is often hidden in adhesions and is prone to bleeding. Therefore, great care and meticulousness should be taken during surgery, and the postoperative effect is good. For extralobar type, it is generally sufficient to remove the focus, while for intralobar type, lobectomy is required, and the postoperative effect is good. During the operation, great care should be taken to find and properly handle the abnormal vessels in the lesion area to avoid uncontrollable bleeding and death.