Congenital intestinal atresia and stenosis

　　1. Incomplete intestinal cavitation during the solid phase of embryonic development can lead to intestinal atresia or stenosis.

　　2. Blood supply disorders in a part of the fetal intestinal tract, such as intestinal torsion, intussusception, meconium peritonitis, adhesive intestinal obstruction, intestinal perforation, internal hernia, and malformation of mesenteric blood vessels, causing blood supply disorders in a part of the intestinal tract, leading to necrosis, absorption, and repair of the intestinal tract and forming intestinal atresia. Beijing Children's Hospital has seen 7 cases of intestinal atresia, where the intestinal lumen of the excised specimen showed intussusception changes, and multiple cases of intestinal atresia complicated with intra-abdominal adhesions and scattered calcification foci have been observed. Congenital intestinal atresia is most common in the lower segment of the jejunum and ileum, followed by the duodenum, while colonic atresia is less common. Intestinal stenosis is most common in the duodenum, and less common in the ileum. There are two pathological forms of intestinal atresia: one is membranous atresia, where a septum in the intestinal lumen divides the lumen, most commonly seen in the duodenum and jejunum, maintaining its continuity. The other form is that the appearance of the intestinal tract loses its continuity, or is only connected by a fibrous cord, with both ends of the obstructed intestinal tract presenting as blind ends, most commonly seen in the lower end of the jejunum and ileum. Single atresia is more common, and multiple atresia accounts for about 7.5% to 20%. The proximal part of the atresia due to long-term obstruction becomes dilated, with a diameter of up to 3-5 cm, and the intestinal wall thickens, which may also cause local anemia, necrosis, and perforation. The distal part of the intestinal tract becomes small and thin, with a diameter of 4-6 mm, no air in the lumen, and only a small amount of mucus and shed cells. If intestinal atresia occurs after meconium formation, there may be a small amount of black-green meconium in the distal atresia.

　　Congenital intestinal atresia often occurs with other congenital malformations, such as congenital anal atresia, congenital esophageal atresia, congenital heart disease, hypospadias, etc. The proximal part of the intestinal tract atresia due to long-term obstruction becomes dilated, with a diameter of up to 3-5 cm, and the intestinal wall thickens, which may also cause local anemia, necrosis, and perforation. The length of the small intestine in children with intestinal atresia is significantly shorter than that of normal newborns, usually 100-150 cm, while the normal length is 250-300 cm.

　　Congenital intestinal atresia and stenosis are characterized by vomiting, which occurs within a few hours to 1-2 days after birth, with frequent vomiting, large amounts, and most cases with bile in the vomit. A few cases have old, blood-stained vomit, with no normal meconium excretion, or only a small amount of gray-green jelly-like stool. High-positioned atresia or stenosis generally does not cause abdominal distension, but only slight fullness in the upper abdomen; low-positioned atresia or stenosis results in marked abdominal distension, and even visible intestinal loops. Severe vomiting can lead to dehydration, acid-base imbalance, and electrolyte disorders. An abdominal X-ray film shows 2-3 fluid levels in the stomach and duodenum in high-positioned atresia or severe stenosis, while the jejunum is not aerated; in low-positioned atresia or severe stenosis, many dilated intestinal loops and fluid levels can be seen.

　　The etiology of this disease is not yet clear, and it may be related to environmental factors, genetic factors, dietary factors, and emotional and nutritional factors during pregnancy. Therefore, it is not possible to prevent this disease directly based on the etiology. Early detection, early diagnosis, and early treatment are of great significance for indirect prevention of this disease, and can also reduce the occurrence of complications. For patients who have already been diagnosed with this disease, surgery should be performed as soon as possible to minimize complications.

　　The clinical symptoms of congenital intestinal atresia and stenosis are not typical, and abdominal X-ray examination can be seen, with intestinal air and liquid surface. The diagnosis can be confirmed by barium enema or nasal feeding barium contrast after barium enema or nasal feeding barium contrast.

　　1. Suitable semi-liquid foods include

　　Minced meat porridge, vegetable porridge, egg flower porridge, noodle soup, noodle slice soup, wonton, bread; steamed egg custard, egg flower soup, fried eggs; milk, yogurt; soft tofu, tofu pudding; fruit juice, puree, jelly; watermelon, ripe banana; vegetable puree, vegetable juice, tender chopped vegetable leaves; various meat soups, tender strips of meat, minced meat, fish slices, etc.

　　2. Foods to be avoided

　　Beans, soybeans, large vegetables, a large amount of meat, steamed dumplings, fried foods such as smoked fish and fried balls should not be eaten; steamed rice, pan-fried cakes, etc., are hard and not easy to digest and absorb, so they should be eaten less or not at all; spicy seasonings and other seasoning should not be eaten either.

　　This disease is generally treated by surgery, and preoperative preparation should be done well, such as attention to blood volume supplementation, correction of water and electrolyte imbalance, gastrointestinal decompression, administration of vitamin K and antibiotics, and supportive therapy, etc.

　　1. In the case of atresia or stenosis of the transverse segment of the duodenum, a duodenojejunal side-to-side anastomosis should be performed. If the lesion is in the first segment of the duodenum, a gastrojejunal anastomosis can be performed.

　　2. In the case of atresia or stenosis of the small intestine, the affected intestinal segment is resected and end-to-end anastomosis is performed.

　　3. In the case of atresia or stenosis of the colon, the affected intestinal segment is resected and anastomosed in one stage. If the child's overall condition is poor, the affected intestinal segment can be placed in an abdominal exterior fistula for the second stage anastomosis.