congenital intestinal atresia
Introduction
Introduction to congenital intestinal atresia Congenital intestinal insult (congenitalintestinalatresia) is a common digestive tract malformation of neonatal intestinal obstruction, which seriously threatens the lives of sick children. In the early years, the mortality rate of this disease is very high. In the past 20 years, the progress of etiology research, the improvement of diagnostic level, the improvement of technical operation, the good monitoring before and after surgery, especially the application of intravenous high nutrition, have significantly improved the survival rate. China Medical University reported that there were 97 cases of intestinal atresia and 46 cases of intestinal stenosis from 1960 to 1985. In the 1990s, the cure rate of intestinal atresia reached 80%-85%, intestinal stenosis reached over 95%, and the cure rate was significantly improved. . basic knowledge Sickness ratio: 0.05% Susceptible population: newborn Mode of infection: non-infectious Complications: dehydration, aspiration pneumonia, peritonitis, shock, neonatal congenital biliary atresia, congenital esophageal atresia, umbilical bulging, hypospadias
Cause
Cause of congenital intestinal atresia
(1) Causes of the disease
Have the following doctrine:
1. During the embryonic development stage, the intestine cavitation in the solid phase can produce intestinal atresia or stenosis.
2. Infant bowel injury and blood supply disorders such as fetal volvulus, intussusception, fetal fecal peritonitis and adhesions of intestinal narrowing, intestinal perforation, internal hemorrhoids, mesenteric vascular developmental malformation, etc., cause a certain blood vessel disorder in the intestine Intestinal atresia was caused by necrosis, absorption, repair and other pathophysiological processes of the intestine. Beijing Children's Hospital had seen 7 cases of intestinal atresia, and the intestinal intussusception was changed in the intestine of the resected specimen, and intestinal incision was combined with the abdominal cavity many times. A large number of experimental studies have also confirmed this theory in cases of internal adhesion and scattered calcification.
3. Family genetic factors have received widespread attention, especially multiple intestinal atresia and Apple-Peel atresia, all considered to be an autosomal recessive genetic disease.
(two) pathogenesis
Congenital intestinal atresia is most common in the lower jejunum and ileum, followed by duodenum, colonic atresia is rare, and intestinal stenosis is most common in the duodenum, less ileum, intestinal obstruction has two pathological forms as shown in Figure 1. Shown: One type is membrane-type atresia. There is a diaphragm in the intestine to block the intestinal cavity to form a latch. It is more common in the duodenum and jejunum. The appearance still maintains its continuity. A small number of duodenal membranes are locked when the diaphragm is affected. The proximal endoluminal pressure acts on the distal end of the intestine, such as the "wind bag". During surgery, it should be noted that the appearance of another type of intestine loses its continuity, or only one fiber cord is connected, and the intestines at both ends of the obstruction They are blind end, more common in the lower jejunum and ileum, single occlusion is more common, and there are multiple occlusions accounted for 7.5% to 20%. There is an apple skin-like atresia in this type, the atresia is located in the proximal jejunum, and the superior mesenteric artery develops. Abnormal, leaving only the first jejunum branch and right colon artery, the small intestine around the vascular branch showed a cut apple peel, the mesentery is not fixed, prone to intestinal torsion.
The proximal tubule of the atresia is dilated due to long-term obstruction, and the diameter can reach 3 to 5 cm. The intestinal wall is hypertrophy. Ischemia, necrosis and perforation can also occur. The diameter of the distal intestine is 0.4-0.6 cm. There is no gas in the cavity. There are a small amount of mucus and shedding cells. If the intestinal atresia occurs after the formation of the fetus, a small amount of black and green fetus can be seen at the distal end of the lock.
Intestinal atresia often complicated with other malformations, such as congenital anal atresia, congenital esophageal atresia, congenital heart disease, hypospadias, etc. The length of the small intestine in children with intestinal atresia is significantly shorter than normal newborns, generally 100 to 150 cm long, normal children It is 250 to 300 cm.
Prevention
Congenital intestinal atresia prevention
Do a good job in pregnancy care and genetic counseling, preventive measures refer to other birth defects, prevention should be from pre-pregnancy to prenatal:
1. Premarital medical examination plays a positive role in preventing birth defects:
The size of the effect depends on the examination items and content, mainly including serological tests (such as hepatitis B virus, Treponema pallidum, HIV), reproductive system tests (such as screening for cervical inflammation), general physical examination (such as blood pressure, electrocardiogram), and asking about family history of the disease. , personal past medical history, etc., do a good job in genetic disease counseling.
2. Pregnant women should avoid harmful factors as much as possible:
Including away from smoke, ethanol, drugs, radiation, pesticides, noise, volatile harmful gases, toxic and harmful heavy metals, etc., in the process of antenatal care during pregnancy, systematic screening of birth defects, including regular ultrasound, serology Screening, etc., if necessary, a chromosome check to take practical measures.
Complication
Congenital intestinal atresia Complications dehydration aspiration pneumonia peritonitis shock neonatal congenital biliary atresia congenital esophageal atresia umbilical bulging hypospadias
Often complicated by dehydration, acidosis, and aspiration pneumonia, peritonitis with peritonitis, pneumoperitoneum, shock, etc., and often complicated with other congenital malformations: such as biliary atresia, esophageal atresia, umbilical bulging, anorectal atresia, Merkel Diverticulum, intestinal duplication and other gastrointestinal malformations, multi-finger (toe), hypospadias, horseshoe kidney and other urinary malformations, and cardiovascular malformations such as congenital heart disease, small intestine atresia associated with congenital stupid.
Symptom
Congenital intestinal atresia symptoms Common symptoms constipation abdominal distension dehydration hair loss weakness thinning difficulty edema bowel
The clinical manifestations of congenital intestinal atresia or intestinal stenosis are mainly symptoms of intestinal obstruction, and the morning and evening and severity of symptoms depend on the location and extent of obstruction.
Intestinal atresia
Intestinal atresia is a complete intestinal obstruction, the main symptoms are vomiting, bloating and constipation.
(1) Vomiting: vomiting occurs more than after the first feeding or on the first day after birth. The morning and evening appear to be related to the atresia. The duodenum and high intestinal atresia occur frequently and frequently, while the ileum and colon Such low-level atresia can occur 2 to 3 days after birth. After vomiting, it is progressively aggravated, and the amount of vomiting is high. The case of high intestinal atresia is vomit, which contains bile, sometimes old blood, and after milk. Vomiting is aggravated, a small number of duodenum occurs above the common bile duct opening, there is no bile in the vomit, and low locus vomit can be fecal-like and smelly.
(2) Abdominal distension: Abdominal distension is a common sign of intestinal atresia. The degree of abdominal distension is related to the position of the atresia and the time of treatment. The higher the position of the general atresia, the earlier the treatment time, the lighter the degree of abdominal distension, and the heavier the opposite, the higher the locus In cases, abdominal distension is limited to the upper abdomen, and it is not serious. After a large amount of vomiting or after gastric tube extraction, the abdominal distension can disappear or be significantly alleviated. In the case of low atresia, the whole abdomen is uniformly expanded and progressively aggravated. After vomiting or withdrawing the contents of the stomach, there was no significant change in abdominal distension. Occasionally, gastric or gastric peristalsis was observed in the upper abdomen during high intestinal atresia, and dilated intestinal fistula was often seen in low intestinal atresia.
(3) Constipation: The absence of normal fetus discharge after birth is an important manifestation of intestinal atresia. Normal neonates discharge normal meconium within 24 hours after birth, which is dark green, except for stomach, intestine, liver, pancreas, etc. Exfoliated cells and exfoliated cells of the intestinal mucosa, there are still amniotic fluid swallowed by the fetus and keratinized cells of the skin. Intestinal atresia, no meconium is discharged after birth, and some only discharge a small amount of grayish white or blue-gray mucus. In order to block the secretions and exfoliated cells of the distal intestine, unlike normal meconium, it has been reported that a small amount of meconium may be excreted in individual sick children.
(4) General condition: In the first few hours after birth, the general condition of the sick child is no different from that of normal children, but soon it is manifested as restlessness, can not fall asleep, does not eat milk or sucks, is weak, due to frequent vomiting, appears soon Dehydration and poisoning symptoms, and often accompanied by aspiration pneumonia, the systemic condition deteriorates rapidly, such as intestinal perforation peritonitis, due to pneumoperitoneum, abdominal distension is more obvious, abdominal wall edema, redness and brightening, abdominal wall venous engorgement, bowel sounds Disappeared; and there are breathing difficulties, cyanosis, body temperature does not rise and systemic poisoning symptoms.
Enteral stenosis
The clinical symptoms of intestinal stenosis vary depending on the degree of stenosis. A few cases with significant stenosis have complete intestinal obstruction after birth, which is difficult to distinguish from intestinal atresia. Most of them have incomplete intestinal obstruction after birth. The clinical manifestations are repeated vomiting. The vomit is milk and bile. The meconium is excreted after birth, but the amount is less than normal. The degree of bloating depends on the stenosis: high stenosis is limited to the upper abdomen; lower stenosis is Total abdominal distension, because it is chronic incomplete intestinal obstruction, intestinal type and intestinal peristalsis are often seen in the abdomen, and bowel sounds are hyperthyroidism.
The prominent symptom of intestinal atresia is vomiting. The higher the atresia, the earlier the vomiting occurs. The vomit is the fed drink and the milk mass, with bile. The vomit of the low-level atresia is mostly stool-like. The baby presented with vomiting on the first feeding after the birth, and continued to have repeated vomiting and progressive exacerbation.
Defecation: Children with intestinal atresia have no normal meconium excretion, but more gray or blue-gray stool, but a small number of children have formed meconium in the late pregnancy, intestinal blockage caused by blood circulation disorder, can be discharged A little green fetus.
Early cases are generally in good condition. After multiple vomiting, they are thin, dehydrated, and the systemic condition deteriorates rapidly. In advanced cases, aspiration pneumonia is often secondary, and high intestinal intestine is inflated in the upper abdomen. Gastric peristaltic waves propelled from left to right can be seen. Low atresia The whole abdomen is inflated, and the intestinal type and intestinal peristalsis can be seen. For example, when the perforation of the intestine is accompanied, the abdominal distension is aggravated, and the vein of the abdomen is visible.
Examine
Examination of congenital intestinal atresia
Routine blood and blood biochemical tests, peritonitis, infectious blood in pneumonia, increased white blood cells, decreased hemoglobin and thrombocytopenia, blood biochemical examination of blood sodium, potassium, chlorine, calcium and blood pH, often water, electrolytes Disorder, may occur alkalosis, may have impaired renal function, such as elevated creatinine, elevated urea nitrogen.
In the past, many people have emphasized the use of the Farber test to examine the non-keratinized epithelial cells and fetal hair in meconium to diagnose intestinal atresia. It has diagnostic value for the formation of intestinal atresia within 3 months, but the middle and late fetuses are mechanical or blood vessels. Sexually induced intestinal atresia is not diagnostic, because the keratinized epithelium has dropped to the distal end of the atresia, and has rarely been used clinically in recent years because it is generally not difficult to determine the diagnosis of intestinal atresia based on clinical and X-ray examinations. In addition, the test is not completely accurate.
X-ray inspection
X-ray abdominal plain film is of great value in diagnosing intestinal atresia and intestinal stenosis. High intestine atresia in the abdomen upright position can show "three bubbles sign" or large liquid level and small liquid level, that is, a large liquid level (stomach) And 3 to 4 small liquid level (expanded jejunum), the lower abdomen is completely free of gas shadows, or shows more dilated intestinal fistula, the lower intestine atresia X-ray standing flat film shows multiple liquid level and dilated bowel Hey, but there is no gas shadow in the colon. Except for the extreme expansion of the most intestines, the caliber of other dilated intestinal fistulas is mostly uniform. There is no gas in the colon and rectum on the lateral radiograph, which is different from paralytic intestinal obstruction.
2. X-ray tincture examination
It is not appropriate to carry out barium meal examination for children with intestinal atresia because of the risk of causing aspiration pneumonia. However, for clinically atypical cases, it is necessary to perform barium enema examination, which can not only determine intestinal atresia according to fetal colon. Diagnosis, to determine whether the colon is locked, and can also exclude congenital megacolon or poor intestinal rotation.
Under the fluorescent screen of the barium enema or the film, the colon is small and the diameter is only about 5mm. In addition, the barium enema can identify the poor intestinal tract and congenital megacolon.
Cases of intestinal stenosis often require barium meal examinations to make the diagnosis clear. Under fluoroscopy, the expectorant is deposited in the obstruction site, and only a small amount of barium agent enters the distal intestinal lumen through the stenosis segment.
3. Prenatal B-mode ultrasound scan
It is valuable for the diagnosis of fetal small intestine atresia. High jejunal atresia shows an elongated liquid area extending from the stomach to the proximal end of the jejunum, or several expanded jejunal fluid areas in the upper part of the fetal peritoneal cavity.
Diagnosis
Diagnosis and diagnosis of congenital intestinal atresia
Inspection diagnosis
1. History and performance characteristics: 15.8%45% of small intestine atresia accompanied by polyhydramnios, especially jejunal atresia, the amount of amniotic fluid can exceed 2000-2500ml, and neonates with excessive amniotic fluid begin persistent vomiting after birth. , no normal meconium discharge or progressive abdominal distension, that is, the possibility of intestinal atresia should be suspected.
2. Anal examination: If you do anal finger examination and warm saline enema or 1% hydrogen peroxide solution enema still no normal meconium discharge, you can further exclude meconium constipation and congenital giant caused by meconium thickening The colon is very important.
3. Auxiliary examination: The characteristic changes of abdominal X-ray plain film have great value in diagnosis. High intestinal incision standing X-ray film can see 2 to 3 enlarged liquid level in the upper abdomen, other intestines are not inflated at all; low intestine Most of the obstruction can be seen to enlarge the intestinal tract and the liquid level. The barium enema can be seen as a small contracted fetal colon. Its characteristics are as follows: 1 diameter is about 0.5cm; 2 colonic creases are not obvious; 3 colon is straight and short.
Differential diagnosis
Congenital intestinal atresia needs to be differentiated from the following diseases: congenital megacolon, poor intestinal rotation, ring-shaped pancreas, etc., except by the results of barium enema.
