During the 6th to 12th week of embryonic development, viral infections, metabolic disorders, local blood flow disorders or genetic factors may cause neurodevelopmental arrest or ganglion cell degeneration, resulting in spasm and stenosis of the distal segment of the intestine without ganglion cells and dilatation of the proximal segment of the intestine to form megacolon. What are the clinical manifestations of neonatal megacolon? Acute intestinal obstruction occurs within 1-6 days after birth. (1) Delayed fetal excretion: 90% of cases have no fetal excretion at birth or only very little fetal excretion. After the fetal stool is passed, the symptoms are relieved, and then the constipation symptoms recur after a few days. (2) Abdominal distension: 80% of cases show full abdominal distension, and in severe abdominal distension, intestinal shape is visible in the abdomen. (3) Vomiting: 60% of cases showed vomiting and abdominal distension, and the more severe the constipation, the more frequent the vomiting. (4) Anal examination: Anal finger examination can reveal spasm of the internal rectal sphincter and hollow rectal jug abdomen. (5) Comorbidity: combined with colitis, intestinal perforation is the most serious comorbidity, the long-term retention of large amounts of feces in the colon of the sick child, poor circulation of the intestinal wall and caused by bacteria. In addition, the thin intestinal wall of newborns, the pressure in the intestinal cavity increases, and the part that bears the greatest pressure is easy to cause perforation. Neonatal megacolon examination 1, medical history and signs More than 90% of children born without fetal stool within 36 to 48 hours after the birth, that is, stubborn constipation and abdominal distension must be enema laxative or plug anal suppository to defecate history, often malnutrition, anemia and loss of appetite, abdomen highly distended, and visible wide intestinal type, rectal palpation feel rectal pot abdomen empty, there is a blast-like exhaust defecation. 2.X-ray view: abdominal standing plain film mostly shows low colonic obstruction, barium enema lateral and anterior-posterior photos can be seen in the typical spastic intestinal segment and dilated intestinal segment, poor barium excretion function, 24 hours later there is still barium retention, if not timely enema wash out barium can form barium stone, combined with enteritis dilated intestinal segment intestinal wall is jagged performance. 3.Biopsy Take a small piece of tissue from the rectal wall submucosa and muscle layer more than 4cm from the anus, check the number of ganglion cells, lack of ganglion cells in children with megacolon 4.Anorectal manometry, measurement of reflex pressure changes in the rectum and anal sphincter can diagnose congenital megacolon and identify other causes of constipation, in normal children and functional constipation when the rectum is distended stimulation of the internal sphincter In normal children and functional constipation, when the rectum is stimulated by distension, the internal sphincter immediately undergoes reflex relaxation and pressure decreases, while in children with congenital megacolon, the internal sphincter does not relax but also undergoes significant contraction to increase the pressure. The amount and activity of both can be measured chemically 5 to 6 times higher than in normal children, which is helpful in the diagnosis of congenital megacolon and can be used in newborns. Treatment and care of neonatal megacolon The two common treatment options for neonatal megacolon are conservative therapy and surgical treatment. (1) Conservative treatment: Carefully take care of the child and make preparations for surgery. The purpose is to relieve the pain caused by abdominal distension and constipation, such as using anal dilation, warm saline cleansing bowel, taking laxative, maintaining water-electrolyte balance and nutrition. The anal canal should be inserted through the spastic section, so that the effect of bowel cleansing is satisfactory and the abdomen is flat and the muscles are relaxed. The child should be kept warm during intestinal lavage to prevent secondary pulmonary complications. (2) Surgical treatment: open or minimally invasive surgery. In 80% of our children, laparoscopic megacolon resection can be performed in one stage. (1) Colostomy. Colostomy is a way to overtake the megacolon crisis and then perform radical surgery at about 1 year of age. The indications are for children who are not suitable for first-stage radical surgery, such as poor general condition, and malnutrition. After the fistula, attention should be paid to protecting the skin around the fistula opening to be clean and dry, lying in a comfortable position, keeping warm, and feeding carefully. In recent years, the first-stage radical surgery has been used in the neonatal period with good results. Two weeks of preparation before surgery. This includes clean bowel washings, which are required until the abdomen is flat and soft, correction of malnutrition, and application of antimicrobial agents. There are different surgical procedures depending on the type of pathology, and laparoscopy completes the intra-abdominal operation. Neonatal megacolon surgery care 1, preoperative care Psychological care because of neonatal megacolon symptoms are obvious, the condition is heavy, manifested as abdominal bulge, abdominal wall veins, defecation difficulties, vomiting, etc., parents on the one hand, see their children tormented by the disease doubly heartbroken, hope that the medicine to the disease, on the other hand, do not understand the development of the disease, unfamiliar with the medical environment, the medical technology is not assured, mostly manifested as doubts, anxiety, fear, etc.. Fear, etc. At this time, we should do a good job of reassuring the family members with kind words and amiable attitude, and use our exquisite technology, excellent skills and recovered cases to dispel their worries and make them actively cooperate with the treatment with a good attitude. Intestinal preparation Dilation of the anus to induce defecation In order to relieve the symptoms, the anorectum is generally stimulated with soap bars and corkage to cause the child to defecate and reduce abdominal distension. Cleansing and bowel cleansing This is an important nursing measure as well as an effective conservative treatment for symptom relief. After dilation and defecation, choose an anal tube of suitable thickness and insert it from the anus, the depth must be more than the narrow segment, and the lavage solution should be isotonic saline with a temperature of 39-41℃, avoiding hypotonic solution to avoid water poisoning. Take the anal suction method, pay attention to the balance of the amount of irrigation fluid, and pay attention to the child’s face, complexion and abdomen during irrigation, and pay attention to keeping warm in winter. Generally, one week before the operation, start to wash the bowel, once a day. Improve the nutritional status of the child Most of the children have normal diet after bowel irrigation, and after a week of reasonable feeding, the nutritional status is obviously improved, and intravenous supplementation is given if necessary. Pre-operative preparation Assist the physician to do auxiliary examination, introduce the method of anesthesia, surgical method, the purpose and significance of skin preparation, and the time and purpose of diet abstinence. 2. Closely monitor the change of condition Due to the influence of anesthesia, own physiological characteristics and other factors, the condition of the child changes rapidly after surgery, and should be closely monitored. Immediately after returning to the room, the baby should be placed on the pillow, with the head on one side, shoulders elevated, face mask oxygenation, timely removal of oral secretions, cardiac monitoring, and continuous monitoring of heart rate, respiration, and oxygen saturation until stable. As the thermoregulation ability of neonates is weaker than that of adults, and the exposure time is longer during surgery, the body temperature of children often does not rise after surgery. If the body temperature does not rise after 1h, gradually adjust the temperature to 35℃, and check the body temperature every 15-30min, then gradually adjust the temperature to 30℃. Diet After 24-48h postoperative period, diet is prohibited, after that, a clear liquid diet is given, and breastfeeding is given after 72h. Observe whether the child has nausea and vomiting and abdominal distension after eating. Care of the perianal skin After the removal of the anal support tube, because of the relatively large and thin stools, stimulating the perianal skin, easily causing perianal skin redness and even erosion, so the care of the perianal skin is very important. After each stool, the skin should be washed with warm water, dried with a low-powered hair dryer, and disinfected with local topical povidone iodine to keep the perineum clean and dry. Continue to keep the perianal skin clean and dry, wash, blow dry and disinfect in time after stool. Dilation To prevent postoperative scar contracture and narrowing, which may cause defecation difficulties, generally start to dilate the anus half a month after surgery, once every other day in the first week, twice a week for 2 weeks in the second week, once a week in the fourth week, and once every 2 weeks until 3 months or 6 months after surgery. Follow up The follow-up examination will be held once at 2 weeks, 1 month, 3 months and 6 months after discharge, and if there is any discomfort, follow up.