INTESTINAL ATRESIAS

Intestinal atresias are the product of a late intrauterine mesenteric vascular accident (blood supply was not received by a portion of bowel) as attested by Louw and Barnard in 1955. They are equally distributed from the ligament of Treitz to the ileocecal junction. Colonic atresias are very rare. There is proximal bowel dilatation, with distal (unused) micro-bowel. The diagnosis is suspected with maternal history of polyhydramnios (the higher the atresia), bilious vomiting, abdominal distension and obstipation. KUB shows “thumb-size” dilated bowel loops, and barium enema a microcolon of disuse. Louw classified them into: Type I: an intraluminal diaphragm with seromuscular continuity. Type II: cord-like segment between the bowel blinds ends. Type IIIA: atresia with complete separation of blind ends and V-shaped mesenteric defect (see figure), the most commonly found. Type IIIB: jejunal atresia with extensive mesenteric defect and distal ileum acquiring its blood supply entirely from a single ileocolic artery. The distal bowel coils itself around the vessel, giving the appearance of an "apple peel"deformity. Type IV: multiple atresias of the small intestine. After preoperative stabilization (GI decompression, electrolytes disturbances’ correction, antibiotherapy, and normothermia), treatment consists of exploratory laparotomy, resection of proximal dilated intestine, and end to oblique anastomosis in distal jejuno-ileal atresias. Tapering jejunoplasty with anastomosis is preferred in proximal defects.