FIGURE 116.5 A: Small bowel obstruction Numerous dilated small bowel loops occupy the midabdomen and have a stepladder configuration Minimal air is seen in the rectum B: Same patient as in (A ) The upright abdominal roentgenogram shows numerous dilated loops in the small bowel with differential fluid levels in one loop indicating mechanical bowel obstruction Current Evidence In any child with persistent emesis, especially with bilious emesis, acute intestinal obstruction must be considered If the obstruction is high in the intestinal tract, the abdomen does not become distended; however, with lower intestinal obstruction there is generalized distension and diffuse tenderness, usually without signs of peritoneal irritation Only if the bowel perforates or vascular insufficiency occurs will signs of peritoneal irritation be present If complete obstruction persists, bowel habits may change, leading to complete obstipation of both flatus and stool All patients with suspected bowel obstruction should have radiographs of the abdomen in supine and upright (or lateral decubitus) views In patients with acute mechanical bowel obstruction, multiple dilated loops are usually seen Fluid levels produced by the layering of air and intestinal contents are seen in the upright or lateral decubitus radiographs ( Fig 116.5 ) Intussusception CLINICAL PEARLS AND PITFALLS