Malrotation

Question 1

Embryology

Answer 1

🌝During the sixth week of fetal development, the midgut grows too rapidly to be accommodated in the abdominal cavity and therefore herniates into the umbilical cord. Between the tenth and twelfth weeks, the midgut returns to the abdominal cavity, undergoing a 270° counterclockwise rotation around the superior mesenteric artery.
🌚 Genetic mutations likely disrupt the signaling critical for normal intestinal rotation.

Question 2

Epidemiology and Risk Factors

Answer 2

1:500 live births 1/3 present by 1 wk of age, 3/4 by 1 mo of age, 90% by 1 yr of age M:F = 1:1; higher incidence among patients with cardiac anomalies, heterotaxy syndromes

Question 3

Pathophysiology

Answer 3

• When rotation is incomplete or otherwise abnormal, “malrotation” is present. Incomplete rotation occurs when the cecum stops near the right upper quadrant and the duodenum fails to move behind the mesenteric artery; this results in an extremely narrow mesenteric root (see Fig. 129.1B) that makes the child susceptible to midgut volvulus, causing intestinal obstruction or mesenteric artery occlusion and intestinal infarction
• It is also common for abnormal mesenteric attachments (Ladd bands) to extend from the cecum across the duodenum, causing partial obstruction.

Question 4

Clinical

Answer 4

• Abdominal Pain Vomiting Gastrointestinal Bleeding 🩸
• Bilious emesis is the cardinal sign, especially if abdomen nondistended If bilious emesis in ill child with distended abdomen, consider surgical exploration to rule out volvulus Rectal bleed (late/ominous signs) Intermittent symptoms

Question 5

Laboratory and Imaging Studies

Answer 5

• Plain abdominal x-rays generally show evidence of obstruction.
• Abdominal ultrasound may show evidence of malrotation.
• An upper gastrointestinal (GI) series shows the absence of a typical duodenal “C-loop,” with the duodenum instead remaining on the right side of the abdomen.
• Abnormal placement of the cecum on follow-through (or by contrast enema) confirms the diagnosis.
• Laboratory studies are nonspecific, showing evidence of dehydration, electrolyte loss, or evidence of sepsis.
• A decreasing platelet count is a common indicator of bowel ischemia.

Question 6

Tx

Answer 6

1-IV antibiotics
2-Fluid resuscitation
3-EMERGENT LAPAROTOMY
Ladd procedure: counterclockwise reduction of midgut volvulus, division of Ladd’s bands, division of peritoneal attachments between cecum and abdominal wall that obstruct duodenum, broadening of the mesentery (open folded mesentery like a book and divide congenital adhesions), ± appendectomy Positioning the bowel into non-rotation (SBO in right abdomen, LBO in left abdomen)