Viscera (heart, lungs, liver, gastrointestinal tract)
Jejunum
Jejunum
- Origin
- Begins at the duodenojejunal flexure in the left upper quadrant
- Insertion
- Continues seamlessly into the ileum in the lower abdomen
- Function
- Primary site for absorption of carbohydrates, proteins, lipids, electrolytes, and water across dense plicae circulares and villi
- Innervation
- Superior mesenteric plexus (sympathetic T9-T11, parasympathetic vagus nerve)
- Movement & chain
- Vigorous segmentation and peristaltic clearance
- Palpation
- Palpation of umbilical and left upper abdominal regions; auscultation of active bowel sounds
- Clinical
- Celiac disease (autoimmune villous atrophy causing malabsorption and chronic diarrhea), small bowel obstruction (SBO from postoperative adhesions), acute mesenteric ischemia.
- Segmental innervation
- T9-T11 spinal cord levels (periumbilical visceral pain)
- In clinical practice
- Auscultation of bowel sounds (hypoactive, hyperactive high-pitched tinkles, or absent), nasogastric tube drainage in small bowel obstruction, total parenteral nutrition (TPN) management in short bowel syndrome
- Region in the model
- Viscera (heart, lungs, liver, gastrointestinal tract)