Small Intestine
Epiploic Foramen Entrapment
Basic Information 
Definition
• The epiploic foramen (foramen of Winslow) is bordered by the caudate liver lobe, forming the dorsal and craniodorsal border, the portal vein forming the cranioventral border, and the gastropancreatic fold forming the ventral border. The epiploic foramen is the entrance to the omental bursa.
• The small intestine can traverse the foramen and become entrapped, causing obstruction.
• The ileum is involved in 70% of cases with jejunal involvement in 40% to 60% of cases. The length of intestine involved is variable (8 cm–18 m) and increases with time. Multiple independent loops passing through the foramen can also be seen.
Clinical Presentation
Physical Exam Findings
• Moderate to severe abdominal pain. Initially responsive to analgesics; response diminishes as disease progresses.
• Cardiovascular status diminishes with progression of the disease. Signs of dehydration occur rapidly.
• As the disease progresses, horses may become depressed and show progressive signs of endotoxemia.
Diagnosis 
Initial Database
• Rectal examination early in disease often reveals no palpable small intestine because of the cranial location of the foramen. As the disease progresses, loops of distended small intestine become palpable. In the author’s experience, it is common to feel a concentration of distended small intestine “suspended” in the upper right quadrant of the abdomen.
• Nasogastric reflux (NGR) is seen as the disease progresses. NGR may be absent early in the disease. Pain relief may not be seen after decompression.
• Abdominocentesis is useful in distinguishing between a simple obstruction and strangulating obstruction. Peritoneal protein and nucleated cell count are often normal early in the disease process. As the colic progresses, peritoneal protein elevates. Only in late disease with increased intestinal injury does the peritoneal nucleated cell count increase. Fluid is often serosanguineous. Results of abdominocentesis may underestimate the true severity of the disease.
• Complete blood count and chemistry profile are normal early in the disease process. As the colic progresses, changes consistent with dehydration and endotoxemia occur rapidly. A mild metabolic acidosis may also be present.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
