Causes of functional intestinal obstruction
A paralytic ileus is caused by a functional disorder of the intestine and is also called intestinal paralysis. This means that the intestine is continuous and not interrupted by a mechanical obstacle. A further distinction is made between primary and secondary paralytic ileus.
The reason for a primary functional ileus is an obstruction of the vessels that supply the small intestine or the large intestine. The cause of vascular occlusion can be vascular thrombosis (a blood clot forms in the vessel) or embolism (the vessel is closed by material that has been infiltrated, e.g. a fat plug). Due to the occlusion, the blood flow is interrupted and the intestinal muscles are no longer supplied with sufficient oxygen and nutrients.
As a result, the intestinal wall loses its tension and can no longer transport the intestinal contents. In rare cases, the blood supply can also be interrupted by a large haematoma or a tumour that compresses the vessels. A secondary paralytic ileus can occur reflexively in the abdomen after surgery (especially laparotomies), blunt trauma or inflammation (such as in the context of peritonitis or blood poisoning).
However, certain drugs, such as opiates or certain antidepressants, can also cause functional intestinal obstruction. In addition, a mechanical ileus in the final stage always turns into a paralytic ileus. This is caused by the massive release of toxins produced by the uncontrolled multiplication of bacteria in the standing bowel contents.
Causes in the baby
A common cause of intestinal obstruction in babies and small children is the invagination. In this case, a section of the intestine is inverted into the part behind it. As a result, the intestinal contents accumulate and a mechanical intestinal obstruction is formed. The intestinal invagination is moved back again during an operation.
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