Volvulus – causes, symptoms, diagnosis, treatment, pathology

The term volvulus actually comes from the
Latin word volvere, which means “to roll”. So a volvulus is an obstruction caused by
a loop of the intestine that rolls or twists around itself and its surrounding mesentery,
which is the tissue that attaches the intestine to the back wall of the abdomen. The three most common types of volvulus are
a sigmoid volvulus, which happens in the the last part of the large intestine, leading
to the rectum; a cecal volvulus, which happens in the beginning of the large intestine, and
a midgut volvulus, which happens in the small intestine. Now, a sigmoid volvulus is the most common
type of volvulus, and it can happen in a variety of settings. One classic one being pregnancy, because the
growing fetus can cause displacement and twisting of the colon. It can also develop, though, in middle-aged
and elderly individuals. This can sometimes happen as a result of chronic
constipation, where a big load of stool can act like a pivot point around which the rest
of the colon can twist. Hirschsprung disease, a disease of the large
intestine that causes severe constipation or intestinal obstruction, therefore raises
the risk for developing sigmoid volvulus. In addition, there are also abdominal adhesions,
where internal scar tissue creates a physical attachment between two parts of the abdomen,
which again serves as a pivot point around which the colon can twist. A cecal volvulus is usually found in young
adults, and usually happens in individuals who didn’t develop their abdominal mesentery
normally during fetal development. Since some mesentery contacts may be missing
in these individuals, the colon can flop around freely and any large object—like a baby
in pregnancy or a load of stool in someone constipated—can act as a pivot point in
the cecum and cause the colon to twist. Midgut volvulus is most commonly found in
babies and small children and is the result of abnormal intestinal development in fetuses. In normal fetal development, the digestive
tract starts as a straight tube from the stomach to the rectum. For a little while, a part of the intestine
protrudes from the abdomen into the umbilical cord. Once the fetus reaches around 10 weeks, though,
the intestine pulls back out of the umbilical cord, and returns to the abdominal cavity
and makes two turns, so that it is no longer a straight tube. Malrotation happens when the cecum and appendix,
which are normally found in the lower right side of the abdomen, stay in the upper right
side. Babies with malrotation can later develop
twisting of the small intestine, which is a midgut volvulus. In any type of volvulus, a portion of the
intestines becomes twisted and it pinches the lumen shut and results in bowel obstruction,
which prevents the normal passage of digested food and water. Sometimes, the mesentery can become so tightly
twisted that blood flow to that part of the intestine is cut off, which leads to infarction,
or death of the intestinal wall. This can cause a variety of symptoms ranging
from mild bloating and constipation to severe pain and bloody stools. In fact, bowel infarction can also cause the
intestinal wall to break down and allow the bacteria in the gut to move into the body,
which causes sepsis and the potential for cardiovascular collapse. Abdominal x-rays are usually used to diagnose
volvulus. These x-rays show the shape of the volvulus,
which can look like a bent inner tube or a coffee bean. A barium enema can also be used to show a
bird’s beak shape, enlarged at one end and tapered at the other end, which is the point
where the bowel is twisted. A sigmoid volvulus is usually treated with
sigmoidoscopy, an examination of the sigmoid colon using a set of flexible tubes inserted
through the anus. If the tissues look normal and pink, the tubes
untwist and decompress the colon to relieve pressure. A similar procedure that goes a bit further
in, called a colonoscopy, examines the entire colon and can occasionally be used to resolve
a cecal volvulus. But a midgut volvulus can’t be treated with
colonoscopy, since it’s even further back in the small intestine. Normally surgery is recommended within two
days of receiving treatment, or, in some cases, surgery should be performed immediately, like
if the bowel is severely twisted or if the blood supply is cut off. The normal surgical procedure involves untwisting
the intestine, if it hasn’t been corrected yet, and attaching the intestine up against
the abdominal wall to prevent it from twisting in the future. In severe cases, such as infarction, pieces
of the intestine have to be removed, a process called bowel resection, before the intestine
is reattached. Aright, as a quick recap: a volvulus is a
twist in the intestine and surrounding mesentery, and it’s most commonly found in the sigmoid
of middle-aged and older adults, the cecum of young adults, and the midgut, or small
intestine, of babies. Volvulus results in bowel obstruction and
can sometimes cause infarction, or death, of the bowel tissues. Volvulus is diagnosed using x-rays and is
usually treated with surgery to remove part of the bowel and attach the bowel up against
the intestinal wall. Thanks for watching, you can help support
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