What is the pathophysiology of volvulus?


What is the pathophysiology of volvulus?

Pathophysiology — Sigmoid volvulus occurs when an air-filled loop of the sigmoid colon twists about its mesentery. Obstruction of the intestinal lumen and impairment of vascular perfusion occur when the degree of torsion exceeds 180 and 360 degrees, respectively [24].

What is the pathophysiology of diverticular?

The development of diverticula in the colon typically occurs in parallel rows between the taenia coli. The pathogenesis of the disorder involves three major areas: (1) structural abnormalities of the colonic wall, (2) disordered intestinal motility, and (3) deficiencies of dietary fiber.

What are the complications of volvulus?

If untreated, volvulus can cause bowel strangulation, gangrene, perforation, and peritonitis. Complications of surgery include the following: Recurrence (if conservative surgery is performed)

What are the risk factors for sigmoid volvulus?

Predisposing factors to sigmoid volvulus include chronic constipation, megacolon, and an excessively mobile colon. Plain abdominal radiographic findings are usually diagnostic.

What is looping of the sigmoid?

What is looping? During colonoscopy, looping is a frequent challenge. It occurs when the colonoscope s. tretches and distends the colon in response to the physician’s efforts to advance the scope forward. Typically once a loop has formed, it must be straightened before the procedure can continue.

Why are cecal and sigmoid volvulus more common?

Volvulus can develop in any portion of the large bowel. However, it is most common in the sigmoid colon because of the mesenteric anatomy. Less commonly, volvulus develops in the right colon and terminal ileum (cecal or cecocolic volvulus) or the cecum alone (termed a cecal bascule).

Why does sigmoid colon cause diverticulitis?

Diverticula usually develop when naturally weak places in your colon give way under pressure. This causes marble-sized pouches to protrude through the colon wall. Diverticulitis occurs when diverticula tear, resulting in inflammation, and in some cases, infection.

Why is the sigmoid colon susceptible to diverticulitis?

Pulsion diverticula occur most frequently in the sigmoid colon because the lumen of the colon is the narrowest resulting in the generation of the highest pressures.

Why is sigmoid volvulus serious?

This situation can lead to death of the blood-starved tissue and tearing of the intestinal wall—a life-threatening event and a medical emergency. Sigmoid volvulus—twisting of the sigmoid colon—accounts for the majority of cases, with cecal volvulus—twisting of the cecum and ascending colon—occurring less frequently.

How is sigmoid volvulus diagnosis?

Plain abdominal radiographic findings are usually diagnostic of sigmoid volvulus. Decompression may be achieved by the introduction of a stiff tube per rectum, aided by endoscopy or fluoroscopy. A single-contrast barium enema examination is usually adequate if it is required, as in cases when the diagnosis is in doubt.