| disease | Colonic Volvulus |
| alias | Volvus of Cloln |
Colonic volvulus refers to a closed-loop intestinal obstruction caused by abnormal development of the colon, such as mobile colon, excessive length of the transverse colon, and redundant sigmoid colon, where a segment of the intestinal loop rotates along the axis of its mesentery. Mobile cecum occurs when the extraperitoneal portion of the cecum and ascending colon is replaced by a longer mesentery, remaining unfused with the lateral peritoneum and freely movable near the spine. It is classified into three grades: Grade I—cecum pushed to the right border of the spine, Grade II—anterior to the spine, and Grade III—left of the spine. The transverse colon or sigmoid colon may also become prone to torsion due to congenital elongation of the intestinal tube combined with a relatively short mesentery. When colonic contents rapidly increase, especially with sudden changes in body position or increased abdominal pressure, the elongated intestinal segment may rotate clockwise or counterclockwise along the mesentery, leading to mechanical intestinal obstruction. Generally, a 180-degree rotation is considered physiological and often results in simple intestinal obstruction, whereas a 360-degree rotation of the entire intestinal segment typically causes strangulated intestinal obstruction. Sigmoid volvulus is the most common type of colonic volvulus, predominantly affecting elderly males. Cecal volvulus is less common and can occur at any age, with a higher incidence between 20 and 40 years. Transverse colon volvulus, unless caused by adhesions, is rare.
bubble_chart Pathological Changes
Mobile cecal volvulus is mostly counterclockwise, while transverse colon volvulus is often caused by excessive bowel length and adhesions. Sigmoid colon redundancy can twist either clockwise or counterclockwise. In grade I volvulus, the twist may be less than one full turn (360°), whereas severe cases can involve two or three turns. During volvulus, the intestinal lumen becomes narrowed and obstructed, and the mesentery rotates with the bowel, compressing and occluding the mesenteric vessels, leading to intestinal strangulation. Since the obstruction occurs in the colon, it manifests as low intestinal obstruction. In cases of complete obstruction, the closed-loop segment may become severely distended, leading to local necrosis, perforation, and diffuse peritonitis. Colonic contents are alkaline, so initial peritoneal irritation may be mild, but due to the colon being a bacterial reservoir, peritonitis progresses rapidly and severely. If treatment is delayed, the prognosis is poor. Of course, milder cases of volvulus may resolve spontaneously, particularly in the sigmoid colon.
bubble_chart Clinical ManifestationsVolvulus of the cecum is a complication of mobile cecum, manifested as acute colicky pain in the right abdomen, accompanied by vomiting, abdominal distension and fullness, failure to pass gas or stool, and other typical symptoms of intestinal obstruction. A tender mass can often be palpated in the right middle or upper abdomen, with tympany on abdominal percussion, and varying degrees of peritoneal irritation signs may be present.
Volvulus of the transverse colon is mostly functional, presenting as acute abdominal pain in the upper abdomen, which improves after passing gas or stool. In contrast, volvulus caused by adhesions is often due to abdominal inflammation or surgery, with symptoms including colicky pain in the mid-upper abdomen, nausea, vomiting, and constipation. A distended large intestine with tenderness may be palpated in the mid-upper abdomen.
Sigmoid colon volvulus often occurs in patients with a history of recurrent left lower abdominal pain that improves after passing gas or stool, or a long-standing habit of constipation. During acute episodes, colicky pain in the left lower abdomen is accompanied by nausea and vomiting. A distended intestinal loop with mild tenderness may be palpated in the left lower abdomen, along with possible peritoneal irritation signs and tympany on percussion.
bubble_chart Auxiliary Examination
1. X-ray examination
Abdominal plain film: In cecal volvulus, the abdominal plain film may reveal a distended large intestine loop with gas or fluid levels in the right lower abdomen. Barium enema shows obstruction at the transverse colon. In sigmoid volvulus, the X-ray film may display a single, massively distended double-loop bowel extending from the pelvis to below the left diaphragm, occupying most of the abdomen or appearing as a "bird's beak" shape. Low-pressure saline enema can also aid in diagnosis. If less than 500ml of fluid can be infused (normally 3000–4000ml can be infused), it confirms obstruction in the sigmoid colon.
At the site of obstruction related to volvulus, narrowing may be observed. If the volvulus is non-strangulated, the colonoscope can be used to reduce the volvulus (care must be taken not to over-insufflate air to avoid increasing pressure in the closed-loop bowel). However, if peritoneal irritation signs are present or bowel strangulation is suspected, endoscopy must not be performed.
Based on typical medical history, signs, and X-ray examination, a diagnosis can generally be confirmed. However, the presence of intestinal strangulation should be assessed based on symptoms and signs to guide the treatment plan.
bubble_chart Treatment Measures
I. General Treatment
1. Fast and perform gastrointestinal decompression.
2. Administer fluids to correct typical edema and electrolyte imbalances.
3. Provide antibiotics to prevent infection.
II. Non-surgical Treatment
1. For early-stage colonic volvulus, fiberoptic colonoscopic reduction may be attempted, especially for sigmoid volvulus, which has a higher success rate.
2. In the early stages of sigmoid volvulus, the colonoscope can be inserted under direct vision to the obstruction site, typically 15–25 cm from the anus. If the mucosa at this site shows no necrosis or ulceration, a rectal tube approximately 60 cm long can be inserted through the sigmoidoscope. Care should be taken to avoid forceful insertion to prevent intestinal perforation. Once the tube passes the obstruction, loose stool and gas may forcefully discharge, providing immediate relief to the patient, which is a sign of successful reduction. To prevent recurrence, the rectal tube may be left in place for 2–3 days.
If non-surgical treatment fails for cecal volvulus or if strangulation is suspected, exploratory laparotomy should be performed as early as possible. The twisted cecum (along with the ascending colon and terminal ileum) should be examined. If no necrosis is present, reduction should be performed in the opposite direction of the twist. Then, the lateral posterior peritoneal membrane of the cecum should be incised, and its anterior edge should be intermittently sutured (3–5 stitches) to the lateral colonic band of the cecum. If the cecum is significantly dilated, 3–4 interrupted seromuscular sutures should first be placed along the starting points of the two colonic bands to narrow the cecal lumen before suturing and fixing the cecum to the lateral posterior peritoneal membrane. If intestinal strangulation and necrosis are present, a right hemicolectomy with ileotransverse colostomy should be performed. If there is significant peritoneal effusion, peritoneal lavage and rubber tube drainage must be performed to alleviate systemic toxic symptoms. Postoperative treatment should include high-dose antibiotics.
The principle for managing transverse colon volvulus is as follows: if it is a simple mechanical twist, adhesiolysis and reduction may suffice. If necrosis is present, resection of the necrotic segment, end-to-end anastomosis of the transverse colon, and necessary peritoneal drainage should be performed.
For sigmoid volvulus, if intestinal strangulation is suspected or if sigmoidoscopy reveals necrosis and ulceration of the twisted intestinal mucosa, prompt surgical intervention is required. During exploratory laparotomy, if the intestine is not necrotic, reduction and rectal decompression should be performed. If the twisted intestine is necrotic, the extent of necrosis and peritonitis should guide the decision to either perform resection with proximal colostomy and distal closure or primary anastomosis. For recurrent sigmoid volvulus, elective resection of the redundant bowel with initial-stage (first-stage) anastomosis should be considered. {|110|}
Timely treatment of colonic volvulus generally results in a good prognosis, but the outcome is poorer if there is intestinal strangulation or even rupture and perforation. If the management is deficient or inappropriate, the mortality rate is relatively high. After non-surgical treatment improves colonic volvulus, further investigation into the underlying cause should be conducted. If necessary, elective surgery can be performed to eliminate the disease cause and prevent recurrence.
1. Intestinal cancer
Cecal, transverse colon, sigmoid colon, or rectal intestinal cancer can all present with low intestinal obstruction, but the medical history is usually longer and often lacks a sudden abdominal pain history. The mass in intestinal cancer is hard with clear boundaries. In contrast, colonic volvulus involves distended intestinal loops, which feel softer and have indistinct boundaries upon palpation, making them easier to differentiate. Of course, a barium enema can confirm the diagnosis.
2. Intestinal intussusception
Ileum intussusception into the cecum is more common and can extend to the sigmoid colon. The onset is acute, presenting as low intestinal obstruction, mostly occurring in infants aged 5–6 months. Symptoms include paroxysmal crying, nausea, vomiting, and currant jelly-like stools. Palpation reveals emptiness in the right lower abdomen and a sausage-like mass in the right upper abdomen. A barium enema showing a cup-shaped shadow can confirm the diagnosis. Chronic intussusception in adults is rare and usually caused by tumors, making it clearly distinguishable from colonic volvulus.
