What is the medical term for a twisted bowel causing ischemia, necrosis, and requiring surgical resection?

Volvulus: The Medical Term for Twisted Bowel

The medical term for a twisted bowel causing ischemia, necrosis, and requiring surgical resection is "volvulus." This condition occurs when a segment of intestine twists around its mesenteric axis, leading to vascular compromise and bowel obstruction 1.

Pathophysiology of Volvulus

Volvulus causes a cascade of vascular compromise that rapidly progresses to bowel death. The twisting mechanism creates both arterial and venous obstruction:

• Torsion beyond 180° leads to colonic obstruction, ischemia, or necrosis with perforation 1
• The subsequent colonic distension increases intraluminal pressure, which decreases capillary perfusion 1
• Mural ischemia is further aggravated by meso-colic vessel occlusion from mechanical compression and axial rotation 1
• Early mucosal ischemia promotes bacterial translocation and gas production, creating a vicious circle of increasing distension and toxicity 1

Anatomical Locations

Sigmoid volvulus is the most common type, followed by cecal volvulus, with small bowel volvulus being less frequent 2:

• Sigmoid colon is the most commonly affected segment, typically occurring in patients with an elongated sigmoid colon (dolicho-sigmoid) on a narrow mesenteric base 1
• Cecal volvulus represents the second most common cause of large bowel volvulus and requires different management 1, 3
• Small intestinal volvulus can occur around the superior mesenteric artery, though this is extremely rare 4

Clinical Presentation and Diagnosis

The classic triad consists of abdominal pain, distension, and constipation 5:

• Nausea and vomiting occur in 35-44% of patients 6
• Diarrhea may be present in 35% early in the disease process before complete ileus develops 6
• Abdominal distention indicates advanced disease with likely irreversible intestinal ischemia and bowel necrosis 6

CT imaging is essential for diagnosis, showing characteristic findings:

• The "coffee bean sign" or inverted U-shape for sigmoid volvulus 5
• The "whirl sign" representing spiraled loops of collapsed bowel 3
• Intestinal distention indicating impaired motility 6

Management Requiring Resection

When bowel necrosis is present, prompt surgical resection is mandatory 1:

• Urgent sigmoid resection is indicated when endoscopic detorsion fails or when non-viable or perforated colon is present 1
• Intraoperatively, resection of infarcted bowel should be performed without detorsion and with minimal manipulation to prevent release of endotoxin, potassium, and bacteria into circulation 1
• For cecal volvulus, endoscopy has no role, and surgery (right hemicolectomy) is the only option 1

The surgical goals include 1:

1. Re-establishment of blood supply to ischemic bowel
2. Resection of all non-viable regions
3. Preservation of all viable bowel

Prognosis

Mortality approaches 70-80% despite treatment when ileus is clinically obvious with distention 6:

• Early diagnosis before ileus develops is essential for survival 6
• The high mortality reflects delayed diagnosis, as patients initially present with abdominal pain and few findings 1
• By the time diagnosis is obvious due to distention, perforation, or shock, ischemia is far advanced 1

Critical Pitfall

The most common pitfall is delayed diagnosis due to initially subtle presentation. Volvulus should be suspected in any patient with the triad of abdominal pain, distension, and constipation, particularly in those with risk factors such as chronic constipation, high fiber diet, neuropsychiatric issues, or prolonged bed rest 1. Prompt CT angiography is essential to establish the diagnosis before irreversible bowel necrosis occurs 1.