Acute Abdomen Flashcards
What consists of the “acute abdomen series”?
Erect posterior-anterior chest radiograph and supine and erect or decubitus radiographs of the abdomen.
Air-fluid levels are seen in normal patients, commonly in the stomach, often in the small bowel, but never in what part of the colon?
Never in the colon distal to the hepatic flexure.
Normal gas in the abdomen is predominantly what?
Swallowed air
Normal air-fluid levels in the small bowel should not exceed how many cm in length?
2.5 cm in length
The normal colon contains some gas and fecal material and varies in diameter from how many cm?
3 to 8 cm
Small bowel is dilated when it exceeds how many cm in diameter?
2.5 to 3.0 cm
The colon is dilated when it exceeds how many cm in diameter?
5 cm
Cecum is dilated when it exceeds how many cm in diameter?
8 cm
Adynamic ileus typically demonstrates what findings?
Diffuse symmetric , predominantly gaseous, distension of bowel.
The small bowel, stomach, and colon are proportionally dilated without abrupt transition.
More bowel loops are dilated than obstruction.
Postoperative adynamic ileus usually resolves in how many days?
4 to 7 days
This refers to a segment of intestine that becomes paralyzed and dilated as it lies next to an inflamed intraabdominal organ.
Sentinel loop
It is a manifestation of fulminant colitis characterised by extreme dilation of all all or portion of the colon.
Im this state, peristalsis is absent and the large bowel loses all tone and contractility.
Toxic megacolon
What is the most common cause of toxic megacolon?
Acute ulcerative colitis
Most striking finding of a toxic megacolon?
Dilation of the transverse colon up to 15 cm diameter.
When is the diagnosis of toxic megacolon suggested?
The diagnosis is suggested when the diameter of the colon exceeds 5 cm and the mucosa appears abnormal.
Toxic megacolon mortality percent
20%.
The bowel wall becomes becomes a “wet blotting paper”, and risk of perforation is extreme.
This means stasis of bowel contents above a focal lesion.
Mechanical bowel obstruction
Mechanical bowel obstruction may be due to what processes?
May be due to obturation (occlusion of mass in the lumen), stenosis due to intrinsic bowel disease, or compression of the lumen by extrinsic disease.
What is the goal of imaging in mechanical bowel obstruction?
To confirm the presence of obstruction, identify its level, and demonstrate its cause.
Radiographs can confirm the presence of bowel obstruction how many hours before the diagnosis can usually be made clinically?
6 to 12 hours
Most strangulation obstructions are closed-loop obstructions, which means what?
Blockage of a bowel loop segment at both ends. This occurs with incarcerated hernias and volvulus.
Gas within the parenchyma of solid organs or within the wall of hollow viscera may represent what disease processes?
Infection, fistula, infarction, or recent surgery or instrumentation.
Term applied to necrotising fasciitis of the perinuem, perianal and genital regions.
Fournier gangrene
Radiographs and CT findings of Fournier gamgrene are:
Bubbles and streaks of gas in affected soft tissues.
