It is difficult to diagnose<unk>  early. Blood tests In a series of 58 patients with<unk>  due to mixed causes: * White blood cell count >10.5 in 98% (probably an overestimate as only tested in 81% of patients) * Lactic acid elevated 91% (probably an overestimate as only tested in 57% of patients) In very early or very extensive acute<unk> , elevated lactate and white blood cell count may not yet be present. In extensive mesenteric<unk> , bowel may be<unk>  but separated from the blood flow such that the byproducts of<unk>  are not yet circulating. During endoscopy A number of devices have been used to assess the sufficiency of oxygen delivery to the colon. The earliest devices were based on tonometry, and required time to equilibrate and estimate the pHi, roughly an estimate of local CO2 levels. The first device approved by the U.S. FDA (in 2004) used visible light spectroscopy to analyze capillary oxygen levels. Use during aortic aneurysm repair detected when colon oxygen levels fell below sustainable levels, allowing real-time repair. In several studies, specificity has been 83% for chronic<unk>  and 90% or higher for acute colonic<unk> , with a sensitivity of 71%-92%. This device must be placed using endoscopy, however. Findings on gastroscopy may include edematous gastric mucosa, and hyperperistalsis. Finding on colonoscopy may include: fragile mucosa, segmental erythema, longitudinal ulcer, and loss of haustrations Plain X-ray Plain X-rays are often normal or show non-specific findings. Computed tomography Computed tomography (CT scan) is often used. The accuracy of the CT scan depends on whether a small bowel obstruction (SBO) is present. SBO absent * prevalence of<unk>  23% * sensitivity 64% * specificity 92% * positive predictive value (at prevalence of 23%) 79% * negative predictive value (at prevalence of 23%) 95% SBO present * prevalence of<unk>  62% * sensitivity 83% * specificity 93% * positive predictive value (at prevalence of 62%) 93% * negative predictive value (at prevalence of 62%) 61% Early findings on CT scan include: *<unk>  mesenteric edema * Bowel dilatation * Bowel wall thickening *<unk>  mesenteric stranding * Evidence of adjacent solid organ infarctions to the kidney or spleen, consistent with a cardiac embolic shower phenomenon In embolic acute<unk> , CT-Angiography can be of great value for diagnosis and treatment. It may reveal the emboli itself lodged in the superior mesenteric artery, as well as the presence or absence of distal mesenteric branches. Late findings, which indicate dead bowel, include: * Intramural bowel gas * Portal venous gas * Free abdominal air Angiography As the cause of the<unk>  can be due to embolic or thrombotic occlusion of the mesenteric vessels or nonocclusive<unk> , the best way to differentiate between the etiologies is through the use of mesenteric angiography. Though it has serious risks, angiography provides the possibility of direct infusion of vasodilators in the setting of nonocclusive<unk> .
Intestinal ischemia
Bowel obstruction
Bowel infarction
Intestinal pseudo-obstruction
Splenic infarction
Short bowel syndrome
Gallstone ileus
Vesicointestinal fistula