NMS. Casos Clínicos

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Chapter 8 ♦ Lower Gastrointestinal Disorders

On initial evaluation, it is found that the patient is stable, with a blood pressure (BP) of 140/85 mm Hg (baseline). There is a WBC count of 15,000/mm 3 and no acidosis. Q: What is the next step? A: Based on the initial findings, a suspicion of ischemic bowel is appropriate. Two approaches are possible. 1. Proceed to the operating room if you think the patient has necrotic bowel. 2. Perform further evaluation prior to a management decision. In this case, because the patient appears stable and has no strong evidence for necrosis, further evaluation is most likely safe. While proceeding with aggressive resuscitation, ensure that the patient is well oxygenated and perfused, and continue with the workup. When a patient presents with pain out of proportion to physical examination findings, then mesenteric ischemia should be suspected. An emergent CT angiogram or formal angiogram should be performed if mesenteric ischemia is suspected. The patient undergoes an angiogram, which shows chronic occlusion of the celiac artery and superior mesenteric artery (SMA) with collateral formation inducing ischemia (Fig. 8-7). Clinically, the patient improves after antibiotics and hydration. Q: What is the next step? A: The patient has most likely had an ischemic event that has resolved for the time being but is likely to recur . The next episode could be worse, resulting in intestinal necrosis. You have established an anatomic abnormality on angiogram. Repair of this defect would most likely prevent a recurrence of ischemia. The patient should undergo an urgent revascularization of the mesenteric circulation. The patient undergoes revascularization successfully.

A C Figure 8-7: A: Preoperative lateral aortogram demonstrates total occlusion of the celiac and superior mesenteric arteries. B: Anteroposterior view with selective injection demonstrates large inferior to superior mesenteric artery collateral flow. C: Postoperative angiography demonstrates widely patent celiac and superior mesenteric arteries after transaortic endarterectomy. (Reprinted with permission from Mulholland MW, Lillemoe KD, Doherty G, et al. Greenfield’s Surgery , 5th ed. Philadelphia: Lippincott Williams & Wilkins; 2010.) SAMPLE B