NMS. Casos Clínicos

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Chapter 8 ♦ Lower Gastrointestinal Disorders

Case Variation 8.7.7. A hematocrit of 55% ◆ ◆ Polycythemia is most likely to be secondary to severe dehydration , which could be cor- rected by rehydration. Treatment involves rehydration. Although polycythemia vera is less common in older patients, it may also occur. It is a hypercoagulable state and, like other hypercoagulable conditions, can cause stasis, low flow, and thrombosis in the mesenteric vascular beds. Treatment of primary polycythemia consists of phlebotomy and hydration. Angiography should still be performed for operative planning. Polycythemia as a second- ary event may also be associated with COPD, and depending on the state of the patient, a pulmonary evaluation would be appropriate. Case Variation 8.7.8. History of congestive heart failure ◆ ◆ Congestive heart failure can be associated with low-flow states in the mesenteric circula- tion. An angiogram can confirm a low-flow nonocclusive state in a suspected combination of congestive heart failure and mesenteric ischemia. Treatment of this condition involves direct mesenteric infusion of a vasodilator such as papaverine and efforts to improve cardiac output. Case Variation 8.7.9. History of thoracic aortic dissection ◆ ◆ Aortic dissection can occlude any vessel orifice in the aorta. The combination of dissec- tion and mesenteric ischemia suggests an occlusion related to the dissection. Angiography allows for diagnosis and the planning of surgical correction. Case Variation 8.7.10. BP of 90/60 mm Hg (in the emergency department) ◆ ◆ The combination of suspected mesenteric ischemia and hypotension may indicate isch- emia, causing sepsis and hypotension, or hypotension, causing nonocclusive ischemia due to low flow. Overall patient assessment, measurement of hemodynamics, angiography, or surgery may be necessary to diagnose the problem correctly. Case Variation 8.7.11. Bloody diarrhea ◆ ◆ This suggests an ischemic segment of colon with necrosis of at least the mucosa and subsequent sloughing. The next step in evaluation is sigmoidoscopy to assess the colon. If full-thickness necrosis is present, exploration and resection are necessary. If only mucosal ischemia is present, it is possible to avoid resection by optimizing hemodynamics, antibi- otic administration, and close observation . Laboratory studies reveal that the patient is acidotic, with a blood pH of 7.14 and a WBC count of 25,000/mm 3 . You decide that there may be necrotic bowel and that abdominal exploration is warranted. ◆ ◆ Resection of the colon back to well-perfused edges is necessary. If the patient is stable and conditions are favorable, reanastomosis of the colon may be appropriate. If not, a colostomy and Hartmann pouch operation (stapling the distal colon closed and placing back into the abdomen) are warranted (Fig. 8-8). SAMPLE Q: How should you manage the following operative situations? Case Variation 8.7.12. Necrosis of the left colon