Review Question - QID 106074

The patient with sudden onset abdominal pain, atrial fibrillation, rectal blood and pneumoperitoneum on upright radiograph likely has acute mesenteric ischemia with bowel perforation. The most immediate next step in management is emergent laparotomy.

Signs and symptoms of acute mesenteric ischemia include extreme pain, vomiting, diarrhea, and heme positive stools. Additionally, patients often have risk factors for embolization including atrial fibrillation, heart disease, and hyperlipidemia. Patients are treated with a Fogarty catheter embolectomy as well as a resection of obviously necrotic intestine. A second look laparotomy is often performed 24-72 hours postoperatively to remove further necrotic bowel.

Cartwright et al. review the evaluation of acute abdominal pain in adults and note that location of pain is a useful starting point followed by associated symptoms. Symptoms in patients which suggest emergent surgical conditions include fever, protracted vomiting, syncope, and evidence of GI blood loss.

Klar et al review acute mesenteric ischemia as a vascular emergency and note that it is still fatal in 50-70% of cases. Rapid diagnosis (within 4-6 hours of onset) is vital to improving survival.

Figure A demonstrates an upright radiograph with pneumoperitoneum. Note the appearance of the lucent air between the liver and the diaphragm.

Illustration A is a gross depiction of necrotic areas of small intestine that can be seen in a patient with acute mesenteric ischemia.

Incorrect Answers:
Answer 1: Abdominal ultrasound may be appropriate if acute cholecystitis was suspected. However, this patient's sudden onset abdominal pain with atrial fibrillation, vascular risk factors, and pneumoperitoneum are more suggestive of perforation due to acute mesenteric ischemia.

Answer 2: Administration of heparin may be appropriate for some patients with acute mesenteric ischemia that do not require immediate operative intervention. However, this patient has clear evidence of bowel perforation and requires immediate operative intervention.

Answer 3: CT scan of the abdomen and pelvis with IV contrast would be appropriate for undifferentiated abdominal patient in a patient of this age. However, this patient with pneumoperitoneum requires emergent operative intervention.

Answer 5: Intravenous analgesia would be appropriate. However, observation alone would not be appropriate for this critically ill patient with a presentation suggestive of acute mesenteric ischemia.

Bullet Summary:
For patients with suspected acute mesenteric ischemia with associated pneumoperitoneum or signs of bowel perforation, the most appropriate immediate step in management is emergent laparotomy.