Case Details

Cardiology General Medicine

Indian Doctors Network posted a case

over 1 year ago

ABDOMINAL PAIN AND METABOLIC ACIDOSIS

Courtesy: 100 cases in surgery

History
A 65-year-old man presents to the emergency department with an 8 h history of severe generalized abdominal pain. Earlier in the day he passed fresh blood mixed in with his stool.His past medical history includes diabetes, hypertension and atrial fibrillation. He is not currently taking any anticoagulation therapy for his atrial fibrillation. He smokes 20 cigarettes
per day.

Examination
He has difficulty lying still on the bed. He has a temperature of 37.5°C with an irregularly irregular pulse of 110/min. His blood pressure is 90/50mmHg. Abdominal examination shows generalized tenderness with absent bowel sounds. Rectal examination confirms loose stool mixed with some fresh blood.

Questions
• What does the arterial blood gas show?
• What is the most likely diagnosis?
• What are the differential diagnoses?
• What other investigations can you suggest?
• What is the treatment and prognosis for this condition?

ANSWER
The arterial blood gas shows a metabolic acidosis (low pH, negative base excess and high lactate) with partial respiratory compensation (low pCO2). The most likely diagnosis is mesenteric ischaemia secondary to superior mesenteric artery thrombosis or embolism.
Atrial fibrillation is a risk factor for embolism.

Differential Diagnosis
• Pancreatitis
• Ruptured abdominal aortic aneurysm
• Perforated viscus

Investigation should include:
• routine bloods and serum amylase to exclude pancreatitis
• electrocardiogram
• chest X-ray: may show free air under the diaphragm
• abdominal X-ray: typically ‘gasless’
• computerized tomography of the abdomen: not always diagnostic with ischaemic bowel but would help to exclude an abdominal aortic aneurysm.

The prognosis associated with this condition is poor, with less than 20 per cent survival.The patient should be resuscitated with intravenous fluids and broad-spectrum antibiotics given. The patient should then be taken for urgent laparotomy where any dead bowel isresected. Revascularization by embolectomy or bypass may improve doubtfully viable bowel
and allow primary anastamosis. Otherwise, both ends of the bowel should be exteriorized.

KEY POINTS
• Atrial fibrillation increases the risk of arterial embolization.
• A re-look laparotomy at 24 h may be required to check for further intestinal ischaemia.



Feed Profile Image