Generalized skin mottling: an early sign of acute mesenteric infarction after cardiac surgery.

To the Editor: Acute mesenteric infarction after cardiac surgery is uncommon (0.1%-0.3%) but associated with a very high mortality rate (60%-90%).1-3 Early diagnosis is of critical importance in patients with mesenteric infarction because the only chance of cure is prompt surgical intervention.4 However, critically ill patients after cardiac surgery are often ventilated and sedated, and, therefore, signs and symptoms of abdominal pathology are masked. The difficulty in making the diagnosis of mesenteric infarction after cardiac surgery contributes heavily to its catastrophic mortality. We are reporting the cases of 2 cardiac surgery patients who presented generalized skin mottling as an early clinical sign of postoperative acute mesenteric infarction. The first patient was a 73-year-old man with a medical history of heavy smoking, hyperlipidemia, and cerebral vascular disease. He had an uneventful triple-vessel revascularization with extracorporeal circulation and was transferred to our intensive care unit under deep sedation and mechanical ventilation. On admission, the patient had generalized skin mottling characterized by unevenly distributed colored areas of different shades all over the lower limbs, the abdomen, and the thorax. Physical examination was negative. Hemodynamic parameters, urine output, arterial and mixed venous blood gases, standard bicarbonate, and lactate were within normal limits. After tracheal extubation at the 8th postoperative hour, the patient complained of abdominal pain progressively associated with oliguria and metabolic acidosis. The diagnosis of mesenteric ischemia was confirmed by an abdominal computed tomography scan and colonoscopy showing ischemic changes in the colon. An emergency laparotomy showed diffuse necrosis of the large intestine. The patient had a total colon resection with end ileostomy but died on the 4th postoperative day as a result of multiple-organ failure. The second patient was an 84-year-old man with a medical history of chronic renal failure and diabetes who had an uneventful mitral and aortic valves replacement. He presented in the immediate postoperative period with generalized skin mottling with no other clinical, hemodynamic, or metabolic disorder. After extubation, on day 1, the patient showed peritonitis signs associated with dramatic increases in leukocyte count, arterial lactate, and serum amylase. An exploratory laparotomy revealed massive necrosis of the small and large intestine. The patient had a subtotal bowel resection with stoma. He died on the 11th postoperative day as a result of sepsis. In critically ill patients, skin mottling is a clinical sign of vasoconstriction and tissue hypoperfusion. Mottling was reported as one of the presenting symptoms in 46% of patients from a general population undergoing surgery for mesenteric infarction.5 It is caused by the release of vasoactive products from the ischemic intestinal mucosa. These cases show that generalized skin mottling might be an early sign of mesenteric infarction in ventilated and sedated patients after cardiac surgery. It appeared several hours before abdominal clinical signs, hemodynamic deterioration, and metabolic acidosis. We conclude that mesenteric infarction should be suspected in sedated patients with generalized skin mottling after cardiac surgery. Patients presenting with this clinical sign should be woken up rapidly so that abdominal symptoms can be accurately evaluated and further diagnostic investigations undertaken.