Acute Mesenteric Ischemia Among Post-Cardiac Surgery Patients Presenting with Multiple Organ Failure.

BACKGROUND: Acute mesenteric ischemia is a rare but severe complication after cardiac surgery. However, AMI is likely to be more frequent in the subgroup of patients presenting with multiple organ failure after a cardiac surgery. The primary objective of this study was to identify AMI risk factors among patients requiring ICU admission after cardiac surgery.

METHODS: Retrospective observational study of all the patients requiring admission to two ICU in a large university hospital after a cardiac surgery procedure. AMI confirmation was based on abdominal CT scan, digestive endoscopy, laparotomy, or post-mortem examination. Univariate and multivariate analysis were done to compare pre and in ICU characteristics between patient with or without AMI.

RESULTS: Between 2007 and 2013, a cardiac surgery was performed in 4948 patients, of whom 320 patients (6%) required ICU admission for multiple organ failure. AMI was confirmed in 10% of the patients admitted to the ICU for multiple organ failure (33/320). The prognosis of these patients was extremely poor with 28-day and 90-day mortality rates of 64% and 83% respectively. Non occlusive mesenteric ischemia was the main mechanism, involved in 83% of the patients. Coronary artery bypass graft, need for blood transfusion during cardiopulmonary bypass, ASAT ≥ 100 UI/L and SAPS II ≥ 50 at ICU admission were independently associated with AMI. An AMI risk-score based upon these four risk factors was able to identify three classes of risk: low risk (< 1%), intermediate risk (9%), and high risk (29%).

CONCLUSION: AMI is a frequent condition among patients presenting with multiple organ failure after cardiac surgery, occurring in 10% of them. The prognosis of AMI is extremely poor. The main mechanism of AMI is non-occlusive mesenteric ischemia, occurring in about 80% of patients. Further progress should be performed on prevention and earlier diagnosis.