INtestinal Failure, multiPle Organ Failure ANd CItrulline Assessment

The gastrointestinal dysfunction occurs frequently during the intensive care unit (ICU) stay and is associated with a worse prognosis. The gastrointestinal failure (GIF) is diagnosed based on symptoms such as bowel distension, ileus, diarrhea, digestive bleeding, or intestinal ischemia. A GIF score based on has been demonstrated to be correlated with outcome, with higher scores indicating higher risk of death. However, GIF may be occult or clinical signs can go undetected in critically ill patients due to the frequent use of analgesic, sedative or neuromuscular blocking agents, acute neurologic diseases, or delirium. Citrulline is a potential biomarker for small bowel function in critically ill patients with maintained renal function. Normal plasma citrulline levels (12-55 µmol/L) are determined by the balance between gut synthesis and kidney degradation. GIF is involved in the pathogenesis of multiple organ dysfunctions and failures (MOF) through various mechanisms, and it is often associated with high intra-abdominal pressure (IAP). IAP greater than 12 mmHg, may lead to abdominal compartment syndrome (ACS) and MOF, including cardiac, respiratory and kidney failure. Studies have suggested that GIF can be the consequence rather than the cause of MOF. The aim of this study is to investigate if plasma citrulline levels is associated with a clinical diagnosis of GIF, and may predict the development of MOF.