Evaluation of the abdomen in the critically ill patient: opening the black box

Evaluation of the abdomen in critically ill patients can be challenging. This article reviews the available data and proposes evidence-based guidelines for evaluation of the abdomen in the critically ill patient.

The critically ill are often clinically unevaluable due to distracting injuries, respiratory failure, obtundation, or other conditions. Even when patients can be examined, the clinical exam can be unreliable and misleading. Critically ill patients who are sufficiently stable to undergo imaging benefit from computerized tomography unless biliary sepsis is suspected, when ultrasound is preferred. There is an important role for endoscopy and angiography in the setting of gastrointestinal hemorrhage, as well as magnetic resonance imaging for mesenteric ischemia. Critically ill patients who are too unstable for imaging may require bedside laparoscopy or diagnostic peritoneal lavage. Abdominal compartment syndrome should be considered in the differential diagnosis of the unstable critically ill patient. Empiric laparotomy may still need to be employed in diagnosis and management of unstable patients.

Timely and accurate diagnosis of life-threatening intraabdominal pathology is essential to care for critically ill patients. A multitude of laboratory, radiologic, and interventional modalities are available to evaluate the abdomen in the critically ill.