Point-of-care gastrointestinal and urinary tract sonography in daily evaluation of gastrointestinal dysfunction in critically ill patients (GUTS Protocol)

There is currently a lack of universally accepted criteria for gastrointestinal (GI) failure or dysfunction in critical care. Moreover, the clinical assessment of intestinal function is notoriously difficult and thus often goes unrecognized, contributing to poor outcomes. A recent grading system has been proposed to define acute gastrointestinal injury (AGI) in conjunction with other organ function scores (e.g., SOFA). Ultrasonography has become widely accepted as a diagnostic tool for GI problems and pathology. We propose a sonographic examination of the abdomen, using the GUTS protocol (gastrointestinal and urinary tract sonography) in critically ill patients as part of the point-of-care ultrasound evaluation in patients with AGI. This article reviews possible applications of ultrasonography that may be relevant to monitor the GI function in critically ill patients. The GI ultrasound protocol (GUTS) focuses on four gastrointestinal endpoints: gastrointestinal diameter, mucosal thickness, peristalsis, and blood flow. Moreover, it is possible to examine the urinary tract and kidney function. Real-time ultrasound with the GUTS protocol is a simple, inexpensive, bedside imaging technique that can provide anatomical and functional information of the GI tract. Further studies are needed to investigate the utility of GUTS with other parameters, such as GI biomarkers, AGI class, and clinical outcomes.