The FAST exam is primarily used to detect free intraperitoneal or pericardial fluid in trauma patients, serving as a rapid, bedside assessment tool. While organ injuries may be suspected, the FAST exam is not primarily designed to assess for solid organ lacerations.

According to AIUM and ACEP guidelines:

“The primary goal of the FAST exam is to detect the presence of free fluid suggestive of hemorrhage in trauma patients.”