A patient suffered blunt trauma to the abdomen and is undergoing diagnostic peritoneal lavage. Which finding in the aspirate would be considered abnormal?

In the context of a diagnostic peritoneal lavage after blunt abdominal trauma, the presence of stool and urine in the aspirate is considered abnormal. The purpose of the diagnostic peritoneal lavage is to evaluate for internal injuries or bleeding within the peritoneal cavity by examining the fluid obtained.

The presence of stool indicates a potential injury to the gastrointestinal tract, warranting immediate medical intervention, as this could lead to contamination of the peritoneal cavity and subsequent peritonitis. Similarly, the presence of urine suggests a possible injury to the urinary system, which is a serious concern. These findings would prompt further diagnostic imaging and possible surgical intervention, as they indicate significant underlying injuries.

In contrast, less than 500 red blood cells and fewer than 500 white blood cells in the aspirate may still be within a range considered acceptable for blunt trauma, as some minor bleeding can occur without indicating major injury. Clear fluid with no cells suggests no acute bleeding or infection, which is a reassuring finding. Trace amounts of red and white blood cells can also indicate minor trauma, which might not necessitate surgical intervention. Thus, stool and urine presence clearly indicates abnormal findings that would require immediate attention.