Which of the following is a criteria for evacuation in cases of abdominal complaint?

Blood in urine, feces, or vomit is a critical indicator for evacuation in cases of abdominal complaints. The presence of blood suggests potentially serious underlying conditions such as gastrointestinal bleeding, perforation, or other significant pathologies that require prompt medical evaluation and intervention. This could indicate life-threatening conditions that could rapidly worsen if not addressed, making evacuation a necessary step in ensuring the patient's safety and receiving appropriate medical care.

Severe abdominal pain, while concerning, can occur in many situations that may not require immediate evacuation if other criteria are not met. Persistent nausea, while uncomfortable and sometimes indicative of other problems, does not inherently suggest a life-threatening issue on its own. Localized swelling in the abdomen, while it could indicate a problem, does not show the same level of urgency or potential for life-threatening conditions as the presence of blood does. Thus, the presence of blood is a decisive factor in determining the need for immediate evacuation.