Which of the following indicates the need for immediate medical assistance in an abdominal injury?

The indication for immediate medical assistance in the context of an abdominal injury is external bleeding. Abdominal injuries can often involve serious damage to internal organs or major blood vessels. When external bleeding is present, it suggests that there may be significant internal trauma that could lead to complications such as shock or severe blood loss.

Rapid loss of blood can lead to unconsciousness and can be life-threatening, emphasizing the need for urgent medical intervention. While nausea, thirst, and weakness can be symptoms associated with abdominal injuries, they do not necessarily indicate an acute emergency in the same way that visible external bleeding does. Thus, external bleeding serves as a critical warning sign that requires immediate action, prioritizing the patient's safety and wellbeing.