What is the initial clue suggesting hypovolemia as a cause of arrest?

• A. Severe chest pain
• B. Hyperthermia
• C. Low urine output
• D. Obvious blood loss

Answer: (D)

The key idea is that hypovolemia comes from a loss of circulating blood volume, so the most direct clue is evidence of actual blood loss. If there is obvious bleeding, it immediately points to reduced intravascular volume as the trigger for arrest, which in turn explains the poor perfusion leading to cardiac arrest in a child. The other options are less specific: severe chest pain isn’t typical in pediatric arrests, hyperthermia suggests fever or heat illness, and low urine output signals poor perfusion but doesn’t identify the cause as volume loss. When obvious blood loss is present, the priority is rapid restoration of intravascular volume with isotonic fluids and control of the bleeding.