You find an infant who is unresponsive, is not breathing, and does not have a pulse. What action should you take next?

When an infant is found unresponsive, not breathing, and without a pulse, the most critical action is to start CPR immediately. This is because high-quality CPR can maintain blood flow to the vital organs, especially the brain and heart, until professional help arrives. In pediatric emergencies, the initial moments are vital, and providing CPR for about 2 minutes helps ensure that oxygen-rich blood is circulated, potentially reversing the cardiac arrest.

After initiating CPR for a short period, it's essential to activate the emergency response system. By doing this, additional help is on the way, which is crucial for the long-term survival of the infant.

The other actions, while important in different contexts, would delay critical lifesaving measures. For instance, if emergency response is called first, precious time would be lost, during which CPR could have been initiated. Checking for breathing and pulse for an extended period also adds unnecessary delay. Using an AED immediately is also not appropriate in infants unless no other option is available, as the pads and settings are specifically designed for older children and adults.

Thus, the correct response in this life-threatening situation is to begin CPR promptly before activating emergency services.