BLS Study Guide 2026

Immediately after delivering a shock with an AED, the rescuer should resume chest compressions without delay. There should be no pause to check for a pulse or rhythm, as early resumption of compressions is critical to maintain blood flow to the brain and heart. The AED will re-analyze the rhythm after two minutes of CPR.

In emergency situations involving an adult patient who is unconscious, unresponsive, or otherwise unable to give explicit consent, healthcare providers operate under the principle of implied consent. It is assumed that the patient would consent to life-saving treatment if they were able to communicate. This allows for immediate, critical care without delay.

Emergency medical providers can provide treatment without explicit consent when a person is unconscious or unresponsive, based on the principle of implied consent. In such critical situations, it is presumed that the person would want to receive life-saving care. This allows for immediate intervention to preserve life and prevent further harm.

Gasping (agonal breathing) combined with unresponsiveness are key indicators of cardiac arrest, signaling that the person's heart has stopped or is failing, and they are not breathing effectively. Immediate initiation of BLS, including chest compressions, is necessary in this critical situation. Recognizing these signs promptly is vital for patient survival.

During AED analysis, the device is detecting the victim's heart rhythm to determine if a shock is needed. Any movement or contact from a rescuer can create electrical interference, which the AED might misinterpret as a heart rhythm or an artifact. This interference can lead to an inaccurate analysis, potentially delaying a life-saving shock or causing the AED to advise against a necessary one.

Drowning is an asphyxia-driven arrest; AHA recommends starting with rescue breaths to address hypoxia as the underlying cause.