At what point is a victim considered clinically dead?

A victim is considered clinically dead when there is a complete cessation of breathing and circulation. This definition is grounded in the basic principles of life support; the heart and lungs must function to deliver oxygenated blood throughout the body and to maintain vital organ function. Without breathing, oxygen cannot enter the body, and without circulation, the blood cannot transport oxygen to the tissues. The combination of these two essential functions stopping signifies that the body's systems are no longer sustaining life, leading to a clinical determination of death.

The other options do not provide accurate indicators for clinical death. For example, a heart rate below 60 bpm does not necessarily equate to clinical death, as individuals can live with bradycardia under certain conditions. A lack of response is a critical sign of an unconscious state but does not confirm the absence of circulation or breathing. Similarly, a drastic drop in blood pressure may indicate a medical emergency but does not directly mean that breathing and circulation have stopped, which are necessary for the determination of clinical death. The core understanding lies in recognizing the vital roles that breathing and circulation play in sustaining life.