What is the most accurate method for confirming cardiac arrest?

The most accurate method for confirming cardiac arrest is through ECG or waveform capnography. This approach provides direct and objective evidence of cardiac activity or the absence thereof. An ECG monitors the electrical activity of the heart and will clearly display if there is no heartbeat or electrical activity present, which confirms cardiac arrest.

Waveform capnography is also a valuable tool in this context; it measures the concentration of carbon dioxide in exhaled air, which decreases significantly during cardiac arrest as the lungs are no longer perfused. The absence of a capnogram or a flat waveform indicates that the heart is not pumping blood, further substantiating the diagnosis of cardiac arrest.

Using methods such as checking for a pulse, visual observation for movement, or listening for breath sounds is less reliable. A pulse check can be subject to error, especially if the pulse is weak or difficult to palpate. Similarly, visual observations can be misleading, and breath sounds may be present in some instances where cardiac arrest has occurred. Therefore, the use of ECG or waveform capnography offers a clear and definitive confirmation of cardiac arrest, making it the most accurate method.