What does waveform capnography monitor during CPR?

Waveform capnography primarily monitors end-tidal CO2 levels during CPR. This measurement provides critical insights into the effectiveness of chest compressions and the overall status of the patient's ventilation. During resuscitation, it allows healthcare providers to gauge the perfusion of the lungs and the body, as CO2 levels in exhaled air reflect metabolic processes and how well carbon dioxide is being cleared from the body.

A significant aspect of capnography during CPR is that it can indicate whether chest compressions are effective. Properly performed compressions will result in higher levels of end-tidal CO2, as they facilitate blood flow to the lungs and subsequently to the heart. If the end-tidal CO2 reading remains low despite ongoing compressions, it may suggest poor circulation and necessitate a change in CPR technique or reevaluation of the patient's condition.

In contrast, monitoring heart rate, the depth of chest compressions, or blood pressure does not provide the same real-time feedback about the effectiveness of CPR in terms of ventilation and circulation dynamics. Therefore, the ability of waveform capnography to reflect end-tidal CO2 levels makes it an essential tool during CPR.