What gradual change may suggest CPR fatigue?

A fall in EtCO2, or end-tidal carbon dioxide, is an important indicator during the assessment of a patient receiving cardiopulmonary resuscitation (CPR). EtCO2 levels reflect the effectiveness of chest compressions and the overall circulation to the lungs. Typically, during effective CPR, you would expect to see EtCO2 levels remain stable or even increase if the compressions are adequately perfusing the heart and lungs.

When CPR fatigue begins to set in, the quality of chest compressions may decrease, which can lead to inadequate ventilation and perfusion. This decline will usually result in lower EtCO2 readings, indicating that CO2 is not being adequately expelled during exhalation due to poor blood flow and inadequate chest wall movement. Therefore, a significant drop in EtCO2 can signal that the CPR provider is becoming fatigued or that the quality of compressions is diminishing, which could lead to reduced chances of resuscitation success.

This explanation highlights how monitoring EtCO2 can help identify a potential issue during CPR, allowing the code team to recognize when a change in provider or a break might be necessary to maintain the effectiveness of the resuscitation effort.