During CPR, an EtCO2 greater than what value suggests adequate compressions?

• A. 5 mmHg
• B. 10 mmHg
• C. 15 mmHg
• D. 20 mmHg

Answer: (B)

End-tidal CO2 monitoring during CPR is a real-time gauge of how well chest compressions are pushing blood through the body and delivering it to the lungs. The more effective the compressions, the more pulmonary blood flow you generate, and the more CO2 is carried to the lungs to be exhaled, increasing the EtCO2 reading. A value greater than 10 mmHg is used as a practical indicator that compressions are providing adequate perfusion. If EtCO2 stays below that level, perfusion is likely insufficient, so you’d focus on improving compression quality (depth and rate, minimizing pauses), ensuring a clear airway, and confirming ventilation is appropriate. A rising EtCO2 toward higher values can hint that circulation is improving or that ROSC may be occurring. This threshold is a guideline to assess CPR performance in real time, not an absolute guarantee of outcomes.