What does the term 'no-flow time' refer to in CPR?

• A. The time during which no chest compressions are being delivered (pauses).
• B. The interval between collapse and calling for help.
• C. The time from starting CPR to the first AED shock.
• D. The duration of chest compressions only.

Answer: (A)

No-flow time is the period during CPR when no chest compressions are being delivered. It matters because blood flow to the brain and heart largely depends on continuous compressions; any pause interrupts perfusion and can worsen outcomes. Pauses for ventilations or rhythm checks add to no-flow time, so the goal is to keep interruptions as brief as possible and resume compressions immediately after any pause. The other options describe times related to different CPR steps but do not define this interruption period.