In the majority of babies born with a slow heart rate, this will usually increase within the 30–60 seconds it takes to complete five effective inflation breaths and 30 seconds of effective ventilation breaths. It is therefore, logical to start compressions only if the heart rate remains less than 60 min-1 after this period of 30 seconds of effective ventilation. This hopefully clarifies previous confusion.
This change to the guidelines means that lung expansion and ventilation is established. There is more opportunity for the heart rate to respond which usually occurs within 30 seconds of effective ventilation and avoids the potential compromise of ventilation by compressions.
If the heart rate remains below 60 min-1 or absent after this period, synchronized compressions should be commenced at 3 compressions:1 ventilation before reassessing heart rate.
The heart rate should be reassessed every 30 seconds and once the heart rate exceeds 60 min-1 the compressions should be stopped.