Chest compression fraction (CCF) in PALS is the percentage of total resuscitation time spent actively delivering chest compressions. The American Heart Association lists a CCF greater than 80% as a component of high-quality CPR. In practical terms, if a pediatric resuscitation lasts 10 minutes, compressions should be ongoing for at least 8 of those minutes.
How CCF Is Calculated
The formula is straightforward: divide the total time compressions are being performed by the total duration of the resuscitation, then multiply by 100 to get a percentage. If you deliver compressions for 14 out of 18 minutes, your CCF is about 78%. Every second you pause, whether for a rhythm check, a pulse check, or switching rescuers, pulls that number down.
The AHA Target and What It Means
The AHA’s high-quality CPR metrics for both pediatric and adult resuscitation set the same CCF target: greater than 80%. This sits alongside other quality markers like adequate compression depth, a rate of 100 to 120 compressions per minute, full chest recoil between compressions, and avoiding excessive ventilation.
That said, the 80% threshold is more of a performance benchmark than a proven survival cutoff in children. The AHA’s own pediatric basic life support guidelines note that while CCF values of 70% to 90% are achievable in most resuscitations, there is not enough data to confirm that hitting a specific CCF number directly improves pediatric outcomes. A 2024 study published in Circulation found that CCF alone was not significantly associated with survival to hospital discharge or return of spontaneous circulation in pediatric in-hospital cardiac arrests. What the study did find, however, was that longer individual pauses in compressions were associated with worse survival. So the length of each interruption may matter more than the overall percentage.
Why Pauses Happen and How to Limit Them
During a pediatric code, compressions get interrupted for specific clinical reasons. The most common include rhythm checks (recommended roughly every 2 minutes), pulse checks, defibrillation, airway management, and switching the person doing compressions. Each of these eats into your CCF, and the seconds add up fast.
AHA guidelines specify that pauses in chest compressions should be less than 10 seconds for any single interruption. That applies to rhythm checks, pulse checks, and the moments immediately before and after a defibrillation shock (called peri-shock pauses). When a shockable rhythm like ventricular fibrillation is identified, the recommendation is to deliver a single shock and then resume compressions immediately, starting with compressions rather than rechecking the rhythm right away.
A few practical strategies help keep CCF high:
- Pre-charge the defibrillator during compressions so the shock can be delivered the moment you pause, minimizing the peri-shock gap.
- Swap compressors during rhythm checks rather than taking a separate pause for the switch. Fatigue degrades compression quality within about two minutes, so combining the swap with a scheduled rhythm check avoids an extra interruption.
- Assign roles clearly so the team knows who is checking the rhythm, who is preparing medications, and who is next on compressions. Confusion during a code creates unnecessary pauses.
How an Advanced Airway Changes the Approach
Before an advanced airway is placed, PALS uses a compression-to-ventilation ratio (15:2 with two rescuers), which means compressions pause briefly for breaths. Once an endotracheal tube or supraglottic airway is in place, compressions become continuous. One rescuer compresses without stopping while another delivers a breath roughly every 2 to 3 seconds. This shift eliminates the pauses for ventilation and can push CCF significantly higher. One study cited in the 2025 AHA guidelines found that CCF values of 90% to 100% were associated with markers of high-quality CPR in pediatric patients with an advanced airway.
How CCF Is Monitored in Real Time
Modern defibrillators and CPR feedback devices can track CCF automatically. Accelerometer-based pads placed on the patient’s chest detect when compressions are occurring and calculate the fraction in real time, displaying it on the monitor. Some systems also provide audio or visual prompts when compressions have been paused too long. After the event, many devices generate a post-resuscitation report that includes CCF alongside compression rate and depth, giving teams concrete data for debriefing and quality improvement.
For PALS certification purposes, the key takeaway is that CCF greater than 80% is the benchmark, achieved by keeping every pause under 10 seconds and minimizing the number of interruptions overall. The underlying principle is simple: the heart cannot circulate blood when no one is pushing on it, and every second without compressions lets coronary and cerebral perfusion pressure drop. Getting compressions restarted quickly is one of the most impactful things a resuscitation team can control.