Cardiopulmonary resuscitation (CPR) is the intervention used when a person experiences cardiac arrest (the heart suddenly stops beating). While prompt action is necessary, the quality of chest compressions delivered is a major factor in determining survival and neurological outcomes. High-quality CPR ensures temporary, artificial circulation of blood to the brain and heart muscle, keeping these organs viable until the heart can be restarted. The Chest Compression Fraction (CCF) is a specific metric used to measure the effectiveness and continuity of this life-saving effort.
Defining the Goal of Chest Compression Fraction
Chest Compression Fraction (CCF) is defined as the total time spent actively performing chest compressions divided by the total time of the resuscitation attempt, expressed as a percentage. This calculation directly measures the continuity of blood flow generated by the rescuer. For example, if a ten-minute resuscitation includes two minutes of pauses, the CCF is 80%.
Maintaining a high CCF is important because it directly relates to coronary perfusion pressure, which drives blood flow to the heart muscle. Blood flow to the heart and brain ceases the moment compressions stop, and it takes several compressions to rebuild that pressure once they resume. Current guidelines recommend a CCF of at least 60%. However, high-performance teams often aim for 80% or more to maximize the chance of a successful outcome by minimizing interruptions.
Techniques for Minimizing Pauses
The most significant threat to a high CCF is the pauses required for other medical interventions. One common source of interruption is defibrillation, where an electrical shock is delivered to reset the heart rhythm. To minimize hands-off time, the defibrillator should be charged while chest compressions are still being performed.
Compressions should stop only for the brief moment required to clear the patient and deliver the shock, aiming for a “peri-shock” pause of less than ten seconds. Compressions must be restarted immediately once the shock is delivered, or if the rhythm is not shockable.
A second source of pauses occurs during ventilation, especially when following the traditional 30 compressions to 2 breaths ratio. Rescuers should deliver the two breaths quickly and efficiently, ensuring the total pause for ventilation does not exceed ten seconds.
In advanced settings where a tube has been placed in the patient’s airway, compressions can be delivered continuously without interruption for breaths. This allows for asynchronous ventilation, which is a major advantage for maintaining a high CCF.
Brief interruptions are also required for rhythm and pulse checks, which are mandated at regular two-minute intervals during CPR. These assessments must be limited to a maximum duration of ten seconds to prevent a prolonged cessation of blood flow.
The Role of Team Coordination in Sustained Compressions
Achieving a consistently high CCF requires structured team organization. Rescuer fatigue is a primary concern, as it can compromise the quality of compressions (rate and depth) in as little as two minutes. To mitigate this, compressors must be rotated regularly every two minutes, or approximately every five cycles of the 30:2 ratio.
This rotation should occur seamlessly during one of the necessary pauses, such as the two-minute rhythm check. The incoming rescuer should be ready to take over immediately, ensuring the transition is completed in just a few seconds. Clear and defined roles for every team member are necessary for successful coordination.
Assigning specific responsibilities, such as a compressor, a ventilating person, a team leader, and a timekeeper, streamlines the entire resuscitation process. This structure ensures that tasks like preparing medication or placing monitoring devices do not distract the primary compressor, preventing unnecessary interruptions. The team leader coordinates the switch and ensures all tasks are accomplished without compromising compression continuity.
Using Feedback Technology to Maintain Quality
Technology provides objective measurement and real-time guidance, which is indispensable for maintaining high-quality compressions and a high CCF. Devices such as automated external defibrillators or dedicated monitors contain sensors that measure the rate and depth of compressions. This allows the rescuer to receive immediate, audible, or visual feedback, which can be used to correct technique on the spot.
This real-time data helps rescuers ensure they are pushing at the recommended rate of 100 to 120 compressions per minute and achieving a depth of 5 to 6 centimeters for an adult. Beyond immediate guidance, these devices also record the entire resuscitation attempt, allowing teams to review the data later. Post-event analysis includes a precise calculation of the CCF, which is used in training to identify where interruptions occurred, leading to continuous performance improvement.