Cardiopulmonary Resuscitation (CPR) is an emergency procedure performed when the heart stops beating, requiring immediate, high-quality chest compressions to circulate blood to the brain and vital organs. The effectiveness of CPR depends on maintaining the correct compression depth and rate with minimal interruption. Performing compressions is physically demanding, and even trained rescuers quickly experience fatigue, causing compression quality to degrade significantly. This decline reduces the patient’s chance of survival, making the timely rotation of rescuers a necessary component of the resuscitation effort. A pre-planned switch ensures that high-quality CPR continues until advanced medical help arrives.
The Standard Interval for Rescuer Rotation
The internationally recognized standard for switching chest compression rescuers is approximately every two minutes, or after five cycles of compressions and ventilations in a standard 30:2 ratio. This timing is based on physiological studies showing that rescuer fatigue often begins around the two-minute mark, making it difficult to maintain compression quality.
Compression depth, which should be at least two inches (five centimeters) for an adult, often decays noticeably after 90 seconds. The target rate of 100 to 120 compressions per minute must be consistently maintained throughout this period.
The two-minute interval is often coordinated with other protocol breaks, such as rhythm checks on an automated external defibrillator (AED). Aligning the switch with these pauses minimizes the overall hands-off time. The non-compressing rescuer tracks time and prepares the incoming rescuer for the transition. The purpose of this fixed rotation is to proactively prevent the drop in quality that occurs when a rescuer becomes tired.
Recognizing Signs of Compression Fatigue
A switch must happen immediately if compression quality drops, regardless of the fixed interval. The non-compressing rescuer, or monitor, observes the compressor for signs of fatigue to ensure effective chest compressions continue.
A decrease in compression depth is the most common sign of fatigue. Compressions may become shallow, failing to reach the minimum two-inch requirement, which reduces blood flow. Other signs include a slowing of the rate below 100 per minute, or an increase in rate paired with shallow depth.
A visible sign of fatigue is the rescuer leaning on the patient’s chest between compressions. This leaning prevents the chest wall from fully recoiling, which is necessary for the heart to refill with blood. The monitor must call for an immediate switch upon observing any decline, prioritizing quality over the time interval.
Maintaining High-Quality Compression During the Switch
The transition between rescuers is a critical moment because any pause interrupts blood flow. The primary goal is to minimize “hands-off time”—the duration between the last compression by the outgoing rescuer and the first by the incoming rescuer. This pause must be kept under 10 seconds, and ideally, under five seconds.
A smooth transition requires clear verbal communication. The incoming rescuer must be positioned and ready to take over immediately as the outgoing rescuer concludes their final compression. The outgoing rescuer moves out of the way to allow the new rescuer to rapidly move into position.
The new compressor must quickly confirm correct hand placement over the breastbone before initiating compressions without delay. They should immediately begin compressions at the correct rate and depth, ensuring continuity of blood circulation. Frequent training is necessary to achieve a seamless handoff.