Chest compressions are the central element of cardiopulmonary resuscitation (CPR), designed to manually circulate blood and oxygen to the brain and heart during cardiac arrest. Rescuer fatigue, the physical exhaustion experienced during continuous resuscitation efforts, poses a serious threat to the effectiveness of this life-saving technique. When a rescuer becomes tired, the quality of compressions declines rapidly, directly impacting the patient’s chance of survival. This physical decline often sets in within the first two minutes of compression delivery.
Impact on Compression Depth
The most significant effect of rescuer fatigue is a substantial reduction in chest compression depth. Effective compressions require pushing the adult chest down at least 2 inches (5 cm), but not exceeding 2.4 inches (6 cm). As the rescuer’s arm and shoulder muscles tire, the force they can generate decreases, causing the compressions to become shallower. Compressions that do not reach the minimum depth fail to generate adequate pressure, meaning less blood is pumped out of the heart to the brain and other organs. Studies have shown that this decline in depth can become noticeable as early as 90 seconds into continuous CPR.
Changes to Compression Rate and Chest Recoil
Rescuer fatigue compromises the mechanics of the compression cycle, affecting both rate and chest recoil. The ideal compression rate is between 100 and 120 compressions per minute; a rate outside this optimal range compromises the efficiency of blood circulation. The failure to allow full chest recoil is another serious consequence of fatigue. Full recoil requires the rescuer to lift their weight completely off the chest wall, allowing the chest to spring back to its normal position. When a rescuer leans on the chest due to exhaustion, incomplete recoil prevents the heart from fully refilling with blood, severely limiting the volume available for the next compression.
Strategies for Maintaining High-Quality Compressions
Rescuer Rotation
The most effective strategy to combat rescuer fatigue is the preemptive rotation of rescuers. Current guidelines recommend switching the person performing chest compressions every two minutes, or sooner if signs of fatigue are evident. This two-minute interval aligns with the time frame in which compression quality often begins to decline. A coordinated, rapid switch minimizes the interruption in compressions, which is essential because any pause severely limits blood flow to the patient.
Proper Body Mechanics
Proper body mechanics are foundational for delaying the onset of fatigue. A rescuer should position themselves with straight arms and their shoulders directly over the patient’s chest. This posture allows the rescuer to use their body weight, relying on larger core and back muscles rather than fatiguing smaller arm and shoulder muscles. Maintaining this mechanical advantage prolongs the time a rescuer can deliver effective compressions.
Real-Time Feedback Devices
The use of real-time audiovisual feedback devices provides a technological safeguard against the subtle decline caused by fatigue. These devices monitor the depth and rate of compressions, giving the rescuer immediate data to correct their technique. This objective feedback helps rescuers maintain performance standards, ensuring depth and rate remain within life-saving parameters throughout the resuscitation effort.