What is the principle of Cardiopulmonary Resuscitation (CPR)?

Principles of Cardiopulmonary Resuscitation (CPR)

CPR is a life-saving emergency procedure that optimizes circulation and oxygenation through chest compressions and rescue breathing, with chest compressions being the foundation of CPR for all victims regardless of age. 1

Core Components of CPR

Chest Compressions

• Rate: 100-120 compressions per minute 1, 2
• Depth: At least 2 inches (5 cm) for adults 2
• Position: Center of chest, mid-sternum 3
• Technique: Allow complete chest recoil between compressions 2
• Minimize interruptions: Keep pauses under 10 seconds 1

Ventilations

• For healthcare providers: 30 compressions to 2 breaths ratio 1
• With advanced airway: 1 breath every 6-8 seconds (8-10 breaths/minute) while compressions continue without pauses 1

Conceptual Framework of CPR

CPR works through two primary mechanisms:

1. Circulatory support: Chest compressions create artificial circulation to deliver oxygen to vital organs, particularly the heart and brain 1
2. Oxygenation: Rescue breathing provides oxygen to the blood 1

Chain of Survival

The CPR process fits within the broader "Chain of Survival" which includes:

• Immediate recognition and activation of emergency response
• Early CPR with emphasis on chest compressions
• Rapid defibrillation
• Effective advanced life support
• Integrated post-cardiac arrest care 1, 2

Different Approaches Based on Rescuer Type

Lay Rescuers (Untrained)

• Should at minimum provide chest compressions for victims of cardiac arrest 1
• Hands-Only CPR (compression-only) is recommended for untrained rescuers attending adult victims of sudden cardiac arrest 2
• After identifying cardiac arrest, a lone responder should activate emergency response first, then immediately begin CPR 1

Trained Rescuers and Healthcare Providers

• Should provide both chest compressions and ventilations 1
• Should check for a pulse but limit this check to no more than 10 seconds 1
• Should use AED as soon as available 1

Special Considerations

Adult vs. Pediatric Victims

• Most adult cardiac arrests are sudden and of cardiac origin, making chest compressions paramount 1
• Pediatric arrests are often asphyxial, making ventilations relatively more important 1

Witnessed vs. Unwitnessed Arrest

• For witnessed arrest with a shockable rhythm, early defibrillation is critical 1
• The victim's chance of survival decreases with increasing interval between arrest and defibrillation 1

Common Pitfalls to Avoid

• Inadequate compression depth: Ensure compressions are at least 2 inches deep for adults 2
• Excessive interruptions: Minimize pauses in chest compressions 2
• Improper hand placement: Center hands on the sternum 3
• Leaning on the chest: Allow complete chest recoil between compressions 2
• Excessive ventilation: Avoid providing too many or too forceful breaths 2
• Delayed defibrillation: Use AED as soon as it becomes available 1, 2

Effectiveness of CPR

When performed correctly, high-quality CPR can significantly improve survival rates. Survival approaches 50% in EMS-treated patients after witnessed out-of-hospital ventricular fibrillation arrest when all links in the Chain of Survival are implemented effectively 2.

By understanding and correctly applying these principles, rescuers can provide the best chance of survival with good neurological outcomes for victims of cardiac arrest.