What Happens During CPR? A Comprehensive Guide

Cardiopulmonary resuscitation (CPR) is a crucial emergency procedure that combines chest compressions with rescue breaths to restore blood flow and oxygen delivery when a person’s heart has stopped beating (cardiac arrest) or breathing has ceased. Without immediate intervention, cardiac arrest can lead to irreversible brain damage or death within minutes. CPR buys valuable time until professional medical help arrives, significantly improving survival rates. Proper CPR training is essential for saving lives and navigating high-pressure emergency situations.

This comprehensive guide, based on the principles recognized by MyCPR NOW, provides a step-by-step breakdown of what happens during CPR, the techniques involved, and the reasons behind each action.

Understanding Cardiac Arrest

What is Cardiac Arrest?

Cardiac arrest is a sudden and often unexpected loss of heart function, leading to a cessation of blood flow to the brain and other vital organs. This critical condition occurs when the heart’s electrical system malfunctions, causing the heart to stop beating effectively. Without prompt medical intervention, cardiac arrest can result in death within minutes. Immediate actions, such as performing CPR, are crucial to maintaining blood flow and oxygen delivery until professional medical help arrives.

Causes and Symptoms

Cardiac arrest can stem from a variety of causes, which are generally categorized into primary and secondary factors:

• Primary Causes: These are heart-related issues, such as coronary artery disease, heart failure, and arrhythmias (irregular heartbeats). These conditions can disrupt the heart’s electrical activity, leading to cardiac arrest.

• Secondary Causes: These include non-heart-related factors like drowning, electrocution, severe trauma, and drug overdose. These situations can also trigger cardiac arrest by affecting the heart’s ability to function properly.

Recognizing the symptoms of cardiac arrest is vital for timely intervention. Common signs include:

• Sudden Collapse: The person may suddenly fall to the ground without warning.

• Loss of Consciousness: The individual will be unresponsive and unable to communicate.

• Absence of Breathing or Pulse: The person will not be breathing normally (or at all) and will have no detectable pulse.

Understanding these causes and symptoms can help you act quickly and effectively in an emergency.

Recognition and Assessment: The First Critical Step

Quickly recognizing when someone requires CPR is vital because every second without oxygen-rich blood reaching the brain increases the chance of permanent damage. Delayed action can drastically reduce survival rates.

It is crucial to continue performing CPR until emergency medical services arrive or the person shows signs of life.

How to Recognize Cardiac Arrest and the Need for CPR:

• Assess Responsiveness:

• Gently shake or tap the person while calling out loudly, “Are you okay?”

• Look for any movement, reaction, or signs of awareness.

• Check for Normal Breathing:

• Observe the chest for 5–10 seconds to see if it rises and falls.

• Occasional gasping, known as agonal breathing, is not normal breathing and requires immediate CPR. Minimize any interruptions and if you need to call for help, pause for only a few seconds to ensure continuous chest compressions.

• Activate Emergency Medical Services (EMS):

• Call 911 immediately or direct someone nearby to do so.

• If an Automated External Defibrillator (AED) is available, send someone to retrieve it.

Key Consideration:

• If you’re unsure whether the person needs CPR, begin CPR. It’s better to act unnecessarily than to delay critical life-saving measures.

Preparing to Perform CPR

Essential Preparations:

Before you begin performing CPR, it’s crucial to prepare yourself and the scene properly. Here are the key steps to ensure you’re ready to act:

1. Call Emergency Medical Services: Dial 911 or your local emergency number immediately to alert professional medical help. Time is of the essence in a cardiac arrest situation.

2. Check the Scene: Ensure the area is safe for both you and the person in need. Remove any potential hazards that could interfere with the CPR process.

3. Check the Person: Verify that the person is unresponsive and not breathing. Gently shake or tap them while calling out loudly to see if they respond.

4. Position the Person: Place the individual on their back on a firm, flat surface. This positioning is essential for effective chest compressions.

5. Start CPR: Begin chest compressions and, if trained, provide rescue breaths. Follow the established CPR process to maintain blood flow and oxygen delivery.

6. Use an Automated External Defibrillator (AED): If an AED is available, use it as soon as possible. Follow the device’s instructions to analyze the person’s heart rhythm and deliver a shock if necessary.

7. Continue CPR: Keep performing CPR until emergency medical services arrive, the person shows signs of life, or you are physically unable to continue. Persistence is key to increasing the chances of survival.

By following these essential preparations, you can help ensure a successful CPR process and significantly improve the chances of survival for someone experiencing cardiac arrest.

Chest Compressions: The Heart of CPR

Chest compressions are the single most important component of CPR. They manually pump blood through the heart and deliver oxygen to vital organs, mimicking the heart’s natural function.

How to Perform High-Quality Chest Compressions:

• Positioning Matters:

  • Lay the person flat on a firm surface, such as the floor.

  • Kneel beside their chest to ensure effective leverage.

• Proper Hand Placement:

  • Place the heel of one hand on the center of the chest, between the nipples.

  • Place the other hand on top, interlocking your fingers.

  • Avoid pressing on the ribs or the bottom of the sternum.

• Technique:

  • Keep your arms straight and lock your elbows.

  • Position your shoulders directly above your hands for maximum force.

  • Use your body weight to press down firmly and quickly.

• Depth and Rate:

  • Compress the chest to a depth of at least 2 inches (5–6 cm) in adults.

  • Perform compressions at a rate of 100–120 beats per minute.

• Recoil Between Compressions:

  • Allow the chest to return to its normal position after each compression. Full recoil ensures proper blood flow.

Why Chest Compressions Work:

By compressing the chest, you’re forcing the heart to push blood to the brain and other vital organs. This maintains oxygen delivery, which is critical for preventing brain damage and organ failure.

Rescue Breaths: Delivering Life-Saving Oxygen

Rescue breaths are the second essential component of CPR. They provide oxygen to the lungs, which is then circulated by chest compressions.

Steps to Perform Rescue Breaths:

1. Open the Airway:

   • Tilt the person’s head back slightly by placing one hand on their forehead and the other under their chin.

   • Lift the chin to ensure the airway is open.

   • Look for visible obstructions and remove them, if present.

2. Seal and Deliver the Breath:

   • Pinch the person’s nose shut with your thumb and index finger.

   • Take a deep breath and place your mouth over theirs, creating an airtight seal.

   • Blow into their mouth for 1 second, watching for the chest to visibly rise.

3. Repeat:

   • Deliver a second breath after the chest deflates.

   • Each set of rescue breaths follows 30 chest compressions.

Hands-Only CPR: An Alternative for Untrained Responders

For bystanders untrained in rescue breaths, performing continuous chest compressions (hands-only CPR) is still highly effective and recommended until professional help arrives.

Compression-to-Ventilation Ratio: Ensuring Balance

The ratio of chest compressions to rescue breaths is designed to maximize oxygen delivery and blood circulation.

Standard Compression-to-Ventilation Ratios:

• Single Rescuer: 30 compressions followed by 2 rescue breaths (30:2).

• Two-Rescuer CPR: Alternating 30 compressions with 2 breaths, ensuring minimal interruptions in compressions.

Why Ratios Matter:

Maintaining the correct ratio ensures oxygenated blood is effectively circulated to the brain and heart. Interruptions in compressions reduce the efficacy of CPR and must be minimized.

Using an Automated External Defibrillator (AED)

An AED can restore a normal heart rhythm in cases of sudden cardiac arrest caused by abnormal electrical activity in the heart. AEDs are designed to be simple and intuitive, with clear instructions.

Steps to Use an AED:

1. Turn On the AED: Follow the device’s audio or visual prompts.

2. Apply the Pads:

   • Expose the person’s chest and remove any moisture.

   • Attach the pads as indicated (one above the right chest, the other on the left side).

3. Ensure Safety:

   • Clear the area to ensure no one is touching the person during the AED’s analysis or shock delivery.

4. Deliver the Shock: If advised, press the shock button.

5. Resume CPR: Perform chest compressions immediately after the shock is delivered, as advised by the AED.

Importance of Early Defibrillation:

Using an AED within the first few minutes of cardiac arrest can significantly increase survival rates, especially when combined with high-quality CPR.

Continuation of CPR: Persistence Saves Lives

CPR is a physically demanding process, but maintaining effort is critical.

When to Stop CPR:

• Signs of Recovery: The person begins breathing, moving, or showing other signs of life. Additionally, stop performing CPR if the person shows visible signs of life or if there are safety concerns.

• Professional Help Arrives: Emergency medical personnel take over.

• Physical Exhaustion: If you can no longer continue and no one is available to assist, stop CPR and wait for help.

Transfer of Care: Handoff to Medical Personnel

When emergency responders arrive, they will take over and provide advanced life support. Your role is to provide a concise summary of what happened, including:

• The duration of CPR.

• The number of compression cycles performed.

• Whether an AED was used and if a shock was delivered.

• Details of the initial collapse or injury.

Clear communication helps ensure seamless continuity of care.

Conclusion

CPR is a life-saving skill that empowers individuals to intervene effectively in emergencies. By sustaining blood flow and oxygen delivery to the brain and vital organs, CPR buys critical time until professional medical help arrives.

Key Takeaways:

• Immediate Recognition: Act quickly when someone is unresponsive or not breathing.

• High-Quality Chest Compressions: Focus on depth, rate, and full recoil.

• Rescue Breaths: If trained, combine compressions with breaths for maximum effectiveness.

• AED Use: Employ an AED as soon as it’s available.

• Persistence: Continue CPR until professional help takes over or the person recovers.

MyCPR NOW emphasizes the importance of CPR certification and training for everyone. Knowing CPR can make the difference between life and death, whether for a loved one, a coworker, or a stranger. Stay prepared—your actions could save a life.