Understanding the Phases of CPR

Cardiopulmonary resuscitation (CPR) is one of the most important life-saving skills anyone can learn. It is designed to maintain blood circulation and oxygenation in individuals who are experiencing cardiac arrest until professional medical help arrives. Cardiac arrest, which occurs when the heart suddenly stops beating effectively, can lead to death within minutes if untreated. CPR provides a manual method of pumping blood to the brain and vital organs, thereby increasing the chances of survival. This guide provides an in-depth explanation of the phases of CPR and emphasizes the importance of each step in the process within the broader context of emergency cardiac care.

Phase 1: Recognition of Cardiac Arrest

Recognizing the signs of cardiac arrest is the crucial first step in CPR. Delays in identifying a cardiac emergency can reduce the likelihood of survival, so it is important to act quickly. Bystander cardiopulmonary resuscitation significantly improves survival rates by ensuring immediate action is taken before professional help arrives.

Key Steps in Recognizing Cardiac Arrest

1. Assess Responsiveness:

• Approach the individual quickly and calmly. Gently tap or shake their shoulder while loudly asking, “Are you okay?” or “Can you hear me?”

• If the person does not respond, this indicates a loss of consciousness, which is often a sign of a severe medical condition such as cardiac arrest, and immediate action is required.

2. Check for Breathing:

• Look for chest movements to determine if the person is breathing normally.

• Listen by placing your ear near their mouth to hear any breath sounds.

• Feel for airflow by placing your hand near their nose and mouth.

• This process should take no longer than 10 seconds. If the person is not breathing or only gasping (agonal breathing), it’s a sign of cardiac arrest, and you need to proceed with CPR immediately.

• Identify the initially identified cardiac rhythm: Recognizing the initially identified cardiac rhythm is crucial as it impacts the subsequent CPR steps and potential survival outcomes.

3. Call for Help:

• Call 911 or your local emergency number immediately. If there are others nearby, instruct someone else to make the call while you begin CPR.

• When calling, provide clear details about the situation, including the person’s condition, location, and any actions you are taking.

• Many dispatchers will guide you through CPR, providing instructions while help is on the way.

4. Position the Person:

• Ensure the person is lying flat on their back on a firm surface. If they are on a bed or soft surface, carefully move them to the ground to perform CPR effectively.

Phase 2: Chest Compressions

Chest compressions are the most critical element of CPR, especially during the circulatory phase. When the heart stops beating effectively, chest compressions manually pump blood to the brain and other vital organs. Without compressions, the organs will begin to suffer irreversible damage due to a lack of oxygen.

How to Perform Effective Chest Compressions

1. Position Your Hands:

• Kneel beside the person’s chest. Place the heel of one hand on the center of their chest, just below the nipple line, on the lower half of the breastbone (sternum).

• Place your other hand on top of the first and interlock your fingers. Your elbows should remain straight, and your shoulders should be directly above your hands to maximize force.

2. Compression Depth and Technique:

• Depth: For adults and children, compress the chest at least 2 inches (5 cm) but no more than 2.4 inches (6 cm). For infants, use two fingers and compress about 1.5 inches (4 cm).

• Force: Use your body weight, not just your arms, to press down on the chest. This ensures that compressions are deep enough to effectively circulate blood.

• Recoil: Allow the chest to fully recoil between compressions. Full recoil allows the heart to refill with blood between each compression, which is critical for effective circulation.

• Ventricular Fibrillation: In cases of ventricular fibrillation, effective chest compressions are crucial as they help maintain blood flow until defibrillation can be performed.

3. Compression Rate:

• The ideal rate for chest compressions is 100-120 compressions per minute. 

• Consistency is crucial. If compressions are too slow, blood flow will not be adequate. If they are too fast, the heart may not have enough time to fill between compressions, reducing the effectiveness.

4. Minimize Interruptions:

• Once compressions have begun, they should not be interrupted unless absolutely necessary (e.g., giving rescue breaths, using an AED). Continuous compressions are key to maintaining blood flow.

5. Fatigue Management:

• Performing chest compressions is physically demanding. If there is another person trained in CPR available, switch every 2 minutes to ensure that compressions remain effective. The switch should be seamless and quick to avoid any delay in compressions.

Phase 3: Rescue Breaths (If Trained)

Rescue breaths are crucial when providing oxygen to someone who is not breathing or not breathing adequately. They are particularly important in cases of drowning, drug overdoses, or other situations where breathing is compromised. If you are trained and comfortable, rescue breaths should be administered along with chest compressions. During the metabolic phase of CPR, which starts after 17 minutes, rescue breaths become even more critical as this phase is characterized by severe cerebral cell death and impending myocardial necrosis, marking the last opportunity for effective resuscitation efforts.

How to Perform Rescue Breaths

1. Open the Airway:

• After 30 chest compressions, tilt the person’s head back slightly to open the airway. Place one hand on their forehead and use the other hand to lift their chin. This maneuver helps prevent the tongue from obstructing the airway.

2. Seal the Airway:

• Pinch the person’s nose shut to prevent air from escaping, then create a seal around their mouth by covering it completely with your own.

• If performing CPR on an infant, place your mouth over both their nose and mouth to create an airtight seal.

3. Give Two Breaths:

• Deliver two rescue breaths, each lasting about 1 second. Watch for the chest to rise as you give each breath, which indicates the air is entering the lungs. If the chest does not rise, reposition the head and try again.

• According to emergency cardiovascular care science guidelines, effective rescue breaths are crucial for oxygenating the blood during CPR.

• Caution: Do not over-inflate the lungs by blowing too forcefully. Over-inflation can cause air to enter the stomach, leading to vomiting, which complicates the CPR process.

4. Continue with Compressions:

• After the two rescue breaths, immediately resume chest compressions. Continue alternating 30 chest compressions with 2 rescue breaths until help arrives or the person begins to breathe on their own.

Phase 4: Use of an Automated External Defibrillator (AED)

An Automated External Defibrillator (AED) is a device that analyzes the heart’s rhythm and delivers a shock if necessary to restore a normal rhythm. AEDs are easy to use and provide clear voice prompts, making them accessible to both trained and untrained rescuers. Early use of an AED can greatly improve the chance of survival in cardiac arrest cases. In cases of hospital cardiac arrest, the effectiveness of AEDs is particularly notable, as rapid defibrillation significantly enhances survival rates.

How to Use an AED

1. Turn on the AED:

• Turn on the AED as soon as it’s available. The device will provide voice prompts or visual instructions to guide you through the process.

• Emergency medical services (EMS) often provide AEDs and play a crucial role in supporting resuscitation efforts during out-of-hospital cardiac arrests (OHCA).

2. Attach the Pads:

• Expose the person’s chest and attach the AED pads as shown in the diagrams on the pads. One pad should be placed on the upper right side of the chest, and the other on the lower left side, below the armpit.

• Ensure the pads are applied firmly to bare skin to ensure proper contact.

3. Stand Clear:

• Ensure that no one is touching the person while the AED analyzes the heart’s rhythm. Say “Stand clear” out loud to make sure everyone is aware.

4. Deliver the Shock:

• If the AED advises a shock, make sure no one is touching the person and press the shock button when prompted. Some AEDs may deliver the shock automatically.

5. Resume CPR:

• After the shock is delivered, immediately resume chest compressions. Even if the shock restores the heart’s rhythm, chest compressions should continue to ensure adequate circulation until professional medical help arrives.

6. Follow AED Prompts:

• The AED will continue to monitor the person’s heart and will prompt you if another shock is needed or if you should continue with CPR.

Phase 5: Continued CPR and Monitoring

Once you have begun CPR, it is crucial to continue until one of the following occurs:

1. The person shows signs of life (e.g., breathing normally, moving, or regaining consciousness).

2. Professional help arrives and takes over.

3. You are physically unable to continue due to exhaustion.

4. The AED instructs you to stop or no further shocks are advised.

Emergency medical service personnel will take over CPR and provide advanced care, including timely interventions such as the collapse-to-shock interval.

Monitoring the Person’s Condition

1. Signs of Life:

• If the person begins to breathe normally, move, or regain consciousness, stop CPR but continue to monitor their condition closely. Place them in the recovery position (on their side) to keep their airway clear.

2. Professional Help:

• When emergency responders arrive, give them as much information as possible. Tell them when CPR began, how many shocks were delivered by the AED, and any other relevant details.

• EMS personnel performed CPR in accordance with guidelines, ensuring immediate care before hospital transport.

3. Fatigue:

• CPR is physically exhausting, especially the chest compressions. If there is more than one trained rescuer, switch roles every 2 minutes to avoid fatigue and maintain effective compressions.

Conclusion: Mastering the Phases of CPR

Understanding and mastering the phases of CPR are essential for anyone who might be called upon to respond in a cardiac emergency. Every second counts in these situations, and knowing how to recognize cardiac arrest, perform high-quality chest compressions, give rescue breaths if needed, and use an AED can significantly increase a person’s chances of survival.

Regular CPR training and certification ensure that you are equipped with the knowledge and skills to act confidently and effectively during emergencies. By following the detailed steps outlined above, you can be prepared to make a life-saving difference when it matters most. Additionally, staying informed about cardiac arrest and cardiopulmonary resuscitation outcome reports emphasizes the importance of standardized data collection and outcome evaluation following resuscitation efforts.