What are the steps for cardiopulmonary resuscitation (CPR) in cardiac arrest situations?

Steps for Cardiopulmonary Resuscitation (CPR)

Immediately begin high-quality chest compressions at a rate of 100-120 per minute with a depth of at least 2 inches (5 cm), using a 30:2 compression-to-ventilation ratio, and apply an AED as soon as available while minimizing any interruptions in compressions. 1

Initial Recognition and Activation

• Check for responsiveness by tapping the victim's shoulder and shouting "Are you all right?" while simultaneously assessing for normal breathing (not just gasping). 1
• If the victim is unresponsive with no breathing or only gasping, assume cardiac arrest and immediately activate the emergency response system (call 911). 1
• Send someone to retrieve an AED if a second rescuer is available; if alone, activate emergency services first, then retrieve the AED if nearby before returning to start CPR. 1

High-Quality Chest Compressions

Compression technique is critical for survival:

• Position your hands on the lower half of the sternum (center of the chest) with arms fully extended and perpendicular to the patient's chest. 1, 2
• Push hard and fast with a depth of at least 2 inches (5 cm) but avoid exceeding 2.4 inches (6 cm). 1
• Maintain a rate of 100-120 compressions per minute—not faster, not slower. 1
• Allow complete chest recoil between compressions without leaning on the chest, as incomplete recoil reduces coronary perfusion. 1
• Minimize interruptions to less than 10 seconds—aim for a chest compression fraction of at least 60%. 1

Rescue Breathing (For Trained Rescuers)

• Deliver 2 breaths after every 30 compressions using a 30:2 ratio. 1
• Each breath should be delivered over 1 second with enough volume to produce visible chest rise. 1, 3
• Pause compressions for less than 10 seconds to deliver the 2 breaths. 1
• Avoid excessive ventilation, which increases intrathoracic pressure and decreases cardiac output. 3

Important caveat: If you are an untrained bystander or unwilling to provide mouth-to-mouth, perform compression-only CPR (hands-only CPR) continuously until help arrives—this is equally effective for sudden cardiac arrest. 1

AED Use and Defibrillation

• Turn on the AED immediately when it arrives and follow the voice prompts. 1
• Apply pads to bare chest (upper right chest and lower left side). 1
• Allow the AED to analyze rhythm without touching the patient. 1
• If a shock is advised, ensure everyone is clear, deliver the shock, then immediately resume chest compressions without checking pulse or rhythm. 1
• Continue CPR for 2 full minutes before the next rhythm check—do not interrupt compressions to check rhythm or pulse before this time. 1, 4

Critical pitfall: Never delay chest compressions to check for a pulse or rhythm immediately after shock delivery—this wastes precious perfusion time and worsens outcomes. 4, 5 Data show most patients remain pulseless for over 2 minutes after defibrillation, with 25% remaining pulseless beyond 120 seconds. 5

Compressor Rotation and Quality Maintenance

• Change compressors every 2 minutes (at the time of rhythm checks) or sooner if fatigued, as compression quality deteriorates rapidly with fatigue. 1, 4, 3
• The switch should occur in less than 5 seconds to minimize interruption. 2

Advanced Airway Management (Healthcare Providers)

Once an advanced airway (endotracheal tube or supraglottic device) is placed:

• Stop the 30:2 cycle and provide continuous chest compressions without pauses. 1
• Deliver 1 breath every 6 seconds (10 breaths per minute) while compressions continue uninterrupted. 1
• Confirm tube placement immediately with waveform capnography. 1, 3

Medication Administration (Healthcare Providers)

• Establish IV or IO access during CPR without interrupting compressions. 1, 3
• Administer epinephrine 1 mg IV/IO every 3-5 minutes for all cardiac arrest rhythms. 1, 3
• For refractory ventricular fibrillation/pulseless ventricular tachycardia, consider amiodarone 300 mg IV/IO bolus (or lidocaine 1-1.5 mg/kg as alternative). 1, 3

When to Stop CPR

Continue CPR until:

• Advanced life support providers arrive and take over. 1
• The victim starts to move or shows signs of life. 1
• Return of spontaneous circulation (ROSC) is confirmed by pulse, blood pressure, or sudden sustained increase in end-tidal CO₂ (typically ≥40 mmHg). 1
• You are too exhausted to continue and no one else can take over. 2
• A valid Do Not Attempt Resuscitation order is presented. 2

Key principle: The 2020 American Heart Association guidelines emphasize that survival depends on immediate recognition, early high-quality CPR, rapid defibrillation, and minimal interruptions in chest compressions. 1 Every second without compressions decreases survival, so the mantra is "push hard, push fast, minimize interruptions." 1, 6