What are the 2025 Basic Life Support (BLS) Advanced Cardiovascular Life Support (ACLS) guidelines for cardiopulmonary resuscitation (CPR) in adults?

2025 BLS/ACLS Guidelines for Adult Cardiopulmonary Resuscitation

The 2025 American Heart Association guidelines maintain the core BLS/ACLS algorithms from 2020 with emphasis on high-quality chest compressions at 100-120/min and depth of at least 2 inches (5 cm), immediate defibrillation for shockable rhythms, and epinephrine 1 mg IV/IO every 3-5 minutes for all cardiac arrest rhythms. 1, 2

Initial Recognition and Response

When you encounter an unresponsive patient, simultaneously check for absent or gasping respirations while palpating for a pulse—if no pulse is definitively felt within 10 seconds, immediately start CPR. 3, 2

• Shout for nearby help and activate the emergency response system via mobile device 2
• Send someone to retrieve an AED and emergency equipment immediately 2
• Agonal gasps are common in cardiac arrest and should NOT be mistaken for normal breathing 3

Basic Life Support Algorithm

Perform cycles of 30 chest compressions followed by 2 breaths until an advanced airway is placed. 2, 3

High-Quality CPR Technique:

• Push hard: at least 2 inches (5 cm) depth 2, 3
• Push fast: 100-120 compressions per minute 2, 3
• Allow complete chest recoil between compressions 2, 3
• Minimize interruptions in compressions—any pause reduces perfusion pressure 3
• Change compressor every 2 minutes or sooner if fatigued 2, 4
• Avoid excessive ventilation 2

Special Pulse Check Scenarios:

• If pulse present but no normal breathing: Provide rescue breathing at 1 breath every 6 seconds (10 breaths/min), check pulse every 2 minutes 2
• If possible opioid overdose with pulse: Administer naloxone per protocol while providing rescue breathing 2

Defibrillation Protocol

Use the AED as soon as it becomes available—for shockable rhythms (VF/pulseless VT), deliver one shock and immediately resume CPR for 2 minutes without checking pulse or rhythm. 2, 4, 3

Shock Energy:

• Biphasic defibrillator: 120-200 Joules (or manufacturer recommendation); if unknown, use maximum available 2, 3
• Monophasic defibrillator: 360 Joules 2, 3
• Second and subsequent doses should be equivalent or higher 2

Critical Timing:

• Check rhythm every 2 minutes after completing each 2-minute CPR cycle 4, 2
• Never check pulse or rhythm immediately after shock delivery—this wastes critical time when compressions should be ongoing 4
• Resume CPR immediately after shock, starting with chest compressions 2, 4
• Keep rhythm checks brief (less than 10 seconds) 4

Advanced Cardiovascular Life Support

Vascular Access and Medications:

Establish IV or IO access without interrupting compressions and administer epinephrine 1 mg IV/IO every 3-5 minutes throughout the resuscitation for all cardiac arrest rhythms. 2, 3, 5

For refractory VF/pulseless VT, administer antiarrhythmics: 2, 3

• Amiodarone: First dose 300 mg IV/IO bolus, second dose 150 mg 2
• Lidocaine (alternative): First dose 1-1.5 mg/kg, second dose 0.5-0.75 mg/kg 2

Advanced Airway Management:

Place an endotracheal tube or supraglottic airway device and confirm placement using waveform capnography or capnometry. 2, 3, 5

Once advanced airway is in place, provide 1 breath every 6 seconds (10 breaths/min) with continuous chest compressions—no pauses for ventilation. 2, 3

Continuous Monitoring:

Monitor CPR quality continuously using mechanical parameters (compression depth, rate) or physiologic parameters (end-tidal CO2, arterial pressure if available). 4

• If waveform capnography shows sudden sustained increase in PETCO2 (typically ≥40 mmHg), this indicates possible ROSC—perform immediate rhythm and pulse check even before the 2-minute interval 4, 3

Return of Spontaneous Circulation (ROSC)

Recognize ROSC by: 2, 3, 5

• Palpable pulse and measurable blood pressure 2, 5
• Abrupt sustained increase in PETCO2 ≥40 mmHg 2, 5
• Spontaneous arterial pressure waves on invasive monitoring 2, 5

When ROSC is achieved, immediately transition to post-cardiac arrest care. 3, 5

Reversible Causes (H's and T's)

Systematically evaluate and treat potential reversible causes throughout the resuscitation: 2, 5

• Hypovolemia: Administer IV fluids 5
• Hypoxia: Ensure adequate oxygenation 5
• Hydrogen ion (acidosis): Correct with adequate ventilation 5
• Hypo/hyperkalemia: Check and correct electrolytes 5
• Hypothermia: Rewarm if accidental hypothermia 5
• Tension pneumothorax: Perform needle decompression 5
• Tamponade (cardiac): Consider pericardiocentesis 5
• Toxins: Administer specific antidotes if available 5
• Thrombosis (pulmonary): Consider thrombolytics 5
• Thrombosis (coronary): Evaluate for acute coronary syndrome 5

Post-Cardiac Arrest Care

After achieving ROSC, secure the airway if not already done, maintain mean arterial pressure ≥65 mmHg with vasopressors as needed, and titrate oxygen to maintain saturation 92-98%. 5

• Obtain 12-lead ECG to identify ST-elevation myocardial infarction 5
• Consider urgent coronary angiography for suspected cardiac etiology 5
• Begin targeted temperature management for patients who do not follow commands 5
• Maintain normocapnia by monitoring with waveform capnography 5
• Avoid hyperventilation which decreases cerebral blood flow 5

Key Updates in 2025 Guidelines

The 2025 American Heart Association guidelines provide comprehensive recommendations for cardiac arrest management including new guidance on double sequential defibrillation, head-up CPR positioning, point-of-care ultrasound use, and refined termination of resuscitation rules based on EMS scope of practice. 1