What are the updated 2025 Advanced Cardiovascular Life Support (ACLS) guidelines from the American Heart Association (AHA)?

2025 ACLS Updates: Key Changes from Previous Guidelines

The 2025 American Heart Association ACLS guidelines introduce several critical changes, most notably discontinuing routine calcium administration during cardiac arrest, expanding recommendations for extracorporeal CPR in select patients, and standardizing post-arrest temperature management for all patients who don't follow commands after return of spontaneous circulation. 1, 2

Major Changes in Medication Management

Calcium Administration - NEW

• Routine calcium administration during cardiac arrest is no longer recommended, representing a significant departure from previous practice patterns 2, 3
• This applies to all cardiac arrest patients unless specific indications exist (hyperkalemia, hypocalcemia, calcium channel blocker toxicity) 1

Vasopressor Protocol Updates

• Epinephrine remains the primary vasopressor at 1 mg IV/IO every 3-5 minutes during cardiac arrest 1, 2
• For nonshockable rhythms (asystole/PEA), administer epinephrine as soon as feasible after confirming cardiac arrest 1, 2
• For shockable rhythms (VF/pVT), epinephrine may be given after initial defibrillation attempts fail 1, 2
• High-dose epinephrine is not recommended for routine use (Class 3: No Benefit) 1
• Vasopressin alone or vasopressin plus methylprednisolone offers no advantage over epinephrine and may be considered but is not preferred 1

Post-Cardiac Arrest Care - MAJOR UPDATES

Temperature Management (Targeted Temperature Management)

• ALL adults who don't follow commands after ROSC should receive deliberate temperature control, regardless of arrest location (in-hospital vs. out-of-hospital) or initial rhythm (shockable vs. nonshockable) 1, 2, 3
• Maintain constant temperature between 32°C and 37.5°C during the post-arrest period 1, 2
• Patients with spontaneous hypothermia after ROSC should not be rewarmed faster than 0.5°C per hour if they don't follow commands 1, 2
• There is insufficient evidence to recommend specific temperatures for different patient subgroups 1, 3

Coronary Angiography Strategy - NEW

• Emergency coronary angiography is NOT recommended over delayed/selective strategies for post-ROSC patients unless they have: 2, 3
  • ST-elevation MI on ECG
  • Cardiogenic shock
  • Electrical instability
  • Signs of significant myocardial damage
  • Ongoing ischemia
• This represents a more conservative, selective approach compared to previous recommendations

Extracorporeal CPR (ECPR) - EXPANDED INDICATION

• ECPR is now considered reasonable (Class 2a) for select patients with cardiac arrest refractory to standard ACLS when provided within an appropriately trained and equipped system of care 1, 2, 3
• This requires institutional protocols, trained teams, and rapid deployment capability 1
• Implementation should begin early in patients not responding to conventional therapies 1

Seizure Management - NEW RECOMMENDATION

• A therapeutic trial of a nonsedating antiseizure medication may be reasonable for adult cardiac arrest survivors with EEG patterns on the ictal-interictal continuum 1, 2, 3
• This addresses the challenging gray zone between clear seizures and background EEG patterns 1

CPR Quality Emphasis - REINFORCED STANDARDS

Compression Parameters

• Depth: At least 2 inches (5 cm) but not exceeding 2.4 inches (6 cm) 2, 4, 3
• Rate: 100-120 compressions per minute 2, 4, 3
• Allow complete chest recoil between compressions 2, 4
• Minimize interruptions - maximize chest compression fraction 2, 3
• Rotate compressors every 2 minutes to prevent fatigue 2

Monitoring CPR Quality

• Use quantitative waveform capnography (target PETCO2 >10 mmHg) when available 2
• Consider arterial pressure monitoring during CPR when feasible 2

Advanced Airway Management

• Once advanced airway placed: provide 1 breath every 6 seconds (10 breaths/min) with continuous chest compressions 2, 4
• Use waveform capnography to confirm and monitor advanced airway placement 2
• Avoid excessive ventilation - this is detrimental to outcomes 2
• Before advanced airway: maintain 30:2 compression-to-ventilation ratio 4

Defibrillation Protocol

• Single-shock strategy remains standard (not stacked shocks) 2
• Resume chest compressions immediately after shock delivery 4
• For refractory VF/pVT, consider amiodarone (300 mg first dose, 150 mg second dose) or lidocaine (1-1.5 mg/kg first dose, 0.5-0.75 mg/kg second dose) 2

Oxygen Management

• Use maximal inspired oxygen (100%) during CPR 2, 3
• After ROSC, target oxygen saturation 94-98% or PaO2 75-100 mmHg once arterial values can be measured 3
• Avoid both hypoxemia and hyperoxemia in post-arrest care 3

Systems of Care - NEW EMPHASIS

• Organ donation is now formally recognized as an important outcome to consider in cardiac arrest systems of care development and evaluation 1, 2, 3
• This represents acknowledgment that not all resuscitation attempts will result in neurologically intact survival, but organs may save other lives 1

Diversity, Equity, and Inclusion - NEW SECTION

• The 2025 guidelines formally introduce diversity, equity, and inclusion considerations into the guideline document 1
• Acknowledges lack of diverse representation in cardiac arrest research and calls for improved methods to include participants from diverse backgrounds 3

Critical Pitfalls to Avoid

• Do NOT routinely administer calcium during cardiac arrest unless specific indications exist 2, 3
• Do NOT perform emergency coronary angiography on all post-ROSC patients - use selective strategy based on clinical presentation 2, 3
• Do NOT delay chest compressions to check for pulse in suspected cardiac arrest 2, 4
• Do NOT interrupt chest compressions unnecessarily during resuscitation 2, 4
• Do NOT misinterpret agonal gasping as normal breathing - this is a common cause of failure to recognize cardiac arrest 2, 4
• Do NOT use high-dose epinephrine routinely 1
• Do NOT rewarm spontaneously hypothermic post-arrest patients faster than 0.5°C per hour if they don't follow commands 1, 2

Special Populations

Pregnant Patients

• Perform lateral uterine displacement to relieve aortocaval compression during resuscitation 2

Opioid Overdose

• Focus on CPR first - naloxone administration should not delay high-quality CPR 3
• After ROSC with naloxone, observe in healthcare setting until risk of recurrent toxicity is low 3

Drowning Victims

• Emphasize rescue breathing along with chest compressions due to hypoxic nature of drowning arrest 3
• Trained rescuers should provide ventilations as part of CPR 3

Drug Administration Routes

• IV access should be established first when possible for medication administration 3
• IO access is appropriate if IV attempts unsuccessful (Class 2a, LOE B-NR) 3