What are the recommended steps for Advanced Cardiac Life Support (ACLS) in cardiac arrest?

Advanced Cardiac Life Support (ACLS) Protocol

Immediately initiate high-quality CPR with chest compressions at 100-120/min, depth at least 2 inches (5 cm), while simultaneously checking rhythm and preparing for defibrillation if indicated—this forms the foundation of all ACLS interventions. 1

Initial Assessment and CPR Quality

Start CPR immediately upon recognizing cardiac arrest, performing cycles of 30 compressions and 2 breaths until advanced providers arrive or an AED becomes available. 1

Critical CPR Quality Metrics:

• Compression rate: 100-120 per minute 1
• Compression depth: At least 2 inches (5 cm) 1
• Allow complete chest recoil between compressions 1
• Minimize interruptions in compressions 1
• Avoid excessive ventilation 1
• Change compressor every 2 minutes or sooner if fatigued 1

Rhythm-Based Management Algorithm

For VF/Pulseless VT (Shockable Rhythms):

Deliver one shock immediately, then resume CPR for 2 minutes before rechecking rhythm. 1

Defibrillation Energy:

• Biphasic: 120-200 Joules initially (manufacturer recommendation); if unknown, use maximum available. Subsequent doses should be equivalent or higher. 1
• Monophasic: 360 Joules 1

Drug Therapy for Refractory VF/pVT:

• Epinephrine 1 mg IV/IO every 3-5 minutes throughout resuscitation 1
• Amiodarone: First dose 300 mg bolus, second dose 150 mg 1
• Lidocaine (alternative): First dose 1-1.5 mg/kg, second dose 0.5-0.75 mg/kg 1

Important caveat: While amiodarone and lidocaine improve survival to hospital admission, they do NOT improve overall survival to discharge or neurological outcomes in most patients. However, they DO significantly improve survival to discharge in bystander-witnessed arrests, suggesting time-dependent benefit. 1

For Asystole/PEA (Non-Shockable Rhythms):

Continue high-quality CPR for 2-minute cycles while administering epinephrine and aggressively searching for reversible causes. 1

• Epinephrine 1 mg IV/IO every 3-5 minutes 1
• Do NOT routinely administer sodium bicarbonate—evidence suggests it may worsen survival and neurological recovery in undifferentiated cardiac arrest 1

Vascular Access and Airway Management

IV/IO Access:

Establish IV or IO access as soon as feasible to administer medications. 1

Advanced Airway:

• Endotracheal intubation or supraglottic airway 1
• Use waveform capnography or capnometry to confirm and continuously monitor ET tube placement 1
• Once advanced airway is placed: Give 1 breath every 6 seconds (10 breaths/min) with continuous chest compressions—do NOT pause compressions for ventilation 1

Reversible Causes (H's and T's)

Systematically evaluate and treat reversible causes during resuscitation: 1

The H's:

• Hypovolemia 1
• Hypoxia 1
• Hydrogen ion (acidosis) 1
• Hypo-/hyperkalemia 1
• Hypothermia 1

The T's:

• Tension pneumothorax 1
• Tamponade, cardiac 1
• Toxins 1
• Thrombosis, pulmonary 1
• Thrombosis, coronary 1

Return of Spontaneous Circulation (ROSC)

Recognize ROSC by: 1

• Palpable pulse and measurable blood pressure 1
• Abrupt sustained increase in PETCO₂ (typically ≥40 mmHg) 1
• Spontaneous arterial pressure waves with intra-arterial monitoring 1

Upon achieving ROSC, immediately transition to post-cardiac arrest care. 1

Extracorporeal CPR (ECPR)

ECPR is reasonable for select patients with cardiac arrest refractory to standard ACLS when provided within an appropriately trained and equipped system. 1 The 2024 AHA focused update upgraded this recommendation based on the ARREST trial, which demonstrated significantly improved survival to discharge and 6-month survival for patients with refractory cardiac arrest and shockable rhythms receiving ECPR. 1

Key Requirements for ECPR:

• Highly trained team 1
• Specialized equipment 1
• Multidisciplinary support within healthcare system 1
• Select patients with potentially reversible pathogenesis 1

Common Pitfalls to Avoid

Do NOT routinely use magnesium—RCTs have not found it improves return of circulation, survival, or neurological outcome regardless of presenting rhythm. Exception: torsades de pointes. 1

Do NOT routinely use sodium bicarbonate—it may worsen outcomes in undifferentiated cardiac arrest. Reserve for special circumstances like hyperkalemia and drug overdose. 1

Do NOT delay CPR to troubleshoot equipment or establish access—immediate high-quality compressions are paramount. 1

Do NOT provide excessive ventilation—this increases intrathoracic pressure and decreases venous return, worsening outcomes. 1