What are the steps of Advanced Cardiovascular Life Support (ACLS) for an adult patient with no specified medical history experiencing cardiac arrest?

ACLS Steps for Adult Cardiac Arrest

The core steps of ACLS follow a systematic approach centered on high-quality CPR, early defibrillation for shockable rhythms, appropriate medication administration, and advanced airway management, with all interventions organized around minimizing interruptions in chest compressions. 1

Immediate Recognition and Activation

• Simultaneously activate the emergency response system and initiate CPR immediately upon recognizing cardiac arrest 1
• Assess for pulse and responsiveness within 10 seconds; if no definite pulse is felt, begin CPR immediately 1
• Attach defibrillator/monitor pads as soon as available to identify the cardiac rhythm 1

High-Quality CPR Foundation

All ACLS interventions are built upon the foundation of high-quality CPR, which is more critical to survival than any other single intervention 1

• Push hard (at least 2 inches/5 cm depth) and fast (at least 100-120 compressions per minute) 1
• Allow complete chest recoil after each compression 1
• Minimize interruptions in compressions to less than 10 seconds 1
• Rotate compressors every 2 minutes to prevent fatigue 2
• Use a compression-to-ventilation ratio of 30:2 until an advanced airway is placed 1
• After advanced airway placement, deliver continuous compressions at 100-120/min with 8-10 breaths per minute (one breath every 6-8 seconds) 1

Rhythm Identification and Management

For Shockable Rhythms (VF/Pulseless VT):

• Defibrillate immediately with minimal interruption in compressions 1
• Use biphasic 120-200J (per manufacturer recommendation) or monophasic 360J 3
• Resume CPR immediately after shock delivery for 2 minutes before checking rhythm 1
• Administer epinephrine 1 mg IV/IO every 3-5 minutes during resuscitation 1
• For shock-refractory VF/pVT (after 2-3 unsuccessful shocks), administer antiarrhythmic: 1
  • Amiodarone 300 mg IV/IO bolus (second dose 150 mg), OR
  • Lidocaine 1-1.5 mg/kg IV/IO (second dose 0.5-0.75 mg/kg) 3, 2
• Continue CPR-shock-drug cycles every 2 minutes 1

For Non-Shockable Rhythms (PEA/Asystole):

• Administer epinephrine 1 mg IV/IO as soon as possible and repeat every 3-5 minutes 1
• Continue high-quality CPR with rhythm checks every 2 minutes 1
• Aggressively search for and treat reversible causes (H's and T's) 1

Airway Management

• Initially provide ventilation with bag-mask device (30:2 ratio with compressions) 1
• Consider advanced airway (endotracheal tube or supraglottic device) when appropriate, but do not interrupt compressions for prolonged periods during placement 1
• Confirm advanced airway placement with waveform capnography 2
• After advanced airway placement, switch to continuous compressions with 8-10 breaths per minute 1
• Avoid excessive ventilation, which can impair venous return and worsen outcomes 1

Vascular Access and Medications

• Establish IV or intraosseous (IO) access for medication administration 2
• Epinephrine 1 mg IV/IO every 3-5 minutes improves survival, particularly in non-shockable rhythms 1
• Antiarrhythmics (amiodarone or lidocaine) for refractory VF/pVT after initial defibrillation attempts 3, 2

Physiologic Monitoring During CPR

• Use quantitative waveform capnography (ETCO2) to monitor CPR quality; ETCO2 <10 mmHg suggests inadequate compressions 2
• If available, monitor intra-arterial pressure during compressions (target relaxation phase pressure >20 mmHg) 2
• A sudden increase in ETCO2 may indicate return of spontaneous circulation (ROSC) 1

Search for Reversible Causes

Systematically evaluate and treat the H's and T's throughout resuscitation: 1

• H's: Hypovolemia, Hypoxia, Hydrogen ion (acidosis), Hypo/Hyperkalemia, Hypothermia
• T's: Tension pneumothorax, Tamponade (cardiac), Toxins, Thrombosis (pulmonary), Thrombosis (coronary)

Post-ROSC Care

Once ROSC is achieved, immediately transition to post-cardiac arrest care: 1

• Maintain mean arterial pressure ≥65 mmHg with vasopressors 3
• Target SpO2 92-98% to avoid both hypoxia and hyperoxemia 3
• Obtain 12-lead ECG and consider emergent coronary angiography if indicated 3
• Initiate targeted temperature management for all patients who do not follow commands after ROSC 1, 3
• Provide comprehensive post-cardiac arrest care including neuroprognostication 1

Critical Pitfalls to Avoid

• Never delay defibrillation for medication preparation in VF/pVT 2
• Avoid prolonged pulse checks; limit to 10 seconds maximum 1, 3
• Do not hyperventilate patients, especially after advanced airway placement 1
• Minimize all interruptions in chest compressions, including during rhythm checks and advanced airway placement 1
• Do not base treatment decisions solely on rhythm interpretation; consider the entire clinical picture 1

Special Considerations

• Recognize that not all cardiac arrests are identical; specialized management may be necessary for specific conditions (pregnancy, post-cardiac surgery, electrolyte abnormalities, opioid overdose) 1
• Consider extracorporeal CPR (ECPR) for select refractory cardiac arrest patients when conventional CPR is failing and appropriate systems are in place 3, 2