What are the initial steps and interventions for Advanced Cardiovascular Life Support (ACLS) in cardiac arrest management?

Advanced Cardiovascular Life Support (ACLS) in Cardiac Arrest Management

Immediately begin high-quality chest compressions at 100-120 compressions per minute with a depth of at least 2 inches (5 cm), activate the emergency response system, and obtain a defibrillator—these are the most critical initial interventions that directly impact survival. 1

Initial Recognition and Response Sequence

Check for responsiveness and pulse simultaneously within 10 seconds—if no definitive pulse is palpated, immediately start CPR without delay. 1, 2 Healthcare providers often take too long checking for pulses and have difficulty determining if one is present, leading to dangerous delays in compressions. 1

Immediate Actions (First 60 Seconds):

• Shout for nearby help and activate the emergency response system 1
• Send someone to retrieve the AED/defibrillator and emergency equipment immediately 1
• Attach cardiac monitor/defibrillator pads as soon as available to identify the arrest rhythm 2
• Begin chest compressions immediately—do not delay for any reason 1

High-Quality CPR: The Foundation of Resuscitation

CPR is the single-most important intervention for cardiac arrest, and chest compressions are the most critical component. 1 The quality of compressions directly determines coronary and cerebral perfusion, which are the best predictors of survival. 3

Compression Technique:

• Push hard: at least 2 inches (5 cm) depth 1, 2
• Push fast: 100-120 compressions per minute 1, 2
• Allow complete chest recoil between compressions 1
• Minimize interruptions—keep pauses under 10 seconds 1, 2
• Rotate compressors every 2 minutes to prevent fatigue 1

Ventilation Strategy:

• Before advanced airway: 30 compressions to 2 breaths 1, 2
• After advanced airway placement: continuous compressions with 1 breath every 6 seconds (10 breaths/minute) 1, 4, 2
• Avoid excessive ventilation—this increases intrathoracic pressure and decreases cardiac output 1, 4

Rhythm-Based Management

For Shockable Rhythms (VF/Pulseless VT):

Early defibrillation with concurrent high-quality CPR is critical to survival—for every minute in ventricular fibrillation, survival decreases dramatically. 1, 5

• Deliver one shock immediately when VF/pVT is identified 1, 2
• Use biphasic energy: 120-200 J per manufacturer recommendation (or 360 J for monophasic) 1, 2
• Resume CPR immediately after shock delivery without checking rhythm or pulse 1
• Continue CPR for 2 minutes before next rhythm check 1

For Non-Shockable Rhythms (Asystole/PEA):

• Resume CPR immediately for 2 minutes 1
• Focus on identifying and treating reversible causes (H's and T's) 1, 4
• Administer epinephrine as soon as IV/IO access is obtained 1

Pharmacological Interventions

Epinephrine:

Administration of epinephrine with concurrent high-quality CPR improves survival, particularly in patients with non-shockable rhythms. 1

• Dose: 1 mg IV/IO every 3-5 minutes throughout the arrest 1, 4, 2
• For shockable rhythms: give after 2nd shock 1
• For non-shockable rhythms: give as soon as IV/IO access is established 1
• Do not use high-dose epinephrine—it provides no benefit over standard dosing 4

Antiarrhythmics for Refractory VF/pVT:

For VF/pVT that persists after 2-3 shocks, administer amiodarone or lidocaine. 1, 2 Amiodarone improves rates of return of spontaneous circulation in refractory VF/pVT. 1

• Amiodarone: 300 mg IV/IO first dose, then 150 mg for second dose 1
• Lidocaine: alternative if amiodarone unavailable 1, 2

Advanced Airway Management

Consider advanced airway placement (endotracheal tube or supraglottic airway) without interrupting chest compressions. 2

• Confirm placement with waveform capnography—this is mandatory 1, 4, 2
• After placement: deliver 1 breath every 6 seconds with continuous compressions 1, 4, 2
• Do not hyperventilate—8-10 breaths per minute maximum 1

Monitoring CPR Quality

Use quantitative waveform capnography to monitor CPR effectiveness—target ETCO₂ >10 mmHg. 1, 2

• If ETCO₂ <10 mmHg: improve CPR quality (push harder, faster, minimize interruptions) 1
• Abrupt sustained increase in ETCO₂ (typically ≥40 mmHg) indicates return of spontaneous circulation 1, 4
• Do not use ETCO₂ cutoff values alone to terminate resuscitation efforts 1, 2

Reversible Causes: The H's and T's

Systematically evaluate and treat potential reversible causes during every resuscitation. 1, 4 Recognition that all cardiac arrests are not identical is critical for optimal outcomes. 1

The H's:

• Hypovolemia: Administer IV fluids 4
• Hypoxia: Ensure adequate oxygenation 4
• Hydrogen ion (acidosis): Correct with adequate ventilation 4
• Hypo/hyperkalemia: Check and correct electrolytes 4
• Hypothermia: Rewarm if accidental hypothermia 4

The T's:

• Tension pneumothorax: Needle decompression 4
• Tamponade (cardiac): Pericardiocentesis 4
• Toxins: Administer specific antidotes 4
• Thrombosis (pulmonary): Consider thrombolytics 4
• Thrombosis (coronary): Emergent cardiac catheterization 4

Post-Resuscitation Care (After ROSC)

Prompt initiation of targeted temperature management is necessary for all patients who do not follow commands after ROSC. 1

Immediate Post-ROSC Management:

• Confirm ROSC: Check pulse, blood pressure, and monitor for sustained ETCO₂ ≥40 mmHg 4
• Optimize oxygenation: Titrate oxygen to maintain SpO₂ 94-98% (avoid both hypoxia and hyperoxia) 4, 2
• Maintain normocapnia: Adjust ventilation to keep CO₂ in normal range 4
• Support hemodynamics: Use vasopressors to maintain adequate blood pressure 4
• Obtain 12-lead ECG: Identify ST-elevation myocardial infarction 4, 2
• Consider emergent coronary angiography for suspected cardiac etiology, especially with ST-elevation 4, 2

Temperature Management:

• Select and maintain constant target temperature between 32°C and 36°C 1
• Duration: at least 24 hours 1
• Prevent and treat fever after completion of targeted temperature management 1

Critical Pitfalls to Avoid

• Do not delay compressions to check for pulse beyond 10 seconds 1
• Do not interrupt compressions for rhythm checks more frequently than every 2 minutes 1
• Do not check pulse or rhythm immediately after defibrillation—resume CPR immediately 1
• Do not hyperventilate—this decreases cerebral blood flow and cardiac output 4, 2
• Do not use ETCO₂ alone to decide when to terminate resuscitation 1, 2
• Do not administer calcium, sodium bicarbonate, or high-dose epinephrine routinely—these are associated with worse outcomes 6

Special Circumstances

Pregnancy:

• Perform lateral uterine displacement to relieve aortocaval compression 2
• Consider perimortem cesarean delivery for women in cardiac arrest in the second half of pregnancy if ROSC not achieved within 4 minutes 1

Opioid Overdose:

• Administer naloxone if opioid overdose suspected, but continue standard ACLS 1
• High-quality CPR remains the mainstay of treatment 1

Refractory Cardiac Arrest:

• Consider ECPR (extracorporeal CPR) for select patients when conventional CPR is failing, particularly in witnessed arrests with shockable rhythms in settings where this can be implemented 1, 2