What are the current CPR (Cardiopulmonary Resuscitation) and ACLS (Advanced Cardiovascular Life Support) guidelines for managing cardiac arrest?

Current CPR and ACLS Guidelines for Managing Cardiac Arrest

The 2020 American Heart Association guidelines for cardiopulmonary resuscitation (CPR) and advanced cardiovascular life support (ACLS) recommend high-quality chest compressions at a rate of 100-120 compressions per minute with a depth of at least 2 inches (5 cm), allowing complete chest recoil, and minimizing interruptions as the cornerstone of cardiac arrest management. 1

Initial Assessment and Basic Life Support (BLS)

Recognition and Response

1. Check for responsiveness
2. Shout for nearby help and activate emergency response system
3. Check for breathing (no breathing or only gasping) and pulse simultaneously (within 10 seconds)
4. If no pulse and not breathing normally, begin CPR immediately 1

High-Quality CPR Components

• Compression rate: 100-120/minute
• Compression depth: At least 2 inches (5 cm), but avoid exceeding 2.4 inches (6 cm)
• Chest recoil: Allow complete chest recoil after each compression
• Interruptions: Minimize interruptions in compressions (< 10 seconds)
• Compression-to-ventilation ratio: 30:2 (without advanced airway)
• Compressor rotation: Every 2 minutes or sooner if fatigued 1, 2

Advanced Cardiovascular Life Support (ACLS)

Rhythm Assessment and Management

The ACLS algorithm differentiates between shockable rhythms (ventricular fibrillation [VF] and pulseless ventricular tachycardia [pVT]) and non-shockable rhythms (pulseless electrical activity [PEA] and asystole) 1:

Shockable Rhythms (VF/pVT)

1. Deliver one shock
   • Biphasic: 120-200 J (manufacturer recommendation)
   • Monophasic: 360 J
2. Resume CPR immediately for 2 minutes
3. Establish IV/IO access
4. Administer epinephrine 1 mg IV/IO every 3-5 minutes
5. Consider advanced airway
6. After 2 minutes, check rhythm and pulse
7. If persistent VF/pVT, deliver another shock and resume CPR
8. Consider antiarrhythmic medications:
   • Amiodarone: First dose 300 mg IV/IO bolus, second dose 150 mg
   • OR Lidocaine: First dose 1-1.5 mg/kg, second dose 0.5-0.75 mg/kg 1, 2

Non-Shockable Rhythms (PEA/Asystole)

1. Begin CPR immediately
2. Establish IV/IO access
3. Administer epinephrine 1 mg IV/IO as soon as possible, repeat every 3-5 minutes
4. Consider advanced airway
5. After 2 minutes, check rhythm and pulse
6. If organized rhythm, check for pulse
7. If no pulse, continue CPR and epinephrine 1

Vascular Access

It is reasonable to first attempt establishing IV access for drug administration in cardiac arrest (Class 2a, LOE B-NR). IO access may be considered if attempts at IV access are unsuccessful or not feasible (Class 2b, LOE B-NR) 1.

Advanced Airway Management

• Endotracheal intubation or supraglottic airway placement
• Confirm placement with waveform capnography
• Once advanced airway is placed, deliver 1 breath every 6 seconds (10 breaths/minute) with continuous chest compressions 1, 2
• Disconnect patients from mechanical ventilators during CPR and use manual ventilation devices to avoid excessive ventilation from erroneous triggering 3

Monitoring CPR Quality and ROSC

CPR Quality Indicators

• Quantitative waveform capnography
• If PETCO₂ < 10 mm Hg, attempt to improve CPR quality
• Intra-arterial pressure monitoring: aim for diastolic pressure > 20 mm Hg 1

Signs of Return of Spontaneous Circulation (ROSC)

• Palpable pulse and measurable blood pressure
• Abrupt sustained increase in PETCO₂ (typically ≥ 40 mm Hg)
• Spontaneous arterial pressure waves with intra-arterial monitoring 1, 2

Reversible Causes (H's and T's)

Always consider and treat potential reversible causes of cardiac arrest:

• H's: Hypovolemia, Hypoxia, Hydrogen ion (acidosis), Hypo/hyperkalemia, Hypothermia
• T's: Tension pneumothorax, Tamponade (cardiac), Toxins, Thrombosis (pulmonary), Thrombosis (coronary) 1, 2

Special Circumstances

Cardiac arrest due to special circumstances such as asphyxia, trauma, pulmonary embolism, accidental hypothermia, anaphylaxis, or during pregnancy may require additional specific interventions to address reversible causes during resuscitation 4.

Common Pitfalls to Avoid

• Delaying chest compressions to remove clothing
• Interrupting compressions for more than 10 seconds to check pulse
• Over-ventilating the patient (increases intrathoracic pressure and decreases venous return)
• Terminating resuscitation prematurely, especially in PEA that may convert to ROSC 2
• Focusing on advanced interventions at the expense of high-quality CPR
• Failing to consider and treat reversible causes

The 2020 AHA guidelines emphasize that high-quality CPR with minimal interruptions remains the foundation of successful resuscitation, with early defibrillation for shockable rhythms and prompt administration of epinephrine being critical interventions that improve survival outcomes 1.