Cardiac Arrest Rhythms and Treatment

Cardiac Arrest Rhythms

Ventricular Fibrillation (VF)

• Treatment:
  • Defibrillation: immediate shock delivery (biphasic 150-200J, monophasic 360J)
  • CPR: continue for 2 minutes before re-analysis
  • Medications: amiodarone or lidocaine (if VF persists after defibrillation)

Ventricular Tachycardia (VT)

• Diagnosis:
  • Wide QRS complex (>140ms)
  • Regular rhythm
  • P-waves not present or dissociated from QRS complex
  • Monomorphic (uniform) QRS shape

Asystole

• Management:
  • Confirm asystole in multiple leads
  • Check for reversible causes (e.g., hypoxia, electrolyte imbalance)
  • CPR: continue until return of spontaneous circulation (ROSC) or termination of resuscitation efforts
  • Medications: none recommended

Pulseless Electrical Activity (PEA)

• Causes:
  • Hypovolemia
  • Hypoxia
  • Hydrogen ions (acidosis)
  • Hypothermia
  • Hypokalemia or hyperkalemia
  • Tamponade (cardiac)
  • Tension pneumothorax
  • Toxic substances
  • Cardiac rupture

Cardiac Arrest Algorithms

• Basic Life Support (BLS):
  • Call for help
  • Check airway, breathing, and circulation (ABC)
  • CPR: 30 chest compressions, 2 breaths
  • Defibrillation (if indicated)
• Advanced Cardiovascular Life Support (ACLS):
  • Rhythm recognition and management
  • Medication administration
  • Cardioversion (if indicated)

Electrocardiogram (ECG)

• Interpretation:
  • P-waves, QRS complex, T-waves
  • Rate, rhythm, axis, and intervals
  • Identification of cardiac arrest rhythms (VF, VT, asystole, PEA)

Test your knowledge of cardiac arrest rhythms, including ventricular fibrillation, ventricular tachycardia, asystole, and pulseless electrical activity. Learn about treatment options and cardiac arrest algorithms.