In-Depth Notes on Emergency Cardiovascular Care

Overview of Cardiovascular Disease

  • Cardiovascular disease affects people globally, leading to significant disability and death.
    • Includes sudden cardiac arrest, acute coronary syndromes, and ischemic stroke.

Cardiac Arrest Statistics

  • In the USA, over half a million people experience cardiac arrests annually.
  • Survival rate is approximately 11% on average, but with improved care, it can reach 75%.

Importance of Systems of Care

  • Understanding the American Heart Association's systems of care is critical.
  • High-performance teams must focus on:
    • Timing
    • Quality
    • Coordination
    • Administration

Immediate Response to Cardiac Arrest

  • Patients in cardiac arrest from ventricular fibrillation or pulseless ventricular tachycardia need:
    • Immediate chest compressions
    • Early defibrillation
  • CPR should continue while preparing the defibrillator, especially with multiple rescuers.
  • Sequence of rescue actions may be adjusted based on the arrest cause (e.g., hypoxia in drowning).

High-Quality CPR Characteristics

  • Defined by:
    • Rate: 100 to 120 chest compressions per minute.
    • Depth: At least 2 inches in adults.
    • Complete chest recoil after each compression.
    • Compression fraction (CCF): At least 60%, ideally >80%.
    • Avoid excessive ventilation.
  • Excellent CPR is correlated to return of spontaneous circulation (ROSC) and better survival outcomes.

Coronary Perfusion Pressure (CPP)

  • Essential for survival and should reach at least 15 mmHg during CPR.
  • Monitoring CPP can be challenging, but:
    • Higher CPP increases survival chances.
  • Providers should use waveform capnography for real-time CPR quality monitoring.

Optimal Compression Techniques

  • Push Hard: Compress to at least 2 inches, ensuring full chest recoil to maintain coronary perfusion.
  • Push Fast: Compress at 100 to 120 per minute:
    • Exceeding 120 compressions may lead to shallower compressions.
    • Switch compressors every 2 minutes or sooner if fatigued.

Minimizing Interruptions During CPR

  • Health care providers often interrupt chest compressions excessively:
    • Aim for a chest compression fraction (CCF) >80%.
    • Spend no more than 10 seconds checking for a pulse or assessing the patient during CPR.
  • CCF calculated as:
    CCF=Total Chest Compression TimeTotal Code TimeCCF = \frac{\text{Total Chest Compression Time}}{\text{Total Code Time}}

Ventilation in CPR

  • Tidal volumes should be about 500 to 600 mL to avoid complications from excessive ventilation, such as:
    • Gastric inflation
    • Increased intrathoracic pressure
    • Decreased venous return to the heart

Integration of Defibrillation and CPR

  • Start defibrillation as early as possible to optimize patient outcomes.
  • Some EMS systems allow initial CPR while preparing for defibrillation.
  • The recommended one shock protocol for treating ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT).