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Reversible Causes of Cardiopulmonary Arrest

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Reversible Causes of Cardiopulmonary Arrest, 5H5T, 6H6T, Never Carry Bling Through Gloomy Antwerp Mnemonic, Empiric Measures to Consider in Cardiac Arrest, Ultrasound Evaluation of Cardiac Arrest Reversible Causes

  • Conditions
  1. Cardiopulmonary Arrest
  2. Arrhythmia
  3. Pulseless Electrical Activity
  4. Ventricular Tachycardia
  5. Ventricular Fibrillation
  6. Supreventricular Tachycardia
  • Background
  1. Mnemonic: 6H 6T
  • Causes
  • Six H's
  1. Hypovolemia
  2. Hypoxia
  3. Hydrogen Ion (Metabolic Acidosis)
  4. Hyperkalemia
  5. Hypokalemia
  6. Hypothermia
  • Causes
  • Six T's
  1. Tablets or Toxins (Unknown Ingestion)
    1. Tricyclic Antidepressant Overdose
    2. Digitalis Toxicity
    3. Beta Blocker Overdose
    4. Calcium Channel Blocker Overdose
  2. Tamponade (Cardiac Tamponade)
  3. Tension Pneumothorax
  4. Thrombosis: Myocardial Infarction
  5. Thrombosis: Pulmonary Embolism
  6. Trauma
  • Causes
  • Other
  1. Subarachnoid Hemorrhage (5% of Cardiac Arrests)
    1. Cardiac Arrest triggered by Catecholamine surge with Macrophage infiltration into left ventricle
  1. See Echocardiogram
  2. Precautions
    1. Ultrasound during pulse checks doubles the time without Chest Compressions
    2. Have staff count down during pulse check from 10 to 0, and remove Ultrasound probe at 2
    3. Consider recording a 6 second Ultrasound video that can be reviewed after Chest Compressions resume
    4. Avoid using with each pulse check (only use with specific goal, e.g. confirm Asystole)
  3. General Ultrasound Findings of reversible cause
    1. Cardiac Tamponade
    2. Hypovolemia
      1. Small left ventricle
      2. Narrow inferior vena cava
    3. Tension Pneumothorax
      1. B-Line artifacts may be difficult to see in Cardiac Arrest (may see during Chest Compressions, ventilations)
    4. Myocardial Infarction
      1. Regional wall motion abnormalities may be seen in Peri-Arrest patients
    5. Pulmonary Embolism
      1. Right ventricular dilatation is non-specific but may indicate Pulmonary Embolism
      2. Clot in transit (seen in cardiac chambers) is assumed to be associated with Pulmonary Embolism
      3. Consider Focused Lower Extremity Venous Ultrasound (2 point) for DVT
    6. Hemorrhagic Shock (e.g. Ruptured Abdominal Aortic Aneurysm, Trauma)
      1. FAST Exam
  4. Cardiac activity definition
    1. Intrinsic myocardial movement
    2. Isolated cardiac valve movement occurs with minimal Fluid Shifts (3 mmHg) and is NOT cardiac activity
    3. Absence of cardiac activity on ulrasound is not recommended as a prognostic indicator (AHA 2020)
      1. ROSC is ultimately achieved in 2.4% of patients without wall motion on Ultrasound
        1. Blyth (2012) Acad Emerg Med 19(10):1119-26 +PMID: 23039118 [PubMed]
      2. Cardiac standstill has variable inter-rater reliability
        1. Hu (2018) Ann Emerg Med 71(2):193-8 +PMID: 28870394 [PubMed]
  5. Compression quality
    1. Consider using Ultrasound over the femoral artery to follow circulation, compression quality
  6. References
    1. Swaminathan and Avila in Swadron (2021) EM:Rap 21(12): 5-8
    2. Swaminathan, Andrus and Mallon in Herbert (2018) EM:Rap 18(1): 8-9
    3. Orman and Reed in Herbert (2018) EM:Rap 18(3): 3-4
    4. Huis (2017) Resuscitation 119:95-8 +PMID:28754527

  • Management
  • Empiric Therapies
  1. Six empiric therapies to consider in Cardiac Arrest
  2. Mnemonic: "Never Carry Bling Through Gloomy Antwerp"
    1. Needle
      1. Emergency Pericardiocentesis (Cardiac Tamponade)
      2. Needle Thoracostomy (Tension Pneumothorax)
    2. Calcium
      1. Calcium Chloride stabilizes Myocardium (e.g. Hyperkalemia)
    3. Blood (or fluid Resuscitation)
      1. NS or LR bolus (Hypovolemic Shock)
    4. Thrombolytics (e.g. tPA 50 mg)
      1. Massive Pulmonary Embolism
    5. Glucose
      1. See Hypoglycemia Management
    6. Antidote
      1. See Toxin Antidote
  3. References
    1. Strayer in Herbert (2015) EM:Rap 15(8): 4-5
  1. http://www.circulationaha.org
  2. (2010) Guidelines for CPR and ECC [PubMed]
  3. (2005) Circulation 112(Suppl 112):IV [PubMed]
  4. (2000) Circulation, 102(Suppl I):86-9 [PubMed]