Pulseless Electrical Activity

Pseudo-Electromechanical Dissociation (Pseudo-EMD)
1. Obese patients with Hypotension may have pulses difficult to palpate and may appear to be in EMD or PEA
2. Bedside Emergency Echocardiogram can distinguish from EMD (e.g. cardiac standstill)
3. Empiric fluid bolus and consider Vasopressors

See Asystole (identical Epinephrine protocol)
1. However empiric cause management differs from Asystole (see below)
2. Atropine is no longer indicated for slow PEA (as of 2010)
Assess Blood Flow
Consider causes as above and treat appropriately
1. See Reversible Causes of Cardiopulmonary Arrest (5H5T)
2. Most PEA patients have organized cardiac activity, but have a Blood Pressure too low to detect via pulse
  1. On Bedside Ultrasound, 85% of PEA patients have mechanical cardiac contractions (see Pseudo-EMD above)
  2. Bocka (1988) Ann Emerg Med 17(5): 450-2 [PubMed]
3. Fluid bolus (single most likely intervention to reverse PEA)
4. Consider Vasopressors (e.g. Epinephrine infusion)
5. Maximize oxygenation and ventilation (place Advanced Airway)
6. Decompress Tension Pneumothorax
7. Pericardiocentesis for Cardiac Tamponade
8. Fibrinolytics if massive Pulmonary Embolism or Myocardial Infarction is suspected
  1. Massive Pulmonary Embolism causes 5-10% of PEA arrests
  2. TPA (50 mg IV) given early (mean 6 min from start of CPR) for high suspicion PE had 85% longterm survival
    1. Sharifi (2016) Am J Emerg Med 34(10):1963-7 +PMID: 27422214 [PubMed]

Background
1. Simplified and more directed approach to PEA compared with ACLS
2. Eliminates Hypoglycemia and Hypokalemia from the 5H5T algorithm (unlikely to present with PEA)
3. Eliminates Hypothermia and Hypoxia from the 5H5T algorithm (identified readily with other measures and history)
Electrocardiogram with NARROW QRS Complex
1. Bedside Cardiac Ultrasound
  1. Hyperdynamic left ventricle
2. Causes: Right ventricular inflow or outflow problems
  1. Cardiac Tamponade
  2. Tension Pneumothorax
  3. Mechanical hyperinflation (e.g. COPD)
  4. Pulmonary Embolism
  5. Severe Hypovolemia
  6. Acute Myocardial Infarction with myocardial rupture
3. Management
  1. Intravenous Fluid bolus AND
  2. Treat underlying cause (e.g. needle decompression, Thrombolytics, Pericardiocentesis)
4. Precautions
  1. Aggressive Mechanical Ventilation and Chest Compressions may exacerbate RV inflow and outflow obstruction
Electrocardiogram with WIDE QRS Complex
1. Bedside Cardiac Ultrasound
  1. Hypokinetic or akinetic left ventricle
2. Causes: Toxic or Metabolic problem
  1. Severe Hyperkalemia
  2. Sodium-channel blocker toxicity
  3. Agonal rhythm
  4. Acute Myocardial Infarction with pump failure
3. Management
  1. Empiric Calcium Chloride IV and Sodium Bicarbonate IV
  2. Treat specific causes
References
1. Littmann (2014) Med Princ Pract 23(1):1-6 [PubMed]

PEA survival is very poor (8.8% in one study)
1. Good neurologic outcome in only 6.5%
2. Heart Rate and QRS width do not appear to alter survival
3. Hauck (2015) Am J Emerg Med 33(7): 891-4 +PMID: 25943040 [PubMed]