Question Of The Day #23

This patient presented to the emergency department with acute pleuritic chest pain, dyspnea, and experienced a cardiac arrest prior to a detailed physical examination. The cardiac monitor shows a narrow complex sinus rhythm morphology. In the setting of a cardiac arrest and pulselessness, this cardiac rhythm is known as pulseless electric activity (PEA). PEA includes any cardiac rhythm that is not asystole, ventricular fibrillation, or pulseless ventricular tachycardia. The ACLS algorithm divides the management of patients with pulseless ventricular tachycardia (pVT) or ventricular fibrillation (VF) and patients with pulseless electric activity (PEA) or asystole. Assuming adequate staff and medical resources are present, patients with all of these rhythms receive high-quality CPR, IV epinephrine, and airway management. Patients with pVT or VF receive electrical cardioversion, while patients with PEA or asystole do not receive electrical cardioversion. Patients with PEA or asystole generally have a poorer prognosis than those with pVT or VF. Out of hospital cardiac arrests that present to the emergency department with PEA or asystole on initial rhythm have a survival rate of under 3%. The etiology of PEA in cardiac arrest includes a wide variety of causes. A traditional approach to remembering the reversible causes of PEA are the “Hs & Ts”. The list of the “Hs & Ts” along with their individual treatments are listed in the table below.

Sodium bicarbonate (Choice A) would be the correct choice for a patient whose PEA arrest was caused by severe acidosis. This can occur in severe lactic acidosis (i.e. sepsis), diabetic ketoacidosis, certain toxic ingestions (i.e. iron, salicylates, tricyclic antidepressants), as well as other causes. Calcium gluconate (Choice B) would be the correct choice for a patient whose PEA arrest was caused by hyperkalemia. This can occur in renal failure, in the setting of certain medications, rhabdomyolysis (muscle tissue breakdown), and other causes. Blood products (Choice D) would be the correct choice for a patient whose PEA arrest was due to severe hemorrhage, such as gastrointestinal bleeding or in the setting of traumatic injuries. This patient has symptoms and risk factors for pulmonary embolism, including pleuritic chest pain, dyspnea, and a cancer history. These details make pulmonary embolism the most likely cause of PEA arrest in this scenario. The best treatment for this diagnosis would be thrombolysis (Choice C).