Patient presented in pulseless electrical activity (PEA) arrest.  Initial presentation included unresponsiveness, absence of palpable pulses, and observed electrocardiogram (ECG) rhythm showing organized electrical activity without corresponding mechanical cardiac contractions.  Differential diagnosis for PEA arrest considered hypovolemia, hypoxia, hydrogen ion (acidosis), hyperkalemia or hypokalemia, hypothermia, tension pneumothorax, tamponade (cardiac), toxins (drug overdose), thrombosis (pulmonary embolism, coronary), and trauma.  Advanced cardiac life support (ACLS) protocol initiated immediately.  High-quality cardiopulmonary resuscitation (CPR) commenced, including chest compressions and ventilation with supplemental oxygen.  Intravenous (IV) access established and continuous cardiac monitoring maintained.  Point-of-care ultrasound (POCUS) performed to evaluate for potential causes of PEA, such as pericardial effusion or pneumothorax.  Arterial blood gas (ABG) analysis obtained to assess acid-base status and electrolyte imbalances.  Treatment focused on identifying and correcting the underlying cause of the PEA arrest while continuing CPR.  Epinephrine administered intravenously per ACLS guidelines.  Patient's medical history reviewed for potential contributing factors, including current medications, comorbidities, and recent illnesses or injuries.  Response to treatment documented continuously.  Prognosis and potential for return of spontaneous circulation (ROSC) discussed with medical team and family members as appropriate.  Further diagnostic testing and interventions considered based on patient response to initial treatment.