Focused cardiac ultrasound (FoCUS) can provide critical information quickly to determine the etiology after cardiac arrest and may expedite a diagnosis in order to identify underlying treatable causes. We present a case of reversible acute left ventricular dysfunction after cardiopulmonary resuscitation following attempted suicide by hanging presenting with severe hypoxemia. FoCUS revealed findings consistent with severe left ventricular dysfunction, and point-of-care ultrasound (PoCUS) ruled out pneumothorax. These findings, in conjunction with the clinical presentation, facilitated an early identification and rapid evaluation of cardiogenic shock; furthermore, they led to the use of FoCUS, which can provide critical information quickly on site for a patient who is suddenly symptomatic after severe mechanical asphyxia in the pediatric emergency department, pediatric intensive care unit, or the prehospital setting.