Consider this scenario. A young patient presents with acute respiratory failure and shock requiring mechanical ventilatory support. She has a nondiagnostic supine chest radiograph and a history of a cardiomyopathy. Physical examination fails to reveal a definite diagnosis. Chest CT scans with contrast, echocardiogram, and lower extremity ultrasound duplex study are ordered. While waiting for these results, the care team starts the patient on heparin, inotropes, and vasopressors and begins antibiotics.