The Nurse Is Caring for a Patient Who Has Had

The nurse is caring for a patient who has had cardiac surgery, and the nurse notes that the chest tube drainage has decreased, and the patient has muffled heart sounds and pulsus paradoxus. Which of the following echocardiographic findings suggest a diagnosis of cardiac tamponade?

A) Exaggerated increase in left ventricular outflow tract velocity during inspiration
B) Exaggerated increase in mitral flow velocity during inspiration
C) Collapse of right ventricular outflow tract during early diastole
D) Exaggerated decrease in mitral flow velocity during inspiration