Your patient is a 15-year-old male with a stab wound along the right sternal border at the fourth intercostal space. The patient responds to painful stimuli, and shows little evidence of external bleeding. His respirations are 30, his breath sounds are clear and equal, and his radial pulse is weak and disappears on inspiration. The patient has distended jugular veins and is dyspneic. This patient is most likely suffering from ________ shock due to ________.

A) obstructive, pericardial tamponade
B) hypovolemic, hemothorax
C) distributive, loss of sympathetic nervous tone
D) hypoxic, tension pneumothorax

A) obstructive, pericardial tamponade