Final answer:
A patient presenting with decreasing blood pressure, increasing heart rate, and jugular venous distention likely has pericardial tamponade, a form of obstructive shock requiring quick medical intervention.
Step-by-step explanation:
The assessment findings of a patient with a chest injury who presents with a series of declining blood pressures, rising pulse rate, and the development of jugular venous distention should raise concerns for pericardial tamponade. Specifically, the findings of hypotension (BP of 90/74 mm Hg), tachycardia (pulse of 120 beats/min), and jugular venous distention are consistent with this diagnosis. Pericardial tamponade occurs when excess fluid in the pericardial cavity interferes with the ability of the heart to fully relax and fill with blood, resulting in decreased preload and compromised cardiac output. This condition is considered an obstructive form of shock and requires immediate medical intervention, potentially including the removal of fluid from the pericardial cavity to alleviate the tamponade.