Beck's triad is associated with which traumatic condition?

• A. Cardiac tamponade
• B. Tension pneumothorax
• C. Myocardial infarction
• D. Aortic dissection

Answer: (C)

Beck's triad points to cardiac tamponade. In tamponade, blood or other fluid collects in the pericardial sac after trauma, squeezing the heart and preventing it from filling properly during diastole. This reduces stroke volume and cardiac output, causing low blood pressure. The backup of blood in the venous system raises jugular venous pressure, and the fluid around the heart muffles its sounds, making them seem distant or faint. In a trauma setting, this is an emergency: rapid recognition with tools like a FAST ultrasound helps confirm a pericardial effusion, and definitive treatment is emergent pericardiocentesis or surgical drainage along with aggressive resuscitation. While tension pneumothorax can also cause hypotension and neck vein distention, it typically presents with unilateral absent breath sounds and hyperresonance, not the muffled heart sounds of tamponade. Myocardial infarction and aortic dissection produce chest symptoms and signs of their own and do not present with Beck's triad.