A 32-year-old woman with a history of systemic lupus erythematosus presents to the emergency department complaining of severe shortness of breath and sharp chest pain that worsens when she lies flat. Her temperature is 37.8°C (100.0°F), blood pressure is 86/48 mm Hg, and pulse is 124/min. The physician strongly suspects acute cardiac tamponade secondary to a pericardial effusion. Based on this suspected diagnosis, which of the following physical examination findings would most likely be present? (Select exactly two)
- A decrease in systolic blood pressure of greater than 10 mm Hg during inspirationCevap
- Distant, muffled heart sounds on precordial auscultationCevap
- CA prominent 'y' descent on the jugular venous pressure waveform
- DBilateral fine inspiratory crackles at the lung bases
- EDisplacement of the point of maximal impulse laterally to the anterior axillary line
Cevap
The correct findings are a decrease in systolic blood pressure of greater than 10 mm Hg during inspiration (pulsus paradoxus) and distant, muffled heart sounds.
Cardiac tamponade restricts cardiac filling due to fluid accumulation in the rigid pericardial space. This results in Beck's triad: systemic hypotension, elevated jugular venous pressure, and muffled or distant heart sounds (because the fluid insulates the acoustic transmission). Furthermore, the fixed pericardial volume enhances ventricular interdependence; during inspiration, increased venous return to the right ventricle causes the interventricular septum to bow into the left ventricle. This decreases left ventricular stroke volume, leading to a drop in systolic blood pressure of > 10 mm Hg during inspiration (pulsus paradoxus).
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Physical examination findings in cardiac tamponade (Beck's triad and pulsus paradoxus)
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