Pulsus paradoxus is defined as what change in systolic blood pressure with inspiration?

Pulsus paradoxus is defined as what change in systolic blood pressure with inspiration?

• A. >10 mm Hg decrease in SBP with inspiration
• B. Increase by 10 mm Hg
• C. No change
• D. Decrease by 5 mm Hg

Answer: (A)

Pulsus paradoxus is an exaggerated drop in systolic blood pressure during inspiration. Normally the systolic pressure may fall a small amount with inspiration, but when the drop exceeds about 10 mm Hg, it is considered pulsus paradoxus. The mechanism involves the normal fall in intrathoracic pressure during inspiration increasing venous return to the right heart, which in turn can shift the interventricular septum and reduce left ventricular filling. This causes the stroke volume and thus the systolic pressure to fall more than usual. This phenomenon is classically associated with conditions like cardiac tamponade and severe obstructive lung disease, and it’s defined by a decrease in SBP greater than 10 mm Hg with inspiration. Therefore, the correct description is a decrease in systolic blood pressure of more than 10 mm Hg with inspiration. The other options do not fit this diagnostic threshold.

Pulsus paradoxus is an exaggerated drop in systolic blood pressure during inspiration. Normally the systolic pressure may fall a small amount with inspiration, but when the drop exceeds about 10 mm Hg, it is considered pulsus paradoxus. The mechanism involves the normal fall in intrathoracic pressure during inspiration increasing venous return to the right heart, which in turn can shift the interventricular septum and reduce left ventricular filling. This causes the stroke volume and thus the systolic pressure to fall more than usual. This phenomenon is classically associated with conditions like cardiac tamponade and severe obstructive lung disease, and it’s defined by a decrease in SBP greater than 10 mm Hg with inspiration. Therefore, the correct description is a decrease in systolic blood pressure of more than 10 mm Hg with inspiration. The other options do not fit this diagnostic threshold.