Orthostatic hypotension is indicated by which change after standing?

• A. Systolic BP drops ≥20 mmHg or diastolic BP drops ≥10 mmHg
• B. Systolic BP rises ≥20 mmHg
• C. Pulse drops by 20 bpm
• D. No change in BP

Answer: (A)

Standing can cause blood to pool in the legs, and the body must quickly constrict vessels and raise the heart rate to keep blood flow to the brain. If that response is inadequate, blood pressure falls when you stand. The defining sign is a measurable drop in blood pressure after standing: systolic BP decreases by at least 20 mmHg or diastolic BP decreases by at least 10 mmHg within about 3 minutes of standing. This indicates orthostatic hypotension and can produce dizziness or fainting due to reduced cerebral perfusion. A rise in BP, a decrease in pulse, or no change in BP after standing would not indicate orthostatic hypotension, though sometimes a heart rate increase can accompany autonomic dysfunction even when the BP change is the hallmark being assessed.