Orthostatic hypotension is defined as?

• A. Any blood pressure decrease after standing.
• B. A drop in systolic blood pressure of ≥20 mmHg or diastolic ≥10 mmHg within 3 minutes of standing.
• C. An increase in blood pressure while standing.
• D. A drop in heart rate of ≥20.

Answer: (B)

Standing causes blood to pool in the legs, and a healthy autonomic response should tighten vessels and raise heart rate to keep blood pressure from dropping. When that response is insufficient, a significant fall in blood pressure occurs after standing. The defining clinical criterion is a drop in systolic blood pressure of 20 mmHg or more, or a drop in diastolic blood pressure of 10 mmHg or more, within 3 minutes of standing. This specific threshold within the short time frame makes the finding reliable for diagnosing orthostatic hypotension.

To assess it, measure the patient’s blood pressure and heart rate after a period of rest lying down, then have them stand and recheck at about 1 and 3 minutes. Be mindful of factors that can contribute, such as dehydration, medications (like diuretics or vasodilators), or autonomic dysfunction, which can exaggerate the drop. If the BP drop meets the threshold and the patient has symptoms like dizziness or lightheadedness, it supports the diagnosis.

The other statements don’t fit because an arbitrary BP decrease after standing isn’t specific enough, an increase in BP while standing is the opposite of the condition, and a drop in heart rate is not the defining feature of this diagnosis.