In a patient on diuretics, which assessment would best detect orthostatic hypotension?

• A. Daily weight
• B. Measuring standing blood pressure
• C. Temperature
• D. Urine output

Answer: (B)

Detecting orthostatic hypotension requires observing how blood pressure responds to a change in position, especially when volume may be reduced by diuretics. The best assessment is measuring blood pressure in different positions—typically first after lying down, then after standing for 1 to 3 minutes—and comparing the values. If systolic pressure drops by about 20 mm Hg or more, or diastolic pressure drops by about 10 mm Hg, when moving to standing (often with a compensatory rise in heart rate), orthostatic hypotension is indicated. This direct, positional BP assessment shows whether the cardiovascular system fails to maintain cerebral perfusion on standing, which diuretic-induced volume loss can cause. Daily weight reflects overall fluid balance over time but won’t reveal the immediate standing BP change; temperature is not related to orthostatic hypotension; and urine output shows diuretic effect or hydration status but not the acute hemodynamic response to standing.