Orthostatic hypotension
Orthostatic hypotension is a sustained fall in blood pressure on standing (at least 20 mmHg systolic or 10 mmHg diastolic), causing lightheadedness, presyncope, and falls. Causes include volume depletion, drugs, and autonomic failure; management is removing offenders, nonpharmacologic measures, and, when needed, fludrocortisone or midodrine.
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What this article covers
- Overview
Definition: orthostatic hypotension is a sustained fall in blood pressure of at least 20 mmHg systolic or 10 mmHg diastolic within 3 minutes of standing (or head-up tilt).
- Epidemiology
Common, especially in older adults and those on multiple medications.
- Risk factors
Older age and polypharmacy. Volume depletion: dehydration, hemorrhage, and diuretics.
- Pathophysiology
Impaired orthostatic compensation: on standing, blood pools in the legs, and normally reflex vasoconstriction and tachycardia maintain pressure.
- Clinical features
Lightheadedness, presyncope, and visual dimming on standing.
- Differential diagnosis
Reflex (vasovagal) syncope: transient loss of consciousness after a trigger with a prodrome, distinguished by the absence of a sustained orthostatic blood-pressure fall on standing measurement (Syncope).
- Diagnosis
Establish by orthostatic blood-pressure measurement showing the defining fall, then determine the cause: the diagnostic basis is measuring supine and standing blood pressure and heart rate…
- Management
First-line, remove offenders and use nonpharmacologic measures: review and reduce vasoactive drugs, ensure adequate hydration and salt intake, and teach physical counter-maneuvers, slow position changes, and compression garments.
- Complications
Falls and fractures. Syncope and injury. Supine hypertension from treatment.
- Prognosis
Good when reversible causes are corrected.
- Prevention
Adequate hydration and salt (fluid 2 to 3 L and salt 6 to 10 g daily, where not contraindicated).
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Related articles
- Syncope
Syncope is a transient loss of consciousness from global cerebral hypoperfusion with spontaneous complete recovery. The central task is separating benign reflex and orthostatic causes from dangerous cardiac syncope, using history, examination, and ECG, since cardiac syncope carries a risk of sudden death; treatment is directed by mechanism, from reassurance and hydration for reflex syncope to a pacemaker, ICD, or structural intervention for cardiac syncope.
- Postural orthostatic tachycardia syndrome
Postural orthostatic tachycardia syndrome is an excessive heart-rate rise on standing (at least 30 beats per minute) with orthostatic symptoms but without orthostatic hypotension. It predominantly affects young women, is diagnosed after excluding other causes, and is managed with volume expansion, exercise reconditioning, and rate-modulating drugs.
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Essential (primary) hypertension is chronically elevated blood pressure without an identifiable secondary cause, the overwhelming majority of hypertension. It is a leading modifiable driver of stroke, heart failure, and kidney disease, and management combines lifestyle change with staged pharmacotherapy to a target usually below 130/80 mmHg.
- Aortic stenosis
Aortic stenosis is obstruction to left ventricular outflow from a narrowed aortic valve, most often calcific degeneration in older adults or a bicentric bicuspid valve earlier in life. Symptoms of angina, syncope, or heart failure mark a poor prognosis, and severe symptomatic disease is treated with valve replacement (surgical or transcatheter).