Orthostatic hypotension

Orthostatic hypotension (also known as postural hypotension and, colloquially, as head rush) is a sudden fall in blood pressure, typically greater than 20/10 mm Hg, that occurs when a person assumes a standing position.

Symptoms

Symptoms, which generally occur after sudden standing, include dizziness, lightheadedness, headache, blurred or dimmed vision (possibly to the point of momentary blindness), and syncope (temporary loss of consciousness).

Causes

It may be caused by hypovolemia (a decreased amount of blood in the body), resulting from the excessive use of diuretics, vasodilators, or other types of drugs, dehydration, or prolonged bed rest. It also occurs in persons with anemia.

It can be a side effect of certain anti-depressants, such as tricyclics.

The disorder may be associated with Addison's disease, atherosclerosis (build-up of fatty deposits in the arteries), diabetes, and certain neurological disorders including Shy-Drager syndrome and other forms of dysautonomia.

Treatment and management

When orthostatic hypotension is caused by hypovolemia due to medications, the disorder may be reversed by adjusting the dosage or by discontinuing the medication. When the condition is caused by prolonged bed rest, improvement may occur by sitting up with increasing frequency each day. In some cases, physical counterpressure such as elastic hose or whole-body inflatable suits may be required (such as Jobst stockings). Dehydration is treated with salt and fluids.

The prognosis for individuals with orthostatic hypotension depends on the underlying cause of the condition.

Medical management

Some drugs that are used in the treatment of orthostatic hypotension include fludrocortisone (Florinef), erythropoietin and midodrine.

Lifestyle advice

Some suggestions for minimizing the effects include:

Checking blood pressure regularly with a home monitoring kit. Check when lying flat and when standing as well as when symptoms occur.
Standing slowly rather than quickly, as the delay can give the blood vessels more time to constrict properly. This can help avoid incidents of syncope.
Maintaining an elevated salt intake, through sodium supplements or electrolyte-enriched drinks. A suggested value is 10 g per day; overuse can lead to hypertension and should be avoided.
Maintaining a proper fluid intake to prevent the effects of dehydration.
As eating lowers blood pressure, eating multiple smaller meals rather than fewer larger meals. Taking extra care when standing after eating.

References

Adapted from public-domain resource at
Timothy C. Hain, MD. ORTHOSTATIC HYPOTENSION

External links

David H. P. Streeten Orthostatic Disorders of the Circulation: Mechanisms, Manifestations, and Treatment, ISBN 0306423227.
John G. Bradley, M.D., and Kathy A. Davis, R.N. Orthostatic Hypotension American Family Physician
DYNA Dysautonomia Youth Network of America, Inc.
Dysautonomia Information Network

Cardiology

Orthostatische hypotensie