A significant number of falls and fractures, particularly among the elderly, are likely to result from orthostatic hypotension — literally, low blood pressure upon standing. Many an older person has fallen and broken a hip when getting out of bed in the morning or during the night to use the bathroom, precipitating a decline in health and loss of independence as a result of this blood pressure failure.
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Under normal circumstances, when we stand up, gravity temporarily causes blood to pool in the lower half of the body; then, within 20 or 30 seconds, receptors in the heart and carotid arteries in the neck trigger a compensating mechanism called the baroreflex that raises the heart rate and constricts blood vessels to increase blood pressure and provide the brain with an adequate supply of blood.
In people with orthostatic hypotension, this reflex mechanism is delayed or insufficient, resulting in such symptoms as lightheadedness, dizziness, palpitations, blurred vision, weakness, confusion or fainting.
Recommended treatments include wearing compression stockings and an abdominal binder (a girdle) to reduce the pooling of blood upon standing… Also helpful is avoiding prolonged or motionless standing, hot baths or showers, alcohol and carbohydrate-heavy meals. One of the most effective strategies to combat orthostatic hypotension is regular physical exercise. Improving muscle tone in the lower half of the body can counter pooling of blood upon standing.