gnu -

I haven't checked the books yet, but I believe that the condition you found does refer primarily to a vertigo associated with inner ear and/or nerve problems. Her doctor should be able to determine from examination whether that specific condition is likely in her case, and may have made such an examination.

A more general, and probably more common "postural hypotension" that can cause brief vertigo often occurs just from standing up from a sitting or prone position. Quite simply, if you were relaxed immediately before standing, your blood pressure and heart rate may be at their lowest. When you stand up quickly, gravity produces a pressure gradient between head and the rest of the body. It takes a moment for the circulation to "adjust" to the higher pressure required to pump blood uphill to the head, so the brain (all that generalized "stuff" that occupies the headbone) momentarily experiences a loss of circulation. The common "the blood runs out of your head" description is not really accurate, but the flow may "pause in place" until the circulatory system adjusts to the different pumping pressure needed to compensate for the head being suddenly higher.

This is generally considered a "benign" event, and about the only thing you can do about it is be aware that it happens and prevent falls that could cause injury. Usually just standing still for a moment or two takes care of it. It is sometimes suggested that persons who experience this should "get ready to stand up" by doing a few head swivels and some arm and leg motions before actually rising, just to "prime the pump," and this may be helpful for some.

This kind of postural hypotension can occur in people of any age, but often becomes more common in the elderly simply because their circulatory system becomes a little slower with its response. In the very elderly, sitting or lying down often is associated with much less "fidgeting" and the circulation may "relax" more than in younger persons. It may also seem to become more frequent simply because an elderly person may be much more concerned about the possibility of a fall, may be less certain of their ability to grab something for support that feels secure, and will likely pay more attention to these events - and report them as a concern.

There are numerous causes and conditions that can result in "postural vertigo," and the "text book symptoms" are pretty much the same for all of them. It requires examination of the patient to make any sort of confident evaluation, and to assign the symptoms to a particular cause. Her doctor may, or may not, have considered all possibilities; but it is quite true that some kinds of posture-related vertigo is more commonly reported by elderly patients. In many cases recommending caution to prevent falls is about all that can be done.

John