Orthostatic (postural) hypotension is defined as a drop of 20 mm Hg in systolic blood pressure and 10 mm Hg diastolic blood pressure on standing, associated with typical symptoms.
It is important to estabilish a consistent supine blood pressure before checking standing blood pressure. Otherwise an incorrect diagnosis may be made.
Lying BP should be repeated until a reproducible reading is obtained. Standing BP and heart rate should then be measured immediately on standing, at 30s, 60s and 120s.
Symptoms of orthostatic hypotension may include light-headedness, darkening of vision, and inability to remain upright.
Patients may also complain of so-called Coat Hanger pain. This is caused by reduced oxygen supply to muscles in the neck and shoulder girdle.