Immediate orthostatic hypotension: diagnostic value in acutely ill patients.

Hypotension (systolic blood pressure less than 90 mm Hg) was induced immediately in 21 acutely ill normotensive patients when they were raised from a supine to an upright position. Systolic blood pressure declined to 80 mm Hg or lower in all patients and to 65 mm Hg or lower in 10 patients when they assumed an upright posture. Immediate orthostatic hypotension observed in 9 patients suggested hypovolemia, which was promptly corrected by rapid infusion of large volumes of normal saline and/or albumin. Orthostatic hypotension was of diagnostic aid in 16 patients, including 4 with infections (pelvic inflammatory disease, occult septic shock, legionnaires' disease, Rocky Mountain spotted fever), 3 with adrenal insufficiency, 2 with acute myocardial infarction, 1 with hypoglycemia, 2 with severe cardiac valvular obstruction, and 4 with inappropriate drug use (enalapril or trazodone). These findings suggest that immediate orthostatic hypotension in acutely ill patients is a physical sign that might have valuable diagnostic and therapeutic implications.