Orthostatic changes in normovolemic children: an analysis of the "tilt test".

Abstract

Orthostatic changes in pulse rate and blood pressure were assessed on 455 normovolemic children between 4 and 17 years of age who visited emergency departments with a variety of complaints. Blood pressures and pulse rates were measured in the upper extremity with the patient supine, sitting, and standing. The postural changes in pulse rate and blood pressure for age groups 4 to 9 years, 10 to 13 years, and 14 to 18 years were computed, and statistical analyses were performed to identify factors predisposing to changes in pulse rate and blood pressure. In all categories of chief complaint, comparable numbers (average 25.4%) of patients had an increase in pulse rate of greater than 20 beats/min. An average of 10.7% of children in each category had a fall in systolic blood pressure greater than 20 torr. Only increasing body temperature, especially in the youngest children, and diarrhea, particularly if more than 12 hours in duration, predisposed to having a "positive tilt test" using these criteria. The "tilt test" for assessing orthostatic hypotension is of little value in assessing normovolemic children presenting for acute care. A positive test result is very nonspecific.