Inaccuracy in pediatric outpatient blood pressure measurement

Hypertension is common in the pediatric population. There is increasing evidence for early hypertensive target organ damage that may lead to substantial long-term morbidity. Because a critical aspect of any screening program for hypertension is the ability to measure blood pressure accurately, we compared typical blood pressure measurements at a vital sign station with those that were obtained following recommendations set forth in "The Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents."

We compared the blood pressure measurements that were obtained with standard practice vital sign station screening with those that were obtained by trained personnel in accordance with Fourth Task Force recommendations. A total of 390 children were evaluated at 580 visits to the Pediatric Hypertension Clinic at Texas Children's Hospital.

Seventy-four percent of the readings were higher at the vital sign station, and only 12% differed by <5 mm Hg for both systolic blood pressure and diastolic blood pressure. The mean difference between vital sign station and examination room was 13.2 +/- 8.9 mm Hg for systolic blood pressure and 9.6 +/- 7.6 mm Hg for diastolic blood pressure. Multiple regression analyses revealed that age, gender, race, obesity, first versus subsequent visit, essential versus secondary, or white coat hypertension and antihypertensive medications made no statistically significant difference in the lack of correlation of the readings.

These results suggest that if pediatricians use vital sign station screening for blood pressure, children with elevated initial measurements must be reevaluated in the examination room.