Infant Blood Pressure
The normal blood pressure in a newborn varies with age after birth and state (sleeping, awake, crying, etc.) but is approximately 70 (+/- 9) over 42 (+/- 12) at 24 hours of age. By one month, the normal blood pressure is 85 (+/- 10) over 46 (+/- 9). By 6 months it is about 93 (+/- 14) over 55 (+/-9) and by one year of age it is about 94 (+/-11) over 56 (+/-8).
In infants the flush and Doppler methods of blood pressure measurement are usually used. The flush method measures mean pressure; the Doppler method, systolic and diastolic pressures. Normal flush values from 1 to 12 months of age do not exceed 100 mm of mercury; Doppler systolic levels do not exceed 113 mm of mercury.
Data concerning normal limits for children and adolescents are conflicting. For practical purposes, a persistent pressure of 140 mm of mercury systolic or 90 mm of mercury diastolic in patients more than 10 years of age is indicative of hypertension. In those younger than 10 years, systolic pressure does not normally exceed 130 mm of mercury and diastolic pressure does not normally exceed 85 mm of mercury.
Primary hypertension is relatively infrequent in pediatric patients and diagnosis should be made with deliberation and caution. Antihypertensive drug therapy is indicated only for severe hypertension and in selected cases of moderate hypertension.
