Trends with Age: Unlike other vital signs, blood pressure starts low and increases with
age. The normal ranges for blood pressure depend on a child’s age, gender, and height,
but here are some good numbers to remember. In a term neonate, systolic blood
pressure should be higher than 60 mm Hg. In a child aged 1 to 10 years, the minimum
systolic blood pressure can be determined using the formula 70 + (age in years x 2).
For example, the minimum systolic pressure for an 8 year old would be 70 + (8 years x
2) = 86 mm Hg. For children older than 10, systolic blood pressure should be higher
than 90. For precise determination of a child’s blood pressure percentile, as is needed
to diagnose hypertension, specific reference ranges are available from the National
High Blood Pressure Education Program Working Group. You can also calculate the
child’s percentile using medical calculator apps.
Hypotension, or abnormally low blood pressure is a very late sign of shock in children,
including hypovolemic, septic, distributive and cardiogenic shock. Unlike adults, children
compensate during shock and maintain an adequate blood pressure; hypotension is an
ominous sign of impending deterioration. Hypertension can be suggestive of a number
of problems including renal disease, coarctation of the aorta, endocrine disorders,
medication side effects, intoxications and increased intracranial pressure.