Check out the calculator below!
Hypertension
Hypertension is frequently encountered in the inpatient and outpatient settings. Blood pressure has many inputs, (CO x SVR), which may be impacted by fluids, hormones, emotional state, pain etc.
In the inpatient setting, up to a third of hospitalized pediatric patients may have hypertension. We rule out secondary causes (pheochromocytoma, renal parenchymal disease, thyroid disease, medications such as steroids etc., see below).
In the outpatient setting,, pediatric HTN prevalence is increasing. per the AAP guidelines (differs slightly from European and Canadian guidelines), if a patient is > 6 years old, has obesity, and family history of HTN and no concerning features, they do not need to undergo the full secondary work up (see below). It has been observed that hypertension due to obesity is unlikely to be significantly higher than low-ish Stage 2 hypertension. If said patient does have significant Stage 2 hypertension , I consider performing the secondary workup.
Inpatient, my general practice is treat as necessary for elevated blood pressure (i.e. isradipine) to avoid complications such as PRES while also trying to control other factors (agitation, pain etc.) to determine if the elevated blood pressure is genuine or due to modifiable factors that can be managed/treated. If the hypertension persists, I will then start a long acting medication.
Of note, automated blood pressure machines are fraught with errors.
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They measure the MAP and derive SBP and DBP from there.
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Each individual vendor has a proprietary algorithm for how the measurements are obtained and translated into SBP and DBP, limiting ability to match results across machines.
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The cuff may deflate and inflate, as well as remain inflated while trying to obtain a blood pressure reading, causing discomfort and (ironically?) raising blood pressure
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There is an initial reading effect, where the first BP is often high. General practice is to take 3 measurements and use the average if BP>90th%ile, and if still elevated, to perform auscultatory blood pressure measurement.
Checking blood pressure should be performed:
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With the appropriate sized cuff
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Both of the patients feet flat on the ground (not crossed) and in a calm state
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Back supported
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Arm supported at heart level
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Patient should not be speaking and have empty bowel/bladder
The AAP offers guidance in the outpatient setting as outlined below.
Calculator (Ages 1-18) for BP percentiles by age, sex, and height
50th%ile
90th%ile
95th%ile
95th%ile+12
* = height <5th percentile; lower age row used
+ = height >95th percentile; higher age row used
S = systolic threshold limited by adult cutoff
D = diastolic threshold limited by adult cutoff
