BLOOD PRESSURE MEASUREMENT

• All children >3 years old should have blood pressure (BP) measured as part of their physical exam.
• If <3 years old, measure BP if there are comorbidities present that predispose them to hypertension (congenital heart disease, neonatal intensive care unit [NICU] stay, recurrent urinary tract infection [UTI], proteinuria, renal disease).
• Measure BP in the right upper arm for purposes of consistency, comparability to standard tables, and to avoid a spurious value in cases of coarctation.
• BP by auscultation is the preferred method.
• Abnormal BPs obtained by oscillometry should be confirmed by auscultation.
• Optimal BP cuff size (Table 1):
  Table 1. Recommended Dimensions for BP Cuff Bladders

  Age Range	Width, cm	Length, cm	Maximum ArmCircumference, cma
  Newborn	4	8	10
  Infant	6	12	15
  Child	9	18	22
  Small adult	10	24	26
  Adult	13	30	34
  Large adult	16	38	44
  Thigh	20	42	52

  ^aCalculated so that the largest arm would still allow the bladder to encircle arm by at least 80%. BP, blood pressure.

  Source: National Heart, Lung, and Blood Institute; National Institutes of Health; U.S. Department of Health and Human Services.

  • Bladder length covers 80–100% of the circumference of the arm.
  • Bladder width covers 40% of the upper arm circumference.
• Refer to BP standards based on gender, age, and height that now include 50th, 90th, 95th, and 99th percentiles (Tables 2 and 3).
• Hypertension is defined as average systolic BP (SBP) and/or diastolic BP (DBP) that are ≥95th percentile for gender, age, and height on three occasions.
• Prehypertension: If the SBP or DBP is ≥90th percentile and <95th percentile, it is called “prehypertension.”
• Primary hypertension is usually diagnosed in postpubertal child with overweight/obesity and positive family history of primary hypertension.
• Secondary hypertension is more likely than primary hypertension in a prepubertal child
• Differential diagnosis for secondary causes of hypertension in pediatrics includes chronic kidney disease, renal artery stenosis, sleep disordered breathing, history of prematurity, and aortic coarctation, endocrine disorders, and environmental exposures.
• Aortic coarctation: If suspected, check BP in all four extremities. A difference >10 mm Hg between upper and lower extremity BPs is pathologic and suggests the presence of aortic coarctation, aortic arch hypoplasia, or interrupted aortic arch.
• Hypertension treatment goals: Behavioral goals: nonsmoking, normal BMI, physical activity, healthy diet. Three ideal health factors: normal total cholesterol, normal fasting blood glucose, normal BP for age and height.