Blood Pressure Percentile

AAP 2017 Clinical Practice Guideline

Based on normative tables for normal-weight children ages 1-17. Flynn et al., Pediatrics 2017;140(3):e20171904.

Age (years)

Sex

Height (cm)

Systolic BP (mmHg)

Diastolic BP (mmHg)

Definitions: Hypertension & Hypotension (AAP 2017 / Nelson)

Hypertension Classification (AAP 2017)

Category	Ages 1 to <13 years	Ages ≥13 years
Normal	<90th percentile	<120/<80 mmHg
Elevated BP	≥90th to <95th percentile OR 120/80 mmHg to <95th (whichever lower)	120-129/<80 mmHg
Stage 1 HTN	≥95th percentile to <95th + 12 mmHg OR 130/80-139/89 mmHg (whichever lower)	130/80 to 139/89 mmHg
Stage 2 HTN	≥95th + 12 mmHg OR ≥140/90 mmHg (whichever lower)	≥140/90 mmHg

Hypertensive Urgency vs Emergency (Nelson)

Hypertensive urgency: Severe BP elevation (>95th + 30 mmHg or >180/120) WITHOUT end-organ damage. Requires reduction over 24-48 hours.
Hypertensive emergency: Severe BP elevation WITH end-organ damage (encephalopathy, heart failure, retinopathy, renal injury). Requires immediate IV therapy with goal reduction of 25% in first 8 hours.

Hypotension (AAP/PALS)

Definition: Systolic BP below the 5th percentile for age, sex, and height.
Quick estimate (1-10 years): Hypotension = SBP < 70 + (2 × age in years) mmHg
Neonates: SBP < gestational age in weeks (term: <60 mmHg)
Clinical significance: Hypotension in children is a late sign of shock. Tachycardia, poor perfusion, and altered mental status typically precede hypotension.

Sources: Flynn JT et al., Pediatrics 2017;140(3). Nelson Textbook of Pediatrics, 21st ed. PALS Provider Manual.

BMI Percentile

CDC Growth Charts, ages 2-20

Based on CDC 2000 growth reference data. For children ages 2-20 years.

Age (years)

Sex

Weight (kg)

Height (cm)

Body Surface Area

Mosteller formula

Mosteller formula: BSA (m2) = sqrt(height(cm) x weight(kg) / 3600)

Weight (kg)

Height (cm)

Weight-Based Dosing

Calculate dose based on weight. Always verify against formulary and institutional guidelines.

Patient Weight (kg)

Dose (mg/kg)

Frequency

Max single dose (mg, optional)

Concentration (mg/mL, optional)

Growth Percentiles

WHO growth standards (0-2y) / CDC 2000 (2-20y).

Sex

Age (fill any combination)

Gestational Age (weeks)

Weight (kg)

Length/Height (cm)

Head Circumference (cm)

Neonatal Bilirubin

AAP 2022 Clinical Practice Guideline. Determines phototherapy threshold based on gestational age and risk factors.

Neurotoxicity Risk Factors for Phototherapy Threshold (AAP 2022)

Higher Risk (use lower threshold):

Gestational age 35-37 weeks (with other risk factors)
Albumin < 3.0 g/dL
Isoimmune hemolytic disease (ABO, Rh incompatibility)
G6PD deficiency
Asphyxia / significant lethargy
Sepsis
Acidosis (pH < 7.15)
Temperature instability / hypothermia

Lower Risk (use higher threshold):

Gestational age ≥ 38 weeks
No hemolysis
Well-appearing infant
No risk factors above

Source: AAP 2022 Clinical Practice Guideline

Risk Factors for Severe Neonatal Hyperbilirubinemia (Nelson Table 137.1)

Genetic Factors

Gilbert syndrome
Crigler-Najjar syndrome
Alagille syndrome
β-thalassemia
Glucose-6-phosphate dehydrogenase (G6PD) deficiency
Bilirubin glucuronosyltransferase polymorphism
Pyruvate kinase deficiency
Erythrocyte structural defects (hereditary spherocytosis, elliptocytosis)
Galactosemia

Maternal Factors

Family history of severe jaundice, splenectomy, or cholecystectomy
Primiparity
Teenage pregnancy
Diabetes
Rhesus incompatibility
ABO incompatibility
Other blood group isoimmunization
Use of drugs during labor (oxytocin, promethazine, bupivacaine)
Exclusive breastfeeding

Perinatal Factors

Mode of delivery (breech vs vertex, instrumentation)
Birth trauma (cephalohematoma, substantial bruising, extravasation)
Birth asphyxia
Congenital infections (CMV, syphilis)
Sepsis

Neonatal Factors

Male sex
Prematurity or low birthweight and small-for-gestational age
Hypothyroidism
Polycythemia
Hypoglycemia
Low intake of breast milk, dehydration, or weight loss
Breast milk jaundice
Jaundice in the first day of life
Trisomy 21
Infant of diabetic mother
Cephalohematoma, other bruising

Other Risk Factors and Markers

Previous sibling received phototherapy or exchange transfusion
Predischarge TSB or TcB in the high zone
Use of hemolytic agents (naphthalene, menthol-based products) in G6PD-deficient populations
Folate deficiency
Aflatoxins
Hypothermia
Birth outside of a healthcare facility

Modified from Olusanya BO, Kaplan M, Hansen TWR. Neonatal hyperbilirubinaemia: a global perspective. Lancet Child Adolesc Health. 2018;2:610-618. Nelson Textbook of Pediatrics, Table 137.1.

Gestational Age (completed weeks)

AAP 2022 thresholds depend only on completed weeks; days do not change the curve.

Age of Infant (hours)

Total Serum Bilirubin (mg/dL)

Neurotoxicity risk factors

What counts as a neurotoxicity risk factor?

Isoimmune hemolytic disease (positive DAT — ABO or Rh incompatibility)
G6PD deficiency
Other hemolytic disease (congenital or acquired)
Sepsis
Albumin < 3.0 g/dL
Significant clinical instability in the previous 24 hours

Any one qualifies. Per AAP 2022 Box 2. Gestational age < 38w is also a neurotoxicity risk per the guideline but is already accounted for by the per-week threshold curves — do NOT double-count it here.

Normal Vital Signs by Age

Harriet Lane Handbook

Select age group to view normal vital sign ranges. Source: Harriet Lane Handbook.

Age Group

View All Age Groups

Age	HR (bpm)	RR	BP (mmHg)	Temp (C)
Premie	120-170	40-70	55-75/35-45	36.5-37.5
0-3 mo	100-150	35-55	65-85/45-55	36.5-37.5
3-6 mo	90-120	30-45	70-90/50-65	36.5-37.5
6-12 mo	80-120	25-40	80-100/55-65	36.0-37.5
1-3 yr	70-110	20-30	90-105/55-70	36.0-37.5
3-6 yr	65-110	20-25	95-110/60-75	36.0-37.5
6-12 yr	60-95	14-22	100-120/60-75	36.0-37.5
>12 yr	55-85	12-18	110-135/65-85	36.0-37.5

Quick Reference Formulas

Estimated Weight:
1-12mo: (age in mo + 9) / 2
1-5yr: 2 x (age in yr) + 8
6-12yr: 3 x (age in yr) + 7

Min Systolic BP:
1-10yr: 70 + (2 x age in yr)
Hypotension: SBP < 5th %ile

ETT Size:
Uncuffed: (age/4) + 4
Cuffed: (age/4) + 3.5
Depth: ETT size x 3

Maintenance Fluids (4-2-1):
First 10kg: 4 mL/kg/hr
Next 10kg: +2 mL/kg/hr
Each kg above 20: +1 mL/kg/hr

Pediatric Calculators

Blood Pressure Percentile

BMI Percentile

Body Surface Area

Weight-Based Dosing

Growth Percentiles

Neonatal Bilirubin

Normal Vital Signs by Age

Quick Reference Formulas

Resuscitation Medications

Glasgow Coma Scale

Pediatric Equipment Sizing