Calgary Neonatal Neuro-Critical Care Program

Neonatal Blood Pressure Centile Calculator

Corrected gestational age with source-specific SBP, DBP, and MAP reference limits or centiles

Step 1

Enter age at birth and today

Gestational age at birth
Postnatal age

Use completed time since birth. For example, 2 days and 6 hours means 54 hours after birth.

Reference model

Select the reference that matches the measurement method and infant. The calculator never joins datasets automatically.

Current blood pressure Optional

Enter one or more measured values to compare them with the selected reference.

How to interpret the result

Reference, not a treatment threshold

These centiles describe a population distribution. They do not define adequate organ perfusion and have not been validated as treatment triggers.

Measurement method matters

Match the selected source to the measurement method and population. Zubrow, van Zadelhoff, Hillman, and Kiss are non-invasive references. Elsayed applies only to invasive UAC measurements in stable preterm infants.

Evidence sources and calculator method

Default Zubrow historical chart: the Philadelphia Neonatal Blood Pressure Study chart uses birth GA during the first 24 hours and corrected postconceptional age afterward. Its separate regression charts are not joined to another source. The plotted lower and upper limits are labelled as historical limits rather than true 5th and 95th centiles. Historical MAP is derived from SBP and DBP.

van Zadelhoff non-invasive model: from 1 to 168 completed postnatal hours, eligible infants use the 2023 non-invasive quantile-regression model. The displayed 5th and 95th centiles are evaluated at normal scores -1.64485 and +1.64485. The model conditions on GA at birth and exact postnatal age.

Elsayed invasive UAC table: this option applies only to stable infants born at 23 to 28 completed weeks with invasive UAC measurements during the first 72 hours. It uses the published day 1, day 2, or day 3 P5, P50, and P95 row for the infant's completed birth-GA week. No hourly or gestational-day interpolation is performed. The internally inconsistent P75 value reported for 24-week day-2 MAP is not used by this calculator.

Hillman weekly mixed-acuity tables: this option uses the published P5, P50, and P95 cells indexed by completed birth-GA week and completed corrected-GA week. It covers birth GA 22 to 40 weeks through corrected GA 40 weeks. No interpolation is performed. The cohort includes NICU, special-care, and normal-newborn measurements, with unequal measurement frequency across gestations.

Kiss stable-neonate tables: this option uses the published P10, P50, and P90 rows for grouped birth gestations on days 1, 3, and 5. It deliberately does not relabel P10/P90 as P5/P95 and does not fill days 2 or 4.

Why the values changed: the previously displayed Dionne table was developed to identify possible hypertension and emphasizes upper centiles. It is retained below as a hypertension source but is not used as the calculator's default normative distribution.

Numerical calculation sources

  1. Zubrow AB, et al. Determinants of blood pressure in infants admitted to neonatal intensive care units: a prospective multicenter study. J Perinatol. 1995;15:470-479.
  2. van Zadelhoff AC, et al. Age-dependent changes in arterial blood pressure in neonates during the first week of life. Br J Anaesth. 2023;130:585-594. doi:10.1016/j.bja.2023.01.024.
  3. Elsayed Y, Ahmed F. Blood pressure normative values in preterm infants during postnatal transition. Pediatr Res. 2024;95:698-704. doi:10.1038/s41390-023-02788-8.
  4. Hillman NH, Williams HL, Petersen RY. Oscillatory blood pressure values in newborn infants: observational data over gestational ages. Neonatology. 2025;122:138-145. doi:10.1159/000542375.
  5. Kiss JK, Gajda A, Mari J, Nemeth J, Bereczki C. Oscillometric arterial blood pressure in haemodynamically stable neonates in the first 2 weeks of life. Pediatr Nephrol. 2023;38:3369-3378. doi:10.1007/s00467-023-05979-x.

Supporting evidence and limitations

  1. Pfurtscheller K, et al. Newborn blood pressure dynamics during immediate postnatal transition: a retrospective analysis. Ital J Pediatr. 2025;51:149. doi:10.1186/s13052-025-02001-y.
  2. Dore R, et al. Neonatal blood pressure by birth weight, gestational age, and postnatal age: a systematic review. Matern Health Neonatol Perinatol. 2024;10:9.
  3. Goldsmith JP, Keels EL, eds. Guidelines for Perinatal Care. 9th ed. American Academy of Pediatrics; 2022.
  4. Dionne JM. Hypertension in the neonate. Hypertension. 2021;77:10-20.
  5. Dionne JM, et al. Method of blood pressure measurement in neonates and infants. J Pediatr. 2020;221:23-31.e5.
  6. Batton B. Neonatal blood pressure and hypertension. Clin Perinatol. 2020;47:29-40.

Older neonates

Hypertension reference calculator

For infants aged 14 days or older. Values are indexed by corrected gestational age.

Gestational age at birth
Postnatal age
Current blood pressure Optional

Enter one or more values to compare them with the 95th and 99th centiles.

Hypertension interpretation

Values at or above the 95th centile are flagged as elevated. Values at or above the 99th centile are flagged as markedly elevated. The table applies after the first two postnatal weeks and covers corrected gestational ages 26 to 44 weeks.

Hypertension evidence sources
  1. Dionne JM. Hypertension in the neonate. Hypertension. 2021;77:10-20.
  2. Dionne JM, et al. Method of blood pressure measurement in neonates and infants. J Pediatr. 2020;221:23-31.e5.
  3. Batton B. Neonatal blood pressure and hypertension. Clin Perinatol. 2020;47:29-40.
  4. Dionne JM, Abitbol CL, Flynn JT. Hypertension in infancy: diagnosis, management and outcome. Pediatr Nephrol. 2012;27:17-32.