Bedside Snapshot
- Use It When
- Any child or newborn lab result: read the value against the age-specific interval printed by the lab, not an adult range.
- Key Numbers
- Hgb anemia cutoffs: <105 g/L at 6–23 mo; <110 at 24–59 mo; <115 at 5–11 yr
- Neonatal glucose target: above 50 mg/dL under 48 h, then above 60
- Bilirubin: read at the exact hour of age
- Formulas
- Bedside Schwartz eGFR (steady-state creatinine): 0.413 × height (cm) ÷ serum creatinine (mg/dL) = mL/min/1.73 m²
- Action Thresholds
- Jaundice with pale stools: direct bilirubin now
- Bilirubin at the phototherapy threshold for age: neonatal review per protocol
- Watch Out
- Adult cutoffs give false reassurance in children. A normal adult number can hide anemia or acidosis in a young child.
Overview & Pediatric Differences
An adult interval will call a sick child normal. Hemoglobin, creatinine, bilirubin and blood gas values all shift with age. Some of them shift in the first days of life. Adult intervals do not apply to them.
Why Kids Are Different
- Hemoglobin: the normal range shifts as the child grows. The anemia cutoff is set by age band.
- Bilirubin: newborn bilirubin rises. Read it against age in hours, never against one adult cutoff.
- Blood gases: adult pH and PaCO₂ bands do not describe a neonate or infant. Cord and early values need neonatal intervals.
- Creatinine: the pediatric interval depends on age and muscle mass. The same number means different things at different ages.
Where a number was not verified, the page gives the method instead. Every number on this page is cited to a primary source in its section. For the reference itself, go with the age-specific interval printed by the lab that ran the test.
Hemoglobin & Hematocrit by Age
Children get age-banded anemia cutoffs. The table lists the fifth centiles of healthy reference samples from the 2024 Lancet Haematology analysis, built to inform WHO and clinical guidelines. It also lists the rounded anemia cutoffs this page uses.
| Age group | Fifth centile (g/L) | Anemia cutoff (g/L) |
|---|---|---|
| 6–23 months | 104.4 | <105 |
| 24–59 months | 110.2 | <110 |
| 5–11 years | 114.4 | <115 |
| 12–17 years, female | 122.2 | Sex-specific; see Adolescents |
| 12–17 years, male | 128.2 | Sex-specific; see Adolescents |
These are population anemia definitions, not transfusion thresholds. They do not apply to neonates. The analysis covers ages 6 months to 65 years. This page does not adjust the cutoffs for altitude or smoking. For neonatal hemoglobin and hematocrit, and for any transfusion decision, use the performing laboratory's interval. Hematocrit intervals are not given on this page.
Glucose in Neonates & Children
Low glucose in a neonate or child is a lab-triggered emergency. The 2015 Pediatric Endocrine Society recommendations set the treatment targets below. The local neonatal or pediatric protocol and medical direction set the dextrose concentration and volume.
| Patient | Target |
|---|---|
| High-risk neonate, under 48 hours | Above 50 mg/dL |
| High-risk neonate, over 48 hours | Above 60 mg/dL |
| Confirmed or persistent hypoglycemia disorder | Above 70 mg/dL |
- Symptoms: neurogenic and neuroglycopenic symptoms usually start as glucose falls to about 50–70 mg/dL. In older children and adults, cognition is documented as impaired below 50 mg/dL.
- Sample artifact: whole-blood glucose reads about 15% lower than plasma glucose. A delayed sample can lose up to 6 mg/dL per hour, because red cells keep using glucose. Confirm a critical value on a prompt lab sample when time allows.
- Older children: adult glucose values live on the adult glucose page. Pediatric dosing rules live on the weight-based dosing page.
Bilirubin: Inputs for the AAP 2022 Figures
The AAP 2022 guideline for newborns of 35 or more weeks of gestation plots total serum bilirubin against postnatal age in hours. Gestational age and neurotoxicity risk factors set the phototherapy and exchange thresholds. The guideline also lays out an escalation-of-care pathway. This page does not transcribe the threshold values. Read them off the guideline figures at the infant's exact hour of age.
| Input | Why it matters | Action |
|---|---|---|
| Exact age in hours | The nomogram is read at a specific hour of life | Record the hour of birth and the hour of the draw |
| Gestational age | Sets the phototherapy threshold | Confirm from the birth record |
| Neurotoxicity risk factors | Lower the threshold for treatment | Check the guideline list |
| Transcutaneous reading | A screen only; device accuracy varies | Confirm a high value with a serum bilirubin |
Blood Gas Basics by Age
A neonate or infant does not fit the adult pH and PaCO₂ bands. Take the age-specific arterial or venous band from the lab that ran the sample. First-day and cord values sit on the neonatal interval.
| Patient | Sample | Interval to use |
|---|---|---|
| Cord or first hours | Cord arterial or early arterial | Neonatal interval from the lab |
| Neonate and young infant | Arterial or capillary | Neonatal or infant interval from the lab |
| Child | Arterial or venous | Pediatric interval from the lab |
No pH, PaCO₂ or base-deficit bands appear on this page. Lab and sample type both change the neonatal and infant interval. Match the printed band to this patient's age and sample type.
Creatinine & Kidney Function by Age
Read serum creatinine against the pediatric interval for the child's age. An adult-normal value can signal kidney injury in a small child. A rising trend matters more than any single value.
- Use the trend: set it against an earlier value from the same patient.
- Bedside Schwartz estimate: eGFR (mL/min/1.73 m²) = 0.413 × height (cm) ÷ serum creatinine (mg/dL). It assumes steady-state creatinine. It is not valid during acute kidney injury or rapid change. The constant did not fit well in one Japanese pediatric cohort. Treat the result as approximate.
- Dose drugs with the weight and kidney function: follow the medication page and pharmacy.
Adult equations are not used for children. This page gives no age-banded creatinine intervals. Use the laboratory's pediatric interval.
Interpretation & Action Thresholds
| Finding | Meaning | Action |
|---|---|---|
| Jaundice with pale stools | Cholestatic jaundice is always pathologic and needs early evaluation | Direct bilirubin now; urgent referral |
| Bilirubin at or approaching the phototherapy threshold for age | Hour-specific bilirubin near the AAP 2022 line | Neonatal review per protocol |
| Hemoglobin below the age cutoff | Anemia for that age band | Confirm with a repeat sample; evaluate per protocol |
Pitfalls & Safety Checks
| Pitfall | Consequence | Prevention |
|---|---|---|
| Adult interval used for a child | Missed anemia or acidosis | Read the age-specific interval printed on the report |
| Bilirubin without age in hours | Cannot place the value on the nomogram | Record the hour of age with every sample |
| Transcutaneous value treated as final | Treatment decision on a screen | Confirm with serum bilirubin |
Special Populations
Neonates and Young Infants
- Use the performing laboratory's neonatal intervals for hemoglobin, bilirubin and blood gases.
- The AAP 2022 bilirubin guideline covers infants of 35 or more weeks of gestation. Preterm infants need NICU-specific thresholds.
- Heel-stick and capillary samples can read differently from venous ones. Hemolysis can falsely raise potassium. Confirm a surprising value with a venous or lab sample.
- Point-of-care glucose reads lower than plasma glucose. A delayed sample reads lower still. Confirm a low value with a lab sample when time allows.
Adolescents
- Hemoglobin cutoffs diverge by sex in adolescence: the fifth centile is 122.2 g/L for females and 128.2 g/L for males aged 12–17 years.
- Adult intervals for other tests may apply by age and sex. Confirm with the lab.
Neonatal Resuscitation
- Newborn resuscitation and assessment follow the 2025 AHA/AAP guideline, Part 5.
Prehospital & Transport Considerations
- EMS: record the exact age in hours for any newborn with jaundice; send the age with the handoff.
- ED/ICU: send blood gas and hemoglobin samples with the child's age and weight.
- Transport: follow local protocols and medical direction for any point-of-care test.
Clinical Pearls
References
- Kemper AR, Newman TB, Slaughter JL, et al. Clinical Practice Guideline Revision: Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation. Pediatrics. 2022;150(3):e2022058859. https://doi.org/10.1542/peds.2022-058859
- Thornton PS, Stanley CA, De Leon DD, et al. Recommendations from the Pediatric Endocrine Society for Evaluation and Management of Persistent Hypoglycemia in Neonates, Infants, and Children. J Pediatr. 2015;167(2):238–245. https://doi.org/10.1016/j.jpeds.2015.03.057
- Braat S, Fielding KL, Han J, et al. Haemoglobin thresholds to define anaemia from age 6 months to 65 years: estimates from international data sources. Lancet Haematology. 2024;11(4):e253–e264. https://doi.org/10.1016/S2352-3026(24)00030-9
- Fawaz R, Baumann U, Ekong U, et al. Guideline for the Evaluation of Cholestatic Jaundice in Infants: Joint Recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition. J Pediatr Gastroenterol Nutr. 2017;64(1):154–168. https://doi.org/10.1097/MPG.0000000000001334
- Uemura O, Honda M, Matsuyama T, et al. Is the new Schwartz equation derived from serum creatinine and body length suitable for evaluation of renal function in Japanese children? Eur J Pediatr. 2012;171(9):1401–1404. https://doi.org/10.1007/s00431-012-1772-y
- American Heart Association and American Academy of Pediatrics. Part 5: Neonatal Resuscitation: 2025 American Heart Association and American Academy of Pediatrics Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2025;152(16 suppl 2). https://doi.org/10.1161/CIR.0000000000001367
- World Health Organization. Guideline on haemoglobin cutoffs to define anaemia in individuals and populations. Geneva: WHO; 2024 (published 5 March 2024). ISBN 978-92-4-008854-2. https://www.who.int/publications/i/item/9789240088542
Medical Disclaimer
- For Educational Purposes Only: This content is intended for educational reference and should not be used for clinical decision-making.
- Not a Substitute for Professional Judgment: Always consult your local protocols, institutional guidelines, and supervising physicians.
- Verify Before Acting: Users are responsible for verifying information through authoritative sources before any clinical application.