Pediatrics
Quick reference
The student's pediatric reference: vitals by age, the developmental overview, the growth framework, fever by age in one line, dehydration, newborn basics and the laboratory considerations. Educational reference, not clinical decision support.
Vital signs by age
| Band | Age | HR awake | RR | Hypotension, systolic |
|---|---|---|---|---|
| Newborn | birth to 28 days | 100 to 205 | 30 to 53 | below 60 |
| Infant | 1 to 12 months | 100 to 180 | 30 to 53 | below 70 |
| Toddler | 1 to 3 years | 98 to 140 | 22 to 37 | below 72 (70 + 2 x age) |
| Preschool | 3 to 5 years | 80 to 120 | 20 to 28 | below 76 (70 + 2 x age) |
| School age | 6 to 11 years | 75 to 118 | 18 to 25 | below 82 (70 + 2 x age) |
| Adolescent | 12 to 17 years | 60 to 100 | 12 to 20 | below 90 |
Teaching ranges: AHA PALS 2020 (Fleming 2011 centiles). Saturation: oxygen below 90 percent in bronchiolitis guidance. Fever 38.0 and above; hypothermia below 36.0 (below 36.5 in the newborn, by the WHO definition).
Developmental overview
| Age | Gross motor | Language | Social |
|---|---|---|---|
| 2 months | Lifts the head when prone; moves both arms and legs | Makes sounds other than crying; reacts to loud sounds | Smiles in response to you; calms when spoken to or picked up |
| 4 months | Holds the head steady unsupported; pushes up on the elbows when prone | Coos; makes sounds back when you talk; turns toward your voice | Laughs; looks at you and moves to get attention |
| 6 months | Rolls from tummy to back; leans on hands to support sitting | Squeals; takes turns making sounds; blows raspberries | Knows familiar people; likes to look at self in a mirror; laughs |
| 9 months | Sits without support; gets to a sitting position | Babbles with consonants ('mamamama', 'bababa'); looks when name is called | Shy or clingy with strangers; shows facial expressions; plays peek-a-boo |
| 12 months | Pulls to stand; cruises along furniture; may take first steps | Waves bye-bye; calls a parent 'mama' or 'dada' or a special name; understands 'no' | Plays games like pat-a-cake; looks for hidden objects |
| 18 months | Walks alone; climbs on and off a chair; tries to walk up steps | Three or more words besides names; follows a one-step direction without a gesture | Points to show something interesting; looks at a few pages of a book; copies chores; moves away but checks you are near |
| 2 years | Runs; kicks a ball; walks up a few steps with or without help | Two-word phrases ('more milk'); says at least 50 words; points to pictures in a book; follows two-step directions by about 30 months | Notices when others are hurt or upset; looks at your face to see how to react; plays alongside other children |
| 3 years | Pedals a tricycle; climbs well; stands briefly on one foot | Says first name; talks in conversation with two or more back-and-forth exchanges; asks who, what, where, why; understood by others most of the time | Calms within 10 minutes when a parent leaves; notices other children and joins in play; dresses with help |
| 4 years | Hops on one foot; catches a large ball most of the time | Says sentences of 4 or more words; tells what happened during the day; says some words from a song or story | Pretends to be something else in play; likes to be a helper; changes behaviour based on where they are; comforts others |
| 5 years | Skips; hops repeatedly; buttons some buttons | Tells a story with at least two events; answers simple questions about a story; keeps a conversation going with more than three exchanges | Follows rules or takes turns in games; sings, dances or acts for you; does simple chores |
Developmental red flags
- Any ageLoss of any previously acquired skill (regression)
- Any ageParental concern, which is more sensitive than any screening question
- 3 monthsNo social smile; not fixing and following; persistent fisting
- 6 monthsNot reaching for objects; poor head control; not turning to sound
- 9 monthsNot sitting without support; no babble; not responding to name
- 12 monthsNot pulling to stand; no pointing or gesturing; strong hand preference before 12 to 18 months (suggests weakness of the other side)
- 18 monthsNot walking independently; no single words with meaning; not pointing to show interest; not following a simple instruction
- 2 yearsNo two-word phrases; fewer than 50 words; not running; no pretend play; not following a two-step command by 30 months
- 3 yearsSpeech unintelligible to strangers most of the time; not playing with other children; unable to climb stairs
- 4 yearsNot using sentences; not toilet trained by day (a soft flag with a wide range); cannot draw a circle; unable to hop
Growth framework: WHO Child Growth Standards, birth to 60 months
Boys, kg, birth to 60 months
| Months | 3rd | 15th | 50th | 85th | 97th |
|---|---|---|---|---|---|
| 0 | 2.5 | 2.9 | 3.3 | 3.9 | 4.3 |
| 3 | 5.1 | 5.6 | 6.4 | 7.2 | 7.9 |
| 6 | 6.4 | 7.1 | 7.9 | 8.9 | 9.7 |
| 9 | 7.2 | 7.9 | 8.9 | 10.0 | 10.9 |
| 12 | 7.8 | 8.6 | 9.6 | 10.8 | 11.8 |
| 15 | 8.4 | 9.2 | 10.3 | 11.6 | 12.7 |
| 18 | 8.9 | 9.7 | 10.9 | 12.3 | 13.5 |
| 21 | 9.3 | 10.3 | 11.5 | 13.0 | 14.3 |
| 24 | 9.8 | 10.8 | 12.1 | 13.7 | 15.1 |
| 27 | 10.3 | 11.3 | 12.7 | 14.4 | 15.9 |
| 30 | 10.7 | 11.8 | 13.3 | 15.0 | 16.6 |
| 33 | 11.1 | 12.2 | 13.8 | 15.7 | 17.3 |
| 36 | 11.4 | 12.7 | 14.3 | 16.3 | 18.0 |
| 39 | 11.8 | 13.1 | 14.8 | 16.9 | 18.7 |
| 42 | 12.2 | 13.5 | 15.3 | 17.5 | 19.4 |
| 45 | 12.5 | 13.9 | 15.9 | 18.1 | 20.1 |
| 48 | 12.9 | 14.3 | 16.3 | 18.7 | 20.9 |
| 51 | 13.3 | 14.7 | 16.8 | 19.3 | 21.6 |
| 54 | 13.6 | 15.2 | 17.3 | 19.9 | 22.3 |
| 57 | 13.9 | 15.6 | 17.8 | 20.5 | 23.0 |
| 60 | 14.3 | 16.0 | 18.3 | 21.1 | 23.8 |
Girls, kg, birth to 60 months
| Months | 3rd | 15th | 50th | 85th | 97th |
|---|---|---|---|---|---|
| 0 | 2.4 | 2.8 | 3.2 | 3.7 | 4.2 |
| 3 | 4.6 | 5.1 | 5.8 | 6.7 | 7.4 |
| 6 | 5.8 | 6.4 | 7.3 | 8.3 | 9.2 |
| 9 | 6.6 | 7.3 | 8.2 | 9.3 | 10.4 |
| 12 | 7.1 | 7.9 | 8.9 | 10.2 | 11.3 |
| 15 | 7.7 | 8.5 | 9.6 | 10.9 | 12.2 |
| 18 | 8.2 | 9.0 | 10.2 | 11.7 | 13.0 |
| 21 | 8.7 | 9.6 | 10.9 | 12.4 | 13.8 |
| 24 | 9.2 | 10.1 | 11.5 | 13.1 | 14.6 |
| 27 | 9.6 | 10.7 | 12.1 | 13.8 | 15.4 |
| 30 | 10.1 | 11.2 | 12.7 | 14.5 | 16.2 |
| 33 | 10.5 | 11.7 | 13.3 | 15.2 | 17.0 |
| 36 | 11.0 | 12.2 | 13.9 | 15.9 | 17.8 |
| 39 | 11.4 | 12.6 | 14.4 | 16.6 | 18.6 |
| 42 | 11.8 | 13.1 | 15.0 | 17.3 | 19.5 |
| 45 | 12.1 | 13.5 | 15.5 | 17.9 | 20.3 |
| 48 | 12.5 | 14.0 | 16.1 | 18.6 | 21.1 |
| 51 | 12.9 | 14.4 | 16.6 | 19.3 | 21.9 |
| 54 | 13.2 | 14.8 | 17.2 | 20.0 | 22.8 |
| 57 | 13.6 | 15.3 | 17.7 | 20.7 | 23.6 |
| 60 | 14.0 | 15.7 | 18.2 | 21.3 | 24.4 |
Centile framework: WHO Child Growth Standards 2006 (weight-for-age, length/height-for-age, head circumference-for-age), birth to 60 months, LMS parameters and the 3rd, 15th, 50th, 85th and 97th percentiles from the WHO expanded tables. Teaching use; the plotted children are fictitious and the chart is not for assessing a real child.
Fever by age, in one line each
- Under 28 days: full evaluation (blood, urine, cerebrospinal fluid), empiric antibiotics, admit.
- 29 to 90 days: risk-stratified: inflammatory markers, urinalysis, blood culture; cerebrospinal fluid by risk group.
- 3 months to 3 years: appearance guides; urinalysis for fever without a source; watch the unimmunized.
- Older: find the source on examination; investigate the ill-appearing; Kawasaki at 5 days.
Dehydration, graded clinically
- Minimal (under 3 percent): no signs; continue usual fluids and feeds.
- Mild to moderate (3 to 9 percent): dry membranes, thirst, sunken eyes, refill 2 to 3 seconds, reduced urine, alert or irritable; oral rehydration with ondansetron.
- Severe (over 9 percent): lethargy, weak pulses, refill above 3 seconds, cool extremities, minimal urine; isotonic bolus 20 mL/kg with reassessment, repeat.
- A recent weight is the most objective grade: percentage lost is the deficit.
Newborn basics
- Weight: up to about 7 percent loss, regained by 10 to 14 days; over 10 percent is a feeding assessment.
- Diapers: about one wet per day of life until day 6, then 6 or more.
- Jaundice: under 24 hours is never physiological; beyond 14 days needs a split bilirubin; 7 risk factors on the newborn page.
- Fever or hypothermia in the first month: the full evaluation.
- Glucose: intervene around 2.6 mmol/L in the at-risk infant after the first hours.
Pediatric tracings in the ECG library
Every interval read against the age band. Each tracing runs in the same viewer and calipers as the adult library.
The normal newborn
138 per minute
Normal newborn ECG. Every number here would be abnormal in an adult, and that is the lesson.
Sinus tachycardia in a febrile infant
172 per minute
Sinus tachycardia from fever and respiratory effort. The question is not the ECG; it is whether the perfusion and the mental status are holding.
Supraventricular tachycardia in an infant
244 per minute
Infant SVT. Presented as poor feeding and pallor, not as palpitations, because a 3-month-old cannot say her heart is racing.
Long QT in an adolescent with syncope
58 per minute
Long QT. Syncope with exertion or with a sudden noise, a seizure-like collapse, and a family history of sudden death are the story of a channelopathy, not epilepsy.
Congenital complete heart block
52 per minute
Congenital complete heart block, almost always from maternal anti-Ro/anti-La antibodies damaging the fetal conduction system.
Myocarditis in a school-age child
132 per minute
Persistent tachycardia, low voltage and repolarization change in a child with a viral prodrome and a big liver: myocarditis until an echocardiogram and a troponin say otherwise.
Laboratory considerations in children
Hemoglobin
The physiological nadir at 6 to 9 weeks; iron deficiency peaks in the milk-fed toddler; adolescent girls add menstruation.
White cells
High in the newborn, lymphocyte-predominant through early childhood; a left shift means more than the total.
Creatinine and urea
Muscle mass scales creatinine, so a 'normal' number can be double the child's baseline; use the trend and the urine output.
Sodium and potassium
The speed of sodium correction is the safety issue; neonatal potassium runs higher and hemolysis is common in heel-prick samples.
Glucose and ketones
Small children run out of glycogen fast; ketotic hypoglycemia after fasting is common, non-ketotic hypoglycemia is a metabolic emergency.
Bilirubin
Newborn totals are plotted by the hour; a conjugated fraction is never normal at any age.
Inflammatory markers
C-reactive protein lags; procalcitonin is faster; neither replaces the examination or the cultures in the febrile infant.
Urinalysis
The specimen is the interpretation: a bag sample can rule out, a catheter or clean catch can rule in.
Blood gas
Capillary and venous gases are the norm; carbon dioxide is read for exhaustion, bicarbonate for the anion gap.
Alkaline phosphatase
Runs two to three times the adult limit in growing bones; a 'raised' alkaline phosphatase in a child is usually the growth plate.