This set is about children between one and five. It is the first age group where
the hardest part of the encounter is not the physiology.
The tiers map roughly onto the three phases of a six-year medical program — the science,
then the clinical reasoning, then what you will actually be expected to do with your own hands.
Read the one that fits, and glance at the one above it. If you are on a rural clinical school
placement with us, all three are fair game on a ward round.
Tier one
The science of what has changed since infancy
Phase 1 — the foundational years, and anything called Beginnings, Growth and Development
The airway grows out of some problemsThe obligate nasal breathing of infancy has gone and the occiput is less prominent, so positioning is easier. But adenotonsillar tissue is at its bulkiest between two and six, the larynx is still higher and more anterior than an adult's, and the tissues are softer, so obstruction is easier to produce and harder to relieve.
Poiseuille still governs everythingResistance is inversely proportional to the fourth power of the radius. The airway is bigger than an infant's, so a millimetre of oedema costs less than it did — but it still costs far more than in you. This single equation explains croup, bronchiolitis and why a small child with a swollen airway deteriorates in steps rather than smoothly.
Output is becoming less rate-dependentStroke volume is no longer close to fixed, so the toddler has more ways to compensate than an infant. What has not changed is that the compensation is efficient and silent: they vasoconstrict and speed up, hold a normal blood pressure, and then decompensate abruptly. Hypotension is still a late and pre-terminal sign.
Surface area to mass, still unfavourableThey lose heat faster than you and dehydrate faster than you, and both are worse when they are unwell. Fluid maintenance follows the 4-2-1 rule and resuscitation is 10 mL/kg, not the adult litre.
Glycogen reserve is better but not goodLarger stores than an infant, still small in absolute terms. Any drowsy, fitting or septic small child gets a glucose measured — hypoglycaemia both causes seizures and follows them.
Development is now a clinical variableBy around ten to twelve months they cruise, holding furniture. What a child can physically do determines what injuries are possible, which is why developmental stage is part of the examination and not just the history.
If you take one thing: the physiological gap between this child and an adult
is narrowing, and the behavioural gap is at its widest. That inversion is the whole of this age group.
Likely to be examined as: a short-answer on why airway resistance rises so steeply
with mucosal oedema, or on the physiological basis of compensated shock in a child. A common viva opener
is why does a child's blood pressure stay normal until it doesn't?
Tier two
The encounter, and getting anything out of it
Phase 2 — the clinical years, integrated clinical studies, and the ICE
The history is entirely secondhandThe child cannot give it and will not corroborate it. Ask what has changed rather than whether the parent is worried, and record their words: “not himself” and “he has gone quiet” are clinical findings, not anxiety.
Earn the examinationExamine on the parent's lap. Look before you touch — work of breathing, colour, engagement, whether they track you. Throat and ears last, and only if the finding will change something. A furious child is reassuring; the one who submits without protest has told you something already.
Count for a full minuteSmall children breathe irregularly, so a ten-second count multiplied by six is a guess. Capillary refill, the temperature line moving up the forearm, and conscious state move before the blood pressure does.
Ask the question nobody volunteersCould anything have gone in or gone down? The choking episode was an hour ago, was frightening, resolved, and nobody has thought to mention it. A normal chest film does not exclude an inhaled foreign body — the history is the test.
Look in the nappy, every timeAn incarcerated hernia or a testicular torsion is easy to find and catastrophic to miss, and it is under a garment nobody has opened.
Fever: duration, not heightIn this age group the height of the temperature is a poor guide. How long, how they look between the peaks, and whether there is a source are what matter. Urinary infection is the commonest occult bacterial source, so get urine when there is nothing else to find.
Consider the mechanism against the childDoes the injury match the story, and could a child at this developmental stage have produced it? Bruising to the torso, ear or neck under four, or any bruise in a child not yet cruising, needs a reason.
If you take one thing: almost everything you need is visible from the end of the
cot before you touch them, and almost everything you will be tempted to do first will make the rest harder.
Likely to be examined as: a paediatric long or short case where the marks are in how
you approach the child rather than in the findings. Examiners watch whether you introduce yourself to the
child, whether you examine on the parent, and whether you leave the throat until last.
Tier three
What you will be expected to do
Phase 3 — the final clinical years, the pre-internship term, and your first nights on call
Recognise and escalate; that is the jobYou are not expected to fix the sick child. You are expected to notice early, start oxygen and access, and call. In New South Wales, NETS on 1300 36 2500 would far rather stand a call down than start one an hour late.
Get a real weightEvery drug, every fluid volume, every tube depends on it. An estimate carried through a resuscitation is an error that gets multiplied.
The numbers worth knowing coldFluid 10 mL/kg. Adrenaline 10 microgram/kg. Defibrillation 4 J/kg. Glucose 2 mL/kg of ten per cent. Tracheal tube, cuffed, age divided by four plus three and a half. Check them against your own formulary before you use them, and know where that formulary is.
Croup: do not upset themDexamethasone for every child with croup, however mild. Nebulised adrenaline buys time in the moderate to severe, and wears off in a couple of hours, so they are watched. Do not inspect the throat and do not separate them from the parent.
Wheeze: the spacer, and the silenceSalbutamol by spacer beats a nebuliser in all but the sickest. Add ipratropium early in severe disease. A quiet chest in a tiring child is the emergency — the noise was evidence that air was still moving.
Button battery is a now problemAn oesophageal battery burns within about two hours. Two rings or a halo on the film is a battery rather than a coin. Honey while waiting if over twelve months and within twelve hours, jam if younger, and none of it delays removal.
Analgesia is not optional and does not maskGive it. Withholding opioids in abdominal pain is a dogma that outlived its evidence by decades; if anything the examination improves. Plan analgesia rather than rescuing it.
You are a mandatory reporterEvery clinician in New South Wales is. Suspicion is the threshold, not proof. Document what was said in whose words, without interpreting it, and ask where the other children are tonight.
If you take one thing: at three in the morning your job is to notice early, do the
few simple things well, and call somebody. The commonest error at your stage is not the wrong drug. It is
waiting.
Likely to be examined as: a viva or OSCE station on the collapsed or wheezing child,
or an ingestion scenario. You will be marked on structure and on escalation, not on obscure knowledge —
say out loud what you are doing and when you would call for help.
Over to you
Which tier did you read — and what did I leave out that you needed?
Tell me your year, which tier fitted, and what was missing, too basic or too advanced. If there is a
topic you are struggling with, say that too and I will build the next one around it.