Nursing care
Hydrocephalus nursing care: what to assess and what to do first
Written and reviewed by Dana Whitfield, RN, MSN · 6 min read · Updated September 2026
Short answer
Hydrocephalus causes a bulging fontanelle, a rapidly increasing head circumference and, in later stages, setting-sun eyes from pressure on the upper brainstem. Measure head circumference at every assessment rather than estimating by eye, and monitor for signs of raised intracranial pressure before and after any shunt procedure.
Recognising it at the bedside
In an infant, the fontanelles have not yet closed, so raised intracranial pressure shows first as a fontanelle that is full, tense or bulging even when the baby is calm and upright, rather than only when crying. Head circumference crossing percentiles upward on the growth chart, rather than a single high reading, is the more reliable signal, because head size varies naturally between infants.
As pressure builds, the classic setting-sun sign appears: the eyes deviate downward with the sclera visible above the iris, from pressure on the tectal plate affecting upward gaze. Scalp veins may become distended and prominent, the cry can become high-pitched, and irritability or lethargy alternate unpredictably. In an older child whose fontanelles have closed, the picture shifts toward headache, vomiting, ataxia and papilledema, since the skull can no longer expand to compensate.
Why the classic presentation misleads
A bulging fontanelle can be genuinely subtle in an infant who is feeding well and otherwise looking fine, particularly early on, and it is easy to attribute mild fullness to crying, straining, or normal variation. This is exactly why circumference measurement, plotted against a standardised chart at every visit, matters more than a visual impression of the fontanelle taken in isolation.
Setting-sun eyes are a late finding, not an early warning sign, so waiting for it before acting means intracranial pressure has already been rising for some time. In older infants and children, vomiting can be mistaken for a feeding intolerance or gastroenteritis, and irritability can be attributed to teething or a viral illness, delaying recognition of the underlying pressure. The presentation that finally prompts imaging is often the third or fourth data point, not the first.
Priority nursing actions
Measure head circumference using the same landmark, occipitofrontal, at every shift or visit, and plot it rather than comparing it mentally to yesterday's number. Assess fontanelle tension with the infant upright and calm, not crying, since crying alone can make a normal fontanelle feel full. Monitor level of consciousness, feeding pattern, and cry quality as sensitive early indicators in infants who cannot report headache.
Position the head of the bed at 30 degrees to promote venous drainage unless contraindicated, and support the head and neck carefully during handling given its disproportionate weight relative to the body. Postoperatively, if a ventriculoperitoneal shunt has been placed, position the child flat or on the non-operative side initially per the surgical team's order to avoid overly rapid CSF drainage, and monitor for signs of both shunt malfunction and infection at the incision and along the shunt tract.
Labs and diagnostics to expect
Cranial ultrasound through an open fontanelle is the first-line imaging in infants, since it is quick, avoids radiation and sedation, and can be repeated to track ventricular size over time. Once the fontanelle closes, or when more detail is needed, CT or MRI defines ventricular size and identifies the cause, such as aqueductal stenosis, a mass, or prior intraventricular haemorrhage.
CSF studies, obtained via lumbar puncture or directly from a shunt or reservoir when appropriate, assess for infection and check protein and glucose, particularly important if a shunt infection is suspected. Serial head circumference measurements function as an ongoing diagnostic tool in themselves, plotted alongside imaging findings. Intracranial pressure monitoring may be used in an intensive care setting for children with acute, severe presentations.
Complications and their early signs
Shunt malfunction is the complication to watch for continuously in any child with a ventriculoperitoneal shunt, and it can present as recurrence of the original signs, headache, vomiting, lethargy, or a bulging fontanelle if it recurs before closure, sometimes within days of a previously well-functioning shunt. A change in baseline behaviour or feeding in a shunted infant should be treated as a possible malfunction until ruled out, not dismissed as unrelated.
Shunt infection presents with fever, redness or swelling along the shunt tract, and irritability, and typically develops within the first month or two after placement, though it can occur later. Overdrainage causes slit ventricle syndrome, with symptoms of low CSF pressure such as headache that worsens when upright, while underdrainage produces the same signs as the original untreated hydrocephalus. Long-term developmental delay is a risk correlated with the degree and duration of raised pressure before treatment, underscoring why early measurement and escalation matter.
Teaching that changes outcomes
Parents and caregivers of a shunted child need to recognise the same signs nurses monitor for: a full fontanelle if still open, vomiting, increased sleepiness, irritability, or a change in gait or coordination in an older child, and to seek urgent review rather than waiting to see if it settles. Give them the specific signs, not a vague instruction to watch for problems, since shunt malfunction can progress quickly.
Teach families to bring the child's growth chart and shunt information card to every emergency visit, since a new provider unfamiliar with the child's baseline head circumference or shunt type loses valuable time reconstructing history that should be immediately available. Reinforce that routine childhood activities are generally safe with a shunt in place, but that head injury or a fall warrants prompt medical review given the hardware involved, and that regular follow-up imaging, even when the child seems well, is part of ongoing management rather than optional.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our pediatrics practice questions are the closest set to what this page covers.
Common questions
How is head circumference measured accurately in an infant with suspected hydrocephalus?
Wrap a flexible, non-stretch tape around the largest occipitofrontal circumference, over the most prominent part of the occiput and just above the eyebrows, and take the measurement three times to confirm consistency. Plot the result on a standardised growth chart appropriate to the infant's age and sex rather than relying on a single absolute number.
What does setting-sun sign indicate and is it an early or late finding?
Setting-sun sign, downward deviation of the eyes with visible sclera above the iris, results from pressure on the tectal plate and is a late finding of significantly raised intracranial pressure. It should never be the trigger for first noticing hydrocephalus; head circumference and fontanelle tension should catch it earlier.
How soon after shunt placement can shunt malfunction occur?
Shunt malfunction can occur at any point, including within days of placement, and mechanical obstruction is the most common cause in the first year. Any recurrence of the child's original hydrocephalus symptoms after shunt placement should be treated as a possible malfunction and reported promptly.
What NCLEX-style clues distinguish hydrocephalus from meningitis in an infant?
Both can present with a bulging fontanelle and irritability, but hydrocephalus develops with a progressively enlarging head circumference over time, while meningitis typically presents with fever, nuchal rigidity in older infants, and a more acute, infectious course. Head circumference trending upward across multiple measurements points toward hydrocephalus rather than an acute infectious process.
How should a shunted child be positioned after surgery?
Follow the surgical team's specific order, but children are commonly kept flat or positioned on the non-operative side initially to avoid overly rapid cerebrospinal fluid drainage. Gradual elevation of the head of the bed follows as tolerated, with close monitoring for headache or signs of overdrainage during the transition.