Clinical tool
Pediatric NIH Stroke Scale
A structured way of describing how neurologically affected a child is during an acute stroke and of tracking what happens next.
The most important thing to remember
PedNIHSS quantifies neurological deficit. It does not diagnose stroke, identify the occluded vessel, determine infarct size, or independently decide whether a child should receive thrombolysis or thrombectomy.
01
What is the PedNIHSS?
The Pediatric NIH Stroke Scale (PedNIHSS) is a paediatric adaptation of the adult NIH Stroke Scale used to quantify the severity of neurological impairment associated with stroke.
It was developed because simply applying the adult NIHSS to children is problematic: language, comprehension and the ability to follow commands change substantially with age and development.
The PedNIHSS therefore preserves the major neurological domains assessed by the adult NIHSS while adapting parts of the examination for children.
02
What are we actually testing?
PedNIHSS converts a structured neurological examination into a numerical score. The domains sample several different cortical, motor, sensory and brainstem functions.
Total PedNIHSS
Higher scores indicate greater neurological impairment.
The total score should always be interpreted alongside the clinical examination and the child's age and developmental abilities.
03
So what makes it paediatric?
Adult NIHSS
Assumes adult language, comprehension and ability to perform standard neurological commands.
PedNIHSS
Uses developmentally appropriate questions, commands and assessment techniques while preserving the structure of the NIHSS.
For example, rather than relying entirely on adult orientation questions, assessment can be adapted to the child's developmental level.
Visual field and language assessment may also need modification according to age, developmental ability and cooperation.
04
What does the number mean?
At its simplest, a higher PedNIHSS means that more neurological deficit has been detected by the structured examination.
Be careful with severity categories
NIHSS scores are often divided into categories such as minor, moderate and severe stroke. These categories largely derive from adult stroke literature and should not automatically be treated as validated paediatric treatment thresholds.
Case connection
What does a PedNIHSS of 26 tell us?
26
PedNIHSS
This child has a profound measurable neurological deficit. That immediately communicates the seriousness of the presentation to everyone involved.
But the number alone does not tell us the mechanism. A score of 26 cannot distinguish thrombus from dissection, identify a large-vessel occlusion, demonstrate viable penumbra or tell us whether reperfusion therapy is appropriate.
Those decisions require the PedNIHSS to be integrated with the clinical examination, time from symptom onset, brain imaging, vascular imaging, contraindications and specialist neurovascular discussion.
05
Does a higher PedNIHSS mean the child should receive thrombolysis?
No. PedNIHSS is fundamentally a severity scale, not a treatment algorithm.
A high score can support the clinical impression that a stroke is severe and disabling, but it does not establish whether there is salvageable brain tissue, whether a treatable arterial occlusion is present, or whether thrombolysis can be given safely.
Conversely, a relatively low PedNIHSS does not necessarily mean that reperfusion is unimportant. A child may have a clinically disabling deficit that produces relatively few points on the scale.
Clinical
Is the deficit disabling?
Imaging
What vessel and brain tissue are involved?
Time & risk
Is reperfusion appropriate and safe?
PedNIHSS contributes to the decision.
It does not make the decision.
06
Where does PedNIHSS fit into UK stroke management?
The RCPCH childhood stroke guideline incorporates PedNIHSS into the neurological assessment of a child with suspected acute stroke.
The 2017 pathway also incorporated PedNIHSS into its criteria for considering intravenous thrombolysis. One of the listed criteria was a PedNIHSS score of 4–24, alongside age, timing, imaging findings and absence of contraindications.
Which creates an interesting problem...
What happens when the child has an unequivocally disabling stroke but the PedNIHSS is 26?
The score describes severity. It should not replace expert clinical and imaging-based decision-making.
07
One number matters. The trend may matter more.
PedNIHSS also gives teams a common language for serial neurological assessment.
26
Presentation
?
Post-treatment
?
During retrieval
?
PICU
A changing score can help communicate neurological improvement or deterioration between ED, stroke, retrieval and PICU teams. However, new neurological deterioration requires assessment in its own right rather than simply documenting a new score.
08
What can PedNIHSS miss?
Like the adult NIHSS, the score is not a complete neurological examination.
Age, developmental stage, cooperation, language and pre-existing neurological impairment can complicate interpretation in children.
A relatively low score should therefore never override a convincing history, a disabling focal deficit or concerning neurovascular imaging.
PedNIHSS tells you how much deficit you can measure.
It does not tell you how much brain is at risk.
References
Further reading
1. Ichord RN, Bastian R, Abraham L, et al. Interrater reliability of the Pediatric National Institutes of Health Stroke Scale (PedNIHSS) in a multicenter study. Stroke. 2011;42(3):613–617.
2. Beslow LA, Kasner SE, Smith SE, et al. Concurrent validity and reliability of retrospective scoring of the Pediatric National Institutes of Health Stroke Scale. Stroke. 2012;43(2):341–345.
3. Royal College of Paediatrics and Child Health. Stroke in childhood: clinical guideline for diagnosis, management and rehabilitation. London: RCPCH; 2017.
4. Ferriero DM, Fullerton HJ, Bernard TJ, et al. Management of stroke in neonates and children: a scientific statement from the American Heart Association/American Stroke Association. Stroke. 2019;50:e51–e96.