We have a clear algorithm for when to CT children who present with head injuries immediately after the injury. But, when children present more than 24 hours after an injury, we aren’t really sure what is best practice. This paper, by the PREDICT group, looks at the rates of traumatic brain injury in this patient group.
Borland M, Dalziel SR, Phillips N, Lyttle M, Bressan S, Oakley E, Hearps SJC, Kochar A, Furyk J, Cheek J, Neutze J, Gilhotra Y, Dalton S, Babl F. Delayed Presentations to Emergency Departments of Children With Head Injury: A PREDICT Study, Annals of Emergency Medicine, DOI: https://doi.org/10.1016/j.annemergmed.2018.11.035
Why is this study needed?
We have a range of decision rules to help guide us for children presenting immediately after a head injury. PECARN and CATCH clinical decision rules specifically exclude children who present with a head injury more than 24 hours after the injury. CHALICE doesn’t specifically exclude this group, but there is no published data on this group of patients.
What we worry about is missing a traumatic brain injury, and in particular, one that will need surgical intervention. If a child presents after the initial 24 hours, are they more likely to have a traumatic brain injury, and should we, therefore, have a lower threshold to CT scan these patients?
This is a really common dilemma in Paediatric Emergency. In my own experience, most people have a lower threshold for scanning children presenting late with head injury concerns because of the lack of guidance and evidence in this group.
The authors’ aim is to look at the prevalence of traumatic brain injury in this group and to identify any factors in these patients that would make a traumatic brain injury more likely.
Who were the patients?
This was a secondary analysis of an existing cohort – the Australian Paediatric Head Injury Study cohort. This was children with a head injury who presented to one of ten paediatric EDs in Australia/New Zealand over a 3.5-year period.
For this secondary analysis, the cohort was split into those presenting within 24 hours and those presenting later than 24 hours after the head injury. 5% of the cohort presented >24 hours after the injury.
Children were excluded if they had GCS<14 and were also excluded for representations of the same injury.
The original APHIRST cohort included 20,137 head injury presentations.
352 were excluded due to GSC<14, and 20 were excluded due to unknown time to presentation.
Of the 19,765 left, 981 children presented >24 hours after the injury.
Definitions
Traumatic brain injury on CT (TBI) – intracranial haemorrhage or contusion, cerebral oedema, traumatic infarction, diffuse axonal injury, shearing injury, sigmoid sinus thrombosis, signs of brain herniation, midline shift, diastasis of the skull, pneumocephalus, and depressed skull fracture.
Clinically important traumatic brain injury (cTBI) – death, intubation >24 hours, neurosurgery, or a traumatic brain injury-related admission to hospital of two or more nights.
What were the authors looking at?
The paper examined any associations between a delay in presentation and the mechanism of injury.
It also looked at the injury characteristics and demographics for patients presenting within and after 24 hours of the injury.
Who presented more than 24 hours after a head injury?
Those presenting >24 hours after the injury were significantly more likely to have had a non-frontal scalp haematoma, headache, vomiting, and assault with non-accidental injury concerns.
Loss of consciousness and amnesia were more likely to present within 24 hours of the injury.
Were the late presentations more likely to have a head CT and a brain injury than those presenting within 24 hours?
203 of the 981 patients had a head CT in the late group. This is 20.6% compared to 7.9% in the early presentations.
37 of these children had a TBI on head CT. This is 3.8% compared to 1.2% in the early presentations group. The most common injuries were a depressed skull fracture, intracranial haemorrhage, or contusions.
Eight children had a cTBI (0.8% – which is the same as in the early group) and two required neurosurgical intervention (also not significantly higher than in the early group).
Who were the eight children with clinically important traumatic brain injuries?
The children ranged from six months to 15 years.
- Five of them had a low-level fall (<1 m) – one of these required neurosurgical intervention
- One was struck by a high speed object
- One sustained a blunt injury with a bat during sport – required neurosurgical intervention
- One fell out of bed more than two days earlier
Of note in the late group…
No children with amnesia had a traumatic brain injury on head CT
Suspicion of a depressed skull fracture and a non-frontal scalp haematoma were significantly associated with a cTBI
No children with loss of consciousness had a cTBI
What can we take from this?
There may be many reasons why our scanning rate in delayed head injury presentations is so much higher – including the lack of previously existing evidence, and our clinical concern that a TBI is more likely if the symptoms are persisting.
The authors conclude that presenting >24 hours after the injury (with a GSC>14), significantly increases the risk of a TBI. Suspicion of depressed skull fracture or a non-frontal scalp haematoma increase the risk of TBI and cTBI in this group.
Commentary from Damian Roland:
This is a useful sub-analysis of a very good research data set prepared by the PREDICT group which has good face validity and is likely to be externally reproducible in other developed nations.
The question I ask myself when reviewing head injury patients with a ‘delayed’ presentation is ‘why are you delayed?’. The sheer size of this data set is testament to the fact that lots of children present to Emergency Departments because of parental concern following a fall or blunt trauma. If a parent chooses not to present initially it’s usually because they thought the injury was not that significant (not a very high bar to reach usually!) and symptoms have evolved or perhaps the initial circumstances weren’t clear or un-witnessed. For the former case this ‘evolution’ of disease is (not surprisingly) significant. The ‘delayed’ group more likely to demonstrate relevant pathology because the symptoms that pathology were producing were becoming more apparent. For the latter “historical’ muddying is either sinister (note the relationship with non-accidental injury concerns) or perhaps critical information which may have resulted in earlier attendance has been missed.
It is important to note that while the post 24 hour group demonstrated increased risks for many features and outcomes, the absolute numbers are still low. Just because you present 24 hours down the line doesn’t mean do a CT. Just think that bit more carefully than if the child had presented straight after the injury. As this same group have also recently shown, our individual decision making capacity is probably just as good as any rule so we can still trust our own clinical judgement
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