Blunt Head Injury

Migraine

Head injury is a common reason for visit in family practice and in your local emergency department. Children often have head injuries and so do the elderly, a common mechanism of injury (MOI) for both is due to falls. The peak incidence of head injuries is in males between the age of 15 and 24, and alcohol is often a contributing factor, but head injuries can happen at any age. There are some important nuances when considering the age of your patient, which can help us predict what pathology we might expect to see.

Like any trauma history we often start by learning about the mechanism of injury (MOI). Was there a weapon involved? Were they wearing a helmet or seatbelt? How fast was the vehicle going? Did the airbags deploy? We also want to determine the exact location of the impact as this changes the risk. Was it a frontal impact? Were they struck in the side of the head with a crowbar? I also use the AMPLE history which can be quickly obtained.

Ideally if there was a witness it is good to gather information from them as well. Was there a loss of consciousness?If so for how long? Is there associated amnesia (anterograde, retrograde or mixed). Was there any witnessed seizure activity? I also like to ask about the patients baseline cognitive status and level of function, especially in children and elderly, where the history from the patient might be quite limited. In youth and adults I ask about any impairing substances such as prescription drugs, alcohol or recreational drugs.

In adult and elderly patients it is critical to ask if the patient is taking blood thinners such as Aspirin, Clopidogrel, Warfarin or a Novel Acting Oral Anticoagulant (NOAC) or Direct-Acting Oral Anticoagulants (DOAC).

NOAC/DOAC

  • Dabigatran (Pradaxa®) oral direct thrombin (factor IIa) inhibitor
  • Rivaroxaban (Xarelto®) oral direct factor Xa inhibitors
  • Apixaban (Eliquis®) oral direct factor Xa inhibitors
  • Edoxaban (SavaysaTM) oral direct factor Xa inhibitors

*All have fixed dosing and no routine coagulation monitoring (INR testing)

Elderly patients have a much lower incidence of epidural hematoma than to other age groups, but have a higher incidence of subdural hematomas thought to be the result of decreasing brain mass and increased tension on the bridging veins.

In children it is always important to consider the possibility of non-accidental injury (child abuse). You should be concerned especially if the pattern of injury does not fit with supposed mechanism of injury (MOI) or the severity is beyond what you would anticipate such as a skull fracture when it was reported as a fall from standing height of the child.

Traumatic Brain Injury (TBI) is typically classified as mild, moderate and severe based on the Glasgow Coma Scale (GCS). Mild is typically GCS  14-15. This category can be further subdivided based on your history and physical exam. Lowest risk is GCS 15 without loss of consciousness (LOC), amnesia, vomiting or diffuse headache. Moderate risk is GCS 15 with either LOC, amnesia, vomiting or diffuse headache. Highest risk is when there GCS is 14-15 with evidence of skull fracture or neurological deficits. Moderate is typically GCS 9-13. Severe is when the GCS is <9 and mortality approaches 40% in this group.

For the purpose of this article we will focus on those that have mild TBI (GCS 14-15). Assuming that they have no high risk factors I would typically not obtain neuroimaging. These patients we typically send home with family or friends and instructions about when to return if concerns.

High Risk Features

  • LOC
  • amnesia
  • anticoagulation
  • coagulopathy
  • post-injury vomiting
  • post-injury seizure
  • focal neurologic findings
  • asymmetric pupils
  • distracting injury
  • intoxication
  • large extra cranial hematoma
  • signs of skull fracture

I commonly use this FIFE mnemonic when seeing patients after head injuries. I believe it is really important to elicit the patients ideas and fears as well as their expectations (FIFE). Often patients have an expectation to have a CT or MRI and I try to address there fears and elicit why they feel that imaging is warranted. Knowing information about the Canadian CT Head Rule, PECARN Pediatric Head Injury can be particularly helpful in the setting of blunt trauma.

PECARN Pediatric Head Injury Trauma Algorithm

Canadian CT Head Injury Trauma Rule

 

 

Some Great References:

1. Tintinalli J.E., Kelen G.D., and Strapczynski J.S.  Tintinalli Emergency Medicine, 6th Edition. Section 22 Trauma, 253 Geriatric Trauma

2. Holmes JF, Kuppermann N and PECARN. Guardian availability for children evaluated in the emergency department for blunt head trauma. Acad Emerg Med 2009;16:15-20.

3. Gorelick MH, Atabaki SM, Hoyle JD, Dayan PS, Holmes JF, Holubkov R, Monroe D, Callahan JM, Kuppermann N and PECARN. Interobserver agreement in assessment of clinical variables in children with blunt head trauma. Acad Emerg Med 2008; 15:812-818.

4. Kuppermann N, Holmes JF, Dayan PS, Hoyle JD, Atabaki SM, Holubkov R, Nadel FM, Monroe D, Stanley RM, Borgialli DA, Badawy MK, Schunk JE, Quayle KS, Mahajan P, Lichenstein R, Lillis KA, Tunik MG, Jacobs ES, Callahan JM, Gorelick MH, Glass TF, Lee LK, Bachman MC, Cooper A, Powell EC, Gerardi MJ, Melville KA, Muizelaar JP, Wisner DH, Zuspan SJ, Dean JM, Wooten-Gorges SL.  Identification of children at very low risk of clinically-important brain injuries after head trauma. Lancet 2009:374 1160-70.

5. Lee LK, Dayan PS, Gerardi MJ, Borgialli DA, Badawy MK, Callahan JM, Lillis KA, Stanley RM, Gorelick MH, Dong L, Zuspan SJ, Holmes JF, Kuppermann N, and the Traumatic Brain Injury Working Group for the Pediatric Emergency Care Applied Research Network.  Intracranial hemorrhage after blunt head trauma in children with bleeding disorders.  J Peds June, 2010

6. Nigrovic LE, Schunk JE, Foerster A, Cooper A, Miskin ML, Atabaki SM, Hoyle JD, Dayan PS, Holmes JF, Kuppermann N and the TBI Working Group for the Pediatric Emergency Care Applied Research Network. The effect of observation on head computed tomography (CT) utilization for children after blunt head trauma. Pediatrics 2011;127(6):1067-1073.

7. Holmes JF, Borgialli DA, Nadel FM, Quayle KS, Schamban N, Cooper A, Schunk JE, Miskin ML, Atabaki SM, Hoyle JD, Dayan PS, Kuppermann N, and the TBI Study Group for the PECARN.  Do children with blunt head trauma and normal cranial CT scans require hospitalization for neurological observation? Ann Emerg Med 2011.

8. Nigrovic LE, Lee LK, Hoyle J, Stanley RM, Gorelick MH, Miskin M, Atabaki SM, Dayan PS, Holmes JF, Kuppermann N, and the Traumatic Brain Injury (TBI) Working Group for the Pediatric Emergency Care Applied Research Network.  Prevalence of clinically-important traumatic brain injuries in children with minor blunt head trauma and isolated severe injury mechanisms. Arch Pediatr Adolesc Med 2012 Apr;166(4): 356-361. Epub 2011 Dec 5.

9. Tintinalli J.E., Kelen G.D., and Strapczynski J.S.  Tintinalli Emergency Medicine, 6th Edition. Section 22 Trauma, 255 Head Injury