Use of CT in minor traumatic brain injury. Lisa Ayoub-Rodriguez, MD Bert Johansson, MD Michael Lee, MD

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1 Use of CT in minor traumatic brain injury Lisa Ayoub-Rodriguez, MD Bert Johansson, MD Michael Lee, MD

2 No financial or other conflicts of interest

3 Epidemiology of traumatic brain injury (TBI) Risks associated with CT Review of clinical decision rules Overview of AAP recommendation regarding children with head injury

4 Pediatric head injury is extremely common A large majority of children have minor injuries A small number, even among well appearing children will have more serious injuries with potential for deterioration and significant sequelae Important to identify children at higher risk of developing intracranial complications Clinical symptoms are neither completely sensitive or specific CT accurately identifies ICI requiring intervention but exposes developing brains to ionizing radiation with the associated risks

5 TBI is the leading cause of death and disability in children worldwide TBI results in about 7,400 deaths, 60,000 hospital admissions and over 600,000 ED visits each year About 50% of children assessed for head trauma undergo CT CT use has more than doubled between

6 Children with minor head injury with GCS are most frequently assessed They account for 40-60% of children who underwent CT Less than 10% of CT scans show traumatic brain injuries Injuries needing neurosurgery are very uncommon in children with GCS of 14-15

7 No single definition is universally accepted Defines as a "traumatically induced physiological disruption of brain function, as manifested by 1 of the following Any period of LOC Any loss of memory for events immediately before or after the accident Any alteration in mental state at the time of the accident Focal neurological deficits that may or may not be transient, but where the severity of the injury does not exceed the following: Post-traumatic amnesia not greater than 24 hours After 30 minutes, an initial GCS of LOC of approximately 30 minutes or less

8 Second Impact Syndrome Diffuse cerebral swelling, herniation and death due to subsequent head injury Unknown overall incidence, thought to be very rare ICH Epidural hematoma Subdural hematoma SAH Cerebral contusions IVH Delayed ICH after uncomplicated minor head injuries

9 In a 8 year retrospective cohort study of children <14 years of age, cases of uncomplicated minor head injuries and delayed diagnosis of intracranial hemorrhage were identified 17,692 children were evaluated Incidence of delayed diagnosis with Deterioration in level of consciousness = 0.14 cases per 100,000 children/year No deterioration in level of consciousness = 0.57 cases per 100,000 children/year

10 Reasons to use CT Preventable morbidity/mortality due to unrecognized TBIs Preverbal children with difficult evaluation When indicated the benefit of CT greatly outweighs risk However associated with risks as well as costs

11 Of the approximately 300,000 children evaluated with CT, fewer than 10% have severe TBI Drawbacks include availability, risks of sedation, costs Includes risk of lethal malignancy due to ionizing radiation

12 Estimated rate of lethal malignancies from CT is between 1 in 1000 and 1 in 5000 from head CT Risk increases as age decreases In the US, of approximately 600,000 CT scans annually performed in children < 15 years, a rough estimate is that 500 of these individuals might ultimately die from cancer attributable to CT radiation

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14 The clinician's goal is to identify patients who develop clinically important ICI to prevent deterioration and secondary brain injury while limiting unnecessary radiographic imaging Unfortunately, defining sensitive and specific clinical predictors have been challenging Many patients with ICI may not present with symptoms or functional derangements Many with normal neurological exam who exhibit common symptoms (HA, vomiting) may harbor ICI

15 Incidence of ICI is ~5% in children who have GCS 14-15, nonfocal neurologic examination and no obvious skull fracture Due to variability of clinical predictors in identifying ICI and the concern for missing ICI, clinicians may adopt a liberal approach to the use of CT scans Clinical decision rules help determine which children are at highest risk and provide a useful clinical framework CDR incorporates 3 or more variables from history, PE or simple tests into a tool that helps clinicians make diagnostic or therapeutic decisions at the bedside

16 Involved > 42,000 patients younger than 18 years with head trauma in 25 emergency departments in US Focused on children with minor head injury and GCS Described need for separate CDR for different age groups as younger children are more difficult to assess and more sensitive to radiation Aim was to derive and validate prediction rules for citbi to identify children at very low risk of citbi after blunt head trauma for whom CT might be unnecessary

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18 Involved 3866 patients with blunt head trauma with GCS who presented to 10 Emergency depts in Canada Decision based on 4 high risk factors and 3 medium risk factors for neurological intervention Focused on children with minor head injuries and GCS Aim was to prospectively derive an accurate and reliable clinical decision rule for the use of CT in children with minor head injury

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20 Involved 22,772 children < 16 years old who presented with head injury in 10 EDs in England Included children with all severity of HI in whom there is a low prevalence of life threatening complications Aim was to conduct a prospective multicenter diagnostic cohort study to provide a rule for selection of high-risk children with head injury for CT scanning

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22 Clinically significant ICI/Brain injury CATCH Sensitivity 98.1%, Specificity 50.1%, NPV 99.8%, PPV 7.8% CHALICE Sensitivity 97.6, Specificity 87.3%, NPV 99.9%, PPV 5.4% PECARN <2 Sensitivity 98.6%, Specificity 53.7%, NPV 99.9%, PPV 1.8% PECARN >2 Sensitivity 96.7%, Specificity 58.5%, NPV 99.95%, PPV 2%

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24 Decision rules are developed to guide the clinician in a more thoughtful approach to CT as to avoid overuse while still identifying important ICI No rules eliminate all risk but provide framework for risk assignment AAP recommendation is based on compilation of multicenter studies as well as recent reviews

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26 Recommends observation in the clinic, office, emergency department or home under the care of a competent observer as a primary management strategy If on examination the patient s condition appears normal, no additional tests are needed and the child can be safely discharged to the care of a responsible caregiver

27 In children who are neurologically normal after minor closed head injury with loss of consciousness, patient observation was an acceptable management option If the observer seems unable to follow or comply with the instructions for home observation, observation under the supervision of a health care practitioner is to be considered If the child s neurologic condition worsens during observation, a through neurological examination is to be performed, along with immediate cranial CT after the patient s condition is stabilized

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31 Observation before obtaining CT was associated with significantly lower rate of overall CT use with no increase in the rate of significant injuries Furthermore, ED observation time was associated with a time-dependent reduction in cranial CT rate with no delay in the diagnosis of a significant traumatic brain injury Median time between head injury and CT decision-making was approximately 4 hours for observed patients Every hour of observation reduced the rate of CT use by 70% on average

32 Threshold to evaluate should be lower in specific cases Second impact syndrome Important concern for re-injured concussive patient NAT CT warranted to evaluate for acute as well as old ICI Cognitive impairment Poor verbal skills and at higher risk of NAT Imaging in children with hemophilia is controversial No neuroimaging guidelines and limited clinical evidence to direct care Use of CT in children without signs/symptoms of ICH very common Divergent opinion

33 Pediatric head injury is very common and usually minor but can result in serious morbidity Multiple clinical decision rules exist to provide framework and help identify children at high risk for ICI Based on strong research evidence, CT scan remains a highly useful adjunct in evaluation of head injury but should be used selectively for children at higher risk for ICI Observation can be used selectively and any concerns during the observation period should prompt CT imaging

34 Bey T, Ostick B. Second Impact Syndrome. Western Journal of Emergency Medicine. 2009;10:6-10. Brenner D, Elliston C, Hall E, Berdon W. Estimated Risks of Radiation- Induced Fatal Cancer from Pediatric CT. AJR 2001;176: Osmond M, Klassen T, Wells G, et.al. CATCH: a clinical decision rule for the use of computed tomography in children with minor head injury. CMAJ 2010;182(4): Lyttle M, Crowe L, Oakley E, et al. Comparing CATCH, CHALICE and PECARN clinical decision rules for paediatric head injuries. Emerg Med J 2012;29: Dunning J, Daly JP, Lomas J-P, et al. Derivation of the children s head injury algorithm for the prediction of important clinical events decision rule for head injury in children. Arch Dis Child 2006;91: Schonfeld D, Fitz B, Nigrovic L. Effect of the Duration of Emergency Department Observation on Computed Tomography Use in Children With Minor Blunt Head Trauma. Ann Emerg Med 2013; S (13)

35 Kupperman N, Holmes J, Dayan P, et al. Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet 2009; 374: Lee B, Newberg A. Neuroimaging in Traumatic Brain Imaging. NeuroRx 2005; 2: Kirkwood M, Yeates K, Taylor H, et al. Management of Pediatric Mild Traumatic Brain Injury: A Neuropsychological Review from Injury Through Recovery. Clin Neuropsychol 2008; 22(5): Schunk J, Schutzmann S. Pediatric Head Injury. Pediatrics in Review 2012;33; Lumba A, Schnadower D, Joseph MM. Evidence-Based Assessment and Management of Pediatric Mild Traumatic Brain Injury. Pediatric Emergency Medicine Practice 2011; 8(11):1-20 Committee on Quality Improvement, AAP. The management of Minor Closed Head Injury in Children. Pediatrics 1999;104;1407