Head Trauma: Surgical Management



Head Trauma: Surgical Management


Sandrine de Ribaupierre MD, FRCSC

Peter Dirks MD, PhD, FRCSC



INTRODUCTION



  • Pediatric head injury incidence is 2 per 1,000 under 15 years of age, and 3.4 per 1,000 for ages 15 and over.


  • Neurologic injuries account for 18% of all pediatric injuries and 23% of traumatic deaths.1


  • Closed head trauma has a fatality risk of 0.5 per 1,000.2


  • Eight percent to nine percent of patients with a mild head injury (Glasgow Coma Scale 13-15) lacking neurologic symptoms will have an abnormal CT scan, and 1% to 4% will require a neurosurgical intervention.3,4


  • Children have fewer mass lesions than adults, but more skull fractures.


  • Severity of head injury is typically assessed with the Glasgow Coma Scale (GCS),



    • Mild head injury: GCS 13-15.



      • No or brief loss of consciousness (LOC).


    • Moderate head injury: GCS 9-12.



      • LOC from a few minutes to hours, confusion can last a few days.


    • Severe head injury: GCS ≤8.



      • Coma is defined by a profound state of unconsciousness.


      • Comatose patient fails to respond normally to voice, pain or light, does not have sleep-wake cycles, and does not take voluntary actions.


INITIAL MANAGEMENT



  • Use ATLS protocol for initial evaluation of pediatric head injuries.



    • DO NOT rush to CT with a unilateral or bilateral mydriasis without completing the ABCs.


    • Hypoxia, hypoglycemia, and hypotension are associated with much worse outcome following severe head injury.


  • Establish a secure airway.



    • Prevent secondary brain injuries by ensuring there are no breathing or circulatory problems in a head-injured child.


  • If there is evidence of intracranial hypertension/herniation, give mannitol (0.5-1 g/kg) or hypertonic saline (3% NaCl at 3 mL/kg).


  • Hyperventilation is not routinely recommended, unless clinical signs of acute herniation.


  • Cervical spine trauma can be associated with significant head injuries.


EVALUATION


History



  • Determine mechanism of injury as per patient, witness, parents, paramedics:



    • Acceleration/deceleration mechanism (MVA, falls).


    • Blunt trauma (falls, blows).


    • Crush injury.



    • Penetrating injury (falls, blows, toys, missile).


    • Children can have bizarre mechanisms of accidental injury.


  • Determine if loss of consciousness occurred and its duration.



    • Did patient talk at any time?


    • Does patient recall the accident?


  • Determine if there has been a fluctuating level of consciousness or progressive deterioration/amelioration.


  • Determine amount of time elapsed from time of injury.


  • Did a seizure occur following the trauma?


  • Did hypoxia or hypotension occur at any time?


  • How much bleeding resulted from the head injury (scalp, sinus, carotid, ear, nose)?


  • Any other injuries?


Physical Exam



  • Assess pupil size and reactivity to light.



    • Should occur during primary survey with the GCS.


  • Check for local signs of trauma, such as contusion/laceration/skin mark above the clavicles.


  • Use the GCS to record level of consciousness and fluctuations in time (Table 6-1).



    • Motor assessment is most reliable indicator in infant and younger children (unless associated spinal cord injury).


    • GCS may be unreliable in young children because different scales can make assessment difficult.


    • Document each of 3 scores (eyes, motor, verbal) leading to final GCS.


    • GCS score has not been fully validated in pediatric patients but it is important to document initial GCS and follow trends over time.5


  • Assess for:



    • Motor deficits.


    • Sensory deficits.


    • Change in reflexes.


  • Evaluate for signs of basal skull fracture:



    • Battle sign.


    • Raccoon eyes


    • Hemotympanum.


    • CSF leak (otorrhea, otorrhagia, rhinorrhea).


  • Monitor heart rate.



    • Bradycardia may precede decreased level of consciousness in the presence of an expanding mass lesion.


  • Evaluate for signs of herniation:



    • Progressive obtundation.


    • Mydriasis (unilateral, bilateral pupil dilatation). Pupil dilation is a critical lateralizing sign.




      • Medication (atropine) can be a confounding factor (pupils, HR).


      • Pupil dilatation can also be from direct trauma or contusions to the optic nerve.


      • In general, pupil dilatation is more lateralizing than limb weakness.


    • Contralateral hemiparesis (unilateral hemiparesis = Kernohan notch phenomenon).


    • Cushing’s triad (bradycardia, hypertension, irregular respirations): Most often late signs.


  • In infants: Check fontanel when assessing intracranial pressure (sunken, flat, full, bulging, tense).








TABLE 6-1 GCS Scores As Determined by Best Responses by Age




























Age


Best Motor


Best Verbal


Best Score


<6 mo


Flexion (4)


Smiles/cries (2)


10


6-12 mo


Localizes (5)


Smiles/cries (2)


11


1-2 yr


Localizes (5)


Sounds/words (4)


13


2-5 yr


Obeys (6)


Words/phrases (4-5)


15



Laboratory Investigations



  • Hemoglobin:



    • Initial hemoglobin level may not reflect intravascular volume status.


    • In older patients, hypovolemia must be excluded from other sources (abdominal, thoracic, and pelvic).


    • In older children and teenagers, intracranial bleeding will have mass effect before showing a decrease in hemoglobin.


    • Infants with intracranial bleeding (or scalp loss) might develop decreased hemoglobin or hypotension.


  • Electrolytes:



    • Sodium: Hyponatremia might cause neurologic findings in patients with decreased level of consciousness and unclear traumatic history.


  • Platelets and coagulation studies:



    • Brain injury and blood loss might lead to disseminated intravascular coagulation (DIC).


    • Patient may require surgery; therefore check coagulation status, and type and cross-match the blood.


Imaging


Role of Plain Radiographs



  • Except in a center where a CT-scan is unavailable, skull x-rays are not indicated.


  • When no CT is available:



    • Check for linear fractures going through the temporal region (middle meningeal artery: risk of epidural bleeding).


    • 29% of linear fractures are associated with intracranial lesions.4


    • Check for depressed fractures.


    • Check for pneumocephalus.


Role of Computed Tomography (CT)



  • Indications for CT-head3,6,7:



    • Any trauma with a persistent GCS below 15.


    • GCS = 15 but:



      • More than brief LOC or LOC of uncertain duration (persistent LOC is more important than a fracture for predicting intracranial hematoma).


      • Bradycardia.


      • Mechanism of injury especially concerning (fall from significant height, high-speed MVA).


      • 8.8% of patients will have positive findings on the CT scan when presenting with those criteria,3,4 but only 1% of patients with an initial GCS of 13 to 15 will need a neurosurgical intervention.3,8


    • Abnormal neurologic exam.


    • LOC with lucid interval but progressive worsening headaches.


    • Signs of important local trauma or skull base fracture.


    • All penetrating injuries.


    • Skull fracture (seen on x-ray, or for infants with falls, an obvious scalp abnormality may be a clue for a skull fracture).


  • What to look for on CT-head:



    • Contusions, subdural or epidural hematomas, subarachnoid blood.


    • Lesion leading to a mass effect, midline shift, herniation.



    • Disappearance of basal cisterns, shape of ventricles (indirect signs of edema), loss of sulci.


    • Gray/white matter differentiation.


    • Skull fractures (basal skull fracture: integrity of vessels).


    • Pneumocephalus.


    • Petechial hemorrhages indicating diffuse axonal injury.


    • Subdurals may be difficult to see; thin but diffuse subdurals can be massive.


  • Indications for CT-venogram:



    • Evidence of trauma near a venous sinus (occipital fracture), to ensure patency of the sinus and rule out a tear.


  • Indications for CT-arteriogram:



    • Basal skull fracture crossing the carotid canal, or evidence of blood in sphenoid sinus.


    • Any motor deficit unexplained by CT scan (suspect early infarction).



      • Beware of carotid dissection.


    • Unclear history of LOC before trauma and evidence of subarachnoid blood.


    • Crush injury to the head.


  • See Chapter 4 on Diagnostic Imaging for details.


Role of Magnetic Resonance Imaging (MRI)



  • MRI is not part of the primary survey.


  • MRI should be reserved for the trauma center.


  • Can be useful if CT does not explain a depressed consciousness level or to assess diffuse axonal injuries.


  • Unexplained neurologic deficit (check for parenchymal, brainstem or spinal cord lesions).


SPECIFIC INJURIES


Skull Fractures


Linear Skull Fracture



  • Definition: Linear fracture running through the entire thickness of bone without significant displacement.


  • Simple linear fracture: Most common type of fracture, especially in children <5 years old. Linear fractures increase risk of intracranial hematoma, but risk of hematoma is less in children compared to adults.


  • Basilar skull fractures represent 19% to 21% of all skull fractures.


  • Specific Types of Skull Fractures:



    • Longitudinal temporal bone fractures:



      • Conductive deafness (ossicular chain disruption); facial palsy, nystagmus, and facial numbness.


    • Transverse temporal bone fractures:



      • Nystagmus, ataxia (labyrinth), and permanent neural hearing loss (VIII).


    • Occipital condylar fracture:



      • Rare but serious injury.9


      • Associated with cervical spinal injuries, lower cranial nerve injuries, and hemiplegia or quadriplegia (needs CT/MRI evaluation).


  • Mechanism: Result from blunt trauma, usually low-energy over wide surface area.



    • Falls are more common cause than motor vehicle accidents.


  • Presentation: No clinical signs by itself, if not associated with other injuries—except in basal skull fracture (see below) and tempoparietal fracture that involve the cochlea and labyrinth.



    • A large, boggy, scalp contusion may predict a fracture.


  • CT findings: Linear fracture with no, or minimal, displacement (rule out epidural and subdural hematoma).


  • Management:



    • Admit infants with simple linear fractures for overnight observation regardless of neurologic status.


    • Treat neurologically intact patients with linear basilar fractures conservatively, without antibiotics.



    • Initially manage temporal bone skull base fractures conservatively. Tympanic membrane ruptures usually heal on their own.


    • Complex linear fractures may raise suspicion for nonaccidental injury.


Depressed Skull Fracture

Jun 22, 2016 | Posted by in EMERGENCY MEDICINE | Comments Off on Head Trauma: Surgical Management

Full access? Get Clinical Tree

Get Clinical Tree app for offline access