Head Injury Flashcards
Head Injury
Head injury: types of traumatic brain injury
Basics
- primary brain injury may be focal (contusion/haematoma) or diffuse (diffuse axonal injury)
- diffuse axonal injury occurs as a result of mechanical shearing following deceleration, causing disruption and tearing of axons
- intra-cranial haematomas can be extradural, subdural or intracerebral, while contusions may occur adjacent to (coup) or contralateral (contre-coup) to the side of impact
- secondary brain injury occurs when cerebral oedema, ischaemia, infection, tonsillar or tentorial herniation exacerbates the original injury. The normal cerebral auto regulatory processes are disrupted following trauma rendering the brain more susceptible to blood flow changes and hypoxia
- the Cushings reflex (hypertension and bradycardia) often occurs late and is usually a pre terminal event
Extradural (Epidural) Haematoma
Bleeding into the space between the dura mater and the skull. Often results from acceleration-deceleration trauma or a blow to the side of the head. The majority of epidural haematomas occur in the temporal region where skull fractures cause a rupture of the middle meningeal artery.
Features
features of raised intracranial pressure
some patients may exhibit a lucid interval
Subdural Haematoma
Bleeding into the outermost meningeal layer. Most commonly occur around the frontal and parietal lobes.
Risk factors include old age, alcoholism and anticoagulation.
Slower onset of symptoms than a epidural haematoma.
Subarachnoid Haemorrhage
Usually occurs spontaneously in the context of a ruptured cerebral aneurysm but may be seen in association with other injuries when a patient has sustained a traumatic brain injury
Head Injury NICE Guidelines
NICE has strict and clear guidance regarding which adult patients are safe to discharge and which need further CT head imaging. The latter group are also divided into two further cohorts, those who require an immediate CT head and those requiring CT head within 8 hours of injury
Head Injury - CT Head Immediately
CT head immediately GCS < 13 on initial assessment GCS < 15 at 2 hours post-injury suspected open or depressed skull fracture. any sign of basal skull fracture (haemotympanum, 'panda' eyes, cerebrospinal fluid leakage from the ear or nose, Battle's sign). post-traumatic seizure. focal neurological deficit. more than 1 episode of vomiting
Head Injury - CT Head within 8 hours
CT head scan within 8 hours of the head injury - for adults with any of the following risk factors who have experienced some loss of consciousness or amnesia since the injury:
age 65 years or older
any history of bleeding or clotting disorders
dangerous mechanism of injury (a pedestrian or cyclist struck by a motor vehicle, an occupant ejected from a motor vehicle or a fall from a height of greater than 1 metre or 5 stairs)
more than 30 minutes’ retrograde amnesia of events immediately before the head injury
Head Injury and Warfarin
If a patient is on warfarin who have sustained a head injury with no other indications for a CT head scan, perform a CT head scan within 8 hours of the injury.
Concussion - Mx
Typically, the effects of concussion resolve spontaneously within 7-10 days. To minimise the risk of persistent symptoms, A 2-3 day period of complete mental and physical rest is recommended. Should symptoms settle following this period, then an individual should gradually return to normal activities over a 2 week period. Following successful completion of a return to normal activities, a graduated return to sporting activity is appropriate, slowly building up to full contact sports. At each point in the process of recovery, a relapse of symptoms suggests the need to return to the previous stage. This cautious approach to recovery is intended to minimise the risk of future complications; for example, chronic traumatic encephalopathy.
Concussion - Example Question
A 20-year-old man is referred to neurology after presenting at the emergency department. The patient reported suffering a head injury during a rugby match approximately 24 hours ago. He had presented to the hospital due to symptoms of an ongoing headache and an inability to concentrate when he had returned to work that morning.
The patient had hit his head on the knee of another player while attempting to make a tackle. The patient did not lose consciousness after his injury but had been mildly disorientated and so took no further part in the match. The patient had gone home to rest and had experienced a moderate generalised headache that had not responded to paracetamol. Ever since the injury he described feeling ‘in a fog’ and had had a disrupted night’s sleep. At no point after the injury had the patient lost consciousness, suffered a seizure or vomited. The patient also denied any pain or discomfort associated with his neck.
The patient was normally in excellent physical health with no significant previous medical problems. In particular, the patient had no personal or family history of bleeding or clotting disorders. The patient took no regular medications and had no known drug allergies. The patient was a semi-professional rugby player who worked part-time in a coffee shop.
The patient was alert and fully orientated to time, place and person. External examination of the patient’s head and neck was unremarkable; in particular, there was no significant bruising to the patient’s orbits or behind his ears and there was no evidence of haemotympanum. No evidence of focal neurology was found on detailed examination of the patient’s cranial nerves and peripheral nervous system.
What is the appropriate initial management of the patient’s head injury?
Resume normal activities but avoid contact sports for 7 days CT brain scan within 8 hours of presentation MRI brain scan within 24 hours of presentation > Complete physical and mental rest for 2-3 days Admit to hospital for observation for 48 hours
The patient has suffered a concussion following his head injury. Concussion is a clinical diagnosis describing the signs and symptoms of neurological and cognitive impairment resulting from a head injury. The patient’s symptoms of a headache and poor concentration are typical for an individual suffering the effects of a concussion. Other common symptoms include amnesia, lability of mood, irritability, slow reaction times and insomnia.
Typically, the effects of concussion resolve spontaneously within 7-10 days. To minimise the risk of persistent symptoms, A 2-3 day period of complete mental and physical rest is recommended. Should symptoms settle following this period, then an individual should gradually return to normal activities over a 2 week period. Following successful completion of a return to normal activities, a graduated return to sporting activity is appropriate, slowly building up to full contact sports. At each point in the process of recovery, a relapse of symptoms suggests the need to return to the previous stage. This cautious approach to recovery is intended to minimise the risk of future complications; for example, chronic traumatic encephalopathy.
The patient in the question does not meet criteria for brain imaging as recommended by NICE guidance of head injuries. Admission to hospital for observation is unnecessary in this case.
Head Injury - Indication for CT: Example Question
A 52 year old male is brought to A&E by his concerned wife after tripping and falling down a flight of 12 stairs at home, hitting his head on the way down. The patient himself is not concerned and believes he could have stayed at home.
He denies headache, reports no nausea or vomiting, no seizures and did not lose consciousness between the fall and when you examine him. He is not taking any regular medications including anticoagulants and remembers the whole episode except for about 20 seconds after landing at the bottom of the floor. On examination, he has no limb weakness or loss of sensation. His pupils are equal and reactive bilaterally. What is the most appropriate management?
Discharge, no further investigations required Discharge, outpatient CT head within 72 hours Observe for 24 hours and discharge if no deterioration CT head immediately > CT head within 8 hours of injury
The patient has presented with a mechanical fall with a dangerous mechanism of injury.
Head injury - Mx: Example Question
A 70-year-old man with a history of hypertension and benign prostatic hypertrophy is brought in by ambulance after a fall. He reports he felt dizzy after standing up from his arm chair, stumbled and tripped over his cat. His wife, who witnessed the fall, reports that he then hit his head on the coffee table a lost consciousness for around 1 minute.
She describes no abnormal movements or incontinence. On regaining consciousness he was oriented immediately. He remembers regaining consciousness. He has no headache, dizziness, nausea or vomiting.
On examination, he has a small laceration on his forehead. His pupils were equal and reactive to light. He had no focal neurological deficits. He was a 15 on the Glasgow Coma Scale. His abbreviated mental test score was 10/10.
ECG: Sinus rhythm. 70 beats per minute. No T wave or ST segment changes.
Blood pressure (lying): 135/75 mmHg Blood pressure (standing): 110/60 mmHg
Haemoglobin 135 g/dl
Troponin T 1 ng/L
Urine dip: trace of protein
What is the most appropriate course of action?
Admit for CT head within 1 hour > Admit for CT head within 8 hours Admit for CT head within 24 hours Discharge to return for CT head next day Discharge with outpatient follow-up, no imaging required
Nice Guidelines on head injury state that:
‘For adults who have sustained a head injury and have any of the following risk factors, perform a CT head scan within 1 hour of the risk factor being identified:
GCS less than 13 on initial assessment in the emergency department.
GCS less than 15 at 2 hours after the injury on assessment in the Emergency Department.
Suspected open or depressed skull fracture.
Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign).
Post-traumatic seizure.
Focal neurological deficit.
More than 1 episode of vomiting.’
The patient does not meet any of these criteria, so CT head within 1 hour is not mandatory.
The guideline then also states:
‘For adults with any of the following risk factors who have experienced some loss of consciousness or amnesia since the injury, perform a CT head scan within 8 hours of the head injury:
Age 65 years or older.
Any history of bleeding or clotting disorders.
Dangerous mechanism of injury (a pedestrian or cyclist struck by a motor vehicle, an occupant ejected from a motor vehicle or a fall from a height of greater than 1 metre or 5 stairs).
More than 30 minutes’ retrograde amnesia of events immediately before the head injury.’
As this gentleman had a period of unconsciousness and is over 65, he should have a CT head within 8 hours.
Post Concussion Syndrome
Seen even after minor head trauma
Eg 2 weeks post RTA - anxiety, headache, lethargy. CT Normal
- Headache
- Fatigue
- Anxiety/depression
- Dizziness
Complete resolution of Sx within 6m
(NB in contrast to PTSD where onset of Sx is usually delayed and tends to run a prolonged course)
