Extradural Haemorrhage

Synonyms: extradural haematoma, EDH; and epidural haemorrhage and epidural haematoma if the lesion is of the spinal cord.

Extradural haemorrhage is a collection of blood in the potential space between the dura and the bone. Usually that bone is the skull but extradural haemorrhage can occur in the spinal column. This may follow the trauma of epidural anaesthesia or lumbar puncture. When it is spontaneous there is usually a coagulation or platelet defect.

Extradural haemorrhage is most often due to a fractured temporal or parietal bone damaging the middle meningeal artery or vein with blood collecting between the dura and the skull. It is typically caused by trauma to the temple just beside the eye, although it may also follow a tear in dural venous sinuses. Children are less likely to have an associated skull fracture than adults. Posterior fossa extradural haemorrhage is rare.¹

It occurs in about 2% of all cases of head injury but 5 to 15% of cases of fatal head injury. Around 30% of cases are acute, 30% subacute and 10% chronic. Males outnumber females by 4:1. It is rare in small children because of the plasticity of the skull and is less common over the age of 60 because the dura is tightly adherent.

There are 2 peaks in incidence. One is in childhood and the other in the 40s and 50s. The prognosis is poorer in the older group.

• There is usually a history of trauma and head injury that causes loss of consciousness.
• Classically this is followed by a lucid interval after which the patient deteriorates. However, this "classical" presentation occurs in less than a third of cases. Extradural haemorrhage in the posterior fossa can produce a very rapid deterioration to death, measured in minutes.

A haematoma in the skull may produce a number of changes that should be sought in a patient who has suffered a serious head injury, especially if there was loss of consciousness:

• Headache
• Nausea or vomiting
• Seizures
• Bradycardia with or without hypertension, indicates raised intracranial pressure
• Evidence of skull fractures, haematomas, or lacerations
• Cerebrospinal fluid (CSF) otorrhoea or rhinorrhoea resulting from skull fracture with a tear of the dura
• Alteration in level of consciousness with deterioration of the Glasgow Coma Scale score
• Unequal pupils
• Facial nerve injury
• Weakness of limbs
• Other focal neurological deficits include aphasia, visual field defects, numbness and ataxia
• Always remember patients seen in casualty with EDH may also have a traumatic cervical spine injury.

A haematoma in the spinal column will produce compression of the cord. There may be radicular symptoms or a complete cord compression. Presentation may include:

• Weakness
• Numbness
• Alteration in reflexes
• Urinary incontinence
• Possibly both urinary and faecal incontinence

People with a head injury are often intoxicated and it may de difficult to know if any deterioration in level of consciousness is due to a haemorrhage or the effects of alcohol or drugs.

Baseline FBC and U&E are in order. If there is any suspicion of abnormality of coagulation, as with a spontaneous haemorrhage, then platelets and coagulation studies are required.

• Plain x-ray of the skull may show a fracture
• X-ray cervical spine with views of the odontoid peg. Spinal injury must be excluded
• CT gives much more information. It may show a haematoma or air pockets.
• If there is deterioration, CT must be repeated.
• MRI gives very good images but may not be suitable for a patient in an unstable condition
• Lumbar puncture should be avoided, especially if raised intracranial pressure has not been excluded

• If the patient is unconscious, the basic ABC of resuscitation must be employed.
• Maintain an airway and treat the neck with great care until injury has been excluded. Oxygen may be given.
• A full trauma assessment must be made. There may be fractured bones or a ruptured liver or spleen.
• IV fluids may be required to maintain the circulation and preserve cerebral perfusion.

Further management depends upon the condition of the patient.

• An alert patient with a small haematoma may be treated conservatively but must be observed in case of sudden deterioration.
• If intracranial pressure is raised, it may be treated with osmotic diuretics such as IV mannitol. If ventilation is required, hyperventilation, with elevation of the head of the bed to 30° will help further but excessive hypocapnia should be avoided as it causes cerebral vasoconstriction.
• Burr holes may be required to evacuate a haematoma.
• Intervention is required for a large haematoma and conservative management is in order for a small one but between those extremes, clinical judgement must be exercised.²
• There may well be other injuries that also need attention and priorities must be set.

There are a number of other issues with the seriously ill patient such as low dose heparin to prevent deep vein thrombosis and acid suppression to prevent gastric erosions. Anticoagulation in the presence of EDH has potential danger and TED stockings alone may be safer. It is a difficult balance.

• Neurological deficits can be temporary or permanent. Death may occur.
• Post traumatic seizures due to cortical damage may develop 1 to 3 months after the injury. The risk diminishes with time. Alcoholism increases the risk of posttraumatic seizures. Prophylactic phenytoin may reduce seizures in the first week but it has no long term benefit.³
• Delayed effects include the postconcussion syndrome, which is characterised by headaches, dizziness, vertigo, restlessness, emotional lability, inability to concentrate and fatigue.
• Spinal EDH may cause spasticity, neuropathic pain, and urinary complications.

• Prognosis declines with advancing age and is poor over 65. Despite this, there is often a bias against transferring older people to a neurosurgical centre.⁴
• Those who are alert on admission rarely die but the mortality in the comatose is 40%. The overall mortality rate is between 10 and 30%.
• The outcome is improved by expeditious treatment, but less than a third of patients with best initial Glasgow Coma Score below 8 will do well.
• In patients who underwent surgery there are 4 features that predict outcome:⁵
  • Associated brain injury
  • Best motor response
  • Volume of the haematoma
  • Length of stay in hospital

• Crash helmets for motor cyclists have been compulsory for some years but they are not obligatory off the public highway. Helmets for cyclists should be used more often and also for skateboarding, snowboarding, etc.
• Alcohol is often a contributing factor, whether this is drinking and driving or binge drinking followed by falls or fighting.
• Head guards do not protect the brain in boxing⁶ and the BMA has advised for many years that the sport should be banned.⁷ Boxing is by far the commonest cause of head injures but the second commonest cause in sport is equestrian events. Appropriate immediate management of injured sportsmen at the place of injury is essential to prevent further injury.⁸