head trauma

Last edited 05/2023 and last reviewed 06/2023

Head injury remains a major cause of death, especially in the young. Many die in the initial impact. Of those who survive and remain in coma for 6 hours, 40% die within 6 months.

• head injury is defined as any trauma to the head other than superficial injuries to the face (1,2)
  • head injury is the commonest cause of death and disability in people aged 1-40 years in the UK
    • each year, 1.4 million people attend emergency departments in England and Wales with a recent head injury
    • between 33% and 50% of these are children aged under 15 years
    • annually, about 200,000 people are admitted to hospital with head injury
    • of these, one-fifth have features suggesting skull fracture or have evidence of brain damage
    • most patients recover without specific or specialist intervention, but others experience long-term disability or even die from the effects of complications that could potentially be minimised or avoided with early detection and appropriate treatment
      
      
• incidence of death from head injury is low, with as few as 0.2% of all patients attending emergency departments with a head injury dying as a result of this injury
  • ninety five per cent of people who have sustained a head injury present with a normal or minimally impaired conscious level (Glasgow Coma Scale [GCS] greater than 12) but the majority of fatal outcomes are in the moderate (GCS 9-12) or severe (GCS 8 or less) head injury groups, which account for only 5% of attenders
    • therefore, emergency departments see a large number of patients with minor or mild head injuries and need to identify the very small number who will go on to have serious acute intracranial complications
    • estimated that 25-30% of children aged under 2 years who are hospitalised with head injury have an abusive head injury

In some patients (for example, patients with dementia, underlying chronic neurological disorders or learning disabilities) the pre-injury baseline GCS may be less than 15

Be aware that any severity of head injury can cause pituitary dysfunction. This may present immediately, hours, weeks or months after the injury. A variety of symptoms could indicate hypopituitarism (2):

• in people admitted to hospital with a head injury who have persistently abnormal low sodium levels or low blood pressure, consider investigations for hypopituitarism
• in people presenting to primary or community care with persistent symptoms consistent with hypopituitarism in the weeks or months after a head injury, consider investigations or referral for hypopituitarism
• can occur immediately after a head injury or in the weeks to months afterwards
• consider further endocrinology investigations for people who have been discharged after a head injury if they have persistent symptoms consistent with hypopituitarism or are not recovering as expected

Recovery depends upon the nature of the injury

• residual effects are both physical, e.g. hemiparesis, dysphasia; and mental, e.g. impaired intellect, memory, and behavioural problems.

The extent of recovery is often correlated with the duration of post-traumatic amnesia. As a guide, post- traumatic amnesia of more than 28 days is rarely associated with a return to work. Post-traumatic amnesia of more than one week is likely to impair higher intellectual activity. That of less than one day should allow a return to previous activity after several months. The prognosis is better for younger patients, worse for older ones.

Most of the improvement is within the first 6 months. Physiotherapy and occupational therapy have important roles, both in overcoming physical disability and in stimulating motivation.

Notes:

• underactivity of the pituitary gland that can result in:
  • adrenocorticotropic hormone deficiency
    • leading to weakness, fatigue, weight loss, hypotension, hyponatraemia, hypoglycaemia, hypercalcaemia, anaemia and fatigue
  • growth hormone deficiency
    • resulting in decreased energy, low mood, neuropsychiatric and cognitive symptoms, decreased lean body mass, increased fat mass, altered metabolic profile and decreased exercise capacity
  • lack of sex hormones
    • delayed puberty, hot flushes, fatigue, tiredness, loss of body hair, reduced sex drive, irregular periods, erectile dysfunction and reduced fertility
  • thyroid-stimulating hormone deficiency
    • presenting with slow growth, fatigue, lethargy, cold intolerance and weight gain
• vasopressin deficiency
  • causing polyuria, polydipsia, nocturia and incontinence

Reference:

• NICE (June 2017). Head injury: assessment and early management
• NICE (May 2023). Head injury: assessment and early management