glascow coma scale

1. HEAD INJURY
Dr. Haydar Muneer Salih

2. Head Injury
Head injury is a frequent
cause of emergency
department attendance,
accounting for
approximately 3.4% of all
presentations.

3. Primary brian Injury
Primary brain injury occurs at
the time of impact and includes
injuries such as brainstem and
hemispheric contusions diffuse
axonal injury and cortical
lacerations.

5. Secondary Brian Injury
 Secondary brain injury occurs at some
time after the moment of impact and
is often preventable. The principle
causes of secondary brain injury are
hypoxia, hypotension, raised ICP,
reduced cerebral perfusion pressure
and pyrexia

6. Causes of secondary brain injury
■ Hypoxia: PO2 < 8 kPa
■ Hypotension: systolic blood pressure (SBP) <
90 mmHg
■ Raised intracranial pressure (ICP): ICP > 20
mmHg
■ Low cerebral perfusion pressure (CPP): CPP <
65 mmHg
■ Pyrexia
■ Seizures
■ Metabolic disturbance

7. Glasgow Coma scale

9. CLASSIFICATION OF HEAD INJURY
Glasgow Coma Score
Severity of head injury is classified according to the
Glasgow Coma Score (GCS)
• Minor head injury: GCS 15 with no loss of
consciousness (LOC);
• Mild head injury: GCS 14 or 15 with LOC;
• Moderate head injury: GCS 9–13;
• Severe head injury: GCS 3–8.

10. Taking a history in head injury
■ Mechanism of injury
■ Loss of consciousness or amnesia
■ Level of consciousness at scene and on transfer
■ Evidence of seizures
■ Probable hypoxia or hypotension
■ Pre-existing medical conditions
■ Medications (especially anticoagulants)
■ Illicit drugs and alcohol

11. MANAGEMENT OF MILD HEAD INJURY (GCS 14–15)
The following criteria must be met before discharge:
1. The patient must have accompanied by a responsible
adult
2. Should not be under the influence of alcohol or
other drugs;
3. verbal and written head injury advice must be given
to the patient and their accompanying adult

13. CT scan in a patient with mild head injury
■ Glasgow Coma Score (GCS) < 13 at any point
■ GCS 13 or 14 at 2 hours
■ Focal neurological deficit
■ Suspected open, depressed or basal skull fracture
■ Seizure
■ Vomiting > one episode
Urgent CT head scan if none of the above but:
■ Age > 65
■ Coagulopathy (e.g. on warfarin)
■ Dangerous mechanism of injury (CT within 8 hours)
■ Anterograde amnesia > 30 min (CT within 8 hours)

14. MANAGEMENT OF MODERATE TO SEVERE HEAD INJURY
 Begins with resuscitation and a primary survey
 The principle aim of treatment is the prevention of
secondary brain injury and this is best achieved by
the avoidance of hypoxia and hypotension.
 It follows that investigations such as a CT scan of
the head are of secondary importance to restoring
normal oxygenation and blood pressure

16.  The next appropriate step is a CT scan of the head
1. This investigation is aimed at identifying an
intracranial haematoma
2. The CT scan will also provide information about
scalp soft tissue injury
3. skull fracture, including base of skull fracture
4. lesions not requiring immediate surgery, such as
small intracerebral contusions

17. Extradural haematoma
 An extradural haematoma (EDH) is a
neurosurgical emergency. An EDH is nearly
always associated with a skull fracture and is
more common in young male patients. The
skull fracture is associated with tearing of a
meningeal artery and a haematoma
accumulates in the space between bone and
dura.

19.  The most common site is temporal, as the pterion
is not only the thinnest part of the skull but also
overlies the largest meningeal artery – the middle
meningeal
 when the patient complains of a headache but is
fully alert and orientated with no focal deficit.
After minutes or hours a rapid deterioration
occurs, with contralateral hemiparesis, reduced
conscious level and ipsilateral pupillary dilatation
as a result of brain compression and herniation

20. Extradural
Haematoma
The features of an
EDH on a CT scan
are a lentiform
(lensshaped or
biconvex)
hyperdense lesion
between the skull
and brain

21. Treatment
The treatment
of an EDH is
immediate
surgical
evacuation

22. Acute subdural haematoma
 Acute subdural haematoma (ASDH) differs
from EDH in terms of pathophysiology,
presentation and prognosis. An ASDH
accumulates in the space between the dura
and the arachnoid
 ASDH is nearly always associated with a
significant primary brain injury

24. Acute subdural haematoma
Patients with ASDH usually present
with an impaired conscious level from
the time of injury, but further
deterioration can occur as the
haematoma expands

25. The CT appearance
of an ASDH is also
hyperdense (acute
blood) but the
haematoma spreads
across the surface of
the brain giving it a
rather diffuse and
concave appearance.

26. Treatment
 The treatment of an ASDH is usually
evacuation via a craniotomy. Small
haematomas with little mass effect may be
managed conservatively in neurosurgical
centers.

27. Chronic subdural haematoma
 Chronic subdural haematomas (CSDH) usually occur
in the elderly and are more common in those on anti-
coagulant or antiplatelet agents. There is usually but
not always a history of minor head injury in the weeks
or months prior to presentation
 It is thought that small bridging veins tear and cause a
small ASDH which is clinically silent

28. Clinical features of CSDH include
headache, cognitive decline, focal
neurological deficits and seizures. It is
important to exclude hypoxic, metabolic and
endocrine disorders in this group of patients

29. chronic blood (> 2
weeks) is hypodense.
A CSDH will often
have areas of more
recent haemorrhage in
more dependent
(posterior) areas and is
then termed an acute-
on-chronic subdural
haematoma.

30.  Treatment of a CSDH and most acute-on-chronic
subdural haematomas is evacuation via burr hole(s)
rather than craniotomy.

31. Cerebral contusions
 Cerebral contusions are common in head
injury and result from the brain being
damaged by impacting against the skull
either at the point of impact (the ‘coup’) or
on the other side of the head (‘contre-coup’)
or as the brain slides forwards and
backwards over the ridged cranial fossa floor

32. CT appear
heterogeneous
with mixed
areas of high
and low density.

33.  Cerebral contusions rarely require immediate
surgical treatment. A head-injured patient
with cerebral contusions must be admitted
for observation as these lesions will tend to
mature and expand for 48–72 hours
following injury. A small proportion of
cerebral contusions will require delayed
surgical evacuation to reduce the mass effect

34. The Glasgow Outcome Score
(GOS)
Good recovery 5
Moderate disability 4
Severe disability 3
Persistent vegetative state 2
Dead 1