• immediate management;
• delayed management.
In practice, the initial assessment and immediate management frequently overlap according to clinical priorities.
Initial assessment
The initial assessment is an active process and not just a period of history taking. However, the history Blow
Direct 'coup' injury
'Contre-coup' injury from brain hitting opposite part of skull
Figure 15.1 Coup and contre-coup injuries – mechanism.
2Harvey Cushing (1869–1939), Professor of Surgery, Harvard Medical School, Boston, MA, USA. He was one of the founders of neurosurgery.
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is most important, in particular the account of a wit- ness, as most victims of major head injuries are un- able to give an accurate history.
History
Important points to note in the history are as follows.
• The mechanism of the injury. This may enable some prediction as to the likely injuries, both vis- ible and within the cranium. The nature of the injurious force and its direction relative to the re- cipient are important.
• The immediate condition of the injured person.
What was the patient like immediately after the in- jury? In particular, note the level of consciousness in terms of an accepted scale such as the Glasgow Coma Scale (see Box 15.3), as well as other vital signs (pulse, respiration, blood pressure), the size and reaction of the pupils and recorded limb movements (was the patient moving his or her arms and legs after the accident?).
• Any change in the condition of the injured person.
As well as establishing the patient’s condition when first seen after the injury, it is also important to establish whether the condition has changed at all. For example, if the patient was talking and moving all limbs and is now comatose, it suggests that an intracranial mass lesion such as an intrac- ranial haemorrhage is developing.
• The prior condition of the injured person. As much history about the injured as possible should be obtained from relatives and friends. Was the pa- tient drunk at the time? Is the patient diabetic and so could the coma be hypoglycaemic? Does the patient have a glass eye or is he or she on treat- ment for chronic glaucoma to account for the ab- sence of pupillary responses?
• What other injuries has the person sustained? Pa- tients who are unstable due to severe chest or abdominal trauma need these managing first to prevent secondary brain injury.
Examination
Your examination should reassess the patient’s con- scious level to decide whether the condition has worsened or improved, and look for associated in- juries, in particular major occult injuries such as a tension pneumothorax or fractured spine. In patients with major injuries, the priorities for examination are usually quoted in terms of the ABC of resuscitation, to which may be added an additional C.
• Airway. Is the airway clear without obstruction such as vomitus or blood? If the patient is not maintaining the airway, intubation with an en- dotracheal tube should be performed. Occasion- ally, this may not be possible and a tracheostomy may be required.
• Breathing. Is the patient breathing spontaneously or should ventilation be instituted? Controlled hy- perventilation may be desirable to reduce intrac- ranial pressure (see Chapter 14). An arterial blood sample for estimation of oxygen carriage should be taken as soon as convenient, and the patient should be monitored by pulse oximeter to ensure adequate haemoglobin saturation.
• Circulation. The patient’s pulse and blood pres- sure should be taken and monitored. Raised in- tracranial pressure results in bradycardia and hypertension (Cushing reflex; see earlier in this chapter). Hypotension is rarely due to head injury and an alternative cause should be sought (a rup- tured spleen, a haemothorax or a fractured pelvis, for example). Occasionally, extensive scalp bleed- ing may result in hypotension, as may a head in- jury in a child.
• Cervical spine. Every patient who sustains a head injury should be considered to have a cer- vical spine injury as well until proved otherwise by good-quality radiography or CT scan. The neck should therefore be immobilized in a hard collar.
Following the initial ABC, a full central nervous system (CNS) examination should be performed as well as complete examination of the chest, abdo- men and limbs. Particular attention should be paid to the parts that are usually forgotten, including examining the back for evidence of trauma and in- tegrity of the spine, and a rectal examination with particular attention to anal tone (or its absence in spinal injury) and the position of the prostate in the male (a ruptured urethra results in a displaced prostate).
The conscious level: the Glasgow Coma Scale
Vague terms such as comatose, semi-comatose, un- conscious, stuporose and so on should be avoided;
they may be of value to a psychiatrist but not to a sur- geon. Instead, the conscious level is charted accord- ing to the patient’s motor, verbal and eye-opening responses to stimuli; these are very much the reac- tions of a patient recovering from deep anaesthesia.
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Head injuryBox 15.3 The Glasgow Coma Scale (GCS) Eye opening
4 Spontaneously 3 To speech/command 2 To pain
1 None
Best verbal response
5 Orientated – knows who he or she is and where he or she is
4 Confused conversation – disorientated; gives confused answers to questions
3 Inappropriate words – random words; no conversation
2 Incomprehensible sounds 1 None
Best motor response 6 Obeys commands 5 Localizes pain
4 Flexes to pain – flexion withdrawal of limb to painful stimulus
3 Abnormal (decorticate) flexion – upper limb adducts, flexes and internally rotates so that it lies across chest; lower limbs extend (Figure 15.2) 2 Extends to pain (decerebrate) – painful stimulus
causes extension of all limbs 1 None
When assessing the GCS, it is very important that an adequate stimulus is applied.
Arms adducted, flexed and internally rotated to lie across chest
Legs extended Ankles plantar flexed
Arms extended and internally rotated
Legs extended Ankles plantar flexed as in decorticate
Decorticate Decerebrate
Figure 15.2 Decerebrate and decorticate postures.
The most commonly used scale is the Glasgow Coma Scale (GCS) (Box 15.3), in which the responses within each group are allotted a score, the normal being 15.
A mild head injury may score 13–15, a severe injury 8 or less.
Pupil size and responses
If a cerebral hemisphere is pressed upon by an en- larging blood clot, the third cranial nerve on that side becomes compressed by descent of the uncus over
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the edge of the tentorium cerebelli. Paralysis of the third nerve (which transmits parasympathetic pupil- loconstrictor fibres) results in dilation of the corre- sponding pupil (owing to the intact unopposed sym- pathetic supply) and failure of the pupil to respond to light. An important sign of cerebral compression is, therefore, dilation and loss of light reaction of the pupil on the affected side although, occasionally, pu- pillary dilation will be a false localizing sign and will be on the side opposite the mass lesion. Because the optic nerve pathway is intact, a light shone into this unreacting pupil produces constriction in the oppo- site pupil (consensual reaction to light). As compres- sion continues, the contralateral third nerve becomes compressed, and the opposite pupil in turn dilates and becomes fixed to light.
Bilateral fixed dilated pupils in a patient with head injury indicate very great cerebral compression from which the patient rarely recovers. Occasionally, local trauma to the nerves from extensive skull-base frac- tures may produce the same findings.
Pulse, respiration and blood pressure
With increasing intracranial pressure, the pulse slows and the blood pressure rises (Cushing reflex; see ear- lier in this chapter), the respirations become stertori- ous and eventually Cheyne–Stokes3 in nature.
Special investigations
With respect to head injury, there are three immedi- ate investigations that may be indicated.
1 Skull Xray used to be the initial investigation but has been replaced owing to the ready availability of CT. It may have a role in children as part of a skeletal survey in suspected non-accidental in- jury.
2 CT scan should be performed on all patients with significant head injuries (Box 15.4) as indicated by impaired conscious level (GCS <15), history of penetrating injury or suspected fracture, signs of a basal skull fracture (e.g. CSF rhinorrhoea or otorrhoea, bilateral orbital haematoma [Battle’s sign]), post-traumatic seizure, focal neurological deficit or recurrent (>1) vomiting or amnesia for more than 30 min prior to impact. Other indica- tions include a history of loss of consciousness or
amnesia and a history of significant trauma, coag- ulopathy (e.g. patient on anticoagulation), or age over 65 years. The resulting images may then be viewed locally or transmitted to a regional neuro- surgical centre for specialist opinion.
3 Cervical spine Xray is necessary in all uncon- scious patients following head injury, unless in- cluded in the CT scan. Other indications include neck pain and/or tenderness with a history of possible neck trauma, or where exclusion of neck trauma is necessary prior to intubation for other surgery.