If you are presented with an unconscious patient, you should first examine the vital functions: pulse rate, breathing and blood pressure. The diagnostic work-up and treatment of disturbances in these functions fall outside the scope of this program.
Consciousness
Once you have checked the vital functions and, if necessary, restored them as far as possible, you should establish the degree of impaired consciousness. This should be done using the Glasgow Coma Scale EMV score (Eye, Motor, Verbal). There are standardised stimuli which have to be administered. Bear in mind that even with an optimal score
(15 points) there can still be impaired consciousness. The patient may be less alert or have a changing level of awareness.
The EMV score
E Opening the eyes
Investigate whether the patient:
- spontaneously opens their eyes when you enter the room
= 4 points - opens their eyes upon your request
= 3 points - opens their eyes in response to a pain stimulus, e.g. pressure on the supra-orbital nerve or fingernails [Figures 99, 100]
= 2 points - does not even open their eyes in response to pain
= 1 point
Figure 99
Figure 100
M The motor response
Investigate whether the patient:
- can carry out a task
= 6 points - can locate an administered (pain) stimulus (‘tell me where’ or ‘point to where you feel this’). For example, you could exert pressure on a fingernail or toenail
= 5 points - retracts the arm or leg to which you are administering the pain stimulus
= 4 points - abnormally flexes the arm or leg to which you are administering the pain stimulus
= 3 points - extends the arm or leg to which you are administering the pain stimulus
= 2 points - displays no motor response
= 1 point
If there is a difference between left and right, the best score should be used.
V Verbal reactions
Investigate whether the patient:
- is alert, i.e. knows what time it is, what day it is, where they are
= 5 points - is confused, i.e. disorientated to place and time
= 4 points - only uses isolated words out of context
= 3 points - only responds to questions and tasks with moans
= 2 points - does not respond to questions and tasks at all
= 1 point
Do not note only the total number of points, but the scores for the individual components as well (i.e., EMV: 8 (3,3,2)).
The patient’s reactions should also be carefully detailed, not because this will help you establish a diagnosis, but rather because the management plan and prognosis may be partly determined by the course and depth of the loss of consciousness.
Once you have carried out this examination, or even while you are still in the process of carrying it out, you should try to obtain the recent history from a third party. It is important to know the following:
- how the loss of consciousness developed: acute-onset, gradual, after a fall, etc.
- was the patient healthy prior to the loss of consciousness, in other words did they suffer from diabetes, heart problems, epilepsy, high fever?
- did the patient use medication and if so, which?
- did the patient use alcohol or other narcotics?
Sometimes a good third party history-taking can yield such a clear reason for impaired consciousness that you can start treatment immediately. While you are taking the patient’s history from the third party, you can make a start on the rest of the examination.
Remember that the patient’s condition can change. It is therefore important to regularly check the depth of the coma, as well as the breathing and circulation.
Respiration
Assess the patient’s respiration pattern. Kussmaul respiration generally indicates a diabetic coma. Cheyne-Stokes respiration indicates a cerebral lesion or congestive heart failure [Figure 101]. Hypoventilation can indicate barbiturate or opiate intoxication. If the hypoventilation is irregular, there may be a lesion in the medulla oblongata.
Figure 101
Breath odours
You should also smell the patient’s breath. A smell of acetone indicates a hyperglycaemic coma, and one of alcohol suggests intoxication.
Note: there can be another underlying cause of loss of consciousness other than alcohol consumption.
The tongue
Look in the patient’s mouth to determine whether they have bitten their tongue.
The head
Next, examine the patient’s head.
- Are there any wounds?
- Is there periorbital haematoma (‘panda or raccoon eyes’)?
- Is blood or fluid coming out of the ears or nose (consider a skull base fracture)?
- Is there a fixed head position?
Further examination
If the patient has been the victim of an accident or if other forms of trauma are expected, you should now examine the patient for fractures or internal bleeding in the rest of the body. Firmly palpate the arms, legs, chest, abdomen and back to investigate whether the patient feels pain anywhere. If the patient does not respond to pain stimuli, you will only be able to detect a fracture through an abnormal shape or position.
The eyes
If necessary open both the patient’s eyes and note the position of the eyes. If the head and eyes tend to one side (fixed gaze) with reduced muscle tone in the contralateral extremities, a lesion in the hemisphere on the side to which the gaze is directed is likely: ‘The patient’s gaze is towards the lesion’. If the head and eyes favour the side of clearly reduced muscle tone, a pontine lesion contralateral to the gaze direction is possible, but stimulation of the hemisphere contralateral to the gaze direction is also possible: ‘the patient’s gaze is directed away from the lesion’.
With a ‘skew deviation’ one eye is pointing inwards and down and the other is pointing upwards and out. This raises the suspicion of a pontine lesion.
The pupils
- Assess the shape and size of the pupils.
- Compare left and right.
- Assess the pupillary light reaction (refer to ‘The cranial nerves’).
In a patient who is unconscious due to a metabolic disorder, the pupils will usually be constricted, but will respond to a strong source of light.
A unilateral dilated pupil which is non-responsive to light is a symptom of a growth that is taking up space in one of the hemispheres, pushing the brainstem down and compressing it sideways against the cerebellar tentorium (compression of one oculomotor nerve). If both pupils are dilated and non-responsive, it indicates a diffuse cerebral swelling for example due to anoxia or a heavy overdose of sympathicomimetic drugs. If both pupils are very small, but slightly responsive to light, you should consider an opiate overdose.
The fundus
- Next examine the fundus of the eye, if possible, and look for signs of papillary oedema which indicates increased intracranial pressure. There may also be extensive preretinal bleeding, which may suggest arachnoidal haemorrhage (preretinal bleeding is not, however, a prerequisite for arachnoidal haemorrhage).
If you are convinced that there is no trauma to the neck, carry out the following:
- Determine whether there is any stiffness in the neck due to meningeal irritation (refer to ‘Signs of meningeal irritation’).
- Investigate compensatory eye movements: raise the head with both hands and, if necessary, open the patient’s eyes using your thumbs [Figure 102]; quickly turn the head horizontally and then vertically.
Figure 102
The eyes should stay in the midline position when the head is turned, or rapidly return to that position. If this is not the case, there is a loss of compensatory eye movements which indicates a functional brainstem disorder [Figure 103]. If there is diffuse bilateral hemisphere damage, you will often observe alternating drifting and divergent eye movements.
Figure 103
Final examination
Finally, you should round off the neurological examination by investigating whether hemiparesis can be demonstrated.
- Observe whether the facial muscles are symmetrical. Is there any sign of inflation of the cheek on the paralysed side upon expiration?
- Determine whether the corneal reflex can be elicited on both sides. If you observe a left/right difference, or if the reflex is absent even though the patient responds to pain stimuli, consider the possibility of a brainstem lesion.
- Look for signs of a corneomandibular reflex, which also indicates a brainstem lesion.
- Assess whether the left and right muscle tone in the limbs is the same. This can be done by lifting the patient’s arms or legs and then letting go again. Note whether one of the arms or legs imposes to be ‘heavier’ when dropping.
- If necessary, you can also examine the tendon reflexes to detect any left/right difference. Do not forget to investigate the plantar reflex as well. A positive Babinski’s sign indicates a pyramidal tract lesion. Bilateral Babinski’s sign indicates a pyramidal lesion in the brainstem, where the pyramidal tracts run close together.
Once you have carried out this examination, you will often be able to establish a probable diagnosis. If the patient is still unconscious and not yet in a hospital, hospitalisation for further diagnostic work-up and nursing care is indicated.