Graham Teasdale and Bryan J. Jennett developed the Glasgow coma scale/score in 1974. They were professors of neurosurgery in the University of Glasgow, Scotland, UK.
Glasgow coma scale (GCS) is a tool commonly used by healthcare providers, especially nurses and doctors. It is a neurological scale or scoring system that helps to assess the level of consciousness of patients and the overall status of the central nervous system.
There are three areas of examination in GCS.
1. Eye opening – E
2. Verbal response -V
3. Motor response – M
The GCS is the cumulative score of three areas of examination. Eye opening is graded from 1 to 4; verbal response from 1 to 5; motor response from 1 to 6.
E-V-M = 4-5-6
EYE OPENING (E)
Spontaneous – 4
Command – 3
Pain – 2
No response – 1
Spontaneous: If patient opens eyes during assessment or by verbal arousal (for instance when his/her name is called), score 4.
Command: If patient opens eyes only when commanded to do so, score 3. For example, if the nurse says, “Mr K.B, please open your eyes” and the patient obeys the command by opening his eyes, score 3.
Pain: If patient opens eyes only to painful stimulation, score 2. This can be done through applying pressure to the nail bed or the supra-orbital notch, rubbing patient’s sternum firmly with the knuckles of closed fist, and pinching the trapezius muscles.
No response: If patient does not open eyes despite painful stimulation, score 1.
SPECIAL CONSIDERATION: Patients with peri-orbital oedema may not be able to open their eyes. In this case, the nurse scores 1 under eye opening, indicating the reason. For example:
E1 (oedema); V3; M4
GCS = 8.
VERBAL RESPONSE (V)
Converses and oriented – 5
Converses but disoriented or confused – 4
Inappropriate words – 3
Incomprehensible sound – 2
No response – 1
Questions that pertain to ascertaining patient’s orientation to time, place and person, should be asked. The nurse asks questions such as “Mrs R.M, where are you now?”. If patient says, “I am in the hospital”, it shows that patient converses and is oriented. So the patient scores 5.
If the same question is asked and the patient answers, “I am inside a bus”, it shows patient is disoriented or confused, though in a conversational manner. The patient scores 4.
If patient is asked, “Prof T.Y, what time of the day are we?”, and the patient gives a response that is completely out of tune, such as, “I won a visa lottery yesterday”, the patient scores 3 because the answer is inappropriate and out of context, that is, the response is not conversational.
If patient makes incomprehensible sounds such as groaning or moaning (with or without painful stimulation), score 2.
If there’s no verbal response at all despite painful stimulation, score 1.
Patients that are intubated (with endotracheal tube or tracheotomy tube) will be scored 1 under verbal response due to their inability to speak. The nurse must indicate this in her assessment. For example,
E4; V1 (intubated); M6
GCS = 11T
Obeys command – 6
Localizes pain – 5
Flexion withdrawal – 4
Abnormal flexion (decorticate) – 3
Abnormal extension (decerebrate) – 2
No response – 1
If patient moves hands and legs in response to command, score 6. The nurse may put her hands in patient palm and ask patient to hold her tight.
If patient cannot obey command, the nurse inflicts pain on the patient by sternal rub or applying pressure on the nail bed or supra-orbital notch or pinching the trapezius muscles. If patient takes his hands directly to the source of pain and removes the nurses hand at the site of painful stimulation, score 5. It simply means patient is localizing pain.
In flexion withdrawal (score 4), the patient pulls the limb away (withdraws) from the painful stimulus.
Abnormal flexion is also called decortication or decorticate posturing (also called “mummy pose”). Here, the arms are adducted (drawn towards the body) and flexed. The fist is clenched and the wrist flexed and placed on the chest. This describes “mummy pose”. Also the legs are extended and internally rotated and planter-flexed. If a patient demonstrate these features, score 3. It’s a sign of damage to the cerebral cortex.
Abnormal extension is also called decerebration or decerebrate posturing. Here, the arms are extended, adducted and pronated. The wrists are flexed and the the fixed clenched and rotated outward. The legs are extended and plantar flexed. The teeth are also clenched. These features are signs of severe damage to the brain – irritation or excitation of the brainstem or lesion in the brainstem.
The motor response of patients with spinal cord injury, especially those who are paraplegic , cannot be assessed due to their motor response deficit. Therefore, it must be noted during assessment.
CLASSIFICATIONS OF HEAD INJURY.
Head injury can be classified into three groups using the Glasgow coma scale:
GCS 13-15 (Mild head injury)
GCS 9-12 (Moderate head injury)
GCS 3-8 (Severe head injury)