Level of Alertness
February 15th, 2021
Overview
The Glasgow Coma Scale (GCS) is a 15-point scale indicating level of consciousness.
How to Assess
- If the patient is not spontaneously opening their eyes, begin by attempting to elicit a response verbally. If this is unsuccessful then apply a painful stimulus such as a trapezius squeeze or a sternal rub.
If not done in this order, the examiner is unable to determine whether the patient responded to the painful stimulus or the voice.
Interpretation
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Causes of Reduced Glasgow Coma Scale
Intracranial
- Haemorrhage - intracerebral, subarachnoid, subdural, extradural
- Infarction
- Infection - meningitis, encephalitis, abscess
- Tumour - mass effect, cerebral oedema
- Post ictal state
- Head trauma - vascular, hypoxia, cerebral oedema, parenchymal injury
- Psychiatric - conversion disorder, depression, catatonia
Extracranial
- Cardiovascular - shock, hypertension
- Infection - septicaemia
- Metabolic - hypo/hyperosmolar states, hypo/hyperglycaemia, hypoadrenalism, hypothyroidism, hypopituitarism, electrolyte abnormality, hypercapnia
- Drugs / toxins - sedatives, analgesics, alcohol
- Physical injury - hyper / hypothermia, electrocution
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