MedSchool: Ace Your OSCEsThe Medical Company
GET - On the App Store
Cranial Nerves

Level of Consciousness

February 15th, 2021


The patient's level of consciousness is an assessment of their wakefulness and responsiveness to external stimuli.

The Glasgow Coma Scale (GCS)

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

  • The Glasgow Coma Scale (GCS)
  • Causes of Unconsciousness

  • 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, depression, catatonia
  • Extracranial

  • Cardiovascular - shock, hypertension
  • Infection - septicaemia
  • Metabolic - hypo/hyperosmolar states, hypo/hyperglycaemia, hypoadrenalism, hypothyroidism, hypopituitarism, electrolyte abnormality, hypoxia, hepatic failure, renal failure
  • Drugs / toxins - sedatives, analgesics, alcohol, encephalopathy
  • Physical injury - hyper / hypothermia, electrocution

Assessing Orientation

  • Ask About

  • Time - day, date, month, year, season
  • Place - floor, building, city, state, country
  • Person - full name, date of birth, address
  • Significance

  • Orientation is a quick way of assessing patients for confusion.
  • Causes of Confusion

  • Delirium - stroke, infection, intoxication / withdrawal, metabolic, neoplastic, seizure, sleep deprivation, severe pain, psychiatric
  • Dementia - Alzheimer's, vascular dementia, lewy body dementia
  • Poor compliance with examination
  • Intellectual disability
Next Page
Want more info like this?
  • Your electronic clinical medicine handbook
  • Guides to help pass your exams
  • Tools every medical student needs
  • Quick diagrams to have the answers, fast
  • Quizzes to test your knowledge
Sign Up Now

Snapshot: Initialising...