24B. Symptoms of raised intracranial pressure

From greek.doctor

Symptoms of increased ICP

  • Reduced level of consciousness
  • Headache and nausea, especially in the morning
  • Papilloedema -> blurred vision
  • Abducent palsy -> diplopia
  • Cushing triad/reflex
    • Hypertension
    • Bradycardia
    • Irregular respiration

Management of increased ICP

Besides treating the underlying cause, there are several ways to decrease ICP:

  • Head elevation to 30°
  • Mannitol i.v.
  • Hypertonic saline infusion
  • Controlled hyperventilation (to pCO2 26 – 30)
  • Glucocorticoids (only in case of CNS tumour)

Types of intracranial herniation

Generally, herniation can cause decrease level of consciousness, anisocoria, hemiparesis or tetraparesis.

Uncal transtentorial herniation occurs if the uncus herniates at tentorial incisure. This is often due to a unilateral mass effect. The clinical features are:

  • Impaired consciousness
  • Ipsilateral CN III palsy – Fixed, dilated pupil (Hutchinson’s pupil)
  • Contralateral motor deficit
  • Ipsilateral motor deficit (Kernohan’s sign)
    • Due to compression of the contralateral cerebral peduncle
    • (One of the rare cases where a cortical lesion causes ipsilateral motor signs)

Foramen magnum (tonsillar) herniation occurs if the cerebellar tonsils herniate through foramen magnum. This causes compression of brainstem, which impairs consciousness, circulation, and respiration, and can be deadly.