14. Nervous System II - Pathologies Flashcards
(103 cards)
Raised Intracranial Pressure: definition
Increase in pressure within the cranial cavity
Raised Intracranial Pressure: pathophysiology
Compression of blood vessels leads to reduced oxygen perfusion to the brain
Raised Intracranial Pressure: aetiology
- Tumours - gliomas (primary), metastases
- Haemorrhage - subdural (venous, slow), subarachnoid (arterial, rapid)
- Hydrocephalus - excess CSF
- Meningitis - inflammation of meninges
- Encephalitis - inflammation of brain tissue
- Intracranial abscess
Raised Intracranial Pressure: signs and symptoms
Headache - worse on awakening*, when coughing or moving head
Vomiting - often without nausea
Visual disturbance - if damage to optic nerve
Pupil fixed/dilated in one eye
Impaired mental state
Altered speech
Seizures
Papilloedema - bulging of the optic disc
Elevated blood pressure, slow irregular pulse, slow breathing
*CSF at daily peak
Hydrocephalus: definition
Abnormal accumulation of CSF in the cerebral ventricles and subarachnoid space
Hydrocephalus: pathophysiology
Impaired absorption or excessive secretion
Results in ventricular dilation
CSF permeates through the ependymal lining into the surrounding white matter
Hydrocephalus: aetiology - young children
Infection or congenital malformation
Hydrocephalus: aetiology - older children/adults
Tumour
Trauma
Meningitis
Hydrocephalus: signs and symptoms
Headache - worse on awakening - CSF doesn’t drain well whilst lying down
Infants - increase in head circumference and dliated scalp veins
Vomiting, nausea
Blurred or double vision
Neck pain
Hydrocephalus: allopathic treatment
Diuretics - inhibit CSF secretion
Shunt, ventricular drain, lumbar puncture
Emergency - to prevent white matter scarring/brain damage/death
Meningitis: definition
Infection or inflammation of the meninges
Can be life-threatening if leads to intracranial pressure
Meningitis: aetiology
Viral meningitis (herpes simplex) - most common cause (90%). Less severe
Bacterial infection - more serious
Fungal/parasitic micro-organisms
Non-infective - brain tumour
Meningitis: signs and symptoms
Can initially resemble flu:
Fever Sudden onset of severe headache Neck stiffness Photophobia Vomiting
Petechiae - small purple/red spots on skin as result of tiny haemorrhages that don’t disappear under pressure (non-blanching)
Kernigs sign - pain resistance to knee extension when lying with the hips fully flexed
Brudzinski sign - neck flexion causes flexion of hip and knee
Meningitis: diagnostics
Lumbar puncture: withdraw CSF between L4-L5
Meningitis: complications
Swelling
Raised ICP*
Septicaemia
Seizures
*Intracranial pressure
Meningitis: allopathic treatment
Antibiotics, antivirals, corticosteroids
Analgesics, antipyretics (to lower temperature)
Intravenous fluids
Concussion: definition
Temporary loss of neuronal function
Concussion: aetiology
Significant blow to the head
Concussion: signs and symptoms
Loss of consciousness
Memory loss of events surrounding the injury
Headache
Disorientation
Nausea/vomiting
Concussion: allopathic treatment
Rest
If any consciousness lost, avoid any vigorous activity for 3 months
Cerebral Contusion: definition
Traumatic brain injury that causes bruising of the brain with ruptured blood vessels and oedema
Cerebral Contusion: aetiology
Blunt blow to the head
Cerebral Contusion: signs and symptoms
Headache Confusion Dizziness Loss of consciousness Nausea Vomiting Seizures Difficulty with co-ordination/movement Impaired memory, vision, speech, hearing
Cerebral Contusion: allopathic treatment
Medical emergency