subdural haemorrhage Flashcards
what is it?
A subdural haemorrhage occurs when there is bleeding into the subdural space between the outer two layers of the meninges, the dura mater and arachnoid mater. This may be acute (occurring within 3 days of injury), subacute (3-21 days after an injury) or chronic (detected over 21 days after an injury).
what is the epidemiology?
severe head injury
>65 most at risk due to cerebral atrophy + weakening of bridging veins
in infants - due to NAI
other RF = bleeding disorders, anticoagulants, chronic alcoholism
what is the aetiology?
from tearing of the bridging cortical veins that drain blood from the cortex to the venous sinuses.
the collection of blood initially clots, then liquifies before disintegrating into serous fluid.
what are the features?
headache
n+v
confusion
anorexia
drowsiness
personality changes
seizures
Decreased level of consciousness
Focal neurological deficits e.g. limb weakness
Dysphasia
Signs of raised intracranial pressure in large SDHs e.g. bradycardia, hypertension and irregular breathing (Cushing’s triad)
what are the differentials?
extradural haemorrhage - usually acute onset, lucid intervals
stroke - focal neurological signs
migraine - photophobia, aura etc
subarachnoid - sudden onset headache, due to aneurysm rupture?
space occupying lesions - CT differentiates
what are the ix?
CT - diagnostic
crescent shaped extra axial collection
large SDH show midline shift
how do SDHs appear on CT based on time period?
acute SDH - hyperdense
subacute SDH - isodense
chronic SDH - hypodense
what is the conservative mx?
Take an A to E approach; airway support with intubation and ventilation may be required for unconscious patients
In a trauma scenario, ensure the C-spine is protected
Urgent neurosurgical referral
Small SDHs with no midline shift or neurological impairment may be managed conservatively with neuro-observations and serial CT head scans for monitoring
what is the medical mx?
Reverse any anticoagulation, significant thrombocytopenia or clotting abnormalities
Ensure adequate analgesia is given for pain
Antiemetics may be required for nausea and vomiting
Medical treatment for raised intracranial pressure may be indicated (e.g. hypertonic saline)
what is the surgical mx?
Surgical management is indicated in patients with focal neurological deficits, raised intracranial pressure, midline shift, large haematomas or deteriorating patients
In acute SDHs, urgent craniotomy is usually the first line method of evacuating the collection
Subacute or chronic SDHs can usually be evacuated via burr hole craniotomy as the liquefied blood can be removed more easily; a drain may be placed to reduce recurrence rates
Embolisation of the middle meningeal artery is a developing option in some patients with chronic SDHs
what are the complications?
Recurrent haematoma formation
Raised intracranial pressure leading to herniation of the brain
Cerebral oedema
Seizures
Neurological deficits e.g. paralysis of a limb
Cognitive impairment
Death
