Bleeds in the brain - EDH, SDH, SAH, ICH, DAI

Question 1

what are the 5 main types of bleeding into the brain

Answer 1

extradural
subdural
subarachnoid
intracerebral
(diffuse axonal injury)

Question 2

what does each type of bleed look like on a CT scan

Answer 2

ED - lens shape

SD - ellipse shape (banana)

SA - best seen around circle of willis, dense grey outline

IC - lump of blood somewhere in the brain (common in basal ganglia/thalamus area

diffuse axonal injury - brain looks “fuzzy”, loss of distinction between grey/white matter

Question 3

how does blood show up on a CT

Answer 3

acute blood - white
old blood - black
actively bleed site - dusk sign, grey

Question 4

what type of bleed is an EDH and how does it occur

Answer 4

high pressure arterial bleed

high force mechanism of injury

• dura firmly attached to the bone
• small arteries run through this space
• when force shears the dura away from the bone these arteries bleed

Question 5

what area/vessel is most at risk of an EDH

Answer 5

temple area - pterion is weak

middle meningeal artery at risk

Question 6

what is the general presentation/progression of a patient with an EDH

Answer 6

concussed
then appears well
bleed continues (high pressure arterial)
patient worsens when space expands between bone and dura - starts pushing into brain

Question 7

what is the management of an EDH

Answer 7

emergency - burr hole or small craniotomy to remove blood/release pressure
early detection = better recovery

Question 8

what type of bleed is a SDH and how does it occur

Answer 8

low pressure venous bleed

small trauma mechanism

• veins go between dura and arachnoid layers (subdural space)
• stretching/increased pressure across these veins lead to tears
• bleeds

Question 9

what is the general presentation/progression of a patient with a SDH

Answer 9

small trauma (patient might not even notice it) causes bleed - takes a long time to present clinically
might have multiple bleeds before getting noticeable signs/symptoms
on CT can show “acute on chronic SDH” from multiple small traumas over time

Question 10

who is at risk of a SDH

Answer 10

people with atrophy of the brain
eg elderly, dementia, alcoholics

atrophy of the brain leads to stretching of the veins within subdural space - increases likelihood of ruptures

Question 11

what is the treatment of a SDH

Answer 11

if big can drain with a burr hole

if large and old can insert two small holes and do a wash out of broken down blood

Question 12

what type of bleed is a SAH and how does it occur

Answer 12

high pressure arterial bleed

can occur from head injury or spontaneous aneurysm

• bleeding between the arachnoid and pia
• blood accumulates in the SA space around the curvatures of the brain

one type of haemorrhagic stroke

Question 13

what is the general presentation/progression of a patient with a SAH

Answer 13

*sudden onset thunderclap headache
N/V
meningism (irritation of the meninges) - headache, neck stiffness, photosensitivity

Question 14

what are some causes and risk factors of a SAH

Answer 14

trauma
aneurysm (more common in younger patients)

HTN
polycystic kidney disease
smoking
alcohol
cocaine use

Question 15

where is the most common place for an aneurysm

Answer 15

where the arteries bifurcate eg anterior communicating artery in the circle of willis

Question 16

what are the investigations and management of a SAH

Answer 16

CT head within 6 hours of onset
CT angiogram
MRI

investigations guide management

• lower BP eg labetalol
• prevent vasospasm eg CaCB (nimodipine) for 21 days
• coiling (intravascular) to prevent bleeding

reduce risk factors

Question 17

what are some complications of a SAH

Answer 17

hydrocephalus - needs a shunt to drain

vasospasm - can lead to ischaemic stroke

Question 18

what type of bleed is an ICH

Answer 18

high pressure arterial bleed

one type of haemorrhagic stroke
- ie bleeding into the brain

Question 19

where is it most common for an ICH to occur

Answer 19

thalamus and basal ganglia

Question 20

what are risk factors for an ICH

Answer 20

HTN
anticoagulants
blood thinners

Question 21

what is a complication of an ICH

Answer 21

can spread to the ventricles causing hydrocephalus

Question 22

what is the management of an ICH

Answer 22

if spread to ventricles - drain to outside
craniotomy to relieve pressure in extreme cases
antihypertensives

secondary prevention to control BP

Question 23

what is a diffuse axonal injury

Answer 23

shearing of tiny vessel between the white an grey matter - leads to petechial haemorrhage

Question 24

how does a DAI occur

Answer 24

high velocity impact
shaken head (paeds - “shaken baby”)
white matter and grey matter have different densities
- one moves faster than the other
- axons crossing between the two break
- very tine blood vessels break
- widespread petechial haemorrhage on top of multiple white and grey matter lesions

causes LOTS of swelling - can be very difficult to treat

Question 25

what complications can a DAI lead to

Answer 25

increased pressure on the brain due to extensive swelling throughout

• can lead to brainstem herniation as its pushed down through the foramen magnum
• can cause ischaemia and pressure damage
• common cause of persistent vegetative state

Question 26

what is a normal value for ICP and when should you start to worry

Answer 26

~10 normal

>20 worry

Question 27

what regulates the ICP

Answer 27

systolic BP - cerebro autoregulation can maintain a normal ICP between systole 50-150
outside of this auto regulation fails = symptoms

Question 28

what can cause raised ICP and therefore autoregulation to be put off

Answer 28

anything that raises pressure

• bleeding
• mass/tumours/cysts
• oedema

Question 29

DAI management

Answer 29

very difficult - try reduce raised ICP from swelling, palliative