Neurosciences Flashcards
Clipping vs coiling aneurysmal SAH
ISAT 2005
coiling better short term outcomes, less invasive
coiling may require repeat procedures
less dependency and death at 1 year with coiling but higher rebleeding
surgical clipping - wide neck
improving coiling techniques
ICU management SAH
- allow HTN first 21 days once porected
- MAP > 90
- ICP < 20 CPP > 60
- treat seizures (avoid prophylaxis - worse outcomes)
- repeat CT if change
- feed
- thromboprphylaxis
DCI vs vasospasm
vasospasm = narrowing of blood vessels
DCI = new neurological deterioration, may be due to basospasm
DCI management
- nimodipine
- euvolaemia, avoid anaemia
- end-vascular - coiling, angioplasty, IR vasodilator
HHH - hypertension, hypervolaemia, haemodilution - no longer recommended
Primary brain injury
neuronal dammage occurring immediately as a direct result of initial trauma. it is irreversible
impact - head striking object
inertial loading - he’d moving rapidly back / forward
penetrating
blast
Types of TBI
Fracture
- simple skull fracture
- depressed skull fracture - more likely to tear dura
Haematoma
- EDH
- SDH
- intraparenchymal
Other
- SAH
- Intraventricular haemorrhage
- contusion - coup / contrecoup
- diffuse axonal injury - shearing o axons
Secondary brain injury
neuronal damage due to sequelae of primary injury. hours - days after primary injury and main determent of outcome
causes
intracranial
- haematoma
- hydrocephalus
- vasopsasm
- infection
-seizures
extracrnial
- hypotension
- hyoxia
- hypo.hypercapnia
- hyponatraemia
- hypo/hyperglycaemia
- hyperthermia
Indications for CT head in head injury
- GCS < 13 on initial assessment
- GCS < 15 at 2 hrs
- Seizures
- Suspected open or depressed skull fracture
- signs of BOS fracture
- focal deficit
- > 1 vomit
ICP monitoring indications
GCS 3-8 and abnormal CT head scan
GCS 3-8 and normal CT head scan if 2 of:
- Age > 40
- SBP < 90
- Abnormal motor posturing
(GCS < 12 and sedated)
Physiological principles of preventing secondary brain injury
Maintain cerebral oxygenation
- PO2 > 10
- CPP 60-70
- treat anaemia
Reduce CMRO2
- treat seizure
- normoglycaemia
- normothermia
- deep sedation
- NMB
- barbiturate infusion
Manage increased ICP
- ICP monitoring
- Blood
- CO2 4.5 - 5
- hyperventilate if extreme
- Head up 30 degrees
- avoid tube ties
- Brain - osmotherapy
- CSF - EVD
- Decompressive craniectomy - DECRA 2011 - significant more GOSE 1-4, no difference in death
ICU management = tiers
TBI outcomes
Extended glasgow outcome scale GOSE
1 - 8
8 = upper good recovery
1 = death
CRASH 1
steroids in head injury GCS < 14
significanty higher mortality with methyprednisolone
Cooling in TBI
Eurotherm / Polar - trend to poorter outcomes, increased short term morbidity. not recommended
Intracerebral haemorrhage
Bleeding into the brain parenchyma
15% of strokes
Arterial / venous disease, vascular malformations, haemostatic disorders
precipitated by hypertension, CVST, drugs
usually deep sites - cerebellum, pions, thalamus
correction of coagulopathy
intensive BP reduction to 140 systolic (jay prevent haematoma enlargement, end organ dysfunction from hypertension however may reduce cerebral blood flow
BAMFORD classification ischaemic stroke
TACS - all 3
- unilateral motor / sensory / both deficit
- homonymous hemianopia
- higher cerebral dysfunction
PACS - 2 out of 3
LACS
- pure motor / sensory face/arm/leg
- sensorimotor deficit
- dysarthria
- acute movement disorder
POCS
- isolate hemianopia
- brainstem signs
- cerebellar ataxia
Investigation of ischaemic stroke
validated tool for diagnosis e.g. rosier
exclude hypoglycaemia
history - onset, anticoagulation
NIHSS
Non-contrast CT
CTA if thrombectomy indicated
Perfusion scan if thrombectomy > 6hrs
risk factors - HBA1c, lipid profile, ECG
Management priorities ischaemic stroke
supportive care - O2
BP < 185/110 if thrombolysis
consider reduction if > 220/120 or organ dysfunction
aspirin 300mg 2 weeks
thrombolysis < 4.5hr
stroke ward
contraindications to thrombolysis
- active bleeding
- BP > 185/110
- recent surgery
- DOAC last 48hr, INR > 1.7, platelet < 100
- ischemic stroke < 3 mo
- intracranial malignancy
- previous ICH
Malignant MCA syndrome
rapid neurological deterioration due to cerebral oedema following MCA territory stroke
inconclusive evidence of decompressive craniectomy
NICE
- MCA infarction NIHSS > 15
- reduced consciousness
- CT infarct > 50% MCA territory
CVST
Superior saggital, transverse, internal jugular, cortical veins
Risk factors
- those for thrombotic disorders plus
- head injury
- LP
- IJV CVCC
CVST pathophysiology
venous congestion upstream of occlusion
fluid extravasation into parenchyma
if venous pressure > arterial pressure ischaemia
CSF obstruction from swelling
CVST features
Headache - new, diffuse, severe, progressive
- seizures, paresis, papilloedema, altered mental state
- signs and symptoms of raised ICP
- focal neurology - visual disturbance
Consciousness
state of wakefulness and awareness
- wakefulness = eyes open, degree of motor arousal
- awareness - the ability to have experience of any kind
Disorders of consciousness
Confusional state - confusion, disorientation
Minimally conscious state
- plus - higher level responses e.g. following commands
- minus - lower level responses e.g. localising
vegetative state - reflexive and spontaneous movements only
- coma
Disorders of consciousness vs BSD
BSD = no wakefulness, no awareness, no consciousness. irreversible
coma = no wakefulness, no awareness, no consciousness. no response to environment or stimulation
VS = wakefulness but no consciousness or awareness
MCS = wakefulness, awareness and consciousness
Locked in syndrome
upper motor neurone quadriplegia affected cranial nerves
brain stem pathology
consciousness maintained
usually preserves eye movements in 1 or 2 axes
Prolonged disorders of consciousness
> 4 weeks
permanent if no change in trajectory for 6 months
- cause established
- not related to medictions
- reversible causes of loss of awareness treated
- exclusion of other potentially reversible causes
- coma recovery scale
longer someone in APDOC, lesss likely to regain consciousness
Long term management of PDOC
- clinically assisted nutrition and hydration
- pressure area relief
- physiotherapy - prevent joint stiffnes
- washing
- bladder / bowel management
Usually fully dependent
MDT / court involvement in withdrawing nutrition and hydration
