Neurology Flashcards
Ischemic Stroke
Indications for clot retrieval:
- Ischaemic stroke on CT perfusion (no ICH)
- large-vessel occlusion on CT Angiogram (clot in ICA or proximal MCA)
- substantial neurological deficit NIHSS>5
- ASPECT score >5
- Onset of symptoms < 24 hours
- Functionally independent prior to stroke (Modified Rankin score 0-1)
CT FINDINGS SUPPORTING URGENT REPERFUSION
- no intracranial haemorrhage
- evidence of a large vessel occlusion
- small ischemic core
- large ischemic penumbra
- no signs of completed stroke (oedema, loss of grey-white matter differentiation)
- No contraindications to thrombolytics ie presence of AVM/brain tumour/unsecured aneurysm >10mm
DISCUSSION AROUND CONSENT FOR THROMBOLYSIS:
- 7% risk of ICH (3% are fatal haemorrhages)
- No overall mortality benefit
- Small but significant chance of improved neurologic outcomes at 90days
CONTRAINDICATIONS FOR THROMBOLYSIS:
- Last known well time >4.5 hours
Acute ICH
Previous ICH
Ischaemic stroke <3months
Intracranial/intraspinal surgery within 3 months
GI bleeding within 21 days
Pretreatment systolic blood pressure >185 mm Hg or diastolic blood pressure >110 mm Hg despite therapy
Thrombocytopenia
Major surgery last 14 days i.e. CABG
REVERSE HAEMORRHAGE
stop alteplase infusion
IV TXA 1g IV
IV Cryoprecipitate 10units
Subarachnoid haemorrhage
OTTAWA SAH RULE:
SAH can be ruled out with 100% sensitivity with the Ottawa SAH Rule for headache evaluation.
- < 40 years of age
- without neck pain or stiffness
- without a witnessed loss of consciousness
- without onset during exertion
- without a thunderclap headache
- and without limited neck flexion
CT SCAN:
CT within 6 hours
- 100% sensitive
- >99.5% specific
sensitivity decreases with time therefore a SAH cannot be excluded with a normal CT after 6hrs
CT 6-12hrs
- 98% sensitive
91-93% at 24hrs
50% at 7days
GRADING:
World Federation of Neurosurgical Societies Scale
Grade 1: GCS 15, no motor deficit.
Grade 2: GCS 13-14 without deficit
Grade 3: GCS 13-14 with focal neurological deficit
Grade 4: GCS 7-12, with or without deficit.
Grade 5: GCS <7 , with or without deficit.
Ref: Tintinalli’s
HAEMORRHAGIC EXTENSION MANAGEMENT:
- Prepare for RSI and intubation
- Pre-oxygenate 15L NRB mask at least 3min
- Elevate head of bed 30 degrese
- Treat hypertension - hydralazine 5mg iv Q5min aim SBP 110-120
- Analgesia / pre-medication with fentanyl 100mcg iv (blunt sympathetic response with laryngeal manipulation)
- RSI with ketamine 1-2mg/kg iv and rocuronium 1.2mg/kg iv
- Apnoeic BVM - Prevent hypoxia and hypercapnoea
- Post intubation sedation with propofol and fentanyl
- BP support with noradrenaline 0.1-0.2mcg/kg/min titrate to SBP 110
- Nimodipine 60mg NGT Q4hrs - for vasospasm
- Invasive blood pressure monitoring - arterial line
- Repeat CT scan
- Urgent neurosurgical consult
- Disposition ICU
COMPLICATIONS:
neurogenic pulmonary oedema
rebleeding - usually 3-5days
vasospasm and neurological deficit
hydrocephalus & brain herniation
seizure
hyponatremia
hypercapnoeic respiratory failure
Status Epilepticus
Status epilepticus
Definitions
- >5min continuous seizure activity
- 2 or more seizures without full recovery between seizures
- Seizing on arrival to ED with history of seizing for >20min
Epidemiology:
- More common in paediatric patients (age 1-3yrs)
- Common in those with intellectual disability
Causes:
Withdrawal from anticonvulsant medication – stopping suddenly
Alcohol withdrawal
Intracerebral haemorrhage
Metabolic
- hypoglycaemia
- hyponatraemia
Drug overdose
- tricyclic antidepressants
Encephalitis/meningitis
Brain tumours
Complications:
Respiratory
- Hypoxia, hypercarbia, aspiration
Cardiovascular
- arrythmias and cardiac failure
Metabolic
- Hypoglycemia, Hyperthermia, Rhabdomyolysis
Trauma
- Head injury - occiput, Tongue lacerations, Posterior shoulder dislocation, Drowning, Fractures of the upper lumbar spine
Management:
Seek and Treat hypoglycaemia with 2ml/kg 10% dextrose
OR 25ml 50% dextrose in adults
First line agents
- Midazolam5-10mg IM/IV (0.2mg/kg)
- Diazepam 10-20mg IV over 2-5 mins (0.1-0.3mg/kg)
Second line agents
- Sodium valproate 20mg/kg up to 3g followed by infusion (avoid in pregnancy)
- Levetiracetam 40mg/kg up to 4.5g over 15 min
- Phenytoin 20mg/kg IV over 20min– need cardiac and BP monitoring
-if seizures not controlled, give a different second line agent
Third line agents
- Phenobarbitone 20mg/kg IV
- RSI and intubate with thiopentone 5mg/kg and suxamethonium 1.5mg/kg
Seek and treat complications - trauma, arrythmias, metabolic derrangements etc
Disposition ICU
Hypertensive Encephalopathy
HISTORY:
altered mental state - confused
headaches and visual disturbance - seeing stars and floaters
EXAM:
fundoscopy - retinal haemorrhages, retinal exudates, retinal oedema, papilloedema, engorged retinal veins
clonus, hyper-reflexia
MANAGEMENT:
analgesia
IV hydralazine
no more than 25% drop
