Neuro Emergencies

Question 1

Status epilepticus- def and management

Answer 1

Status epilepticus: ≥ 5 min clinical or electrographic seizure activity OR
≥2 seizures without recovery in between

Refractory status epilepticus: failure of benzodiazepine + 1 ASM occurs in 30%
of SE patients, 30% die

Rapid management:
-Airway: oral airway, lateral decubitus, suction, rapid sequence intubation
- Breathing: bag mask, 100% O2, saturation probe, RT
- Circulation: cardiac monitor, IV/IO access (≥2 IVs)
- Fever: antipyretics, cooling, antibiotics
- CHECK CAPILLARY GLUCOSE!à thiamine 100 mg IV, D50 (50 mL IV)

1 Abortive + 1 Maintenance

Abortive therapy: Treat early with effective doses!
-Lorazepam 0.1 mg/kg IV OR 4 mg IV over 2 min, repeat 4 mg IV after 4 min
-Midazolam 10 mg IM/buccal/IN
- Diazepam 0.2mg/kg PR up to 20mg

Maintenance therapy
-Phenytoin 20 mg/kg IV, max 50 mg/min
- Fosphenytoin 20 mg PE/kg IV, max 150 mg PE/min
- Valproic acid 40 mg/kg IV, at 10 mg/kg/min
- Levetiracetam 60 mg/kg IV, max 4500 mg over 15 min
-Lacosamide 200-400mg IV over 15 min
- Phenobarbital 20 mg/kg IV, at 50 mg/min

Question 2

Refractory Status Epilepticus- tx

Answer 2

-ICU monitoring
-Midazolam 0.2 mg/kg IV, then ≤2 mg/kg/h
-Propofol 2 mg /kg IV, then ≤10 mg/kg/h
-Aim for burst suppression for 24h before tapering

-Monitor for NCSE with continuous EEG

especially important if patient paralyzed for intubation

Question 3

Status epilepticus: Investigations

Answer 3

GLUCOSE! ↓↑
ABG/VBG (respiratory & metabolic acidosis)
Lactate↑
CBC (↑ WBC)
Electrolytes (Na ↓ K Cl CO2)
Extended Electrolytes (Ca ↓, Mg ↓, PO4↓)
Creatinine ↑
Ammonia ↑
Toxicology screen
Liver enzymes (Rx)
Antiepileptic drug level ↓ (adherence, toxicity)
Prolactin ↑ (PPV 74% NPV 54%)
Beta-hCG

CT brain (tumour, pus, blood)
MRI brain (cortical lesion)
EEG (interictal epileptiform discharges)

Question 4

Status epilepticus: Treat the cause

Answer 4

Metabolic

ØHypoglycemia: thiamine 100
mg, dextrose 50% 50mL IV
ØRestart missed antiepileptics
ØTreat withdrawal (alcohol,
benzodiazepine, barbiturate),
CIWA protocol
ØToxicity (bupropion,
imipenem, penicillins, clozapine)
ØHyponatremia
ØHypocalcemia
ØHypomagnesemia
ØEclampsia (magnesium 4g IV)
ØRenal/hepatic dysfunction

Structural

ØMeningitis
ØEncephalitis (HSV 1»2): consider
antibiotics or empiric acyclovir
ØStroke ischemic, epidural, subarachnoid,
intraparenchymal hemorrhage
ØCerebral venous thrombosis
ØHypoxic ischemic encephalopathy
ØHypertensive encephalopathy (PRES)
ØAutoimmune (limbic encephalitis e.g.
NMDA, LGI-1, GABA-B)

Question 5

Definition of Epilepsy

Answer 5

≥2 unprovoked seizures >24h apart

OR

1 unprovoked seizure with >60% recurrence risk

OR

Epilepsy syndrome

Question 6

Risk of recurrence- seizures

Answer 6

Ø-After first seizure ~21-45% risk of recurrence, greatest in first 2y
(treatment lowers 2y recurrence risk but not longterm risk)

• ≥ 60% if abnormal EEG or MRI

EEG

-Routine EEG yield is low ~30%
(50% within 24h of event)
-Serial EEGs ~70%
- Sleep deprivation ~50%

Question 7

Counselling patients with epilepsy

Answer 7

Safety: avoid climbing, swimming, driving
Ø CMA Driving Guidelines:
Ø First seizure, unprovoked: 3 months
Ø Epilepsy: 6 months seizure-free on medication
Ø Medication change: 3 months
Ø Spouse/parent to take first aid course
Ø Sudden unexpected death in epilepsy (SUDEP)
Ø Medic Alert bracelet

Nonpharmacological:
Ø Alcohol/recreational drug cessation
Ø Sleep hygiene
Ø Trigger avoidance (photosensitivity)
Ø Screen for anxiety, depression, suicidal thoughts

Question 8

Adverse effects AED

Answer 8

Ø Osteoporosis
Ø Hyponatremia: carbamazepine, oxcarbazepine, eslicarbazepine
Ø Psychiatric/irritability: levetiracetam
Ø Stevens-Johnson syndrome: phenytoin, lamotrigine,
carbamazepine, oxcarbazepine
Ø PR-prolongation: lacosamide
Ø Weight gain: valproate
Ø Weight loss: topiramate
Ø Cognitive impairment: topiramate, clobazam
Ø Sedating: clobazam, phenobarbital

Question 9

Guillain-Barré Syndrome- definition

Answer 9

Acute monophasic inflammatory demyelinating polyradiculoneuropathy causing sensory loss, ascending paralysis, and areflexia.

Risk factors:
Antecedent infection (C. jejuni ~30%, influenza, HIV, Zika)

Influenza (+1 case per 60,000)&raquo_space;> flu shot (+1-2 cases per million vaccinations)

Question 10

Guillain-Barré Syndrome- tx

Answer 10

For nonambulatory patients within 4 weeks of symptoms,

Intravenous immunoglobulin (IVIg)
2g / kg divided over 2-5 days

OR

Plasmapheresis (PLEX)

Steroids are NOT recommended in GBS.
No role for sequential or repeat IVIg treatments

ABCs
Telemetry, BP, FVC q4h
Elective intubation if:
FVC < 20mL/kg
MIP 0 to –30 cm H2O
MEP < 40 cm H2O

Question 11

Predictors of respiratory failure
in Guillain-Barré Syndrome

Answer 11

Onset to admission <7d
FVC < 60% normal predicted
Presence of facial weakness
Inability to cough
Inability to lift the head
Inability to lift the arms
Inability to stand

Question 12

Investigations in Guillain-Barré Syndrome

Answer 12

Ø FVC
Ø Post-void residual
Ø MRI whole spine + Gad
– Nerve roots & cauda equina may
enhance, also r/o acute myelopathy
(mimic)
Ø CBC, electrolytes, BUN, Cr,
INR/PTT

Ø LP for albuminocytologic dissociation
– Protein >0.45 + WBC <5 seen in 50% by 1st week,
75% by 3rd week.
– Protein usually between 0.45-2
– WBC 5-50 in 15% of GBS cases
– If ↑WBC, check HIV status.

Ø EMG/NCS to look for absent F waves,
conduction blocks
– Most sensitive 2 weeks post-symptom onset

Ø ± Anti-Gq1b antibodies (Miller Fisher
syndrome)

Question 13

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)

Answer 13

Clinical features: Progressive
symmetrical proximal and distal
weakness, large fibre sensory loss,
areflexia, fatigue over 2 months

-Usually sparing cranial nerves,
autonomic, respiratory muscles

Ø Diagnostic evaluation:,
Ø EMG/NCS: acquired demyelination
Ø HbA1C, CBC, electrolytes, liver, renal, thyroid function, B12,
methylmalonic acid, SPEP, UPEP, immunofixation, free light
chains
Ø ±LP: albuminocytologic dissociation
Ø ±MRI spine + Gad: enhancing nerve roots, plexus, peripheral
nerves
Ø ±Nerve ultrasound: focal enlargement

Treatment:
Ø maintenance IVIg 1g/kg q3wk or SCIg
Ø prednisone 1mg/kg
Ø Prognosis: variable: 25% completely remit,
50% assistive gait devices, 10% permanently disabled

Question 14

When to suspect a treatable neuropathy

Answer 14

Typical pattern:
Distal symmetric polyneuropathy
1. Paresthesias migrate from feet to legs,
leaving wake of numbness (cardboard)
2. Loss of ankle reflexes
3. ↓ sweating in feet
4. Atrophy of extensor digitorum brevis
5. Toe flexor/extensor weakness
6. Paresthesias at knees -fingertips

Red flags:
ØSignificant asymmetry
ØAcute onset
ØEarly motor involvement
ØSignificant autonomic
involvement
(orthostasis, sexual dysfunction, gastroparesis)

Question 15

Myasthenia Gravis- def and inv

Answer 15

Autoimmune destruction of the postsynaptic neuromuscular junction
Bimodal age of onset: young women 20s, older men 60s

Fatiguable weakness primarily of
Ocular: ptosis, binocular diplopia, pupil-sparing
Bulbar: dysarthria, dysphagia, chewing fatigue, head drop
Respiratory: orthopnea
Extremities: proximal > distal weakness, and intense fatigue

Investigations

ØFVC/PFTs
ØSerum AChR Ab (±MuSK, LRP4): 80% generalized MG, 50% ocular MG

ØEMG/NCS
-SFEMG: Single-fibre EMG of frontalis, orbicularis oculi for enhanced jitter (Sn 95%,
nonspecific)
-RNS: Repetitive nerve stimulation for decrement (Sn75% Sp 90%)

ØCT chest to r/o thymoma (10% MG pts)
ØCBC, electrolytes, Cr
ØTSH, CK

Question 16

Acute management of myasthenic crisis

Answer 16

ABCs

Elective intubation if:
FVC < 20 mL/kg
MIP 0 to –30 cm H2O
MEP < 40 cm H2O

Plasmapheresis (PLEX)
Preferred by consensus opinion for rapidity of action

OR

Intravenous immunoglobulin (IVIG)

2g/kg over 2-5d

Hold pyridostigmine when intubated (manage airway secretions)

High-dose prednisone CAUTION!
<50% transient worsening of respiratory status in 5-10d

Question 17

Maintenance treatment of myasthenia gravis

Answer 17

Symptomatic:
Pyridostigmine 60mg po TID

ADVERSE EFFECTS
GI upset, bronchorrhea, cholinergic crisis

Disease Modifying Therapy:
Prednisone (lowest efficacious dose) Psychosis, hyperglycemia, wt gain,
bruising, osteoporosis

Azathioprine ↓WBC, ↑ transaminases

Plasmapheresis (PLEX) Hypogammaglobulinemia, hypocalcemia,
arrhythmia, anaphylaxis

IVIg Aseptic meningitis, thromboembolism,
AKI, anaphylaxis if ↓ IgA

Eculizumab Meningococcal infection
Rituximab Infusion reactions, opportunistic infections (PCP, PML, cryptococcal)

Efgartigmod URI, neutropenia

Immune checkpoint inhibitor induced myasthenia gravis and
myositis is treated with methylprednisolone, contrary to usual
myasthenic crisis, where plasmapheresis and IVIg are preferred.

Question 18

Role of thymectomy in myasthenia gravis

Answer 18

Thymoma + (10%): Refer to thoracic surgery for thymectomy

Thymoma -: Elective thymectomy if:

Ø <60 years
ØAChRAb+
ØDisease duration <5y

Question 19

Secondary headaches

Answer 19

Vascular
Ischemic stroke/venous thrombosis
Hemorrhage (ICH, SAH, SDH, EDH)
Dissection (carotid/vertebral)
Giant cell arteritis
Reversible cerebral vasoconstriction
syndrome (RCVS)
Posterior reversible encephalopathy
syndrome (PRES)
Pituitary apoplexy
Arterial-venous malformation

Space-occupying
Tumour
Hydrocephalus
Idiopathic intracranial hypertension
Infectious
Meningitis/Encephalitis/Abscess
Sinusitis/Otitis

Ophthalmologic
Acute glaucoma
Iritis
Optic neuritis

Question 20

Red flags in headache: SNOOP4

Answer 20

Systemic: fever, weight loss, immunosuppression (HIV, steroids, cancer, pregnancy)

Neurological symptoms/signs (meningismus, encephalopathy, papilledema)

Onset thunderclap: peaks <1min

Older > 50y

Pattern Δ, Positional, Pulsatile tinnitus, Precipitated by cough or Valsalva

Question 21

Investigation of secondary headache

Answer 21

ØCT/CTA/CTV head & neck
ر MRI brain

Ø CBC, electrolytes, creatinine
Ø ± ESR, CRP for GCA (Sn 85%, Sp 30%)
Ø ± D-dimer for CVT (Sn 97.8 %, Sp 84.9 %)
Ø ± blood cultures for infective endocarditis
(beware all fever + stroke-like deficit)
Ø ± lumbar puncture (SAH/meningitis)

Question 22

Diagnosis of migraine without aura

Answer 22

≥ 5 headache attacks lasting 4-72h with no better explanation

2 of:
Ø Unilateral location
Ø Pulsating quality
Ø Moderate or severe pain intensity
Ø Aggravation by or causing
avoidance of routine physical
activity (e.g. walking or climbing
stairs)

1 of:
ØNausea/vomiting
ØPhotophobia and phonophobia

Question 23

Multiple sclerosis: Typical syndromes

Answer 23

Optic neuritis: painful eye movements, monocular vision
& colour loss or scotoma, RAPD, 1/3 mild disc swelling

Brainstem/Cerebellar syndrome: bilateral INO, diplopia,
dysarthria, ataxia, gaze-evoked nystagmus, vertigo, facial
numbness, 6th nerve palsy

Incomplete transverse myelitis: sensory loss, asymmetric
limb weakness, urge incontinence, erectile dysfunction,
Lhermitte (neck flexionà spinal electric shock sensation)

Uhthoff phenomenon (heat exacerbation)

Question 24

Revised Macdonald criteria for RRMS 2017

Answer 24

-MS is the most likely diagnosis AND
-1 clinical attack (CIS) AND
-Dissemination in space (DIS) and in time (DIT)

DIS
-≥2 clinical attacks OR
-≥2 lesions in ≥2 of
cortical/juxtacortical,
periventricular,
infratentorial, or
spinal cord

DIT
- ≥2 clinical attacks OR

• MRI: Gad-enhancing and non-
  enhancing lesions OR

-2 MRIs: new T2 or Gad lesion on
follow-up scan OR

-CSF-specific oligoclonal bands

Question 25

Investigations MS

Answer 25

ØMRI brain and cervical-thoracic
spine with gadolinium

ر LP for oligoclonal bands,
IgG index

Ø CBC, Cr, liver enzymes, SPEP
Ø B12, TSH
Ø ± Visual evoked potentials
Ø ± NMO/MOG antibody
Ø ± ANA, ESR, CRP, ENA, ACE, ANCA
Ø ± VDRL, Lyme, HIV, HTLV

Question 26

Treating MS attacks

Answer 26

ØIf functionally disabling, high dose corticosteroid can speed recovery
Ø Used in optic neuritis, motor weakness; not mild sensory symptoms
ØDoes not alter degree of recovery
ØDoes not reduce future attack risk

Methylprednisolone 1000 mg IV daily for 3-7 days ± taper

Alternative: PO steroid appears equally effective (COPOUSEP trial), e.g. prednisone 1250 mg for 3-7 days ± taper
However: Optic Neuritis Treatment Trial (ONTT) suggested greater recurrence of ON in oral group.

Plasmapheresis
If poor steroid response

Question 27

Disease-modifying therapy in RRMS

Answer 27

-Decrease RRMS relapse rate
- Decelerate MRI brain lesion accumulation
- Lower risk of conversion to SPMS

Ø Injections: beta-interferon, glatiramer acetate
Ø Oral agents: dimethyl fumarate, teriflunomide, fingolimod, siponimod, cladribine
Ø Infusions: natalizumab, alemtuzumab, ocrelizumab
Ø Hematopoietic stem cell transplant

Lifestyle
Ø Physical activity
Ø Smoking cessation
Ø Vitamin D 4000 IU daily

Question 28

Acute management of encephalopathy

Answer 28

Emergent Treatments
Ø ABCs
Ø Thiamine, dextrose, ± Naloxone (0.4 to 2
mg IV)
Ø Hyperthermia: cooling blankets,
antipyretics
Ø Consider empiric antibiotics/antivirals:
ceftriaxone 2 g IV q12h, vancomycin
15mg/kg IV q8h, ampicillin 2g IV q4h,
acyclovir 10 mg/kg IV q8h

Rapid investigations
Ø CBC, electrolytes, BUN, creatinine,
glucose, ABG, osmolality, liver enzymes,
NH3, bilirubin, albumin, INR, PTT,
toxicology,
Ø ± TSH, B12, cortisol
Ø CT/CTA head and neck
Ø MRI brain
Ø EEG (Mild ↓α, moderate θ, profound δ)
Ø Lumbar puncture

Question 29

Herpes encephalitis

Answer 29

Most common fatal sporadic encephalitis

Pathophysiology
HSV1 reactivation along face to trigeminal
ganglia around medial temporal lobes

Clinical presentation
<1 week altered mentation, aphasia, ataxia,
memory impairment, or focal seizures

Investigations
Ø MRI brain
Ø Lumbar puncture: ↑ RBC, ↑Lymphocytes, Glucose
Normal
Ø EEG: high amplitude slow waves (delta and theta
slowing), occasionally lateralized periodic discharges
Ø HSV CSF PCR: Sn 98% Sp >94% for 2 weeks

Prognosis
Ø Untreated mortality 70%
Ø Survivors usually disabled: 67% have residual deficits
Ø Associated with later development of anti-NMDAR
encephalitis (psychiatric changes, dyskinesias,
autonomic instability)

Question 30

Autoimmune encephalitis

Answer 30

Clinical presentation
Ø Prodromal headache, fever, flulike
illness then over weeks:
Ø Psychiatric changes (anxiety, irritability,
psychosis)
Ø Movement disorders (orofacial
movements, dystonia, chorea)
Ø Sleep disorder
Ø Dysautonomia (hyperthermia,
hypoventilation, arrhythmias)

Investigations
Ø MRI brain + Gad
Ø EEG
Ø Lumbar puncture, HSV1&2/VZV, oligoclonal
bands, bacterial/fungal cultures, cytology
Ø Serum & CSF encephalitis antibodies (London
Health Sciences Centre)

Treatment
Ø Immunotherapy:
Ø Screening for malignancy: CT TAP,
testicular/pelvic ultrasound, PET

Question 31

Lateral medullary syndrome (Wallenberg)

Answer 31

Infarction of vertebral or posterior inferior cerebellar artery (PICA)

Clinical features
Ø Vertigo, nausea, vomiting
Ø Ipsilateral Horner syndrome
Ø Ipsilateral face & contralateral body
pain/temperature loss
Ø Ipsilateral cerebellar ataxia
Ø Ipsilateral dysphagia/dysarthria
Ø Hiccups
Ø N.B. No limb weakness!

Question 32

Intracranial hypertension

Answer 32

ICP ≥20 mmHg (Normal ≤ 15)

Clinical presentation
Ø Headache, sometimes thunderclap
Ø Emesis
Ø Papilledema, dilated pupil, CN VI palsy
Ø Drowsiness

Pathophysiology
Ø Intracranial mass (tumour, abscess, hemorrhage)
Ø Cerebral edema (infarct, hypoxic-ischemic, TBI)
Ø Increased CSF production (choroid plexus papilloma)
Ø Decreased CSF absorption or obstructed outflow
(post-meningitis, venous sinus thrombosis, jugular
vein compression)

Investigations
Ø CT brain

Management
Ø Head of bed at 30o, maximize jugular drainage, minimize
Valsalva e.g. endotracheal suctioning
Ø Keep CPP > 60 mmHg and PO2 > 60 mmHg
Ø Intubate and hyperventilate patient PCO2 26-30 mmHg
Ø Osmotic treatments: Hypertonic saline (3% NaCl for
serum Na 145-155 mEq/L); Mannitol 20% (1 g/kg then
0.5 g/kg q6h prn); Serum osmolality >280 mOsm/L
Ø Neurosurgery: External ventricular drain (EVD),
Ventriculoperitoneal shunt (VP shunt), Endoscopic 3rd
ventriculostomy, decompressive hemicraniectomy
Ø Antiseizure medication if seizures suspected
Ø Dexamethasone 10mg IV x 1, then 8 mg bid if vasogenic
edema from mass lesion