Neuro Emergencies Flashcards
Status epilepticus- def and management
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
Refractory Status Epilepticus- tx
-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
Status epilepticus: Investigations
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)
Status epilepticus: Treat the cause
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)
Definition of Epilepsy
≥2 unprovoked seizures >24h apart
OR
1 unprovoked seizure with >60% recurrence risk
OR
Epilepsy syndrome
Risk of recurrence- seizures
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%
Counselling patients with epilepsy
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
Adverse effects AED
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
Guillain-Barré Syndrome- definition
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)»_space;> flu shot (+1-2 cases per million vaccinations)
Guillain-Barré Syndrome- tx
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
Predictors of respiratory failure
in Guillain-Barré Syndrome
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
Investigations in Guillain-Barré Syndrome
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)
Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)
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
When to suspect a treatable neuropathy
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)
Myasthenia Gravis- def and inv
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
Acute management of myasthenic crisis
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
Maintenance treatment of myasthenia gravis
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.
Role of thymectomy in myasthenia gravis
Thymoma + (10%): Refer to thoracic surgery for thymectomy
Thymoma -: Elective thymectomy if:
Ø <60 years
ØAChRAb+
ØDisease duration <5y
Secondary headaches
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
Red flags in headache: SNOOP4
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
Investigation of secondary headache
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)
Diagnosis of migraine without aura
≥ 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
Multiple sclerosis: Typical syndromes
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)
Revised Macdonald criteria for RRMS 2017
-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
Investigations MS
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
Treating MS attacks
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
Disease-modifying therapy in RRMS
-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
Acute management of encephalopathy
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
Herpes encephalitis
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)
Autoimmune encephalitis
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
Lateral medullary syndrome (Wallenberg)
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!
Intracranial hypertension
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
