Neurologic Emergencies

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Neurologic Emergencies. Neurology Clerkship Ninith Kartha , M.D. Case 1. A 71 year old male presents for progressive difficulty walking Developed back pain several weeks ago Reports numbness in his legs Has been having increasing difficulty walking Physical Examination Vitals stable - PowerPoint PPT Presentation

Transcript of Neurologic Emergencies

Case 1 A 71 year old male presents for progressive difficulty

walking Developed back pain several weeks ago Reports numbness in his legs Has been having increasing difficulty walking

Physical Examination Vitals stable Normal cranial nerve findings Increased tone of the LE bilaterally with moderate LE

weakness; UE’s normal LE reflexes are brisk with upgoing toes; UE reflexes

normal Reduced sensation to all modalities to mid-abdomen Gait slow with a spastic quality & requiring assistance

Case 1Can you localize the lesion?

LocalizationCentral nervous

systemBrain

Spinal cord

Peripheral nervous system

Nerve root

Plexus

Peripheral nerve

Neuromuscular junction

Muscle

4

The most important step in neurologic localization is

differentiating a central nervous system lesion from a peripheral

nervous system lesion

LocalizationUpper motor neuron

Mildly reduced bulk

Increased tone

Mild/moderate weakness

Hyper-reflexia & pathologic responses

Lower motor neuron

Severely reduced bulk with fasciculations

Reduced tone

Severe weakness

Hypotonia

5

Grading muscle power5: Full strength4: Movement against some resistance3: Movement against gravity only2: Movement with gravity eliminated1: Flicker or trace contraction0: No contraction

Grading reflexes4: Hyper with pathologic responses 3: Hyperactive2: Normal1: Diminished0: Absent

LocalizationSpinal levels

S1/2S1/2

L3/4L3/4

C5/6C5/6

C7/8C7/8Its easy to Its easy to

remember…1/2, remember…1/2, 3/4, 5/6, 7/83/4, 5/6, 7/8 ALWAYS ABNORMAL:

Asymmetric reflexes

Pathologic responses (Babinski, clonus = CNS)

Absent reflexes (PNS)6

Case 11. What studies do you want to order and why?

Where does the spinal cord end?

Spinal Cord CompressionManagement

Dexamethasone (100 mg IV followed by 16 mg PO daily in divided doses)

Surgical evaluation

Radiotherapy

Differential

Metastatic disease

Epidural hematoma

Epidural abscess

Vertebral collapse (2’ malignancy)

Aortic dissection

Case 2 28 year old male presents for progressive difficulty

walking “Stomach flu” 2 weeks ago Recently developed low back pain and paresthesias in

his feet Has been having difficulty standing, climbing stairs, and

has been tripping frequently

Physical Examination Vitals stable Cranial nerves normal Tone is relatively reduced; There is mild weakness of

bilateral ankle dorsiflexion with normal muscle bulk Distal sensation is reduced to all modalities but normal

in the trunk Reflexes are reduced throughout There is a mild bilateral foot drop

Case 2Can you localize the lesion?

LocalizationCentral nervous

systemBrain

Spinal cord

Peripheral nervous system

Nerve root

Plexus

Peripheral nerve

Neuromuscular junction

Muscle

13

The most important step in neurologic localization is

differentiating a central nervous system lesion from a peripheral

nervous system lesion

Localization

REFLEX ARC

Case 21. What studies do you want to order and why?

What else do you need to get the above done?

Test ResultsCSF Analysis

WBC 2

RBC 0

Protein 103 (15-45)

Glucose 50

Coags and platelets WNL

EMG/NCV

Conduction block

Guillain-Barre Syndrome

Clinical FeaturesTypically follows an

infectious process (2/3rds of pts) C. jejuni, CMV, EBV, M.

pneumoniaePresents with

numbness & tingling in the feet that ascends Pain the back & limbs

is commonWeakness follows

sensory disturbances

Areflexia Bowel & bladder are

usually spared Autonomic dysfunctionSymptoms should not

proceed >8 weeks 98% of pts achieve

“plateau phase” by 4 weeks

Duration of “plateau” 12 days

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Ancillary studiesAlbuminocytological dissociation with elevated

CSF protein with no or a few mononuclear cellsMay be normal in the first week If WBC count >10 think about Lyme, HIV, sarcoidosis

Antiganglioside antibodiesGM1 Abs (correlate with C. jejuni infection)GQ1b associated with C. Miller Fisher variant (ataxia,

areflexia & ophthalmoparesis)

Electrophysiologic data (EMG/NCV)Temporal dispersion, prolonged F-wave latencies,

conduction block & demyelinating range slowing18

Guillain-Barré syndromeGuillain-Barré syndrome

Guillain-Barré syndrome: Subtypes

AIDP Most common type

AMAN 10%-20% of

caseprogressive weakness often with respiratory s

Rapidly failure DTRs can be preserved or

exaggerated! 75% positive for C. jejuni

(vs. 42% in AIDP) GM1, GD1a, GD1b Abs

AMSAN Possibly the most severe

form with slow and/or incomplete recovery

Miller-Fisher variant Ataxia, areflexia,

ophthalmoplegia GQ1b Abs in almost all

patients

Pure sensory

Pure dysautonomic CV involvement is the

most common

Pharyngeal-brachial-cervical GT1a Abs May mimic MG

Paraparetic

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IVIG (0.4g/kg/day for 5 days) is at least effective as plasma exchange without some side effectsShould be started within 2 weeks Inconclusive data that IVIg has a higher relapse

rate

Corticosteroids have not been shown to be beneficial

Intubation criteria:VC <15-20 mL/kg (oe <30% baseline)PO2<70 mmHgOropharyngeal weakness20

TreatmentTreatment

GBS vs ATM

Case 1A 27 year old female presents to the ER by her

husband for “sudden onset of confusion” The patient is not following commands and is not

talking

Physical Examination She was unable to answer any questions, follow

commands, repeat, or produce spontaneous language

She had right lower facial weakness She had right arm weakness She had decreased sensation over her right arm

and face

Case 3Can you localize the

lesion? Central nervous

system, left hemisphere

The patient has right sided weakness and aphasia, which is highly suggestive of a left hemispheric stroke.

QuestionsWhat helps differentiate cortical from subcortical?

Cortical lesions can be associated with multimodal motor and sensory deficits, such as aphasia and apraxia

White matter lesions (subcortical lesions) usually cause weakness, spasticity, pure motor syndromes…but not aphasia, apraxia, etc.

Stroke: Subcortical strokes

Caused by occlusion of small (0.5-15.0 mm) penetrating branches of cerebral arteries

Chronic HTN>DM>emboli

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Syndrome Presentation LocalizationPure Motor Face, arm, leg Internal capsule

Pure Sensory Face, arm, leg Thalamus

Sensorimotor Face, arm, leg Thalamocapsular

Ataxic-hemiparesis

Hemi-ataxia & hemiparesis

Basis pontis

Clumsy hand dysarthria

Dysathria, incoordination

Genu of the IC

Acute stroke syndrome

A-B-C’s NPO, intubate for

inadequate airway, ventilate if needed

Correct hypotension, rule out acute MI or arrhythmia (a-fib)

Rule out hypoglycemia Blood glucose is between 50 Blood glucose is between 50

and 400 mg/dland 400 mg/dl

Minimize hyperglycemia by running an IV of 0.9% normal saline initially at a TKO rate

Use parenteral antihypertensive Tx only for sustained, very high BP (>220/120; or >185/110 for IV tPA) BP maintained under 185/110BP maintained under 185/110

IV tPA must be/may be given within 4.5 hrs of stroke onset

Neuro deficit (NIHSS score 5 Neuro deficit (NIHSS score 5 to 22) must not be rapidly to 22) must not be rapidly improving (TIA) or post-ictalimproving (TIA) or post-ictal

Normal PTT, PTNormal PTT, PT<<15 sec, 15 sec, platelets platelets >>100,000100,000

No bleeding, recent surgery, No bleeding, recent surgery, MI, arterial puncture or LPMI, arterial puncture or LP

No blood, or edema/infarct > No blood, or edema/infarct > 1/3 of MCA territory on CT1/3 of MCA territory on CT

TIME IS BRAIN!!!

Clinical HistoryWhat imaging test do you want to order?

CT scanCT scan in deteriorating patient, quickly rules out hemorrhage, in deteriorating patient, quickly rules out hemorrhage,

mass (tumor, abscess) or early infarct edemamass (tumor, abscess) or early infarct edema shows cortical infarcts by 1-2 days, may miss lacunar shows cortical infarcts by 1-2 days, may miss lacunar

infarctsinfarcts

MRI scanMRI scan highest resolution scan, but longer scanning timehighest resolution scan, but longer scanning time DWI (diffusion weighted imaging) detects impaired DWI (diffusion weighted imaging) detects impaired

movement of water in infarct immediatelymovement of water in infarct immediately non-invasively view arterial supply (MRA)non-invasively view arterial supply (MRA) contraindications: pacemakercontraindications: pacemaker

Non Infused Head CT

Non Infused Head CTWhat is your impression of the head CT?

The CT shows loss of gray-white junction and effacement of the sulci throughout the left hemisphere, suggestive of a stroke

EvaluationBased on the patient’s history, physical exam

findings, and CT scan, she was taken to Interventional Radiology for a cerebral angiogram…

Cerebral Angiogram

Angiogram

MCA MCA occlusionocclusion

Clinical HistoryThe patient received intra-arterial t-PA.

Following the procedure, she was transferred to the Neuro-ICU for observation and management. A follow-up MRI was obtained later…

MRI (Diffusion Weighted Image)

QuestionsWhat do you think this patient’s long-term

outcome was? The patient presented within 3 hours of the onset

of symptoms. She received intra-arterial t-PA which was effective in breaking the clot and re-establishing flow to the left hemisphere. She was speaking English by the end of the day…and French (her second language) the next day. Because her symptoms were recognized quickly and action was taken, her injury was limited.

Cerebral Angiogram Post t-PA

Pre tPAPre tPA Post tPAPost tPA

QuestionBy the time everything was done, it was 4:15 in

the afternoon on a Friday. You have time to order one test that might change your management that night….what would you order (ie, what would you be looking for that would have caused her stroke?)

QuestionAnswer….

Lower extremity venous doppler to look for the presence of a deep vein thrombosis (some people would argue for an echo…)

The patient was found to have a DVT and received an IVC filter.

How did a blood clot in her leg get into her left middle cerebral artery? She had a patent foramen ovale (upwards of 30%

of the population do)

Case 4 A 34 year old female presents to the ER with

complaint of eyelid drooping Started about one weak ago following an ER; she was

given steroids for an asthma exacerbation and ciprofloxacin for an asymptomatic UTI

Has felt “weak all over” and has been getting progressively short of breath

Physical Examination Speech is soft with a nasal quality There is fluctuating bilateral ptosis, pupils are equal

and reactive, she has a “snarl” smile Normal bulk/tone; strength can be overcome after

<60s of effort Normal reflexes, normal sensory examination Gait normal, but cannot stand up 10 times

consecutively

Case 4Can you localize the lesion

Peripheral NS

The PNS generally includes The nerve cell bodies The peripheral nerves

RootsPlexusNerve

The neuromuscular junctions (NMJs)

The muscles

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LocalizationNMJ

Fluctuating weakness (pre- and post-synaptic)

Normal bulk and tone

Normal sensory exam

Normal reflexes (usually)

Case 2How do you want to evaluate the patient?

Studies to Order/Perform Diagnostic

Ice Pack Test Improves ptosis 2° MG in 80% Local cooling slows kinetics of AChRs

Sleep TestTensilon Test

Respiratory Studies!!! BMP w/ Mg/Phos, PT/PTT, ionized calcium May need Quinton catheter placed by IR

Case 2Studies

EMG/NCS with repetitive stimulation or single fiber EMG

Chest CTThose who undergo

thymectomy are more likely to have clinical improvement, become asymptomatic or attain remission

May be less effective in those >60

Labs AChRAb

85% of pts w/ gMG and 50-60% w/ oMG test positive

MuSK antibody Striational muscle

Ab Screen for TSH, RA,

Pernicious anemia, SLE, Sarcoid, Sjogren’s, polymyositis

Case 2 Admit to ICU

Any pt w/ MG w/ questionable respiratory status should be admitted to the ICU for close monitoring

14% of pts in myasthenic crisis have some degree of arrhythmias

Respiratory 30% of pts develop respiratory muscle weakness and

crisis occurs in 15-20% Intubation Criteria/Management:

VC < 15 mL/kg Stop anti-cholinesterase medication (causes excessive

bronchial secretions and diarrhea) If needed, give pyridostigmine IV at 1/30th the oral dose

Case 2 Acute Treatment

TPE Produces impvt in 75% of pts

Long term medication Pyridostigmine 15-60 mg Q3-6

Long acting 180mg Pts w/ primarily ocular symptoms respond poorly

Corticosteroids 10-20 mg/daily initially Increase by 5-10 per week until satisfactory clinical

response or dose of 50-60/day Azathioprine

2-3 mg/kg initially (most start w/ 50 mg/d for 1 week)

Case 5A 32 year-old woman is found on the floor at

work, unconscious, but spontaneously breathing.

Physical Examination BP is 146/75, pulse 80, afebrile. There is complete left lid ptosis. Her left pupil is

5 mm and sluggishly reacts to light; the right pupil is 2 mm and briskly reacts to light.

She does not grimace or move to painful stimuli, nor attempt to speak.

Case 5Can you localize the lesion?

Evaluating the Altered Patient

1. What does the patient look like?Old?How many lines?Noisy neighbor? Jerry Springer is

blasting away and they are tangled in their call light?

Like you need to call the unit?

Evaluating the Patient2. Talk to the patient

Can they stay awake and pay attention to you? Can the patient talk to you?

How do they sound (abnormal rate, dysarthric…)Are they making any sense?

Can they tell you where they are?Patients are first disoriented to time of day, then other

aspects of time, and then to placeDisorientation to self is rare…like raise the red flag

rare

Evaluating the Patient3. Ask them to read and write

Decreased reading comprehension is characteristic of delirium

Writing disturbance is the most sensitive language abnormality in deliriumThe most salient characteristics are abnormalities in

the mechanics of writing…the formation of letters and words is indistinct, and words and sentences sprawl in different directions

Evaluating the Patient4. How does his/her breathing look?

Does it look like he/she is breathing comfortably and can protect the airway?

What does the breathing pattern look like?Rule of thumb: if breath sounds can be

heard at both lung bases and if the RR is >8/min, ventilation is probably adequateQuick FVC: How high can they count with one

breath (counting to 20 is roughly equal to 2 L)ABG is the only certain method of determining

adequate ventilation

Evaluating the Patient5. What do the eyes look like?

The eyes are your biggest friend in an emergency When examining pupils, make sure the lights are

off and the room is as dark as possible Use a bright light If there are abnormalities, ask to look at a drivers

license or other photo or ask family members (is it old or new?)

Evaluating the Patient: The Eyes

1. Observe for blinking at rest, to light, to threat, or loud sound

2. Observe the position of the eyelids Lift and release the lids, noting the tone In unconscious pts the eyelids close gradually after they

are released, a mvt that can not be duplicated voluntarily by a hysterical patient

3. Observe the position of the eyes A light held 50 cm from the face should reflect from the

same point on each pupil if the eyes lie on conjugate axes

4. Test for corneal reflex (if the patient is not easily arousable) Should cause bilateral response of eyelid closure and

upward deviation of the eye (Bell’s phenomenon)

Evaluating the Patient6. Observe the size of the pupils and

reactivity to lightThe presence or absence of the light reflex is

the single most important physical sign potentially distinguishing structural from metabolic coma

Pupillary pathways are relatively resistant to metabolic insult; midbrain lesion destroy it

Both anatomic innervations (sym and parasymp) are tonically active, and the resting pupil represents a balanceUnopposed parasymp pupil: 1.5-2 mmUnopposed symp pupil: 8-9 mm

Coma: pupil size and reactivity

Smaller, reactive pupils persist in metabolic coma

Larger, unreactive pupil(s) reflect third cranial nerve or midbrain lesion

Pinpoint, reactive pupils from pontine lesion (or narcotic overdose)

Medicinal eyedrops may impair light reflex

Evaluating the Patient7. Examine for the Oculocephalic reflex (“Doll’s

Head Eye Phenomenon”) Hold the eyelids open and briskly rotate the head

from one side to the other, at least briefly holding the endpointsPositive response: contraversive conjugate eye

deviation (head to the right, eyes to the left) Briskly flexed and then extended

Positive response: deviation of the eyes opposite; the eyelids may open reflexly (dolls head phenomenon)

Evaluating the Patient8. Cold calorics (oculovestibular reflex)

Can be very helpful in evaluating for brain death Not useful in an acute setting as it is time

consuming and somewhat cumbersome

Evaluating the Patient 9. Examine the motor

function What is the tone

(normal, flaccid rigid) What is the strength (if

the patient can cooperate) or response to pain Apply nailbed

pressure or other noxious stimuli

Normal response: pushing the stimulus away, quick and non-stereotyped withdrawal of the limb, or mvt of the body and limb away from the stimulus

Evaluating the Patient10. Check the Reflexes

Have a reflex hammer (even skilled examiners cannot elicit reflexes with a stethescope)

Reflexes should be symmetric Upgoing toes/pathologic reflexes always indicate

some CNS dysfunction

Case 5What test do you want to order for this patient?

Subarachnoid hemorrhage

Berry aneurysm Berry aneurysm commonest if no commonest if no traumatrauma

Verify blood by CT, Verify blood by CT, or LP if CT normalor LP if CT normal

Emergent angio and Emergent angio and surgical or surgical or interventional interventional managementmanagement

Intubate if GCS <8 or hypoxemia

IV Fluids (2L 0.9% NS)

MAP ≤120 mm Hg and systolic <180 mg Hg

Nimodipine 60 mg 6xs/daily

Phenytoin (if seizures occur)

EVD for acute hydrocephalus