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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
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Neurologic Emergencies Neurology Clerkship NinithKartha, 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 • 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 1 • Can you localize the lesion?
Localization Central nervous system Peripheral nervous system Nerve root Plexus Peripheral nerve Neuromuscular junction Muscle • Brain • Spinal cord The most important step in neurologic localization is differentiating a central nervous system lesion from a peripheral nervous system lesion
Localization Upper motor neuron Lower motor neuron Severely reduced bulk with fasciculations Reduced tone Severe weakness Hypotonia • Mildly reduced bulk • Increased tone • Mild/moderate weakness • Hyper-reflexia & pathologic responses Grading muscle power 5: Full strength 4: Movement against some resistance 3: Movement against gravity only 2: Movement with gravity eliminated 1: Flicker or trace contraction 0: No contraction Grading reflexes 4: Hyper with pathologic responses 3: Hyperactive 2: Normal 1: Diminished 0: Absent
Localization • Spinal levels C5/6 Its easy to remember…1/2, 3/4, 5/6, 7/8 C7/8 ALWAYS ABNORMAL: Asymmetric reflexes Pathologic responses (Babinski, clonus = CNS) Absent reflexes (PNS) L3/4 S1/2
Case 1 • 1. What studies do you want to order and why?
Spinal Cord Compression Management Differential • Dexamethasone (100 mg IV followed by 16 mg PO daily in divided doses) • Surgical evaluation • Radiotherapy 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 2 • Can you localize the lesion?
Localization Central nervous system Peripheral nervous system Nerve root Plexus Peripheral nerve Neuromuscular junction Muscle • Brain • Spinal cord The most important step in neurologic localization is differentiating a central nervous system lesion from a peripheral nervous system lesion
Localization REFLEX ARC
Case 2 • 1. What studies do you want to order and why? • What else do you need to get the above done?
Test Results CSF Analysis EMG/NCV • WBC 2 • RBC 0 • Protein 103 (15-45) • Glucose 50 • Coags and platelets WNL Conduction block
Guillain-Barre Syndrome Clinical Features Areflexia Bowel & bladder are usually spared Autonomic dysfunction Symptoms should not proceed >8 weeks 98% of pts achieve “plateau phase” by 4 weeks Duration of “plateau” 12 days • Typically follows an infectious process (2/3rds of pts) • C. jejuni, CMV, EBV, M. pneumoniae • Presents with numbness & tingling in the feet that ascends • Pain the back & limbs is common • Weakness follows sensory disturbances
Guillain-Barré syndrome • Ancillary studies • Albuminocytological dissociation with elevated CSF protein with no or a few mononuclear cells • May be normal in the first week • If WBC count >10 think about Lyme, HIV, sarcoidosis • Antiganglioside antibodies • GM1 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 slowing
Guillain-Barré syndrome: Subtypes 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 • 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
Treatment • IVIG (0.4g/kg/day for 5 days) is at least effective as plasma exchange without some side effects • Should 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 mmHg • Oropharyngeal weakness
Case 1 • A 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 3 • Can 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.
Questions • What 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
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 and 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 185/110 • IV tPA must be/may be given within 4.5 hrs of stroke onset • Neuro deficit (NIHSS score 5 to 22) must not be rapidly improving (TIA) or post-ictal • Normal PTT, PT<15 sec, platelets >100,000 • No bleeding, recent surgery, MI, arterial puncture or LP • No blood, or edema/infarct > 1/3 of MCA territory on CT TIME IS BRAIN!!!
Clinical History • What imaging test do you want to order? • CT scan • in deteriorating patient, quickly rules out hemorrhage, mass (tumor, abscess) or early infarct edema • shows cortical infarcts by 1-2 days, may miss lacunar infarcts • MRI scan • highest resolution scan, but longer scanning time • DWI (diffusion weighted imaging) detects impaired movement of water in infarct immediately • non-invasively view arterial supply (MRA) • contraindications: pacemaker
Non Infused Head CT • What 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
Evaluation • Based on the patient’s history, physical exam findings, and CT scan, she was taken to Interventional Radiology for a cerebral angiogram…
Angiogram MCA occlusion
Clinical History • The 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…
Questions • What 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 tPA Post tPA
Question • By 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?)
Question • Answer…. • 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 4 • Can you localize the lesion
Peripheral NS • The PNS generally includes • The nerve cell bodies • The peripheral nerves • Roots • Plexus • Nerve • The neuromuscular junctions (NMJs) • The muscles
Localization NMJ • Fluctuating weakness (pre- and post-synaptic) • Normal bulk and tone • Normal sensory exam • Normal reflexes (usually)
Case 2 • How 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 Test • Tensilon Test • Respiratory Studies!!! • BMP w/ Mg/Phos, PT/PTT, ionized calcium • May need Quinton catheter placed by IR
Case 2 • Studies • EMG/NCS with repetitive stimulation or single fiber EMG • Chest CT • Those 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 5 • A 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 5 • Can you localize the lesion?