Neurological Emergencies Flashcards
What are the types of ischemic strokes?
1- embolic: cardioembolic or atheroembolic from carotids
2- atherosclerotic:lacunar small vessel or intracranial large artery
How does an ischemic stroke present?
Sudden onset of localizing neurological deficits
do a CT scan immediately to exclude hemorrhagic strokes then give alteplase
What are the contraindications for thrombolytics?
1- major head trauma or surgery within the last 3 weeks
2- prior hemorrhagic stroke
3- ischemic stroke within prior 6 months
4- CNS neoplasm
5- GI bleeding within 1 month
6- active bleeding
How are ischemic strokes treated?
- if > 18 years old & <4.5h -> give thrombolytics (alteplase works best for small & medium vessel occlusions)
- if NIHHS > 6 or there are contraindications -> CT angiogram (look for large vessel occlusion)
What is the cause of a hemorrhagic stroke?
rupture of deep penetrating vessels -> rapidly expanding hematoma -> mass effect & tearing off ascending & descending tracts
commonly caused by
- HYPERTENSION
- amyloid angiopathy (in elderly)
- use of anticoagulants (warfarin, enoxaparin, apixaban)
What are the common locations of intracranial hemorrhages?
HYPERTENSIVE ICH
- basal ganglia
- thalamus
- brainstem
- cerebellum
AMYLOID ICH (lobar)
- frontal
- parietal
- occipital
What is the presentation of a hemorrhagic stroke?
- headache
- focal neurological symptoms
- depressed level of consciousness
- coma
DETERIORATES VERY QUICKLY
How is a hemorrhagic stroke managed?
1- ABC -> intubation for airway protection
2- treat hypertension
3- reverse anticoagulation -> FFP or PCC
4- rehab
What is the cause of thunderclap headaches?
subarachnoid hemorrhage -> rupture of intracranial aneurysm results in spillage of blood contents into subarachnoid space
- Estrella de la muertes -> headahce emergency
What are the complications of subarachnoid hemorrhages?
- death
- coma
- rebleeding -> 80% mortality
- SIADH or cerebral salt wasting
- Neuromyocardiac stunning -> Takasubo’s cardiomyopathy
- neurogenic pulmonary edema
How is a subarachnoid hemorrhage treated?
1- ABC 2- control blood pressure <120SBP 3- surgical clipping or angiographic coiling or the aneurysm 4- prevent vasospasm 5- treat SIADH or CSW 6- supportive care
How does myasthenia gravis manifest?
generalized muscle weakness that could lead to respiratory failure
- any skeletal muscle could be affected
- antibody production against acetylcholine receptors, MuSK or LPR4
- could be thymoma or non-thymoma related
What is the presentation of myasthenia gravis?
fluctuating muscle weakness that varies in severity precipitated by infections, surgery, immunization, heat, emotional stress, pregnancy, worsening or chronic illnesses
- worsens with physical activity & improves with rest
- extra ocular muscles -> diplopia & ptosis
- bulbar muscle weakness -> difficulty chewing or frequent choking, dysphagia, hoarseness, & dysarthria
- facial muscles -> expressionless face
- neck muscles -> dropped-head syndrome
- limbs -> weakness of the proximal muscles more than distal & upper limb more than lower
- intercostal muscles & diaphragm -> myasthenic crises
How can myasthenia gravis be diagnosed clinically?
patient will fail sustained muscle contraction
- patient will not be able to abduct their arms > 120s
- sustained upward gaze >60s results in ptosis
- sustained lateral gaze results in diplopia
What workups should be ordered to confirm the diagnosis of myasthenia gravis?
- serology -> anti-acetylcholine receptor antibodies, anti-MuSK, & anti-LPR4
- neurophysiological testing -> DECREMENTAL RESPONSE with repetitive nerve stimulation
- imaging -> to rule out thymoma
How is myasthenia gravis treated?
- For acute relapses -> IVIG or plasmapheresis
- For maintenance -> steroids & immunosuppressants
Why are steroids contraindicated in acute relapses of myasthenia gravis?
could increase myopathy leading to myasthenic crises
What is the presentation of a myasthenic crises?
1- progressive generalized weakness & fatigue
2- short sentences, shortness of breath, or respiratory arrest
3- decrease in vital capacity to <1L & negative inspiratory force (NIF) <20
- may have other symptoms of MG -> ptosis, dysphagia, dysphonia, & neck weakness
What is the management of a myasthenic crises?
1- ABC -> intubation or BIPAP
2- monitored in ICU & hourly NIF & VC
3- plasmapheresis or IVIG to abort crisis
4- maintenance with immunosuppressants
What is the definition of status epilepticus?
prolonged generalized seizures > 5 mins OR any back-to-back seizures with no regaining of consciousness in between
- diminished mental status, airway compromise, hypoxia or aspiration -> life-threatening
How is status epilepticus managed?
1- ABCDEFG (dont ever forget the Glucose)
2- First-line agents (0-5 mins) -> BENZOS (lorazepam or midazolam)
3- Second-line agents (10-15 mins) -> Levetiracetam OR phenytoin OR valproate
4- if refractory (15-20 mins) -> general anesthesia (propofol or ketamine)
What are the causes of spinal cord compression?
- TRAUMA is the most common
- tumors
- epidural abscess
- epidural hematoma
- herniated disc
- spinal stenosis
What is the clinical picture of spinal cord compression?
- symmetric flaccid paralysis below the level of the lesion with sensory loss & bladder dysfunction
- depending on the location of the compression it may present with -> central cord syndrome, Brown-Sequard syndrome, or Cauda Equina syndrome
Compression of the L2-S1 nerve root will result in?
Cauda Equina Syndrome
- sciatica
- asymmetric weakness of LMNL
- areflexia
- sexual & sphincter dysfunction
- saddle anesthesia
What is the most common cause of Cauda Equina syndrome?
metastases
How is cord compression treated?
- epidural abscess & osteomyelitis -> antibiotics
- metastatic tumors -> high dose steroids & radiation
- surgical decompression, drainage, realignment, & fixation
What is the pathophysiology of Guillian-Barre Syndrome?
- post-infectious immune-mediated neuropathy
- autoimmune destruction of nerves in the PNS
- most common cause of acute, flaccid, neuromuscular paralysis
- can be demyelination (80% recovery) or axonal (rare recovery)
What is the clinical presentation of GBS?
- symmetric ascending paralysis, numbness, & tingling
- 7 - 10 days after infections (C. jejuni)
- if respiratory muscles are involved -> respiratory failure & death
- cranial nerve involvement -> facial weakness, dysphagia, & dysphonia
- autonomic involvement -> hypotension/hyertension & bradycardia/tachycardia (FATAL)
- areflexia is the most important sign in the physical exam
What are the methods of investigation used to confirm the diagnosis of GBS?
- nerve conduction studies -> conduction block & slow conduction velocities
- LP -> typical albuminocytological dissociation
- NIF to assess respiratory muscle function
How is GBS treated?
IVIG or plasmapheresis
What are the causes of meningitis?
1- Bacterial - Strep. pneumonia - N. meningitidis - H. influenzae - L. monocytogenes (in >65 & <1 years of age & immunosuppressed) 2- Viral -> herpes simplex 3- TB 4- Fungal
What is the clinical presentation of meningitis?
- fever, headache, & altered mental state physically - fever - skin rash (Neisseria & Herpes) - neck stiffness - Kernig sign - Brudzinski sign
What are the diagnostics used to confirm diagnosis of meningitis?
- CBC
- electrolytes -> hyponatremia due to SIADH
- coagulation profile -> to rule out DIC
- blood culture
- LP for CSF
How can we differentiate between the causes of meningitis with CSF?
Bacterial
- neutrophils are predominant
- very low glucose
Viral
- lymphocytes are predominant
- normal glucose
Fungal
- lymphocytes are predominant
- low glucose
Tubercular
- lymphocytes are predominant
- low glucose
How is meningitis treated?
empirical therapy
- ceftriaxone & vancomycin
- ADD ampicillin in extremes of age
- give steroids incase of Strep. pneumonia -> to prevent deafness
What are the causes of encephalitis?
- herpes virus
- enterovirus
What is the clinical picture of encephalitis?
- fever
- headache
- altered mental status
- seizures
- focal features
What are the diagnostic tools used to confirm diagnosis of encephalopathy?
- MRI
- EEG
- CSF
- PCR
What is the cause of bitemporal encephalitis?
herpes
How is encephalitis treated?
only treatment available is for HSV
- Acyclovir until PCR is negative
- supportive care
What are the complications of encephalitis?
- cognitive impairment
- seizure disorders (epilepsy)
What are the causes of brain abscesses?
- infections -> otitis media, mastoiditis
- hematogenous seeding -> septic embolus or endocarditis
- trauma
- surgery -> craniotomy
can invade brain by direct spread or through hematogenous seeding (caused by multiple multiorganisms)
What are the clinical features of a brain abscess?
- headache & fever
- focal neurological deficits
- increased intracranial pressure
- seizure
What diagnostic methods should be used to confirm diagnosis of a brain abscess?
- MRI WITH CONTRAST
- Lumbar puncture
culture - histopathology
How are brain abscesses treated?
- broadspectrum antibiotics
- add toxoplasmosis coverage in HIV patients
- neurosurgical drainage & send pus for culture
- maintain intracranial pressure
