Neuro Flashcards
Different gait abnormalities that are associated with various neurologic disorders
Magnetic Gait - normal pressure hydrocephalus
–Wide based, unsteady
–Feet stuck to the floor like magnets
Parkinsonian Gait
–Shuffle, no arm swing, slouched over
–Multiple steps to turn around
Symptoms of ischemic stroke and things you would be worried about
Symptoms start suddenly over the course of minutes
–Negative symptoms - take things away
–Unipolar
Facial droop, unipolar arm weakness, speech problems
Symptoms happen on the opposite side of the body from the stroke area
Left sided - Right hemiparesis, speech problems
Right sided - Left hemiparesis, visual/spatial problems
Things you would be worried about are last time known well to determine if tPA is indicated.
What is a hemorrhagic conversion
Blood flow is restored to a part of the brain that had been necrotic and when blood returns to this necrotic area, it immediately bleeds
What are the two types of stroke and how do we tell the difference?
Ischemic and hemorrhagic
Most common is ischemic caused by emboli
Able to tell difference with a non-contrast head CT stat to look for bleed
What is the Cincinnati Prehospital Stroke Scale
Facial droop
Arm drift
Speech difficulty
If 1/3 finds are abnormal, 72% probability of ischemic stroke. If all 3 are abnormal, 85% probability of ischemic stroke
How soon do we want to give tPA (window from last known well and window from arrival to the ED)
Want to give tPA within 3 hours of symptom onset and 1 hour of arrival to the ED
Can give up 4.5 hours if meets all criteria
Who might be appropriate for tPA
Inclusion criteria:
–Age 18 years or older
–Clinical diagnosis of ischemic stroke with a measurable neurological deficit
–Time of onset less than 3 hours
Exclusion criteria:
–Evidence of intracranial hemorrhage on non-contrast CT
–Clinical suspicion of subarachnoid hemorrhage even with normal CT
–CT shows multilobar infarct
–Hx of intracranial hemorrhage/stroke
–Uncontrolled HTN
–Current use of ACs
–Age >80
What systolic blood pressure should be goal s/p stroke
SBP> 140
Can give IV labetalol for treatment of HTN
Anticoagulation s/p stroke
Generally not indicated d/t the risk of hemorrhagic bleed.
ASA is the mainstay
Presentation of TIA
Sudden dimming or loss of vision (amaurosis fugax) unilaterally - ipsilateral
Half vision
Paresthesia of the contralateral arm, leg or face
Transient Aphasia
Slurred speech
Mental confusion
TIA is often an important warning sign that stroke may occur soon
Lasts less than 1 hour with no residual deficits
Two types of intracranial hemorrhage
Intra-axial hemorrhage (within the brain)
–Caused by rupture of aneurysms
–Difficult to treat because need to pass through brain tissue in order to get there
Extra-axial hemorrhage (just outside brain tissue)
–Epidural hemorrhage - between dura mater and skull - caused by trauma
—-Presents as LOC then lucid then deterioration then vomiting then LOC again
–Subdural hemorrhage - tearing of the bridging veins in the subdural space between dura mater and arachnoid mater
—-Can start slowly and progress over several days
–Subarachnoid hemorrhage - can result from trauma, rupture of aneurysms or ateriovenous malformations.
—-Worst headache of my life - sudden onset
Imaging and SAH
Non contrast Head CT can show SAH as long as sxs started within the last 6 hours.
A lumbar puncture will need to be done if negative NCHCT to assess for blood in CSF
Lumbar Puncture tubes
1: cell count and diff
#2: Chemistry (protein and glucose)
#3: Microbiology studies
#4: Cell count and diff again
Presentation and treatment of Brain Herniation
Presents as coma, abnormal posturing, vomiting, unequal pupils
Cushings Triad of Increased ICP:
-Increased SBP
-Decreased HR
-Slowing, irregular RR
Treatment: Hydralazine to lower the BP but not the HR
Intracranial hemorrhage treatment
Due to serious threat of respiratory failure, early intubation is often needed
Raise the head of the bed to >30 degrees
Medications:
–AntiHTN treatment to bring MAP <110
–Mannitol and hypertonic saline can reduce swelling of the brain
–Fosphenytoin is given in case of seizures
Surgery:
–If hematoma is greater than 3cm then surgery is required.
–External Ventricular drain (EVD) to drain excess CSF or blood to allow for swelling
Definition of brain death
Cerebral death - brain stem is still alive so HR and RR continue without aid but rest of brain is dead
Whole brain death is the death of cerebrum and brain stem - needs life support
–No response to pain
–Absent cranial nerve reflexes
–EEG shows no brainwave activity at all
The provider has an ethical responsibility, absent one’s own personal beliefs, to discontinue life support to a dead person
How to manage status epilepticus
Defined as seizure lasting longer than 30 mins
Given risk for threatened airway, should be intubated immediately
Medicines:
Diazepam 10mg IV over 2 minutes, may be repeated after 10 mins
Regardless of response to diazepam should give either:
–Phenytoin 18-20mg/kg IV at a rate of 50mg/min
or
–fosphenytoin 18-20 PE/kg at a rate of 150PE/min
If no response to diazepam and phenytoin:
Phenobarbital 10-20mg/kg IV at a rate of 50mg/min
Should be getting EEG
Symptoms of brain tumors
Generalized or focal disturbances of cerebral function
increased ICP
Personality changes
Intellectual decline
Emotional lability
Seizures
Headaches
Nausea
Types of brain tumors: Glioblastoma Multiforme
Presents commonly with nonspecific complaints and increased ICP
Rapidly progressive with a very poor prognosis
What is the most common primary tumor to metastasize to the brain
Lung carcinoma
Pathophysiology of Parkinson’s Disease
Caused by death of dopamine generating cells in the substantia nigra
The net effect of dopamine depletion is to produce hypokinesia, an overall reduction in motor output
What are the 4 cardinal signs of Parkinson’s Disease
Tremor - tremor at rest that disappears with movement
Rigidity - often cogwheeling rigidity
Bradykinesia and akinesia
Postural instability
Treatment for Parkinson’s Disease
Levodopa - increases dopamine. Combined with carbidopa to help reduce side effects of levodopa - Sinemet
Dopamine agonists
-Pramipexole
-Ropinirole
Monoamine oxidase inhibitors (prevent the breakdown of dopamine)
-Selegiline
-Rasagiline
Amantidine
Deep Brain Stimulators
Red flags for Cauda Equina
Severe back pain
Saddle anesthesia
Bladder and bowel dysfunction
Sciatica-type pain on one side or both sides, although pain may be wholly absent
Weakness of the muscles lower legs
Achilles reflex absent
Sexual dysfunction
Absent anal reflex
Gait disturbance
Canadian C-Spine Rule
Determines if patient should receive dedicated spinal CT
Any high risk factors? (If yes, CT)
–Age >65
–Dangerous mechanism
–Parasthesias in extremities
Any low risk factor which allows safe assessment of range of motion? (If not able to range, CT)
–Simple rearend MVC
–Sitting position in the ED
–Ambulatory at any time
–Delayed onset of neck pain
–Absence of midline c-spine tenderness
Are they able to actively rotate neck 45 degrees?
–If no, CT
–If yes, no radiography
Know the different types of Peripheral Neuritis
Zoster - Shingles, reactivation of varicella zoster virus in a specific dermatomal pattern.
—Treatment is Valacyclovir 1000mg PO TID x 7 days
Bell’s Palsy - facial paralysis of CN VII (facial nerve)
—Often caused by preceding viral infection (or bacterial - Lyme).
—Often improves with no treatment but steroids can help speed the recovery
Guillain-Barre Syndrome - inflammation of the motor neurons, usually following a viral infection.
—Increasing numbness and paralysis sometimes as far as the diaphragm, causing the need to intubation
—Treatment is either plasmapheresis or steroids
Basics of myasthenia gravis: Pathophysiology, Symptoms, Diagnostics, Treatment
Muscle weakness is caused by circulating antibodies that block acetylcholine receptors at the postsynaptic neuromuscular junction, inhibiting the excitatory effects of the neurotransmitter acetylcholine.
Most often arise from a tumor of the thymus - thymoma
Symptoms include ptosis, diplopia, difficulty chewing or swallowing, respiratory difficulties, limb weakness
Symptoms are worse when the patient is tired
If sxs are severe, they can cause difficulty breathing, this is called Myasthenic Crisis
Diagnosis is made by administering anticholinesterase inhibitor, Edrophonium 10mg IV x1 and if the sxs abruptly stop, the diagnosis can be made
Treatment includes:
—Maintenance doses of pyridostigmine several times per day
—Thymectomy
—Immunosuppressive therapy
—Plasmapheresis in Myasthenic Crisis
Duchenne Muscular Dystrophy
Gene mutation of the dystrophin gene located on the short arm of the X chromosome
DMD is a progressive disease which eventually affects all voluntary muscles and involves the heart and breathing muscles at later stages
Life expectancy is approximately 25 years old.
No treatment but steroids can help delay the eventual progression to complete immobilization
Basics of Botulism
The toxin Clostridium botulinum prevents the release of ACh at the neuromuscular junction and autonomic synapses
Often occurs from ingestion of home canned foods containing the bacteria
Symptoms begin within 72 hours and involve total cranial nerve palsy that leads to difficulty breathing
Treatment is supportive care and request for the antidote
What is the workup of a TIA? What is the priority diagnostic
Priority diagnostic is CT Head in order to distinguish between ischemia, hemorrhage and tumor
MRI can better visualize ischemic infarcts however takes longer
Cerebral angiography - can be done after a CT shows an ischemic stroke.
Treatment of TIA
In the first few days:
ASA and Clopidogrel (Plavix)
After discharge:
Usually will choose one agent
Treat HTN
In a CVA, how long from last known well can we do mechanical embolectomy for all patients
Up to 6 hours from last known well
Indications for ICP monitoring
Severe head injury (GCS <8) with an abnormal Head CT
Severe head injury (GCS <8) with a normal head CT with two of the following:
-Age >40
-SBP <90
-Abnormal motor posturing
What should the MAP be after a CVA?
Should be maintained between 110-130 to prevent cerebral vasospasm
Can help increase MAP by giving more fluids
How do you measure cerebral perfusion pressure (CPP)?
CPP=MAP-ICP
Want to keep ICP <20
Good CPP is 70
What is a medication used to counter vasospasm by preventing calcium from entering smooth muscle cells and causing contraction?
Nimodipine
Classic presentation and physical exam findings of multiple sclerosis
Sxs:
-Weakness, numbness, tingling or unsteadiness
-Spastic paraparesis
-Diplopia
-Disequilibrium
-Urinary urgency or hesitancy
-Optic atrophy
-Nystagmus
What is the physiological cause of MS?
Body’s immune system attacks myelin therefore causing decrease in the speed in which nerves interact.
Diagnostics and management of MS
LP: Slightly elevated protein and IgG in CSF
MRI of the brain
Management:
No treatment to prevent progression of the disease
Recovery from acute phases is hastened by steroids
Immunosuppressive therapy
Plasmapheresis in severe cases
Interferon
Antispasmotics
What are the common bacteria that cause meningitis
Strep pneumoniae
Hemophilus influenzae
Neisseria meningitidis
What is Kernig’s Sign
Pain and spasms of the hamstrings found in meningitis
What is Brudzinski’s Sign
Legs flex at both the hips and knees in response to flexion of the head and neck to the chest found in meningitis
What labs and diagnostics are done when considering meningitis?
LP should be done immediately:
—If bacterial, CSF will be cloudy or xanthochromic (yellow in color) with:
—–elevated pressure
——elevated protein
——decreased glucose
——presence of WBC
CSF in viral will have normal glucose and normal protein
Head CT
What is the management of meningitis?
If the pt is <50 years old:
Vancomycin + Ceftriaxone
If the pt is >50 years old:
Vancomycin + Ceftriaxone + Ampicillin
What is Cushing’s Triad
Seen in traumatic brain injury patients that are decompensating:
-Widening pulse pressure
-Decreased respiratory rate
-Decreased heart rate
Complications of Spinal Cord Injury based on the following areas:
-Cervical spine vs thoracic spine injury
-C4 injury or above:
-T4-T6:
What is the treatment for T4-T6 complication
Cervical spine - tetraplegia
Thoracic spine - paraplegia
C4 injury and above: respiratory compromise
T4-T6: May lead to autonomic dysreflexia
-emergency conditions
-Caused by exaggerated autonomic response to a stimulus (bladder or bowel distention, hot or cold stimulus, restrictive clothing)
–Diaphoresis and flushing above the level of injury
–Chills and severe vasoconstriction below the level of injury
–HTN
–bradycardia
–Headache
–Nausea
Treatment is stimulus removal
What is Brown Sequard Syndrome and treatment
Caused by damage to one half of the spinal cord:
Sxs:
-Ipsilateral upper motor neuron paralysis and loss of proprioception
-Contralateral loss of pain and temperature
Order MRI and give steroids
Management of suspected cauda equina
MRI
Steroids
Surgery for decompression
What is the most common form of neurocognitive disorder?
Alzheimer’s
Clinical diagnostic criteria for Alzheimer’s
Memory impairment and one or more of the following:
-Aphasia
-Apraxia
-Agnosia - inability to recognize an object
-Inability to plan, organize, sequence and make abstract difference
Medications used to treat Alzheimer’s Disease
Cholinesterase inhibitors:
-Donepezil (all stages of AD)
-Galantamine (mild-moderate disease)
-Rivastigmine (mild-moderate disease)
NMDA antagonist:
-Memantine (Namenda) - moderate to severe disease
Combinations:
-Memantine and donepezil - moderate to severe disease
