Central and Peripheral Nervous System Flashcards
Vertebrobasilar System TIA
Decreased perfusion of posterior fossa
Dizziness, double vision, vertigo, numbness of ipsilateral face and contralateral limbs, dysarthia, hoarseness, dysphagia, projectile vomiting, headaches, and drop attacks
Evaluation of embolic stroke
- ECHO
- Carotid dopplers
- ECG, Holter Monitors
Subclavian steal syndrome
Stenosis of subclavian artery proximal to vertebral artery-exercise of left arm causes reversal of blood supply leading ot decreased cerebral blood flow
Vertebrobasilar arterial insufficiency
BP in left arm is less than right arm, decrease pulse in left arm
Upper extremity claudication
Treatment: surgical bypass
Ischemic Stroke Diagnosis, Treatment and Prevention
Diagnosis: CT scan: initial (ischemic=hypodense, hemorrhagic=hyperdense)
ECG, CXR-acute MI or a. fib could be cause
Carotid duplex scan-degree of stenosis
ECHO
MRA-is definitive test
Treatment:
Hyperventilation or mannitol if cerebral edema present
Acute: airway protection, O2, IV fluids
T-PA within 3 hours unless uncontrolled HTN, bleeding disorder or is anticoagulated, or history of recent trauma, or surgery-do not give aspirin for first 24 hrs,, keep BP less than 185/110
Aspirin if more than 3 hours (clopidogrel if cannot take aspirin)
Keep NPO and elevate head
Do not give antihypertensives unless:
- Patient is >220/120 or MAP is >130
- Patient has acute MI, aortic dissection, severe HF, Hypertensive encephalopathy
- Receiving thrombolytic therapy
Prevention:
Control of : HTN, DM, smoking, hypercholesterolemia, obesity
Aspirin
Surgery-carotid endarterectomy
Symptomatic >50% stenosis
Asymptomatic >60% stenosis
Pinpoint pupils vs. poorly reactive pupils vs. dilated pupils for location of hemorrhagic stroke
Pinpoint=pons
Poorly reactive=thalamus
dilated=putamen
Treatment and diagnosis of intrancerebral hemorrhage
Diagnosis: Ct scan (hyperdense regions)
Treatment: admit to ICU
ABCs
BP reduction if systolic >160 and diastolic >105 use nitroprusside
Mannitol and diuretics if increased ICP
Surgical evacuation of cerebellar hematomas if present
Diagnosis and treatment of subarachnoid hemorrhage
Diagnosis: Noncontrast CT scan
Perform LP if CT is unrevealing or negative. LP is diagnostic (do not perform if papilledema is present)-xanthochromia is gold standard
Once diagnosed perform cerebral angiogram
Rerupture-24 hrs
Vasospasm-3 days
Treatment:
Surgical clip-coiling or stenting
Medical: bed rest in dark room stool softeners acetaminophen for analgesia IV fluids for hydration Control HTN-lower BP gradually CCB-nefedipine or nomodipine for vasospasm
Diffuse axonal injury
Most significant cause of morbidity in patients with tramautic brain injuries
Due to traumatic deceleration-vegetative state
Occurs in gray-white matter junction-minute punctuate hemorrhage s with blurring of gray-white interface
Diagnosis: MRI most sensitive
Treatment of Parkinsons
Carbidopa-levidopa:most effective
Bromocriptine, pramipexole: (dopamine receptor agonists)use early on
Seelgiline: (MAO-B inhibitor)
Trihexyphenidyl and benztropine: helps with tremor, do not use in older or demented patients
Amitryptyline: depressed as well
Deep brain stimulation if patient does not respond to medications or severe disease before 40
Diagnosis and treatment of Huntingtons Chorea
Diagnosis: MRI shows atrophy of head of caudate nuclei
DNA testing confirms
Treatment:
no cure
Dopamine blockers help with psychosis and improve chorea. Anxiolytic and antidepressants may be necessary
Physiologic tremor
Caused by fear, anxiety, fatigue
Hypoglycemia, hyperthyroidism, pheochromocytoma
Alcohol withdrawal, valproic acid, lithium, methylxanthines, caffeine, and thephylline
Treat the underlying cause
Essential tremor
AD
Induced or exacerbated by intentional activity
Decreased by alcohol use
treat with propanolol
Cerbellar tremor
happens with action
Associated with ataxia, nystagmus and dysarthia
Improved by rest
Treatment of Tourette’s syndrome
Clonidine
Pimozide
Haloperidol
Diagnosis and treatment of Alzheimer’s
Diagnosis: clinical but can see diffuse cortical atrophy on CT or MRI
Treatment:
Cholinesterase inhibitors: donepezil, rivastigmine and glanatamine
Dietary supplement of ginkgo, lecithin
Vitamin E at megadoses
Diagnosis and treatment of Delirium
Mental status exam >25 (?)
labs: chemistry panel, vitamin B12, thiamine
LP
Treatment: underlying cause
Haloperidol
Criteria for brain death
Irreversible absence of brain or brainstem function-unresponsiveness, apnea despite adquate oxygenation and ventilation, no brainstem reflexes (pupils, calorics, gag, cornea, doll’s eyes)
Core body temp>89.6 ( cannot be diagnosed in hypothermia)
Imaging study that provides explanation
EEG shows electrical silence
Carotid TIA
Temporay loss of speech, paralysis or parasthesias of controlateral extremity, clumsiness of one limb
Amaurosis fugax transient curtain like loss of sight in ipsilateral eye due to microemboli in eye
Diagnosis and treatment of MS
Diagnosis: clinical
MRI: test of choice-white matter lesions
LP: oligoclonal bands of immunoglobulin G
Evoked potentials: newly remyelinated nerves will conduct sensory impulses more slowly
Treatment:
Acute exacerbations: High dose IV corticosteroids shorten acute attack
Therapeutic plasma exchange for steroid refractory
Resolve within 6 weeks on their own
Disease modifying:
Interferon B, glatiramer acetate
Symptomatic
Baclofen and dantrolene for muscle spasticity
carbamazepine or gabapentin for neuropathic pain
Treat depression if indicated
Guillain-Barré syndrome diagnosis and treatment
Diagnosis:
CSF analysis-elevated protein, but normal cell count (WBC and RBC) normal glucose
Electrodiagnostic studies: decreased motor nerve conduction velocity
Treatment:
monitor pulmonary function-mechanical ventilation may be necessary
Adminster IV immunoglobulin if significant weakness, plasmapharesis may reduce severity of disease
Myasthenia gravis diagnosis and treatment
Diagnosis:
Acetylcholin receptor Ab test of choice
EMG shows decreased response to repetitive stimuli
CT of thorax to rule out thymoma
Edrophonium (tensilon) test: AChE cause improvement of symptoms but high false positive rate
Treatment:
AChE inhibitors: pyridostigmine (sympotmatic)
Thymectomy: symptomatic or complete remission
Corticosteroids: no response to AChE inhibitors
Azothioprine and cyclosporine are alternatives
Plasmapharesis: if all else fails or respiratory failure
IV immunoglobins for acute exacerbations
Monitor FVC: 15 ml/kg (1L) indication for intubation
Avoid: aminoglycosides, tetracyclines, B-Blockers, Antiarrhythmis, quinidine, procainamide and lidocaine
Diagnosis and treatment of Duchennes
Diagnosis: serum creatinine phosphokinase markedly elevated
DNA testing
Treatment:
Prednisone increases strength in muscle function, pulmonary function and may reduce risk of scoliosis
surgery to correct progressive scoliosis
Neurofibromatosis Type I
AD: cafe au lait spots, neurofibromas, CNS tumors (gliomas, meningiomas), axillary or inguinal freckling, iris hamartomas (Lisch nodules), bony lesions
Complications: scoliosis,, pheo, optic nerve gliomas, renal arterty stenosis
Seizures, mental retardation, short height, marcocephalic
surgically excise symptomatic neurofibromas
Neurofibromatosis Type II
AD
bilateral acoustic neuromas (MRI)
multiple meningiomas, cafe au lait spots, neurofibromas, and cataracts
Tuberous sclerosis
AD
Cognitive impairment, epilepsy, and skin lesions (facial angiofibromas, adenoma sebaceum)
Retinal hamartomas, renal renal angiomyolipomas, and rhabdomyomas
Sturge Weber Syndrome
Capillary angiomatoses in pia matter
Facial vascular nevi(port wine stain)
Epilepsy and mental retardation are present
Treat epilepsy
VHL
AD
Carvernous hemangiomas of brain or brainstem, renal angiomas and cysts in multiple organs
Associated with renal cell carcinoma
Associated with pheochromocytomas
Dizziness workup
Audiogram if vestibular symptoms present
CT scan/MRA if TIA suspected
MRI of posterior fossa if structural lesion suspected
Central vs peripheral vertigo
Central: gradual onset
Other brainstem findings present: weakness, hemiplegia, diplopia, dysphagia, dysarthria, facial numbness-look for cardiovascular risk factors
Nystagmus can be biderictional or vertical
patient responds to every tilt test
Peripheral: cochlear or retrocochlear
Abrupt onset
Nausea and vomiting, head position has strong effect on symptoms, no other brainstem deficits except tinnitus/hearing loss
Tilt test can only be performed once because patient will be refractory
NO peripheral nystagmus
Use MRI to rule out ischemic event
Benign positional vertigo
Semicircular canal dysfunction
Vertigo is experienced only in specific positions or change in position
Lasts for a few moments
Treat with Meclinzine
Ménière’s disease
Triad of vertigo, tinnuitis and hearing loss
Nystagmus in acute attack
Attacks lasts for hours to days and recur several months or years later
Hearing loss becomes permanent
Treat with sodium restriction and diuretics, anticholinergics or antihistamines
Diagnosis and treatment of vasovagal syncope
preminitory symptoms: pallor, diaphoresis, lightheadedness, nausea, dimming of vision, roaring in the ears
Tilt table study can reproduce symptoms
Treatment: Assuming supine posture and elevating the legs
B blockers and disopyramide
Orthostatic hypotension diagnosis and treatment
Positive tilt table test
Premonitory symptoms: lightheadedness, nausea…
treat with sodium intake and fluids
Consider fludrocortisone
Treatment of Complex partial seizures
Consciousness impaired, postictal confusion
Automatisms: involuntary repetitive movements-lip smacking or chewing
Olfactory or gustatory hallucinations
Phenytoin and carbamazepine
Treatment of simple partial seizures
consciousness remains intact
Phenytoin and carbamazepine
Treatmetn of tonic clonic seizures
- Sudden loss of consciousness
- rigidity
- musculature jerking
- Postictal confusion and drowsiness
- tongue biting, vomiting, apnea and incontinence
Phenytoin and carbamazepine
Absence seizure treatment
Valproic acid or ethosuximide
Treatment of status epilepticus
establishing airway
Give: IV diazepam, IV phenytoin, and 50 mg dextrose
Treat resistant cases with IV phenoarbital
Workup of seizure
Diagnosis:
Check anticonvulsant levels
CBC, calcium, sodium, glucose, BUN, LFTs, urinalysis
EEG-normal EEG in first seizure is lower risk of recurrence
CT scan
MRI with and without gadolinium
LP and blood cultures if febrile
Treatment of seizure
History of seizures:
Loading dose of anticonvulsant (add second if not controlled) continue for 2 years then slowly taper down and confirm with lack of seizure on EEG
First seizure EEG and neurology consult-first steps Normal EEG-do not treat Antiepileptic drugs started if EEG is abnormal, brain MRI is abnormal patient is status epiepticus Pregnancy test before prescribing
