Neuro part 2 Flashcards
Pathophys of Bell palsy
Edema and ischemia of the facial canal that causes compression of the facial nerve
Etiology of Bell palsy
HSV and other infections
FHx
Viral and/or autoimmune reactions that cause the facial nerve to demyelinate
General sx of Bell palsy
Acute onset of unilateral upper and lower facial paralysis over a 48-hr period Posterior auricular pain Decreased tearing Hyperacusis Taste disturbances Otalgia
Early sx of Bell palsy
Weakness of the facial muscles Poor eyelid closure Aching of the ear or mastoid Alteration of taste Hyperacusis tingling or numbness of the cheek/mouth Epiphora- excessive watering of the eye Ocular pain Blurred vision
Workup of Bell palsy
Nerve conduction test
EMG
Tx of Bell palsy
Corticosteroids- prednisone
Acyclovir if you suspect HSV
Eye care with topical ocular lubrication
Botulinum can be used to protect the cornea
Pathophys of encephalitis
In general, the virus replicates outside the CNS and gains entry to the CNS wither by hematogenous spread or by travel along neural pathways
Once across the blood-brain barrier, the virus enters neural cells, with resultant disruption in cell functioning, perivascular congestion, hemorrhage and a diffuse inflammatory response.
Etiology of encephalitis
Usually infectious in nature
Most of the viral agents are transmitted through person-to-person contact
West Nile virus can be transmitted through organ transplantation and blood transfusion
Mosquitos and ticks can spread the viruses
Hx of encephalitis
Viral prodrome is several days: Fever HA N/V Lethargy Myalgias With many viruses, rash, LAD, hepatosplenomegaly, and parotid enlargement Then, encephalopathy Behavioral and personality changes with decreased level of consciousness Neck pain, stiffness Photophobia Lethargy Generalized or focal seizures Acute confusion or amnestic states Flaccid paralysis
PE of encephalitis
AMS Personality changes Focal findings, such as hemiparesis, focal seizures, and autonomic dysfunction Movement disorders Ataxia Cranial nerve defects Dysphagia Meningismus Unilateral sensorimotor dysfunction
Workup of encephalitis
CBC with diff
CMP
Glucose
LP
Urine electrolyte if SIADH suspected
Urine or serum tox
HSV cultures and Tzanck smear if suspect HSV
Complement fixation antibodies for arbovirus
Heterophile antibody and cold agglutinin for EBV
Head CT with and without contrast
CSF analysis
Most important in ED to r/o bacterial meningitis is prompt Gram stain, and if available, PCR of the CSF with HSV suspected
Tx of encephalitis
Except for HSE, and varicella-zoster, viral encephalitis can only be treated with supportive care
Acyclovir for HSE and varicella-zoster
With hydrocephalus and increased ICP, manage fever and pain, control straining and coughing, prevent seizures and systemic hypotension
Elevate head, monitor neurologic status
Mannitol for severe cases, dexamethasone
Pathophys of epidural hematoma
Usually results from a brief linear contact force to the calvaria that causes separation of the periosteal dura from bone and disruption of interposed vessels d/t shearing stress
Hx of epidural hematoma
Suspect in any individual who sustains head trauma
Classically associated with a lucid interval between initial LOC at the time of impact and a delayed decline in mental status
HA
N/V
Seizures
Focal neurologic deficits
PE of epidural hematoma
Bradycardia and/or HTN indicative of elevated ICP Skull fxs, hematomas, or lacerations CSF otorrhea or rhinorrhea Hemotympanum Instability of the vertebral column Alteration in level of consciousness Anisocoria Facial nerve injury Weakness Other focal neurological deficits
Etiology of epidural hematoma
Trauma Anticoagulation Thrombolysis LP Epidural anesthesia Coagulopathy or bleeding diathesis Hepatic dz with portal HTN CA Vascular malformation Disk herniation Paget dz of bone Valsalva maneuver HTN Chiropractic manipulation Acupuncture
Workup of epidural hematoma
CBC with platelets PTT/aPTT CMP Tox screen and serum EtOH Type and cross CT head without contrast
Tx of epidural hematoma
Stabilize ABCs Immobilize spine Thorough trauma eval Small hematoma- treat conservatively with close observation Neuro consult Treat elevated ICP Treat persistent bleeding with vit K, protamine sulfate, FFP, platelet transfusions, or clotting factor concentrates Surgery is definitive
Pathophys of subdural hematoma
Usual mechanism is a high-speed impact to the skull
This causes brain tissue to accelerate or decelerate relative to the fixed dural structures, tearing blood vessels
Etiology of acute subdural hematoma
Head trauma Coagulopathy or medical anticoagulation Nontraumatic intracranial hemorrhage d/t cerebral aneurysm, AV malformation, or tumor Postsurgical Intracranial hypertension Child abuse or shaken baby syndrome Spontaneous or unknown
