Neuro review part 2 Flashcards
Traumatic Brain Injury (TBI)
a blunt or penetrating insult to the brain; can be diffuse or focal
severe: GCS 3-8
moderate: GCS 9-12
mild: GCS 13-15
CT scan of the head is the diagnostic test of choice
Intracranial Hematoma, Hemorrhage
hematomas may develop above the dura (epidural), below the dura (subdural), and within the brain tissue itself (intracerebral)
Epidural hematoma
bleeding between the skull and the dura; 20-30% all hematomas; more often younger population; acute
rapidly developing symptoms:
headache, irritability/confusion, vomiting, ipsilateral pupil dilation (BEFORE decreased LOC), contralateral hemiparesis/hemiplegia, decreasing LOC
treatment: emergent surgery to evacuate the hematoma (burr hole), monitor and treat increasing ICP
Subdural hematoma
bleeding between the dura and the arachnoid membrane; 50-70% hematomas; usually elderly and alcoholics
s/s can be slower to present
acute: w/in 24 hours
subacute: within 2 weeks
chronic: more than 2 weeks
s/s: similar to epidural hematoma, but less vomiting and pupillary change does not precede change in LOC
treatment: assess for increased ICP, surgery to evacuate hematoma
Intracerebral Hematoma
bleeding within the brain tissue itself. May be d/t a gunshot wound, a severe acceleration-deceleration injury, or a laceration of the brain from a depressed skull fracture. May also be non-traumatic (stroke). 2-20% of hematomas
s/s vary greatly depending on the area of the brain that is involved.
treatment: surgery if the hematoma is large and the patient’s neuro status is deteriorating.
Types of skull fractures
- Linear - does not require surgery
- Open, depressed
If > 5mm below the inner table of the adjacent bone, surgeons will elevate the depressed skull fractures.
A comminuted skull fracture is a fracture with bone fragmentation, usually depressed. -
BASILAR
A linear fracture that occurs in the floor of the cranial vault (skull base), resulting in a meningeal tear.
s/s of a basilar fracture: raccoon eyes, rhinorrhea (CSF), Battle’s sign (bruising behind the ear), otorrhea - CSF from ear, damage to cranial nerve I (loss of smell)
Nursing r/t basilar skull fracture:
determine if nose or ear drainage is CSF. 1. Check for sugar. If positive, then it’s CSF. 2. Drainage on 4x4. If halo, then CSF.
Treatment:
1. do not block CSF drainage. No packing!
2. Surgery only if CSF leak is persistent.
3. monitor for meningitis.
4. No NG tube. Risk of penetrating brain.
Seizure management
Most are self-limiting, < 3min.
- Protect patient’s airway, turn on side.
- Maintain patient safety.
- Stop the seizure: Lorazepam (ativan) or Diazepam (Valium). Ativan preferred.
- Prevent seizure: Phenytoin (Dilantin), Fosphenytoin (Cerebyx), Carbamazepine (Tegretol), Phenobarbital
What is the benzodiazepine reversal?
Flumazenil (Romazicon)
Romazicon has a shorter half-life than some benzo’s, so may need to be readministered.
Status epilepticus
seizure activity (one or a series) > 5 min with no return to consciousness.
Death is due to cerebral hypermetabolism.
Bacterial meningitis vs Viral meningitis
Bacterial meningitis:
greatly increased protein, decreased glucose, greatly increased WBC’s, purulent CSF, lumbar puncture pressure > 180
Viral meningitis:
increased protein, normal glucose, increased WBC’s, clear CSF, lumbar puncture pressure normal
Signs of meningeal irritation:
Nuchal rigidity: flex the patient’s head to chest; if pain and stiffness, then nuchal rigidity is positive
Brudzinski’s sign: move patient’s chin to chest; if legs come up, then positive Brudzinski’s sign
Kernig’s sign: move patient’s legs up and out; if pain in neck and leg, then positive Kernig’s sign
Brain death
complete, irreversible cessation of function of the cerebrum, cerebellum, and brain stem
- confirm the following:
coma is irreversible & the cause is known
neuroimaging explains coma
effects of CNS drugs are absent (tox screen)
no evidence of residual paralytics
absence of severe acid-base, electrolyte, or endocrine abnormality
SBP >100
no spontaneous respirations - Clinical exam (by neurologist x2) of cranial nerves
- apnea test
management: provide support for the family, consider organ donation, hemodynamic support until donation
Apnea test in relation to brain death
If POSITIVE then supports brain death.
If NEGATIVE, then does not support brain death.
INDETERMINATE if test terminated before PaCO2 >/= 60 not achieved (or 20 over baseline)
Prerequisites:
core temp>36.5 C, SBP >90, PaCO2 >35, absence of respiratory depressing drugs, preoxygenation x20mins prior to ventilator disconnection, PaO2 may be normal or supranormal after the preoxygenation period
When to terminate:
Spontaneous respiratory movements are noted
SBP< 90
SpO2 < 85%
unstable cardiac arrhythmias
Guillain-Barre Syndrome (GBS)
An autoimmune response to a viral infection, recent vaccination, or surgical procedure. Demyelination of the lower motor neurons resulting in ASCENDING paralysis. The return of motor movement occurs proximally. Diaphragmatic involvement may result in ventilatory failure. No alteration of consciousness.
Treatment:
monitor vital capacity for impending respiratory failure - Intubation,
monitor urine OP for urinary retention,
corticosteroids,
IV immunoglobulin (IVIG) over 2-5 days,
plasmapheresis (if IVIG not used),
monitor for dysphagia
Myastenia Gravis (MG)
An autoimmune attack of the neuromuscular junction, resulting in “grave muscular weakness”
s/s:
progressive skeletal muscle weakness (early = easily fatigued, late = paralysis),
70% of patients have ocular dysfunction (ptosis, diplopia, difficulty closing an eye),
dysarthria, dysphagia
treatment:
1. Pyridostigmine (Mestinon) - an acetylcholinesterase inhibitor, prevents the breakdown of acetylcholine
2. Corticosteroids,
3. Immunosuppressants
4. Removal of the thymus gland
5. Plasmapheresis
IV immune globulin
