Neurology Flashcards
1
Q
Increased ICP signs
A
- Early: change LOC, HA, N/V, lethargy, irritability
- Late: pupillary changes, ipsilateral pupil change, seizure, posturing, coma
2
Q
Monitoring ICP
A
- Normal: 0-15 mmHg
- Calculate cerebral perfusion pressure:
MAP - ICP = CPP (70-90)
Goal >60 - Methods: intra-ventricular catheter (Drain excessive CSF & intermittently monitor ICP); intraparenchymal (monitor only, aka “bolt”)
- Who? early recognition of increased ICP, Head injuries - GCS <8, cerebral edema, large ischemic stroke, hydrocephalus
- Waveforms: P1 - percussion, P2 - tidal, P3 - dicrotic (closure of aortic valve); Normal P1>P2>P3
Increase P2 with decreased compliance/increased ICP
C wave “common”
B wave “bad”
A wave “awful” - cerebral spasm & high ICP
3
Q
Managing increased ICP
A
- Positioning for venous drainage: HOB 30-45, good head alignment/midline, straight legs
- Prevent jugular vein compression
- Decrease stimuli
- Manage pain
- Normothermia (fever–> worse outcome)
- Mannitol 20% (osmotic diuretic) - ulse filter, monitor osmilality, Na+ & K+
- Hypertonic saline
- Loop diuretics
- No higher than 320 mOm/L
- Monitor for rebound ICP increase
- CPP >60 mmHg
- Surigcal: Burr holes, decompressive craniectomy for refractory intracranial hypertension when all failed
4
Q
Diagnostics for stroke
A
- CT w/o contrast within 45 minutes to r/o hemorrhage
- CT perfusion or MRI perfusion: measures infarct core or penumbra
5
Q
tPA
A
- “Door-to-Needle” 60 minutes
- Symptom onset window: 4.5 hr
3hr if age>80, taking anticoagulation, history of stroke & DM, NIHSS >25 - Baseline lab: glucose, CBC, coag, chem, trop, 12 lead ECG
- Control BP prior to administration SBP<185, DBP <110
6
Q
Complications of tPA
A
- conversion to ICH: deteriorating neuro, HA, N/V, acute hypertension
- STAT CTH, coag, fibrinogen, CBC
- Transfusion platelet, cryoprecipitate, Transexamic acid (TXA) - antifibrinolytic, FFP
7
Q
Basilar skull fracture
A
- A fracture in the floor of the skull; risk of injury to the cranial nerves
- Avoid NG/OG, oral suctining
- Battle sign: ecchymosis on mastoid bone
- Raccoon eyes
- Rhinorrhea: torn blood vessels in the nose, CSF can leak - tear in meninges, salty taste from Na+ in CSF
- Otorrhea: test for glucose (positive in CSF), “Halo” fluid on gauze
- Pneumocephalus - air in head; HOB flat; high concentrated O2 to dissolve nitrogen in air
- Loss of sense of smell/damage to CN I (olfactory)
8
Q
Acute epidural hematoma
A
- Neuro emergency - arterial bleed; usually temporal or parietal region from laceration of the meningeal artery and/or vein
- S/S: Altered LOC, N/V, agitation, confusion, severe decompensation - uncal (lateral) herniation
9
Q
Uncal herniation
A
- uncus pressure on the tentorial notch
- compression of the midbrain
- change in LOC
- unilateral pupil dilation, contralateral hemiparesis, lateral displacement
10
Q
Brain stem hernation
A
- downward pressure towards brainstem and medulla
- Cushing’s Triad: 1. bradycardia, 2. systolic hypertension w/ wide pulse pressure, 3. irregular respiration
- small pupils
- ataxic respiration
- coma
11
Q
Brain death
A
- Must be normothermic
- Narcotics/sedatives cleared from the system
- Absence of EEG
- Absence of somatosensory evoked potential
- ICP>MAP
- Absence of cerebral perfusion: cerebral angiogram, CT angio, MRI
Everything is negative, except the apnea test.
- Oculocephalic reflex (doll’s eyes) - CN III, VI, VIII; normally eyes move with head turn
- Oculovestibular reflex (cold caloric test) - Normally look toward the stimulus
- Absent gag/cough
- Absent pupillary response
- Abnset corneal reflex
- Apnea Test: hyper oxygenate with 100% FiO2, remove ventilator, assess for absence of breathing
12
Q
Aneurysms
A
- Most occur in the Circle of Willis
- Rupture when >8-10 cm
- Dx: CT w/o contrast
- S/S: asymptomatic until rupture - sudden “worst headache of my life”, N/V, photophobia, diplopia, nuchal rigidity (Kernig’s and/or Brudzinski’s sign) from meningeal irritation, seizure, decrease in LOC, coma
- Tx: treat HTN (keep SBP 140-180), monitor re-bleed, monitor for cerebral artery vasospasm (transcranial doppler) and prevent with prophylactic CCB (Nimostop/Nimodipine for 1 month)
- Aneurysm clip or stent
13
Q
Status epilepticus
A
- Seizures more than 30 minutes
- patent airway
- Identify underlying cause: toxicology screen, assess electrolyte & glucose
- Benzodiazepines: Lorazepam (Ativan), Diazepam (Valium), Midazolam (Versed)
- Phenytoin (Dilantin) - monitor of bradycardia & hypotension, use filter
- Valproic acid, Fosphenytoin, Ketamin
14
Q
Guillain-Barre Syndrome
A
- An autoimmune disorder that attacks the peripheral nervous system
- Many follow from an illness or virus usually 1-3 weeks after
- Temporary damage to the myelin sheath - impulse travel slowly causing slow movement or ascending paralysis
- Monitor - Vital capacity for impending respiratory failure, UO for urinary retention
- Dx: LP
- Tx: plasmapheresis, IVIG, intubation, mechanical ventilation for respiratory failure, corticosteroid
15
Q
Meningitis
A
- Inflammation of meninges
- S/S: HA, fever, altered LOC, photophobia, photophobia, nuchal rigidity (+ Brudzinski’s, + Kernig’s)
- Dx: LP - viral vs. bacterial
16
Q
Brudzinski’s sign
A
severe neck stiffness when the knee and hip flex when the neck is flexed
17
Q
Kernig’s sign
A
severe stiffness of the hamstrings causes an inability to straighten the leg when the hip is flexed 90 degrees
18
Q
Viral meningitis
A
- CSF: + protein, normal glucose
- Lymphocytes
19
Q
Bacterial meningitis
A
- CSF: +++ protein, low glucose (CSF glucose/serum glucose <= 0.4)
- Neutrophils, WBCs
- Increased lactate
- Rash
20
Q
Autonomic Dysreflexia
A
- aka hyperreflexia
- a damaging event below the level of injury causes communication disruption between brain & body above level of injury
- Causes: bladder distension, UTI, constipation/fecal impaction
- S/S: sudden increase in BP, bradycardia, diaphoresis/sweating, piloerection, HA, visual changes, flushing, anxiety
- Tx: bowel & bladder training, treat BP
21
Q
Cerebral Perfusion Pressure
A
MAP - ICP
Normal 60-100
22
Q
Myasthenia Gravis
A
- Chronic auto-immune neuromuscular disease that causes progressive skeletal muscle weakness
Early: easily fatigued
Later: paralysis - 70% have ocular dysfunction - ptosis, diplopia, difficulty keeping eyes closed
- Dysarthria, dysphagia
- Acetylcholine receptors are blocked
Tx:
- plasmapheresis, IVIG
- Pyridostigmine (Mestinon) - acetylcholinesterase inhibitor; prevents cholinesterase from breaking down acetylcholine
- Corticosteroids/immunosuppressants
- Removal of the thymus gland
23
Q
Myasthenic Crisis
A
- D/t being undx/untx or acute exacerbation
- Deficiency of acetylcholine
- Tensilon test: Tensilon 2 mg IV → clinical improvement
24
Q
Cholinergic Crisis
A
- D/t overtreatment; excess of acetylcholine
Tensilon 2mg IV → increased muscle weakness (asked to hold arms out)→ SLUDGE
S - salivation
L - lacrimation
U - urination
D - defecation
G - gastrointestinal distress
E - emesis
