Neurology Flashcards
Erb-Duchenne Palsy
- ## Brachial plexus injury: C5+6 → effects musculocutaneous + axillary n. and esp suprascapular n. → paralysis of rotator cuff + biceps + brachialis + coracobrachialis + deltoid
Klumpke’s Palsy
- Brachial plexus injury: C8+T1 → effects ulnar, median, and radial n. → paralysis of all intrinsic muscles of hand
GCS Status
Eye Opening (E) 4 = spontaneous 3 = to voice 2 = to pain 1 = none
Verbal Response (V) 5 = normal conversation 4 = disoriented conversation 3 = words, but not coherent 2 = no words, only sounds 1 = none
Motor Response (M) 6 = normal 5 = localized to pain 4 = withdraws to pain 3 = decorticate posture (rigidity, clenched fists, legs held straight out, arms bent inward toward the body, wrists + fingers bend and held on the chest) 2 = decerebrate (rigidity, arms + legs held straight out, toes pointed downward, head + neck arched backwards) 1 = none
Severe: GCS 3-8
Moderate: GCS 9-12
Mild: GCS 13-15.
Physical - Primitive Reflexes
Rooting
- Rooting: turns head toward your finger when you touch the cheek.
- Sucking: sucks on your finger when you touch roof of mouth.
- Startle (Moro): support head in midline position with one hand and buttocks with the other. Quickly drop your hand supporting the head ~10cm below its original supporting position and then catch the head. Should see thigh + knee flexion, fan and then clench fingers, with arms first thrown outward and then brought together as though embracing something.
- Should be gone by 4 mos - Palmar + Plantar Grasps: gasps your finger when you stroke it against the palm of hand or plantar surface of foot.
- Asymmetrical Tonic Neck Response: turning head to one side causes gradual extension of arm toward direction of infant’s gaze with contralateral arm flexion (like a fencer).
- Stepping Response: legs make a stepping motion when you hold him vertically above the table and stroke the dorsum of foot against table edge.
- Babinski Response: dorsiflexion of big toe + fanning of other toes from stroking the lateral aspect of the foot’s plantar surface.
- Should be gone by 1-2 yrs.
Stroke
Sub-types
- Ischemic (80%): thrombosis, embolism, or hypertensive vasospasm
- Hemorrhagic (20%)
a. Subarachnoid: BV rupture, worst HA of life
b. Intracranial: htn, amyloid
Etiology
- 40% may be idiopathic (up to ½ of these may be from PFO or ASD)
- 75% atherosclerosis (esp htn)
- 25% cardiogenic (esp afib, but also mech valve, congenital, LV thrombus from ant MI)
- also: hypercoagulable, carotid dissection, aneurysm, atrial myxoma, migraine vasoconstriction
Pathophys
- Infarct core - irreversibly damaged area from the first few mins-hrs of ischemia
- Penumbra - potentially viable brain tissue surrounding infarct core -> restore blood perfusion to salvage this area
- Most damage = 3-6 hrs post-stroke
- Unilateral
Ddx
- Sz, hypoglycemia, metabolic issue, complicated migraine, brain tumour, functional illness
Prevention
- Risk factors: smoking, htn, hyperlipids
- ACE-I, statins
- D/C hormone replacement for post-menopausal women
- ASA if >=10% risk for 1st CAD episode
- Anticoagulation for atrial fib (or anti-platelet if bleed risk)
- Check for carotid bruits for carotid artery stenosis. Get emarterectomy if >60% stenosis dec annual stroke risk by ½
P/E
- Focal findings referable to a fixed distribution:
- > ACA: contralateral leg weakness
- > MCA: contralateral face + arm weakness > leg weakness. Sensory loss, field cut, aphasia, or neglect.
- > PCA: contralateral field cut
- > Deep penetrating arteries: contralateral motor or sensory deficit w/o cortical signs
- > Basilar artery: oculomotor deficit and/or ataxia with crossed sensory/ motor deficits - 1 side of face, opposite side of body. If the area of this artery in the ventral pons is affected, pt will have preserved consciousness, but only be able to open + close eyes
- > Vertebral artery: lower CN deficits (dysphagia, dysarthria, tongue/ palate deviation), and/or ataxia with crossed sensory deficits.
- MCA = most commonly occluded artery, classic stroke
Imaging/ Investigations
- Blood sugar (hypoglycemia can mimick stroke)
- Imaging required to distinguish stroke sub-types. CT uninfused always first (dye is also white), then CT angio/CT infused or carotid US.
- Note: suspicion of SAH + negative CT -> CSF from LP for erythrocytes or xanthochromia
- Duplex US of the carotid arteries w/i 2 days to assess for stenosis -> carotid endarterectomy.
- ECG, holter/ telemetry, ECHO if suspected cardiac cause (mostly looking for any sign of afib)
- PT, PTT, platelet count: possible anti-coagulation
- CBC: ensure adequate O2 carrying capacity
- Glc, Cr, BUN, lipids, LEs: underlying risk factors
- Sometimes investigate: hypercoagulability, vasculitis, blood cultures (febrile, ?endocarditis), neurosyphilis, hemoglobinopathies, lymphoproliferative diseases
Tx
- Blood sugar: give insulin >12
- IV fluids: NS (not dextrose to avoid hyperglycemia)
- Htn control:
-> No TPO: do NOT treat htn for 1wk unless >220/120 bc need cerebral perfusion. Exceptions: ACS, HF, dissection, AKI, or htn encephelopathy -> IV nicardipine or labetaolol -> dec BP by 15% over 1st day, and then continue cautiously
-> TPO:
_____missing_____
- Long-term: dec BP (<140/90), statin, smoking, alcohol, sedentary, anti-platelet (ASA, plavix), +/- anti-coagulation, HbA1c
Prognosis
- TPA does NOT affect mortality! Just may inc functionality.
- ABCD2 score
Transient Ischemic Attack (TIA)
- Temporary disruption of cerebral blood flow -> mimics stroke but resolves in 30MINS and no ischemic brain changes on imaging
- Up to 40% will eventually have a stroke, 20% in 90 days (risk stratification via ABCD2)
- Inc risk of recurrent events: >10 mins, limb weakness, speech disturbance, DM, >60 yro
Encephalopathy
- Lactulose
Dec LOC - DIMS
D: drug overdose/ withdrawals
I: infection/ infarction
M: metabolic (ie hypoglycemia, DKA - check glc, Na, Ca, CO2, O2, cortisol, TSH)
S: structural, ex stroke.
Inc ICP
S+S
- HA, N/V, dec LOC
- Cushing’s reflex/ triad: dec HR, inc BP, irregular breathing
Ddx
- Intracranial hemorrhage
-
Migraine
S+S
- Classic aura only occurs in ~30%
Tx
- Maxeran
Sub-arachnoid Hemorrhage
Etiology
- 80% from aneurysms. Also AVM, hemiangioma, blood dyscrasia, trauma.
S+S
- 40-60 yrs
- Worst headache of your life/ thunderclap
- N+V
- ½ report a bad HA in the previous ~2 wks (often a sentinel bleed)
- Be careful, sx can sometimes resolve after an hr/ with some maxeran - still CT!
Investigations
- CT: try to get it <6 hrs otherwise less sensitive, star pattern of white bleeding in circle of willis, can be subtle
- LP: looking for rbcs, xanthochromia
Prognosis
- Better than ischemic
- 15% die at home, 50% mortality at 6 mos
Meningitis
Etiology
- Can be bacterial (what we worry about), viral, fungal
- H.influenza (dec bc vaccine), Neisseria meningoccocus, Listeria, pseudomoas, gram -, staph aureus, noscomial
S+S
- Triad: fever + HA + nuchal rigidity.
- Maybe also vomiting, sz
- Kernig’s/ Brudzinski’s/ jolt tests
- More subtle in geriatrics, peds, immunosup
- BUT can’t r/o meningitis clinically
Investigations
- LP: bacterial -> WBC >1000, >80% neutro, dec glc, inc protein. Viral -> WBC <15% neutro, N glc/ protein
Tx
- Broad abx sooner than later
CT vs LP
Can do LP first IF: normal LOC, no papilledema (hard to see), no signs of inc ICP
Status Epilepticus
Criteria
- > = 5 mins of:
- > Continuous clinical and/or EEG sz activity
- > Recurrent sz activity w/o returning to baseline bw sz
Tx
- Dilantin
- Benzo (lorazepam, diazepam/ valium)
Cerebral Pontine Myelinolysis (CPM)
Pathophys
- See grand rounds slides
S+S
- Flaccid paralysis, dysarthria, dysphagia
Target: inc Na to 120 mmol/L at a rate of 1-2 mmol/L/hr, and then by 0.3-0.5 mmol/L/hr.
