Neuro

Acute Severe Headache

BP Control in Ischemic vs Hemorrhagic Event

Stroke

BP Control in Ischemic vs Bleed

• Bleed: maintain BP <160 SBP or <110 MAP (once controlled give oral atenolol or amlodipine)
• Ischaemic Stroke: Treat if >220/120; don't reduce more than 15% of initial BP for 24 hours
• Ischaemic Stroke: if rTPA, treat if >185/110

Medication Choices: Labetalol, Nicardipine, Esmolol, Enalaprilat

• Labetalol: 20mg x 2 minutes, then 10mg every 10 minutes or 2-8mg/min (max 300mg)
• Nicardipine: 5mg/h, titrated up to 15mg/h by increasing 2.5mg/hr every 5 minutes
• Enalapril: 1.25mg IVP
• Nitroprusside: 0.5 mcg/kg/min IV infusion

Source: Medscape

Acute Severe Headache

1. SAH
2. Carotid/Vertebral Artery Dissection
3. Idiopathic Intracranial Hypertension
4. CVT (Cerebral Venous Thrombosis) including cerebral sinuses (sup sagittal, transverse sinuses)

Stroke

4 Risk Factors for ICH and less favorable outcome

(NINDS Reanalysis 2004)

1. Age >70

2. Baseline NIHSS >20

3. Glucose >16.7 mmol/L (>300mg/dL)

4. edema or mass effect on initial CT

Issues:

1. intraarterial TPA: up to 6 hours anterior circulation, up to 8 hours posterior circulation

2. resolving deficits, not completely: fluctuating neuro findings is typical of stroke, it does not mean

Absolute c/i (bloods)

1. <100K platelet

2. INR*: 15 seconds, 1.5 (and 1.7)

3. <2.7 mmol/L (stroke mimic) >22 mmol/L (higher risk of ICH)

- unusual scenario if hemiparesis + patient is wide awake in hypoglycemia

*Study, INR is normal if:

no warfarin

no heparin

no dialysis

no liver disease

no bleeding diathesis

What to look for CT brain

1. Blood: c/i

2. Completed infarction, large MCA hypodensity: caution for TPA

3. First signs: Blurring of gray-white mater in basal ganglia, lentiform nucleus, caudate, insula: good arguments for TPA

4. Hyperdense MCA sign: caution to interpret (lots of Hyperdense MCA sign)

To tell patient/family

1. If no consent, can still give

2. Hard to discuss with patient who's brain is stunned

3. Neurologic recovery: 25%

4. Bleed risk: 6%, brain and gut

AAEM:

NIHSS (National Institute of health stroke scale):

- measures severity of stroke on a 0-42, normal to worst scale

Stroke mimics

1. post-fit

2. migraine headache

3. ?hypoglycemia

TPA benefit:

- NINDS (national institute of neurologic disorders and stroke) trial: 8/18 recovers by 3 months without significant disability = 44%

- vs. 6/18 = or one-third recovers regardless of treatment

Risk

- NINDS trial: bleed (brain/GIT): 1/18 = 5.8% -- has 45% fatality rate

- using TPA liberally than recommended by NINDS protocol = higher ICH

- complications are more likely if >70yo, severe stroke >15, glucose >300mg/dL (16.6 mmol/L)

How to recognize bleed:

1. Sudden headache, vomit, deteriorates

2. Stop TPA

3. ICH

- 10 units of cryoprecipitate (patient lacks fibrinogen); TPA gobbles up fibrinogen

- PCC (prothrombin complex concentrate): none, 2,7,9,10 but no fibrinogen

- FVIIa: no

- platelets: probably

- neurosurgical standby probably not necessary unless there is intraventricular hemorrhage which may need shunt

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Posterior stroke:

1. nystagmus: bidirectional or vertical

(small scandinavian study: vertigo + persistent unidirectional nystagmus + >70yo = 1/4 posterior stroke)

2. walk

3. limb ataxia

4. confusion

Sources:

1. AAEM (pdf)

2. Emergency Medicine Cases podcast