4 Stroke, part 1 Flashcards
Definition of “Time of symptom onset”
The last known time when the patient’s condition was at their baseline (i.e., “last known well” time)
*Not the time a patient was discovered with symptoms”
Not the time of awakening (if symptoms were noted upon awakening)
Top priority in stroke assessment
Assessment of airway, breathing, and circulation
What is Todd’s paralysis?
Seizure/postictal paralysis
Transient paralysis following a seizure, which typically disappears quickly
Can be confused with a transient ischemic attack
Note that seizures can be secondary to a cerebrovascular accident.
Blood glucose considerations in some of the prehospital stroke scales
Los Angeles Preshospital Stroke Screen
60- 400 mg/dL
Melbourne Ambulance Stroke Screen
50-400 mg/dL
Most widely used scale for documenting the severity of a stroke
National Institute of Health Stroke Scale (NIHSS)
- weighted toward the detection of anterior circulation strokes
- has a bias toward detection of left hemisphere strokes
Important scoring rules for proper use of the NIHSS
- Score what you see, not what you think
- Score the first response, not the best response (except in item 9, best language)
- Do not coach
Components of the NIHSS
1a Level of consciousness [LOC] (3)
1b LOC questions (2)
1c LOC commands (2)
—-
2 Best gaze (2)
3 Visual (3)
4 Facial Palsy (3)
—-
5a Motor arm, left (4)
5b Motor arm, right (4)
6a Motor leg, left (4)
6b Motor leg, right (4)
—-
7 Limb ataxia (2)
8 Sensory (2)
9 Best language (3)
10 Dysarthria (2)
11 Extinction and inattention (2)
Interpretation of the NIHSS score
0 - No stroke symptoms
1-4 - minor stroke
5-15 - moderate stroke
16-20 - moderate-to-severe stroke
21-42 - severe stroke
Remarks on anterior cerebral artery (ACA) infarction
Causes contralateral sensory and motor symptoms in lower extremity, with sparing of the hands and face
A left-sided ACA lesion is tyipcally associated with
akinetic mutism and transcortical motor aphasia (a nonfluent aphasia with greatly reduced spontaneous speech, but with retained autidory comprehension and repetition ability)
a right-sided ACA lesion is typically assocaited with
confusion and motor hemineglect
most commonly involved vessel in stroke
Middle cerebral artery (MCA)
Remarks on dominant hemisphere
In right-handed patients and in up to 80% of left-handed patients, the left hemisphere is dominant.
If the dominant hemisphere is involved, aphasia (receptive, expressive, or both) is often present.
If the nondominant hemisphere is involved, this may occur
inattention, neglect, extinction, dysarthria without aphasia, and constructional apraxia
Classic symptoms of posterior cerebral artery (PCA) stroke
(distal posterior circulation stroke)
Ataxia
Nystagmus
Altered mental status
Vertigo