Neurocritical Care
Serial neurologic examination
NIH Stroke Scale and/or GCS score
Score Range
Comments
Hunt and Hess
0 (no symptoms) to 5 (moribund)
Best correlated with risk of mortality
World Federation
of Neurological
Surgeons
1 (GCS score 15, no deficit) to 5 (GCS score 3β6)
Integrates risk of mortality and
motor dysfunction
Fisher
1 (no blood visualized) to 4 (diffuse SAH, ICH,
or intraventricular hemorrhage present)
Best correlated with risk of
vasospasm
CT scan of brain
Digital subtraction (βconventionalβ) angiography
May use CT angiography or magnetic resonance angiography if conventional angiography is unavailable
Transcranial Doppler, often daily during peak vasospasm risk period
INR
Troponin
ECG (electrocardiogram)
Echocardiogram
Causes β Typically caused by cerebral aneurysm. Modifiable risk factors for SAH:
Hypertension
Illicit drug use
Sudden death: Around 22%β26% of patients die before hospitalization. Inpatient mortality 13.1% in
2018 (United States).
Presence of blood in subarachnoid space elicits a chemical meningitis-type inflammatory response
and results in hemolysis of subarachnoid blood.
Vasospasm (persistent vasoconstriction) occurs, reducing distal cerebral blood flow.
Typical course is 3β14 days, but can occur out to 21 days post ictus.
ii.
Vasospasm risk peaks at around 7β10 days.
Several mechanisms of pathogenesis
Inflammatory infiltration