Vomiting and drowsiness occur in some cases with increased intracranial pressure (ICP), and headache is common. Signs and symptoms are often not confined to a single vascular territory. Etiologies are diverse but hypertension related is the most common (Table 17-2). Hypertensive hemorrhages typically occur in the following locations:
- Putamen: contralateral hemiparesis often with homonymous hemianopia
- Thalamus: hemiparesis with prominent sensory deficit
- Pons: quadriplegia, “pinpoint” pupils, impaired horizontal eye movements
- Cerebellum: headache, vomiting, gait ataxia
A neurologic deficit that evolves gradually over 30-90 min strongly suggests intracerebral bleeding.
Treatment: Stroke Principles of management are outlined in Fig. 17-1. Stroke needs to be distinguished from potential mimics, including seizure, migraine, tumor, and metabolic derangements. - Imaging. After initial stabilization, an emergency noncontrast head CT scan is necessary to differentiate ischemic from hemorrhagic stroke. With large ischemic strokes, CT abnormalities are usually evident within the first few hours, but small infarcts can be difficult to visualize by CT. CT or MR angiography (CTA/MRA) may help reveal vascular occlusions. Diffusion-weighted MRI has a high sensitivity for identifying ischemic stroke even minutes after onset.
ACUTE ISCHEMIC STROKE Treatments designed to reverse or lessen tissue infarction include: (1) medical support, (2) intravenous thrombolysis, (3) endovascular revascularization, (4) antiplatelet agents, (5) anticoagulation, and (6) neuroprotection. MEDICAL SUPPORT Optimize perfusion in ischemic penumbra surrounding the infarct. - Blood pressure should never be lowered precipitously (exacerbates the underlying ischemia), and only in the most extreme situations should gradual lowering be undertaken (e.g., malignant hypertension with bp > 220/120 mmHg or, if thrombolysis planned, bp > 185/110 mmHg).
- Intravascular volume should be maintained with isotonic fluids because volume restriction is rarely helpful. Osmotic therapy with mannitol may be necessary to control edema in large infarcts, but isotonic volume must be replaced to avoid hypovolemia.
- In cerebellar infarction (or hemorrhage), rapid deterioration can occur from brainstem compression and hydrocephalus, requiring neurosurgical intervention.
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