Key Concepts
Introduction
Stroke results from either cerebral vessel occlusion (ischemic, 87% of cases) or rupture (hemorrhagic), causing acute neurological deficits corresponding to the affected vascular territory. Ischemic stroke triggers an ischemic cascade: neuronal energy failure leads to glutamate release, NMDA receptor activation, calcium influx, and activation of destructive enzymes (calpains, caspases) causing cell death — the ischemic penumbra is potentially salvageable tissue surrounding the infarct core that is the target of thrombolytic therapy (alteplase within 4.5 hours). Traumatic brain injury involves primary injury (direct mechanical damage) and secondary injury (cerebral edema, ischemia, excitotoxicity, and neuroinflammation that evolve over hours to days). The nurse managing neurological emergencies must perform serial neurological assessments using the Glasgow Coma Scale, monitor for signs of increased ICP (Cushing's triad: hypertension, bradycardia, irregular respirations), and implement neuroprotective interventions. On the exam, writers often pair stable-sounding options with unstable data—notice the mismatch before you commit. If the stem names a license or role, reread that line; scope errors are classic trap answers even when the clinical topic is familiar. Run a 60-second scan: breathing work and oxygenation, perfusion and...