Neurologic Emergencies for EMTs

Overview

Lecture covers neurologic emergencies for EMTs: anatomy/physiology review, headaches, stroke/TIA, seizures/status epilepticus, and altered mental status (AMS), plus assessment and prehospital care.

EMS Competencies and Scope

• Apply fundamental knowledge to assess and manage acutely ill neurologic patients.
• Topics: anatomy, presentations, and management of AMS, seizures, stroke/TIA, headache.
• Emphasis on rapid recognition, time-sensitive transport, and use of validated stroke scales.

Neuroanatomy and Physiology Review

• Brain controls breathing, speech, and body functions; three major parts: cerebrum, cerebellum, brainstem.
• Cerebrum: largest; conscious thought; divided into right/left hemispheres with contralateral control.
• Cerebellum: balance and coordinated movement; remember “BL” for balance.
• Brainstem: life-sustaining functions (breathing, BP, swallowing, pupillary constriction).
• Functional regions: frontal controls emotion/thought; middle sensation/movement; back processes sight.
• Speech mostly on left near mid-cerebrum; left processes/understands speech; right affects speech output.
• Nerves: 12 cranial pairs from brain; 31 spinal pairs from cord via foramen magnum; PNS comprises cranial and spinal nerves.
• Brain needs constant oxygen, glucose, normal temperature; irreversible damage in 4–6 minutes hypoxia.

Headaches: Types and Red Flags

• Tension: muscle contraction head/neck; stress-related; squeezing/dull ache; usually benign.
• Migraine: vascular size changes at brain base; throbbing/pulsating; unilateral; peri-orbital onset; nausea/vomiting; visual aura; hours to days.
• Sinus: pressure from fluid in frontal skull sinuses; nasal congestion, cough, fever; usually no prehospital care.
• Red flags: “worst headache,” thunderclap onset, headache with fever, seizures, AMS, or post-trauma.

Stroke and TIA

• Stroke (CVA): interrupted brain blood flow by clot or rupture; deficits reflect affected region.
• Ischemic stroke: ~87% of strokes; due to thrombosis (local clot on atherosclerotic plaque) or embolus (traveling clot).
• Hemorrhagic stroke: ~13%; intracerebral bleeding; often fatal; risks: severe hypertension, stress/exertion, alcohol use.
• Aneurysm: arterial wall weak point; high BP can rupture leading to hemorrhage.

Transient Ischemic Attack (TIA)

• Transient reduction in cerebral blood flow; stroke-like symptoms resolve within 24 hours.
• Strong warning sign for impending stroke; requires hospital evaluation even if symptoms resolve.

Stroke Assessment: Signs, Lateralization, and Mimics

• Common signs: facial droop; sudden unilateral weakness/numbness; ataxia; vision loss/blur/diplopia; dysphagia; decreased responsiveness.
• Speech: aphasia (left hemisphere); dysarthria/slurred speech (right hemisphere).
• Other signs: severe headache, confusion, dizziness, combativeness, restlessness, tongue deviation, apraxia/anomia.
• Left hemisphere stroke: aphasia, right-sided paralysis.
• Right hemisphere stroke: left-sided paralysis; intact comprehension; slurred output; neglect of affected side; delayed help-seeking.
• BP patterns in intracranial bleeding: rising BP may reflect intracranial pressure; falling BP indicates worsening global perfusion.
• Stroke mimics: hypoglycemia; postictal state; subdural/epidural bleeds (epidural arterial/rapid; subdural venous/gradual).

Seizures: Types, Features, and Causes

• Definition: surge of abnormal electrical activity; convulsions and/or altered consciousness.
• Generalized (formerly grand mal): unconsciousness; generalized tonic-clonic movements; apnea during event; <5 minutes typical; postictal state follows.
• Absence (generalized): brief LOC, blank stare, no motor activity; common in pediatrics; rapid recovery with memory gap.
• Focal onset aware: preserved awareness; numbness, weakness, dizziness, sensory auras; local twitching; seen with frontal lobe tumors.
• Focal onset impaired awareness: temporal lobe; altered awareness; lip smacking, eye blinking, isolated jerks, auras, hallucinations, fear, repetitive behaviors.
• Aura: pre-seizure warning; not universal; patients with history may recognize and self-protect.

Status Epilepticus

• Seizure >5 minutes likely progressing to status; or recurrent seizures without regaining consciousness; or >30 minutes continuous/recurrent.
• Requires ALS intervention and medication; EMT focus on airway, ventilation, rapid transport.

Altered Mental Status (AMS)

• Behavior deviates from patient’s normal; ascertain baseline when possible.
• Causes: hypoglycemia, hypoxemia, intoxication, delirium, overdose, head injury, brain infection, temperature abnormalities, poisoning.
• Delirium: severe change in mental abilities causing impaired thinking and decreased environmental awareness.

Patient Assessment and Management Approach

• Scene size-up: determine medical vs trauma; safety; standard precautions; consider spinal motion restriction.
• Primary assessment: find and treat life threats; rapid exam; set priorities based on LOC and XABCs (X = life-threatening bleeding).
• Decision: load-and-go vs on-scene; package and transport; obtain OPQRST, SAMPLE, vitals if able.
• Unresponsive: gather history from family/bystanders; include pupils, SpO2, blood glucose in vitals; seek timeline and events.

Stroke Scales and GCS

• Use validated stroke assessments; always include GCS.
• BE FAST mnemonic: Balance, Eyes (vision), Facial droop, Arm drift, Speech, Time.
• Other tools: Cincinnati Prehospital Stroke Scale (facial droop, arm drift, speech); Los Angeles Prehospital Stroke Screen; LAG (LOC, Arm drift, Gaze).
• GCS scoring: Eye (4), Verbal (5), Motor (6); 15 normal; 13–15 mild dysfunction; 9–12 moderate; ≤8 severe—prepare airway management.

Vital Signs, Cushing’s Triad, and Monitoring

• Significant intracranial bleeding elevates intracranial pressure causing slow pulse, erratic respirations, high BP, and pupil changes.
• This pattern is Cushing’s triad; indicates possible increased intracranial pressure.
• Reassess ABGs/ABCs, vitals, interventions; track trends in pulse, BP, respirations, GCS; notify receiving facility early.

Prehospital Care: Stroke, Seizure, Headache, AMS

• Stroke care: rapid transport to stroke center; maintain SpO2 ≥94%; oxygen only if hypoxic or in respiratory distress.
• Time goals: ideal hospital arrival within 3–4 hours from last known well; some literature allows up to 6 hours.
• Hospital uses head CT to exclude bleed; if no bleed, may receive thrombolytics; report last known well time.
• Seizure care: protect from harm; do not restrain; suction airway; oxygen as needed; consider spinal motion restriction if trauma suspected.
• Status epilepticus: suction, positive-pressure ventilation, rapid transport, ALS rendezvous if possible; focus interventions postictally.
• Headache care: red flags prompt concern; high-flow oxygen if tolerated; dark, quiet environment; avoid lights and sirens.
• AMS care: identify cause; spinal motion restriction if indicated; support airway and ventilation; transport to appropriate facility.

Key Terms & Definitions

• Atherosclerosis: fatty plaque buildup narrowing arteries; risk for thrombosis.
• Arteriosclerosis: hardening of arterial walls; increases rupture risk.
• Thrombosis: clot forming locally within a vessel.
• Embolus: traveling clot from a distant site.
• Aneurysm: focal arterial wall weakness prone to rupture.
• TIA: transient ischemic attack; temporary cerebral ischemia; resolves within 24 hours.
• Aphasia: impaired language comprehension or production; typically left hemisphere.
• Dysarthria: slurred speech due to motor speech impairment; often right hemisphere involvement.
• Ataxia: lack of muscle coordination affecting gait and balance.
• Postictal state: period after seizure with deep sleep, lethargy, confusion.
• Cushing’s triad: hypertension, bradycardia, irregular respirations indicating raised intracranial pressure.
• Delirium: acute disturbance in attention and awareness with cognitive changes.

Structured Comparisons and Tools

Common Seizure Causes and Medications

• Causes: epileptic disorder; tumors; infection/abscess; scar tissue; head trauma; stroke; hypoxia; electrolyte derangements; hypoglycemia; poisoning; stimulant overdose; alcohol/med withdrawal; febrile (pediatric).
• Medications for epileptic seizures: levetiracetam (Keppra), phenytoin, phenobarbital, carbamazepine (Tegretol), valproate (Depakote), topiramate (Topamax), clonazepam (Klonopin).

Action Items / Next Steps

• Use BE FAST and a stroke scale plus GCS on suspected stroke; document last known well.
• Check blood glucose, SpO2, pupils in all AMS; treat hypoglycemia per protocol.
• Prioritize rapid transport to stroke centers; limit on-scene time.
• Provide oxygen only if hypoxic or in respiratory distress; target SpO2 ≥94%.
• For seizures, clear environment, protect head, suction airway, ventilate if needed; prepare for ALS in status epilepticus.
• For red flag headaches, minimize stimuli; avoid lights/sirens; monitor for neurologic decline.
• Reassess ABCs, vitals, and GCS frequently; communicate trends to receiving facility.