Neurological Emergencies Lecture Notes

Comprehensive vocabulary flashcards covering neurological anatomy, assessment findings, stroke pathophysiology, seizure types, and emergency pharmacology.

Stroke incidence in South Africa

Estimates suggest between $75,000$ and $132,000$ new cases annually and approximately $40,000$ deaths each year.

Central Nervous System (CNS)

Consists of the brain and spinal cord; receives and processes sensory information, initiates responses, stores memories, and generates thoughts and emotions.

Peripheral Nervous System (PNS)

Transmits information to and from the central nervous system, consisting of sensory neurons and motor neurons.

Autonomic Nervous System

Automatically regulates glands, internal organs, and blood vessels, pupil dilation, digestion, and blood pressure.

Somatic Nervous System

Carries sensory information and controls voluntary movement of the skeletal muscles.

Sympathetic Division

The "Fight or Flight" system that prepares the body to react and expend energy in times of stress.

Parasympathetic Division

The "Rest and Digest" system that maintains body functions under ordinary conditions and saves energy.

Cerebrum

The part of the brain that controls memory, intelligence, and muscles; divided into two hemispheres.

Cerebellum

Located in the posterior, inferior area of the skull; it manages complex motor activity, coordination, balance, and posture.

Brainstem

Consists of the medulla oblongata, pons, and midbrain; it controls basic vital functions like breathing, heart rate, and blood flow.

Medulla oblongata

Part of the brainstem that controls involuntary activities such as heart rate and breathing.

Midbrain

Part of the brainstem that regulates level of consciousness (LOC) and frees the cerebral cortex for higher activities.

Diencephalon

The part of the brain that filters out unneeded information.

Hypothalamus

The master controller of the endocrine system that controls homeostasis, pleasure, thirst, and hunger.

Amygdala

Part of the limbic system responsible for emotions, sensations of pleasure or fear, and recognition of fear in others.

Hippocampus

Part of the limbic system responsible for the formation of memories and memory conversion.

Trismus

Clenched teeth which may indicate a seizure in progress, severe head injury, or cerebral hypoxia.

Cushing reflex / Cushing’s Triad

Signs of increased intracranial pressure (ICP) consisting of hypertension, bradycardia, and irregular respirations.

Ptosis

The drooping or sagging of eyelids, which can be a sign of Bell palsy or stroke.

Hallucinations

Feelings of sound, sight, touch, and taste that are entirely within the patient’s mind.

Delusions

Thoughts or perceived abilities that are not based in a common reality.

Psychosis

An inability to determine what is real and what is inside one’s mind.

Corneal reflex

Tested by tapping between the patient's eyes; used to assume whether the cough or gag reflex is intact based on reflexive blinking.

Normal Blood Glucose Level

A reading between $3.4 - 6.7\,mmol/L$.

Hemiparesis

Weakness of one side of the body.

Hemiplegia

Paralysis of one side of the body.

Ataxia

An alteration of the ability to perform coordinated motions.

Myoclonus

Rapid, jerky muscle contraction that occurs involuntarily.

Dystonia

A condition where a part of the body contracts and remains contracted.

Paresthesia

The sensation of numbness or tingling.

Ischemic Stroke

Occurs when blood supply to areas of the brain is interrupted by a thrombus or embolus, causing ischemia.

Hemorrhagic Stroke

Resulting from a rupture of a vessel or an aneurysm, often described by the patient as the "worst headache of my life."

Cerebral Perfusion Pressure (CPP) Formula

$CPP = MAP - ICP$, where normal CPP is $70 - 80\,mmHg$.

Normal Mean Arterial Pressure (MAP)

$50 - 60\,mmHg$.

Normal Intracranial Pressure (ICP)

$0 - 10\,mmHg$.

FAST Mnemonic

Used to assess for stroke: Facial droop, Arm drift, Speech impairment, Time is critical.

Transient Ischemic Attack (TIA)

Episodes of cerebral ischemia without permanent damage that usually resolve within $24$ hours; often a warning sign of vascular problems.

Generalized Seizures

Seizures involving both hemispheres of the brain, commonly resulting in loss of consciousness; examples include Absence and Tonic-clonic seizures.

Absence Seizures (petit mal)

Common in children; characterized by brief staring spells lasting seconds with no postictal confusion.

Focal (partial) Seizures

Seizures that start in one area of the brain; categorized as simple focal (no loss of consciousness) or complex focal (impaired awareness).

Status epilepticus

Consecutive seizures occurring without consciousness or a single seizure lasting longer than $4$ to $5$ minutes.

Seizure Phases

Includes Aura (sensation before onset), Tonic (stiffening), Hypertonic (rigidity), Clonic (jerking), and Postictal (confusion/recovery).

Diazepam

A Schedule $5$ benzodiazepine acting on the CNS with anxiolytic, sedative, anticonvulsant, and muscle relaxant properties.

Flumazenil

A benzodiazepine antagonist used to reverse the sedative effects of benzodiazepines by competitive inhibition.

Lorazepam

A first-line anticonvulsant for status epilepticus; it has longer CNS activity than diazepam and must be stored at $2 - 8^{\circ}C$.

Midazolam

A water-soluble benzodiazepine used for sedation and anticonvulsive therapy, especially when IV access is unavailable (via IM route).