Neurology: Altered Mental Status and Seizures

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Questions and Answers

What is the primary characteristic of the penumbra in ischemic strokes?

It consists solely of necrotic cells.

It is the area of the brain that has sufficient blood flow.

It's the completely infarcted tissue.

It is the area that is hypo-perfused and potentially salvageable. (correct)

Which of the following is a common cause of small vessel occlusion?

Embolic events.

Trauma to the artery.

Inflammatory conditions.

Thickening of artery walls. (correct)

Which symptom is NOT typically associated with small vessel occlusion?

Hemiparesis.

Ataxia.

Dysarthria.

Visual field deficits. (correct)

What percentage of ischemic strokes is attributed to large vessel occlusion?

50%. Signup and view all the answers

Which of the following is a common underlying cause of large vessel occlusion?

Extracranial artery atherosclerotic embolism. Signup and view all the answers

Which of the following conditions is NOT a known cause of unprovoked seizures?

Alcohol withdrawal Signup and view all the answers

What is a characteristic feature of focal onset seizures?

They are limited to one hemisphere at onset. Signup and view all the answers

What type of seizures might occur due to an immune response causing central nervous system inflammation?

Autoimmune seizures Signup and view all the answers

What is the main purpose of the classification created by the International League Against Epilepsy?

To facilitate communication in clinical care and research Signup and view all the answers

Which of the following metabolic imbalances can potentially precipitate seizures?

Hypernatremia Signup and view all the answers

In the context of seizures, the term 'impaired awareness' refers to:

Being unaware of the environment at any point during the seizure. Signup and view all the answers

Which phrase best describes 'motor' symptoms in seizures?

Motor activity is limited to one side of the body. Signup and view all the answers

Which of the following is NOT classified as a known toxin that can lead to seizures?

Beta-blockers Signup and view all the answers

What is the primary goal of early identification in stroke treatment?

To ensure timely transport to a specialized hospital Signup and view all the answers

Which imaging technique is preferred for showing hemorrhage in the brain?

Non-contrast CT Signup and view all the answers

What is the time window for administering thrombolysis in ischemic stroke patients?

Up to 4.5 hours after symptom onset Signup and view all the answers

Which of the following aspects helps determine the treatment pathway in a stroke?

Type of imaging conducted Signup and view all the answers

What is a risk associated with thrombolysis treatment for ischemic stroke patients?

Potential for ongoing hemorrhage Signup and view all the answers

What is the purpose of a CT perfusion scan in stroke assessment?

To measure cerebral blood flow and volume Signup and view all the answers

Which treatment option is suitable for large vessel occlusions (LVOs)?

Endovascular clot retrieval Signup and view all the answers

What should be monitored concerning blood pressure before administering thrombolysis?

Should be lower than 185 mmHg Signup and view all the answers

Which treatment should be avoided in managing a patient with haemorrhagic stroke?

Administering narcotic analgesia Signup and view all the answers

What is a common life-threatening cause of secondary headaches?

Head trauma Signup and view all the answers

In the context of neurogenic shock, which statement is accurate regarding sympathetic tone?

Sympathetic tone is lost entirely below T6. Signup and view all the answers

What is the purpose of osmotherapy in conservative treatment of haemorrhagic stroke?

To reduce intracranial pressure Signup and view all the answers

Which of the following is NOT a common associated condition of haemorrhagic stroke?

Chronic respiratory disease Signup and view all the answers

What percentage of head elevation may help decrease intracranial pressure during treatment?

30 degrees Signup and view all the answers

Which of the following medications is typically used as an antiemetic in handling headaches?

Prochlorperazine Signup and view all the answers

Which of the following accurately describes the hemodynamic changes in neurogenic shock?

Normal blood volume with hypotension Signup and view all the answers

What serious condition can occur due to fluctuations in drug levels in Parkinson's patients?

Severe hyperpyrexic emergency Signup and view all the answers

What is the typical time frame for respiratory failure and death in patients with ALS after symptom onset?

2-5 years Signup and view all the answers

Which age group has the predominant onset of Multiple Sclerosis (MS)?

Young adults (20-40 years) Signup and view all the answers

What progressive symptom is primarily associated with Myasthenia Gravis?

Episodic muscle weakness Signup and view all the answers

What condition is associated with severe rigidity and altered consciousness in Parkinson's patients?

Hyperpyrexic emergency Signup and view all the answers

In patients with ALS, which muscles are most severely affected as the disease progresses?

Respiratory muscles Signup and view all the answers

Which statement accurately describes the nature of Multiple Sclerosis?

It leads to irreversible degeneration of the myelin sheath. Signup and view all the answers

What is a common early sign of Myasthenia Gravis?

Eye weakness Signup and view all the answers

Study Notes

### Altered Mental Status

Altered mental status can result from a range of causes including:
- Infections: Meningitis, encephalitis, cerebral malaria
- Head Injury: Subdural hematoma, penetrating head injury, concussion, neurosurgery
- Alcohol & Medication Withdrawal: Occurs in 7-48 hours after last dose/drink
- Metabolic: Hypo/hyperglycemia, hypo/hypernatremia, hypocalcaemia
- Toxic: Cocaine, antidepressants, antipsychotics, antihistamines, analgesics, alcohol intoxication (more common in overdose)
- Other: Eclampsia, febrile seizures, cerebral hypoxia

Seizures

Unprovoked Seizure: Occurs in the absence of precipitating factors.
Epilepsy:
- Causes of Epilepsy
  - Genetic: Chromosomal or genetic abnormality.
  - Metabolic: Genetic metabolic disorders (e.g., cerebral folate deficiency)
  - Immune: Immune response causing central nervous system inflammation (different from infectious, due to antibody mediation).
  - Infectious: Meningitis, encephalitis, cerebral malaria
  - Structural: CVA/stroke, TBI, tumors, vascular malformations, scarring from cerebral hypoxia

Stroke

Classification:
- ILAE (International League Against Epilepsy) Classification of Seizures:
  - Focal Onset: Unilateral, limited to one hemisphere at onset.
    - Aware: Patient is fully aware during the seizure.
    - Impaired Awareness: Awareness is impaired at any point during the seizure.
    - Motor: Ipsilateral tonus or clonus present (one side of the body).
    - Non-motor: No motor activity, presents with sensory, cognitive, autonomic, emotional, or behavioral arrest.
Penumbra: The salvageable portion of the brain surrounding the ischemic core. Approximately 1.9 million neurons die per minute in the hypo-perfused ischemic penumbra.
Small Vessel Occlusion: Occlusion of small cerebral arteries supplying deeper brain structures (¼ of ischemic strokes).
- Predominantly caused by:
  - Thickening of artery walls & hypertrophy of smooth muscle, narrowing the vessel.
  - Atheroma & stenosis.
  - Emboli (uncommon).
- Symptoms:
  - Hemiparesis (one-sided weakness)
  - Dysarthria (difficulty speaking with motor function)
  - Altered sensation
  - Ataxia (discoordinated movements & trouble walking).
Large Vessel Occlusion (LVO): Occlusion of any of the large cerebral arteries or intracranial vessels, including the basilar artery (BA), the internal carotid artery (ICA), and the middle cerebral artery (MCA) (approximately 50 % of ischemic strokes).
- Some definitions include:
  - Posterior cerebral artery (PCA), anterior cerebral artery (ACA), and vertebral artery (VA).
- Around 80% affect anterior circulation.
- Causes:
  - Primary atherosclerosis
  - Extracranial artery atherosclerotic embolism
  - Cardioembolic events (atrial fibrillation)
  - Cryptogenic (unknown).
LVOs contribute disproportionately to mortality & morbidity.
If a mimic cannot be entirely ruled out, a stroke must be considered.
Treatment of Stroke:
- Early identification
- Timely transport to an appropriate hospital with notification (stroke unit & reperfusion therapies).
- Monitor BP.
- Consider:
  - Large bore IV cannula
  - MICA for intubation of the unconscious patient
  - Antiemetics to minimize gagging & vomiting
  - Treat seizures with benzodiazepines/midazolam
  - Oxygen in the hypoxic patient
Definitive Assessment: Brain imaging:
- Shows ischemic VS hemorrhagic.
- Aids decision of treatment pathway & timeline.
  - Non-contrast CT: Shows hemorrhage & some mimics (favoured, available but not good at identifying posterior circulation strokes).
  - CT angiogram: Contrast dye shows image of cerebral vessels, showing which artery is occluded during an ischemic stroke.
  - CT Perfusion: Measured cerebral blood flow & cerebral blood volume within cerebral tissues. Shows the penumbra & core of the stroke using dye.

Stroke Treatments

Ischemic Stroke Treatment:
- Thrombolysis:
  - Tenecteplase or alteplase are most commonly used.
  - Used in all ischemic stroke patients within 4.5 hours of symptom onset.
  - If CT perfusion imaging shows salvageable penumbra, thrombolysis can be administered up to 9 hours post-symptom onset.
  - Less successful in LVOs, but should be given in conjunction with ECR.
- Endovascular Clot Retrieval (ECR):
  - Technique where a catheter is inserted into the groin & femoral artery, under x-ray, to locate the clot, cross through the clot, and capture it with a mesh cage, using vacuum suction to pull out & remove the clot.
  - Only able to treat LVOs and should be considered up to 24 hours post symptom onset.
  - Improved 90-day functional independent rates from 13-50%.
  - Only available at specific hospitals.
Haemorrhagic Stroke Treatment:
- Conservative Treatment:
  - Maintain balance of BP.
  - Osmotherapy & hyperventilation can be trialled in those with edema or increased ICP.
  - BGLs kept in normal range.

Headache

Red Flags for Primary Headaches:
- Age of onset >40 years.
- Other associated conditions or features (head trauma, illicit drug use, toxic exposure, headache on awakening, precipitated by cough/exertion/sexual activity).
- Previous headache history with progression or change in frequency, severity, or clinical features.
Life-Threatening Causes of Secondary Headaches:
- Trauma to the head or neck
- CVA or cerebral vasculitis
- Tumors & increased ICP
- Seizures
- Medications or positions (Nitrates = vasodilation, carbon monoxide)
- Infections (meningitis, encephalitis)
- Hypertension, dehydration, renal or thyroid problems.
Treatment:
- Gentle handling, reduce stimulus (lights, noise, sirens).
- Non-narcotic analgesia (paracetamol).
- Antiemetics (prochlorperazine)
- Raise the head of the stretcher 30 degrees to help decrease ICP.
- Transport to a neuro centre if the patient has any red flags.

Neurogenic Shock

Shock occurring in the setting of normal blood volume (normovolemic hypotension).
Refers to the hemodynamic instability that occurs in the setting of a spinal cord injury at the level of T6 & above, and is related to the loss of sympathetic tone to the peripheral vasculature & heart.
Significant loss of sympathetic division past T6, but large preservation of parasympathetic, leaving the spinal column much higher than the level of injury. The result being that the loss of sympathetic tone prevents the usual ability to control the peripheral vascular and increase the firing rate & contraction of the heart.
Involves the loss of innervation to the Celiac ganglion, which results in an inability to stimulate the adrenal glands to release catecholamines (adrenaline & noradrenaline) with resulting loss of vascular tone and decreased inotropy (contractility) & chronotropy (heart rate).

Parkinson's Disease

Fluctuations in drug levels can lead to an acute exacerbation of Parkinson symptoms.
Sometimes patients can experience a severe, hyperpyrexic emergency with altered consciousness, severe rigidity & rhabdomyolysis, which can be fatal if not treated urgently.
Patients can have acute psychotic episodes, especially with concomitant infections.
Patients may have dystonic reactions due to the medications taken to manage their symptoms.

Amyotrophic Lateral Sclerosis (ALS)

Due to the steady, progressive and irreversible degeneration of upper & lower motor neurons.
Involved progressive muscle weakness, leading to respiratory failure & death, usually within 2-5 years of onset.
Muscles atrophy as a result of disuse (secondary to the loss of nerve innervation) and as the disease progresses, it eventually reaches the respiratory muscles.
Patients become apnoeic (unless ventilated) and this is the reason they may be encountered in the prehospital setting.
Can also be called ‘Lou Gherigs disease’, but was also the cause of Stephen Hawking’s disability.

Multiple Sclerosis (MS)

Steady, progressive & irreversible degeneration of the myelin sheath, primarily in the CNS.
MS is the most frequent cause of permanent disability in young adults, aside from trauma, with onset predominantly in the 20-40 year age group.
Though the exact cause remains unclear, it is thought to be an autoimmune disorder, and links to the human leukocyte antigen (HLA) complex responsible for numerous immune functions.
MS ‘attacks’ or ‘flare ups’ vary widely, ranging from generalized weakness and paralysis to balance issues, to paraesthesia or vision problems.

Myasthenia Gravis

A chronic autoimmune disorder characterized by the destruction of nicotinic Ach receptors at the postsynaptic neuromuscular junction (destroy the communication between the nerves & the muscles they innervate).
Results in weakness of the voluntary skeletal muscles of the body, especially those controlling the eyes, mouth, & limbs.
Symptoms include episodic muscle weakness & easy fatigability, which worsens with activity & decreases with rest.
Eye weakness is very common & is often the first sign.
Myasthenic crisis occurs when respiratory muscles are affected & hypopnea or apnea occurs.

Altered Mental Status (Syncope)

Syncope:
- Definition: A transient loss of consciousness due to a decrease in blood flow to the brain, typically caused by a drop in BP.
- Common Causes:
  - Vasovagal syncope: A sudden, temporary drop in BP and HR due to a trigger, often emotional stress.
  - Orthostatic hypotension: A drop in BP upon standing, often caused by dehydration or medications.
  - Cardiac syncope: A drop in BP due to a problem with the heart, such as arrhythmia or valve dysfunction.
Assessment:
- History: Gather details about the syncopal event (symptoms, triggers, duration, prior episodes).
- Physical Exam: Check for signs of injury, vital signs (BP, HR), and neurological status.
- Electrocardiogram (ECG): To rule out cardiac causes.
- Other Tests: May be necessary depending on the suspected cause, such as an echocardiogram or tilt table test.
Treatment:
- Immediate Action: Position patient supine, elevate lower extremities to increase blood flow to the brain.
- Oxygen Administration: To increase blood oxygen levels.
- Fluid Resuscitation: To improve blood pressure and circulation.
- Transport: If symptoms persist or the cause is unclear, transport to the nearest appropriate facility.

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Description

This quiz covers crucial topics in neurology, focusing on altered mental status and seizure disorders. Explore various causes ranging from infections, and head injuries to metabolic and toxic factors affecting mental health. Additionally, understand the different types of seizures and the underlying factors contributing to epilepsy.