L7: Coma

Question 1

Def of Conscioussness

Answer 1

Two components of conscious behavior.
1. Awareness: content of consciousness
2. Arousal: appearance of wakefulness

Question 2

Full consciousness

Answer 2

• An awake state in which one is aware of oneself and the environment.

Question 3

Wakefulness

Answer 3

A function of the ascending reticular activating system (ARAS)

Question 4

Awareness

Answer 4

A function of the cerebral cortex

Question 5

Levels of Arousal

Answer 5

Question 6

Levels of Arousal

• Alert

Answer 6

Appearance of wakefulness, awareness of the self and environment.

Question 7

Levels of Arousal

• Lethargy

Answer 7

Mild reduction in alertness

Question 8

Levels of Arousal

• Obtundation

Answer 8

◈ Moderate reduction in alertness.

◈ ↑↑ response time to stimuli

Question 9

Levels of Arousal

• Stupor

Answer 9

◈ Deep sleep

◈ patient can be aroused only by vigorous and repetitive stimulation.

◈ Returns to deep sleep when not continually stimulated

Question 10

Levels of Arousal

• Coma

Answer 10

• Sleep like appearance and behaviorally unresponsive to all external stimuli (Unarousable unresponsiveness, eyes closed)

Question 11

Other Names of Vegetative state

Answer 11

(Coma vigil)
(Apallic syndrome)

Question 12

Etiology of Vegetative state

Answer 12

◈ Traumatic brain injury

◈ Diffuse cerebral hypoxia

Question 13

Parts Damaged in Vegetative state

Answer 13

1. Both cerebral hemispheres
2. AND/OR the thalamus bilaterally

Question 14

Parts Spared in Vegetative state

Answer 14

1. Brainstem
2. Hypothalamus

Question 15

CP of Vegetative state

• History
• Perceptual & Self-Awareness
• Sleep-Wake Cycles
• Movement
• Eye Movement
• Brainstem Reflexes
• Respiratory Functions

Answer 15

Question 16

Etiology of Locked-in Syndrome

Answer 16

◈ Bilateral ventral pontine stroke
◈ Direct trauma to the ventral pons

Question 17

Parts Damaged in Locked-in Syndrome

Answer 17

Ventral Pons

Question 18

Parts Spared in Locked-in Syndrome

Answer 18

• Cerebral cortex & Reticular Activating System (RAS)
• Spinothalamic tract (Dorsal pons)
• Centers of Vertical gaze and blinking of eye (Midbrain)

Question 19

CP of Locked-in Syndrome

• History
• Perceptual & Self-Awareness
• Sleep-Wake Cycles
• Movement
• Eye Movement
• Brainstem Reflexes
• Respiratory Functions

Answer 19

Question 20

Def of Cerebral Edema

Answer 20

• Excess accumulation of water in the intra and/or extra cellular spaces of the brain

Question 21

Etiology of Cerebral Edema

Answer 21

1. Head injury
2. Allergic reaction
3. Stroke
4. Acute liver disease
5. Cardiac arrest

Question 22

Types of Cerebral Edema

Answer 22

Question 23

Pathophysiology of Vasogenic Cerebral Edema

Answer 23

Breakdown of tight endothelial junctions → ↑ capillary permeability → extracellular accumulation of fluids

(White matter 1ry affected)

Question 24

Etiology of Vasogenic Cerebral Edema

Answer 24

◈ Ischemic stroke (late stages)

◈ Traumatic brain injury (early stages)

◈ Space occupying lesion (Tumor, abscess, Hge)

◈ Inflammation

Question 25

BBB integrity in **Vasogenic Cerebral Edema**

Answer 25

Breakdown

Question 26

Pathophysiology of **Cytotoxic Cerebral Edema**

Answer 26

- Damage to brain parenchyma cells → impaired Na+/K+ ATPase function → intracellular accumulation of Na+, fluids → expansion of neurons, glial, and endothelial cells **(Grey matter 1ry affected)**

Question 27

Etiology of **Cytotoxic Cerebral Edema**

Answer 27

◈ Ischemic stroke (early stages) ◈ Traumatic brain injury (late stages) ◈ Various toxins (Hyperammonemia) ◈ Reye’s syndrome ◈ Severe hypothermia

Question 28

BBB Integrity in **Cytotoxic Cerebral Edema**

Answer 28

Intact

Question 29

Pathophysiology of **Interstitial Cerebral Edema**

Answer 29

- Blocked CSF drainage → ↑ ventricular pressure → movement of Na+ & water across the ventricular wall into the paraventricular (interstitial) space

Question 30

Etiology of **Interstitial Cerebral Edema**

Answer 30

◈ Hydrocephalus ◈ Idiopathic intracranial hypertension

Question 31

BBB Integrity in **Interstitial Cerebral Edema**

Answer 31

Intact

Question 32

Pathophysiology of **Osmotic Cerebral Edema**

Answer 32

Osmolarity of plasma > intracerebral → osmotic gradient → water diffusion across BBB into interstitial fluid

Question 33

Etiology of **Osmotic Cerebral Edema**

Answer 33

◈ Hypernatremia (SIADH) ◈ Iatrogenic (rapid correction of hyperglycemia in DKA or hypernatremia)

Question 34

BBB Interity in **Osmotic Cerebral Edema**

Answer 34

Intact