Case 10

Question 1

What are the two phases of sleep?

Answer 1

Rapid Eye Movement (REM) sleep and Slow wave sleep (non-REM).

Question 2

What is non-REM sleep?

Answer 2

Muscle tension and movement reduced, although movement is still possible for changing position. Increased parasymapthetic activity causes decreased HR, respiration and kidney function. Idling brain in moving body.

Question 3

What is REM sleep?

Answer 3

Active hallucinating brain in paralysed body. Brain activity has fast and low voltage EEG and higher oxygen consumption than an awake and concentrating brain. Body incapable of movement except for respiratory muscles, eye mscles. Stimulated by acetylcholine secretion and inhibited by serotonin.

Question 4

What percentage of sleep is spent in REM phase?

Answer 4

about 25%.

Question 5

What is consciousness defined as?

Answer 5

Alert cognitive state in which you are aware of yourself and your situation

Question 6

What is a coma?

Answer 6

State of unarousable unresponsivness, caused by damage to either the diencephalon/midbrain or the hemispheres.

Question 7

What is toxic-metabolic encephalopathy?

Answer 7

Acute brain dysfunction with symptoms of delirium or confusion, usually reversible, causes systemic illness, infection, organ failure, and other conditions.

Question 8

What is locked-in syndrome?

Answer 8

Awareness, sleep-wake cycles meaningful behaviour (eye movements) but quadripelgia and pseudobulbar palsy.

Question 9

Minimally Conscious State?

Answer 9

Intermittent periods of awareness and wakefullness, display some meaningful behaviour.

Question 10

Persistant vegetitive state?

Answer 10

Sleep wake cycles, lacks awareness, only displays reflexes and non purposful behaviour, classified as permanent after 1 year.

Question 11

Chronic Coma?

Answer 11

Patient lacks awarneness and sleep-wake cycles, only displays reflective behaviour, classed as a coma after 6 hours.

Question 12

Brain death?

Answer 12

Patient lacks awareness, sleep-wake cyclesand brain-mediated reflexive behaviour, irreversible end of brain activity.

Question 13

Medically induced?

Answer 13

Used to protect brain from swelling after an injury, patient receives controlled dose of anesthetic causing lack of feeling or awareness.

Question 14

What is a neurophysical assessment?

Answer 14

used to examine cognitive consequences of brain damage or similar. Test includes ability areas such as memory attention, processing speed, reasoning, judgment, problem-solving, spatial and language functions.

Question 15

What is the Glascow coma scale?

Answer 15

Indicator of head injury severity, calculated on a patients eye opening verbal and best motor responses. Scors range from 3-15, less than 8 indicates coma, 9-12 indicates moderate head injury and above 12 mild head injury.

Question 16

What is a compound fracture?

Answer 16

Outside environment is in contact with the cranial cavity.

Question 17

What is a linear fracture?

Answer 17

Most common, traverse the full length of the skull from the outside to inside, usually fairly straight without bone displacement

Question 18

What is a depressed fracture?

Answer 18

Part of the skull bones press inward, present a high risk of increased pressure on the brain, or a haemorrhage to the brain that crushes delicate tissue.

Question 19

What is a diastatic fracture?

Answer 19

When the fracture line transverses one or more sutures of the skull causing a widening of the suture.

Question 20

What is a basilar fracture?

Answer 20

Linear fracture that occur on the floor of the cranial vault (skull base), which require more force so are rare.

Question 21

What is a laceration?

Answer 21

When the arachnoid mater and brain are damaged usually at the site of fracture.

Question 22

What artery is commonly damaged during extradural haemorrhage and why?

Answer 22

Middle meningeal artery, lies beneath the pterion where the skull is thinnest.

Question 23

How might patients with extraldural haemorrhage (EDH) present?

Answer 23

Lucid immediatley after a head injury only to become unconscious.

Question 24

What causes a subdural haemorrhage?

Answer 24

Acceleration of brain, brain lags behind skull in accleration, causing traction on bridging veins between brain and dura mater, which get torn. Blood slowly spreads in the subdural space and symptoms can take days to months to present and often there is damage to the underlying axons.

Question 25

What is a crainiotomy?

Answer 25

Surgical operation in which a bone flap is temporarily removed. Burr holes are drilled into the skull in several locations, these are then joined together to remove the flap and expose the dura.

Question 26

What are the four types of cerebral oedema?

Answer 26

Vasogenic, Cytotoxic, Osmotic, Interstitial.

Question 27

What is an internal herniation?

Answer 27

When there is a difference in pressure between two adjacent intracranial compartments (or an intracranial compartment and the spinal cord) causes the brain to be displaced into the compartment with lower pressure.

Question 28

What are the three sites herniation tends to occur?

Answer 28

Subfalcine - herniation of the cingulate nucleus under the flax cerebri.
Tentorial - herniation of the uncus of the temporal lobe through the tentorial notch.
Tonsillar - herniation of the cerebellar tonsils through the foramen magnum and onto the respiratory and cardiac centres of the medulla.

Question 29

What are post-traumatic seizures?

Answer 29

Seizures that result from a traumatic brain injury.

Question 30

What are thought to be the causes of immediate seizures?

Answer 30

The force of the injury stimulates brain tissue that has a low threshold for seizures when stimulated.

Question 31

What is thought to be the cause of early seizures?

Answer 31

Factors such as cerebral oedema, intracranial haemorrhage, cerebral contusion or laceration.

Question 32

What is thought to be the cause of late seizures?

Answer 32

Late seizures are thought to be the result of epileptogenesis, in which neural networks are restructured in a way that increases the likelihood that they will become excited, leading to seizures.

Question 33

What are the three types of partial seizures?

Answer 33

Simple partial seizure, complex partial seizure, partial seizure with secondary generalisation.

Question 34

What are simple partial seizures?

Answer 34

Seizure activity is limited to a focal area, there is no loss of consciousness. The origin of focal seizures leads to symptoms that depend on the area involved. The patient may experience weakness in the affected muscle.

Question 35

What are complex partial seizures?

Answer 35

Associated with impaired consicousness, the patient may be able to continuesimple motor behaviour.

Question 36

What are partial seizures with secondary generalisation?

Answer 36

Focal epilepsy may sometimes spread over the cerebral cortex, first on the side of the initial focus and then to the opposite hemisphere.

Question 37

what are generalised seizures and what are the two types?

Answer 37

Involves both hemispheres of the brain, thought to originate from midline structures like the thalamus. Absece seizures or tonic-colonic seizures.

Question 38

What are absence seizures?

Answer 38

‘Daydreaming’ woth th patient staring vacantly, sometime blinking or eye-rolling.

Question 39

What are tonic-colonic seizures?

Answer 39

3 stages: 1)patient becomes very rigid, all muscles undergo tonic, sustained contraction, there is no respiration. 2) Clonic phase during which the muscles go into strong, random conractions, may be accompanied by urinary/fecael incontinance 3) Coma, breathing becomes regular, neural activity is very high but blood oxygenation is poor..

Question 40

Why might a patient with a head injury be hyperventialted?

Answer 40

Makes them hypocapnic, causes vasoconstriction, blood vessels take up less space decreasing intracranial pressure, less fluid goes to the brain, so oedema does not worsen. The risk of sichemia is countered by 100% oxygen supply.