acute intracranial problems

Question 1

CSF circulation

Answer 1

• 4 ventricles

- subarachnoid space

Question 2

CSF function

Answer 2

cushioning for brain and spinal cord

Question 3

CSF formation

Answer 3

choroid plexus in the ventricles

Question 4

CSF absorption

Answer 4

arachnoid villi

Question 5

CSF resemblence

Answer 5

ultra filtrate of blood

Question 6

ICP

Answer 6

• hydrostatic force measured in the brain CSF compartment

- balance of brain tissue, blood, & CSF

Question 7

factors that influence ICP

Answer 7

• arterial and venous pressure
• intra abd and intra thoracic pressure
• posture
• temperature
• blood gases/CO2

Question 8

CBF (cerebral blood flow)

Answer 8

• amount of blood in mLs passing through 100g of brain tissue in 1 min
• 50mL/min/100g of brain tissue
• white matter: 25mL/min
• gray matter: 75mL/min

Question 9

factors that influence CBF

Answer 9

• decreased O2

- increased CO2, pH

Question 10

normal ICP

Answer 10

5-15 mmHg

Question 11

normal CPP

Answer 11

60-100 mmHg

Question 12

normal MAP

Answer 12

70-105 mmHg

-perfusion

Question 13

MAP calculation

Answer 13

[SBP + 2(DBP)] / 3

Question 14

CPP calculation

Answer 14

MAP-ICP

flow x resistance

Question 15

CPP

Answer 15

-pressure needed to ensure blood flow to the brain

-

Question 16

indications of monitoring ICP

Answer 16

• neurological insults
• patients with GCS of 8 or less
• abnormal CT or MRI

Question 17

methods of measuring ICP

Answer 17

• *ventriculostomy (also drains CSF)
• fiberoptic catheter (in brain tissue)
• subarachnoid bolt or screw

Question 18

increased ICP

Answer 18

• life threatening (above 20mmHG)
• diminishes CPP
• increased risks of brain ischemia and infarction
• poor prognosis

Question 19

causes of increased ICP

Answer 19

• mass lesion

- cerebral edema

Question 20

increased ICP compensation

Answer 20

• altered CSF absorption or production
• changes in intracranial volume
• brain tissue distention or compression

Question 21

LOC in increased ICP

Answer 21

• most sensible and reliable indicator of neurological status
• EEG

Question 22

VS in increased ICP

Answer 22

• increased temp
• Cushing’s Triad
• systolic HTN with widening pulse pressure
• bradycardia
• full and bounding pulse
• irregular respirations

Question 23

ocular s/s in increased ICP

Answer 23

• ipsilateral pupil dilation
• sluggish or no response to light
• inability to move the eye upward
• ptosis of the eyelid
• blurred vision
• diplopia
• changes in extra ocular eye mvmt
• papilledema

Question 24

motor function in increased ICP

Answer 24

• contralateral hemiparesis or hemiplegia
• painful stimuli: localize or w/d
• noxious stimuli: decorticate posturing and decerebrate posturing

Question 25

other s/s of increased ICP

Answer 25

- HA worse in the morning | - vomiting usually without nausea, sometimes projectile

Question 26

complications of increased ICP

Answer 26

- tentorial (central) herniation - uncal herniation - cingulate herniation

Question 27

tentorial herniation

Answer 27

separates the cerebellum and cerebrum

Question 28

cingulate herniation

Answer 28

between cerebral hemispheres

Question 29

mgmt of increased ICP

Answer 29

- surgery - drug tx - nutritional tx

Question 30

drug tx in increased ICP

Answer 30

- Mannitol (osmotic diuretics) - 0.9NS (hypertonic) - dexamethasone - pentobarbital - acetaminophen - phenytoin - propofol

Question 31

low Na in increased ICP

Answer 31

brain swelling

Question 32

Cheyne-Stokes

Answer 32

cycles of hyperventilation and apnea

Question 33

central neurogenic hyperventilation

Answer 33

sustained, regular rapid and deep breathing

Question 34

apneustic breathing

Answer 34

prolonged inspiratory phase or pauses alternating with expiratory pauses

Question 35

cluster breathing

Answer 35

clusters of breaths follow each other with irregular pauses between

Question 36

ataxic breathing

Answer 36

- completely irregular with some breaths deeps and some shallow - random, irregular pauses, slow rate