Unit 7 Chaper 41 Increased Intracranial Pressure, Craniotomy Flashcards
Why is ICP detrimental?
Within this space, there is li ttle room for any of the components to expand or increase in volume.
With ICP it can shift lobes of the brain and also cause a CSF leak
Cranium is closed cavity, therefore does not allow for swelling
What is the normal ICP? Can Increased ICP cause death?
A normal level of intracranial pressure (ICP) is 10 to 15 mm Hg. Periodic increases in pressure occur with straining during defecation, coughing, or sneezing but do not harm the uninjured brain. A sustained ICP of greater than 20 mm Hg is considered detrimental to the brain because neurons begin to die.
What is the tx for ICP
Mannitol
If the brain swells, is there an increase in intracranial pressure?
A. Yes
B. No
A.YES
If any of these increase in size, there is an increase in pressure:
* If the brain swells
* If the tissues around the brain swells
* If there is too much CSF
* If the blood vessels vasodilate
Complication of ICP
If the pressure is too high – continuously gets worse if not treated:
Which causes cerebral edema
If too high, the brain herniates down through the hole at bottom of
skull (Foramen Magnum) and leads to brain stem dysfunction
* Brain stem controls vital signs
* Changes in HR, BP, respiration, and temperature
- Can cause hypoxia of brain
- Hypoxia can lead to brain tissue death
- Brain tissue death leads to increase in “clean up” via increase in WBC to site which leads to
further intracranial processes (more blood flow) * CO2 accumulation causes vasodilation, which leads to further intracranial processes
Increased ICP is the leading cause of death from head trauma in patients who reach the hospital alive.
Increased ICP is the leading cause of death from head trauma in patients who reach the hospital alive.
What is the main goal for ICP?
prevent ICP
Can ICP cause brain death?
YES
If edema remains untreated, the brainstem may herniate downward through the foramen of Monro or laterally from a unilateral lesion within one cerebral hemisphere,causing irreversible brain damage and possibly death (from brain herniation syndromes discussed later)
Causes of ICP
Trauma (Ex: falls, or MVA) – swelling and bruising
- Blood flow comes along to make the bruise and to take away the blood cells
as bruises go away (think about a bruise on your arm or leg where you can see it.) - Disease – infection
- Increase in WBC to site of infection
- Inflammation
- Hemorrhagic stroke – extra blood in area
S/S OF ICP
Initially: Altered LOC, restlessness, HA, confusion
- Vomiting—projectile or recurrent
- Unequal pupils and abnormal response
- Blown pupils—late sign of herniation
- Posturing—decorticate, decerebrate, flaccid
Is cushings triad an early or late sign of ICP?
A. early
B. late
B. late
What are the s/s of Cushing’s triad?
CHANGE IN VITAL SIGNS:
Cushing’s Triad
* Bradycardia
* Rising systolic BP (severe HTN)
* Widened pulse pressure
* Slow respiratory rate
*Cheyne stroke respirations
Decerebrate
A person whose limbs all extend away from their head has decerebrate posturing.
Decorticate
A person whose elbows bend and fold their arms up toward their chest has decorticate posturing. A
Which abnormal posturing is more severe?
Decorticate or Decerebrate
Decorticate or Decerebrate posturing develops when ICP is increased.
Decerebrate posturing means there is damage to the brainstem, which is
serious