SF2: ICP and Brain Injury

Question 1

What are 5 causes of increased ICP?

Answer 1

• Expanding tumour or mass
• Increase in brain water content
• Increase in cerebral blood volume
• Vasodilatation
• Venous outflow obstruction

Question 2

What should normal ICP be?

Answer 2

<10mmHg is desired, but can fluctuate from 5-15mmHg

Question 3

What compensatory mechanisms are there to combat increased ICP?

Answer 3

• Displacement of CSF from the subarachnoid space of the brain to the spinal subarachnoid space
• CSF production within choroid plexus decreases
• CSF absorption increases
• Reduction in Cerebral blood volume
• Venous blood is shunted away
• Reduction in overall cerebral blood flow

Question 4

Describe the patho of ICP from injury to death.

Answer 4

• INJURY to brain → Tissue edema = ↑ ICP
• ↑ ICP → compression of ventricles → Compression of blood vessels = ↓ cerebral blood flow
• ↓ cerebral blood flow = ↓ O2 → death of brain cells → edema around necrotic tissue = ↑ ICP with compression of brainstem and respiratory center → accumulation of CO2
• Accumulation of CO2 → Vasodilation → ↑ ICP from ↑ blood volume = DEATH

Question 5

Management of ICP includes…

Answer 5

• Dx/Tx underlying cause
• Controlling intracranial HTN
• Supporting all body systems

Question 6

What are some complications of manually draining CSF?

Answer 6

• Infection: regular specimens taken to detect infection
• Over draining: never reposition the patient without switching off the drain first
• Blockage

Question 7

When is assessed with CSF samples?

Answer 7

• Color and clarity

Question 8

How does Mannito (Osmitrol) work?

Answer 8

• Shunts fluid away from the swelling into circulation

Question 9

Mannitol is contraindicated for pts with _____ disease.

Answer 9

• Renal

Question 10

Causes of PRIMARY brain injury include…

Answer 10

• Acceleration: the head is rotated, accelerated, decelerated and the brain is forced to follow the movement of the skull
• Penetrating Injury: the skull becomes broken up and the scalp lacerated
• Crush Injury: Where the head is caught between two unyielding surfaces

Question 11

What are some examples of secondary brain injury…

Answer 11

• Lack of oxygen to the brain
• Systemic Hypotension
• Bruising and swelling of the brain
• Haematoma formation
• Respiratory complications
• Sustained increased intracerebral pressure
• Electrolyte imbalances
• Infections

Question 12

Define epidural and subdural bleeds in relation to head injury.

Answer 12

• Epidural bleed is between skull and dura matter (above dura)
• Subdural bleed is between cerebrum and dura matter (below dura)

Question 13

What are some general s/s of aa basilar skull fracture?

Answer 13

• CSF/brain ottorrhea,
• bulging of tympanic membrane,
• Battles sign,
• hearing problems,
• vertigo,
• conjugate deviation of glance

Question 14

What is conjugate deviation of glance?

Answer 14

• a sustained shift in horizontal gaze toward 1 side, together with gaze failure to the other side

Question 15

What actions are taken for a pt presenting w/ head injury?

Answer 15

• Emergency management of head injury- observation, stabilization and preventing secondary damage.
• Ct Scan/MRI scan
• Cervical X Ray
• Surgery if indicated this could be immediately

Question 16

What is our nursing management for a stabilized pt with head injury?

Answer 16

• Get History – subjective/objective (may need to be from family member)
• Observation
• Airway
• Positioning of the patient
• Prevent extreme movement
• Limit noxious stimuli
• Prevent seizures
• Pain control- codeine phosphate
• Prevent Hyperthermia
• Avoid waking the patient
• Nutrition

Question 17

What are three main components of long-term care for a head injury pt?

Answer 17

• Psychological support for the patient
• Rehabilitation for physical deficits
• Family/career support