Head Trauma

Question 1

Equation for intra-cranial volume

Answer 1

Water/brain+cerebral blood volume+CSF

Question 2

Monroe-Kellie Hypothesis

Answer 2

Under normal physiological conditions the volume of all 3 components in the vault remains in a constant relationship

H2O/ brain tissue = 80%
Cerebral blood volume=10%
CSF=10%

As the volume of one increases there is a corresponding decrease in the others to prevent increased ICP

Venous blood is displaced into the scalp
CSF is displaced into the subarachnoid space and production is decreased

Question 3

Equation for cerebral perfusion pressure

Answer 3

CPP=MAP-ICP

Question 4

Cerebral Blood Flow

Answer 4

Maintained at a relatively constant level over a wide range of CPP (50-100) therefore mild BP fluctuations will not impact CBF

Chronically hypertensive patients have a higher threshold and shift to the right on a graph

Question 5

Intracranial compliance

Answer 5

The interrelationship between the change in volume of intracranial components

High compliance -good
Increased ICP occurs when compensation is exhausted and compliance worsens
Mild increases in volume may resulting in dramatic increases in pressure and without intervention compliance fails and leads to herniation

Question 6

Herniation

Answer 6

Displacement of brain tissue, CSP, and blood vessels outside the their compartments

Question 7

Supratentorial herniations

Answer 7

Within the skull

Subfalcine
Uncal
Transtentorial

Question 8

External herniation

Answer 8

Between skull plates

Question 9

Infratentorial herniation

Answer 9

Through the foramen magnum

Tonsillar herniation

Question 10

Causes of increased ICP

Answer 10

Increased brain tissue/H2O
Cerebral edema
Brain tumor or other lesion

Cerebral blood volume
Loss of autoregulation due to
trauma, stroke
Decreased venous outflow
Sagittal sinus thrombosis
Increased intra-abdominal pressure
Positional- head
Hematoma

CSF
Hydrocephalus

Question 11

Assessment findings in worsening compliance

Answer 11

Decreased LOC
Decreased motor response
Decreased or unequal pupillary response
No change in vital signs

Question 12

Assessment findings after herniation

Answer 12

Unarousable
No motor response
No pupillary response
Vital signs Cushing Triad: Increased
blood pressure, bradycardia,
abnormal respiratory patterns

Question 13

Equation for cerebral perfusions pressure

Answer 13

CPP=MAP-ICP

Goal is to increase MAP and decrease ICP

Question 14

Ways to decrease ICP

Answer 14

Decrease H2O on the brain with isotonic IVF, limit free water, or give osmotic solutions like mannitol

Question 15

What to keep in mind with giving mannitol

Answer 15

With prolonged administration it may increase cerebral edema and ICP instead of lowering

Maintain euvolemia

Question 16

What to keep in mind with isotonic IVF

Answer 16

Included hypertonic saline solutions such as 2%, 3%, and 23% saline

Establish a Na goal of 140-150

Check Na q4-6

Avoid large shifts in Na in either direction

Question 17

Ways to decrease metabolic demand of the brain

Answer 17

Maintain normothermia

Seizure prevention

Treat agitation

Anesthesia (barbiturate therapy or propofol)

Treat paroxysmal dysautonomia (storming) with Bromocriptine, propranolol, or narcotics

Question 18

How to keep excess blood off the brain to maintain CPP

Answer 18

Hyperventilation therapy- CO2 dilates vessels so decrease CO2

Promotes venous outflow
HOB positioning
Avoid an increase intrathroacic
pressure
Avoid trendelenburg

Question 19

How to drain off excess CSF to increase CPP

Answer 19

Place an EVD

Question 20

Surgical methods for decreasing ICP

Answer 20

Decompressive hemicraniotomy

Question 21

Traumatic brain injury

Answer 21

An alteration in brain function or pathology caused by an external force

Question 22

Primary brain injuries

Answer 22

Occur at the time of trauma

Question 23

Secondary brain injury

Answer 23

Occurs immediately after the trauma and produces effects over the next several hours or days

Question 24

Moderate to severe TBI possible physical findingins

Answer 24

Raccoons eyes
Battle sign
Otorrhea
Rhinorrhea
Proptosis
Periorbital edema
GSW entrance and exit wounds

Question 25

Interventions for mild TBIs

Answer 25

Symptom management for headaches, vestibular disturbances, nausea and vomiting, and visual disturbances May be complicated by post concussion syndrome

Question 26

Post concussion syndrome

Answer 26

May last weeks to 3 months Symptoms may include headaches, nausea and vomiting, personality changes, visual disturbances, vestibular issues, irritability, anxiety, memory loss, depression, or cognitive disturbances

Question 27

Risks of moderate to severe TBIs

Answer 27

Cerebral edema Hydrocephalus Hypo ventilation Seizures Loss of airway protection Aspiration Loss of auto regulation Glucose abnormalities Loss of temp regulation

Question 28

Diffuse axonal injury

Answer 28

Characterized by extensive generalized damage to the white matter of the brain Produced in lateral motions of the head Straining of tentorium and falx during high speed acceleration/deceleration 90% remain in a persistent vegetative state

Question 29

Acute subdural hematoma

Answer 29

Immediately after injury to 72 hours after

Question 30

Subacute subdural hematoma

Answer 30

72hours- 2 weeks

Question 31

Chronic subdural hematoma

Answer 31

Last over 2 weeks

Question 32

Medical management of subdural hematoma

Answer 32

Observe and watch for reabsorption Surgical evacuation

Question 33

Epidural hematoma

Answer 33

Arterial Requires surgery Classic shows as: LOC- lucid- LOC

Question 34

Traumatic sub arachnoid hemorrhage

Answer 34

Most common kind of SAH History is key to determining if aneurysmal or traumatic

Question 35

Penetrating head injuries

Answer 35

Manage ICP Usually require surgery Life saving measures such as craniectomy may not improve quality of life