TBI Flashcards
Add pleural effusion
Normal ICP for a supine Pt.
10-15 mmHg
What is the ceiling ICP in many ICUs
20mmHg
What happens if the ICP equals MAP
Perfusion ceases and brain dies
What is cerebral perfusion pressure
Indicates adequate perfusion to brain, which can be measured directly
Formula for cerebral perfusion pressure (CPP)
MAP-ICP
What is a normal CPP value
65-80
What GCS indicates mild TBI
14-15
What GCS indicates moderate TBI
9-13
What GCS indicates severe TBI
Equal or less than 8
Why do patients with TBI get blown
Optic nerve is paralyzed
What is mydriasis
A blown pupil
What is decorticate posture
Abnormal flexion
What is decerebrate
Abnormal Extension
What are symptoms of impending or active cerebral herniation
Decorticate or decerebrate
Pupillary asymmetry
Bilateral or unilateral fixed and dilated pupils
Cushing triad: hypertensio, Brady and irregular RR
What causes brain herniation
Increased cerebral pressure
What is the danger of brain herniation
ICP squeezes brain out of its restraints (skull)
What is a midline shift (brain)
BBB is compressed (mass effect)
Compresses the ventricle and pushes midline over
Examples of primary brain injury
Direct impact
Rapid acceleration and deceleration
Penetrating injury
Blast wave
What are examples of secondary brain injury
Cerebral edema
Inflammation
Electrolytes imbalance
Death of neurons
What causes secondary brain injury
Subtle changes in the brain and nervous system that follow primary injury
Time course of cerebral edema
Accumulation is gradual
Peaks in a few days
Contributes to intracranial hypertension
What is the most common cause of cerebral edema
Vasogenic edema
What is the goal for treatment of TBI
Treat primary brain injury
Stall or minimize secondary brain injury
What is the danger of cerebral edema
At the time of initial injury, a catecholamine surge increases HR and BP potentially damaging brain’s architecture
What are the four interventions for treating ICP
Hyperosmolar 4 solution
External ventricular drains
Evacuation of blood clot
Craniectomy
What are hyperosmolar solutions
Mannitol (IV)
Hypertonic saline 3% (IV)
How does hyperosmolar IV work
Pulls fluid back into vessels
Danger of intubating a patient with ICP
Intubation can increase it
Gentle intubation technique
Comatose patients can still generate reflex response (stim of supraglottic larynx)
What are respiratory therapist role in avoiding secondary injury of ICP
Prevent 2nd injury
Gentle intubation
Mgt vent
Mgt O2
Hazards when hyperventilating patients with ICP
PaCO2 <25mmHg can decrease ICP, but can reduce blood delivery
Should hyperventilation be used for ICP
Can be, but should be avoided
25-30mmHg
When is hyperventilation with ICP dangerous
24-48 hrs
Tolerance increases after
Means to relieve ICP
Extraventricular drains
Evacuation of blood clot
Crainectomy
How doe craniectomy work
Open skull
Remove clot
Give brain room to expand
Return
Difference between crainectomy vs Crainotomy
Otomy is returned
Ectomy is held
What does IICP stand for
Increased intracranial pressure
