Acute Intracranial Pressure Flashcards
What is normal ICP and when to treat?
5-15mmHg above 20 is considered abnormal and must be treated.
Where does fluid go when there is a change in CSF volume?
Subarachnoid space
What happens to ICP when there is a change in brain tissue volume
Distention into the dura or compression of brain tissue
what happens when there is a change intracranial blood volume? 4
Collapse of cerebral veins, collapse of dural sinuses, cerebral vasoconstriction or dilation, changes in venous outflow.
normal cerebral blood flow
50ml/min/100g of brain tissue
Autoregulation
the autonomic adjustment made to the cerebral blood vessels by the brain. The brain regulates its own flow in response to metabolic needs.
stages of ICP and one thing about each
- Body compensates-feeling of doom
- Decreasing compensation- risk for secondary injury
- Failing compensation-Manifestations of ICP (Cushings triad) This is emergent.
- Herniation-pressure is placed on brainstem-death.
Cerebral Perfusion Pressure math
CPP=MAP(mean arterial pressure) -ICP
Normal Cerebral Perfusion Pressure
60 or 70mmHg-100mmHg
When is Cerebral perfusion pressure associated with tissue ischemia? When is it incompatible with life?
50mmHg
30mmHg
Damage of brain tissue can cause 5 and they all cause?
Hypercapnia, Acidosis, Impaired auto-regulation,HTN, brain herniation and they all cause edema.
Vasogenic and one thing to remember
Type of cerebral edema caused by large molecules leaking into interstitial space.(Tumors, Toxins, Abscesses) *BBB is weakened.
Cytotoxic and one thing to remember
Type of cerebral edema caused by disruption in the integrity of cell membrane causes fluid to shift into cells. causing tissue hypoxia. (Trauma, lesions) *BBB is still intact.
Interstital Cerebral edema
Build up of fluid in ventricles AKA hydrocephalus caused by obstruction of flow.
What is the MOST sensitive and reliable indicator of neurological status?
Change in LOC
When ICP increases people vomit what is different about this?
No nausea beforehand
Ptosis
Drooping up upper eyelid
Ocular signs of ICP 6
unilateral pupil dilation, sluggish response to light, inability to move eye up, eyelid ptosis, papilledema, positive oculo-cephalic reflex
what do pinpoint pupils mean?
Pons damage or drugs
Decorticate positioning and what does it mean?
flexed and in (don’t forget about legs) and it means that there are problems with cervical spinal tract or cerebral hemisphere
Decerebrate positioning and what does it mean?
Extensor problems within midbrain or PONS
things the Glasgow coma scale assesses and when is it a problem
Eye opening, verbal response, Motor response. less than 8.
Cushings triad
Increase in systolic BP, decrease in pulse, decreased respirations.
apneustic breathing related to… and what does it look like?
Related to pons Prolonged inspiratory phase or pauses alternating with expiratory incompletion
Drugs for ICP 9
Mannitol, hypertonic saline, corticosteroids, H2 receptor antagonists, Anti seizure meds, antipyretics, Sedatives, analgesics, barbiturates.
What does mannitol do?
Osmotic diuretic from ISF to ECF
Why use H2 receptor antagonists?
prevent GI bleeds and ulcers
Why use sedatives, analgesics, barbiturates?
Paralyze so we can intubate
Patient position for ICP
HOB 30 head in neutral, midline position
Where do you want systolic BP to be?
100-160mmHg
Suction time? Why
Less than 10-15 seconds to prevent cough
Why give laxatives?
avoid straining.
What is a brain abscess?
Build up of puss from local or systemic infection
Nursing measures to treat brain abscess
similar to meningitis and IICP
Primary bacteria associated with Abscess?
Staph and strep
S/S of meningitis 4 you don’t know
Nuchal rigidity, photophobia, positive kernigs or brudzinski sign.
What is Brudzinski’s sign?
patient neck is flexed by the primary and patient will flex their hips and knees.
what is kernigs sign
the primary is unable to extend the patients leg at the knee when the thigh is flexed due to stiffness of the hamstrings.
Neisseria Meningitis common with? S/S
College students, Cough, HA, Sore throat, upper respitor symptoms, mid stage-flu like symptoms, and petechial skin rash, purpura
Bacterial meningitis differences 5
Turbid, purulent, higher protein levels, glucose is decreased, neutrophils
Why manage a fever with meningitis? 5
Fever increases cerebral edema, IICP, seizures, and metabolic rate, can lead to neuro damage
Viruses that cause meningitis? 4 and most spread by
Enterovirus, arbovirus, herpes, HIV contact with respiratory secretions.
What is encephalitis? caused by? 6
Acute inflammation of the brain. Vectors, measles, mumps, Chicken pox, HSV, cytomegalovirus
What to remember about s/s for encephalitis
Any CNS abnormality can occur.
hemiparesis
Weakening on one side of the body
Treatment for encephalitis
Care that you would give everyone! atelectasis, skin breakdown, DVT, fluids, nutrition, constipation
MAP normal and equation
70-150 and SBP+2DBP/3
