ICP Flashcards
ICP measurement
> 15 mmHg
ICP measurement acc. to Brunner
10-20 mmHg
Causes of ICP
Head injury
stroke
inflammatory lesions
brain tumor
Surgical complications
Components of cranium (brain substance)
CSF and blood/blood vessels
An increase in any of the components causes a change in the volume of the other
MONRO-KELLIE hypothesis
Any alteration of brain substances or structure will cause
increase ICP
Compensatory mechanisms
Increased CSF absorption
Blood shunting
Decreased CSF production
Decompensatory mechanisms
Decreased cerebral perfusion
Decreased PO2 = brain hypoxia
Cerebral Edema
Brain herniation
Vasomotor reflexes are stimulated (Decreased cerebral bld flow)
slow bounding pulses
Increased concentration of CO2 (Decreased cerebral bld flow)
Vasodilation—Increased flow—Increased ICP
Abn accumulation of fluid in intracellular space, extracellular space or both
Cerebral edema
Results from an excessive increase in ICP when the pressure builds up and the brain tissue presses down the brain stem
Herniation
Cerebral response to Increase ICP
Cushing’s response
Altered LOC
Headache/Migraine
Cushing’s response
- Vasomotor center triggers rise in BP to increase ICP
- Sympathetic response is increased BP but the heart rate is SLOW
- Slow Respiration
Early Manifestation
*Changes in LOC (earliest)
*Pupillary changes - fixed, slowed response
*Headache
*Vomiting
Later manifestation
- cushing reflex (systolic hypertension, bradycardia, wide pulse pressure)
- Bradypnea
- Hyperthermia
- Abn posturing
Nursing intervention to Increased ICP
- Elevate head of bed 15-30 deg
- assist in adm 100% O2 or controlled hypervent
- Adm prescribed meds
- reduce environmental stimuli
- Avoid act. that increase ICP
- Keep head in neutral position
- Monitor for secondary complications
Elevate the head of the bed 15-30 degrees-
to promote venous drainage
assists in administering 100% oxygen or controlled hyperventilation-
to reduce the CO2 blood levels—constricts blood vessels—-reduces edema
Prescribed meds for ICP
Mannitol
Corticosteroid
Anticonvulsant