Unit 1: Increased Intracranial Pressure Flashcards
Monro-Kellie Doctrine
3 components (brain tissue, blood, and cerebrospinal fluid) occupy a rigid box, the skull -When one of these 3 increases, the other components must decrease to maintain equilibrium, preventing further injury to the brain through compression of the tissue within the fixed box (skull)
What 3 components occupy the skull?
- Brain tissue (80%)
- Blood (10%)
- Cerebrospinal fluid (CSF) (10%)
Intracranial Compliance
ability of the body to compensate by adjusting the levels of the components (brain tissue, blood, and CSF)
Brain Tissue
composed primarily of water
-makes up 80% of the intracranial components
Blood + Cerebrospinal fluid (CSF)
each make up 10% of the remaining contents within the cranium
Normal ICP
0-15
Herniation Syndromes
classified according to the region of tissue that is displaced
- brain shifts
- can occur with continued addition of volume
- S/S: “Cushings Triad”: increased SBP w/ widening pulse pressure, bradycardia, and irregular respirations
Cushings Triad
-Increased Systolic BP w/ widening pulse pressure
-Decreased HR (bradycardia)
-Irregular Respirations
>late sign of Increased ICP
>occurs late in the herniation process as the brainstem is compressed
Increased ICP Assessment Findings
- Increased confusion
- Progressive lethargy
- Sluggish pupils
- Motor Weakness
- Vomiting
- No change in vital signs
Herniation Assessment Fidnings
- Unresponsive (GCS <8); coma
- Unilateral or Bilateral pupillary dilation
- Contralateral (opposite side) Hemiparesis
- Flexor or Extensor posturing
- Positive Babinski reflex (toes flare out)
- Cushings Triad
Glasgow Coma Scale
-Best Eye Opening (1-4)
-Best Motor Response (1-6)
-Best Verbal Response (1-5)
>15 highest score
>3-8= coma
What is the most sensitive indicator of increased ICP?
decreased LOC
How to detect Increased ICP?
-neurological assessments
-elements of wakefulness
-arousal
-cranial nerves
-motor function
>establish an accurate baseline of functioning from which to judge deterioration
Management of Increased ICP
- Decreasing the volume of brain water, blood, or CSF in the intracranial space
- Emergency management: airway management and therapies to decrease intracranial contents (osmotic diuretics, hyperventilation)
- Vigilant monitoring (neurological status)
Management of Increased ICP: Vigilant monitoring
- To identify neurological deterioration that places a patient at risk for increased ICP and cerebral herniation syndrome
- Assess oxygenation, ventilation, and hemodynamic parameters to optimize therapy and prevent or mitigate brain injury
- Full systems assessment to identify signs of complications/ conditions that may negatively impact the patient w/ increased ICP, such as respiratory compromise
- Assess laboratory values (serum electrolytes, serum osmolality) to detect electrolyte imbalance and dehydration, which can lead to renal insufficiency or failure