Page 166 - Critical Care Notes

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NEURO

Management
■ Brain herniation is a medical emergency.
■ Refer to ICP section.
■ Insert catheter to remove CSF.
■ Administer corticosteroids (dexamethasone).
■ Administer mannitol.
■ Intubate and put patient on mechanical ventilation to reduce CO 2 levels.
■ Remove blood or blood clots if causing herniation.
■ Remove part of the skull.
Spinal Cord Injury (SCI)
SCI may be classified as complete (loss of conscious sensory and motor func-
tion below the level of SCI as a result of transection of the spinal cord) or incom-
plete (preservation of some sensory and motor function below the level of SCI
as a result of partial spinal cord transection). The most common sites of SCI are
C4–C7, T12, and L1.
Causes of SCI include:
■ Motor vehicle accidents
■ Diving accidents
■ Falls
■ Blunt force trauma
■ Penetrating force trauma
■ Spinal abscesses and tumors, especially lymphoma and multiple myeloma
Pathophysiology
■ ↓ blood flow to gray matter of spinal cord with 8-hr delay of ↓ blood flow to
white matter → thrombi form furthering ↓ blood flow to spinal cord.
■ ↑ interstitial pressure related to edema →↓ blood flow to spinal cord.
■ Inflammatory process → edema of injured area →↓ blood flow to spinal
cord. Edema moves up and down the spinal cord rather than laterally.
■ Release of norepinephrine, histamine, and prostaglandins → vasoconstric-
tion →↓ cellular perfusion.
■ ↑ extracellular fluid concentrations of Na + and K + →↑ osmotic pressure in
area of injury → edema.
■ Ischemia, hypoxia, and edema → tissue necrosis and cell membrane dam-
age → destruction of myelin and axons → neuronal death.

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