Cerebral edema and its management
Cerebral edema is the increase in the content of brain water, that is when the brain water content rises above the normal levels of 8/10ths. This disorder is usually a result of and response to a primary brain insult. Cerebral edemas are observed in a large number of cases related to brain injuries, including but not limited to toxic–metabolic derangements, inflammatory diseases, primary and metastatic neoplasms, ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage or traumatic brain injury.
Osmotic therapy: The most effective and quick method of reducing brain bulk and tissue water is Osmotherapy. Osmotic therapy is designed to decrease blood viscosity by sucking the water and fluids out of the brain using an osmotic gradient. These changes trigger a reduction in the ICP (intracranial pressure) and result in an increase of the CBF (cerebral blood flow, i.e., blood to the brain). The most-employed and popular osmotic agent are Mannitol, while another popular one is Glycerol. The latter is a beneficial agent which is employed to patients orally as a 2.5% saline solution in the form of 50g in 500 ml in the daily IV or amounts of 30 ml and given every 4-6 hours.
Diuretics: As is with osmotic therapy, the osmotic effect can be extended and lengthened using loop diuretics (Furosemide) after the infusion of an osmotic agent. The loop diuretics can be used as aides.
Corticosteroids: Corticosteroids are responsible for lowering the ICP (intracranial pressure) chiefly in the vasogenic edema, especially because of its positive effects and consequences on the blood vessel. The edema around the brain tumors, especially the metastatic brain tumors, responds excellently if the treatment is done with a high dosage of Dexamethasone.
Hyperventilation: Raised ICP can be reduced in a helpful way using controlled hyperventilation. The cerebral vascular system is susceptible to changes in arterial pCO2, especially when they waver from their usual levels of 40 mm Hg. While the ICP falls as soon as the commencement of hyperventilation happens, the extracellular fluid and the CSF have safeguarding mechanisms which quickly restore the pH level to normal, and the effects of which could last for a long time.
Surgical treatment: Sometimes, surgical treatment is suggested for life-threatening shifts in the brain and large hemispherical infarcts with edema. Temporary craniectomy or ventriculostomy could prevent the worsening and could even end up being a lifesaver. In severe cases of hydrocephalus, the VP shunt proves to be a boon.