Cerebral Edema

Leslie Asks:

My character has been in a car accident and sustained head damage (swelling to the brain)— is there a medical term for that? Also, the swelling becomes so bad the doctors have to remove part of her skull— is there a name for that? How long does that swelling usually take before it goes down so they can replace the skull? Does the character regain consciousness? I have her in an induced coma which I want her in for a while.

Jordyn Says:

Upon further clarification of this question from the author, she says there is not a significant description of the motor vehicle collision in the manuscript and the scene is being told from the POV of a nurse.

The brain swelling is called cerebral edema. Usually, if it’s a significant car accident then there is usually bleeding as well. This is why I ask about the car accident. It should be pretty serious.

A nurse will use language that a family can understand. So, I might actually avoid a lot of medical terminology when speaking to the family unless I also clarify what the words mean.

I might say something like, “Your mother (or whatever relation) has a lot of swelling in her brain as a result of the car accident. We call this cerebral edema.”

A craniectomy is where they remove a portion of the skull.

Peak brain swelling is generally 48-72 from the time of injury and diminishes from there. Induced coma is a reasonable medical scenario here.

Whether or not this patient regains consciousness is up to you as the writer. Statically, the odds are pretty low for her to be the same person she was before. If she does wake up, she’ll have extensive rehab needs for sure– but you could write it either way.

Best of luck with your story!

The brain is our most complex organ and perhaps the most difficult to help heal. The biggest challenge is its protective covering: the skull. Management of acute traumatic brain injury, or TBI, typically involves manipulating the three components within the skull: the brain, the blood, and the cerebrospinal fluid (CSF).

What is the purpose of each of these components? The brain is the body’s supercomputer. The blood delivers oxygen and nutrients to feed the cells or neurons. The CSF nourishes the brain, helps remove waste products, and keeps the brain buoyant.

What happens when something is significantly injured? It swells. Think about a time you saw someone with a really bad sprained ankle. What happened? It blew up like a balloon. The same thing happens to the brain with a traumatic injury. It swells.

Unlike an ankle, brain swelling is inhibited by the skull but the pressure inside the head can continue to rise if swelling is unchecked. Too much pressure inside the skull (it can’t move) and blood flow diminishes, thereby starving cells of oxygen, which then swell more.

We can measure the pressure inside your skull, or intracranial pressure (ICP), by placing a sensor into a ventricle (a ventriculostomy). A normal ICP is 7-15mmHg. Cerebral edema can be insidious as swelling peaks 48-72 hours post injury. A patient can initially present following commands. Then in 2-3 days, develop cerebral edema to the point of herniation (which means brain contents shifting) and die.

What happens when a patient develops significant cerebral edema and ICP pressures skyrocket?

First bad thing: Blood flow is reduced. The brain is very sensitive to blood flow and greedy for oxygen. If there is diminished blood flow, neurons (brain cells) begin to die. If there is no blood flow, the brain will die. You may have heard the term brain death. This is determined by several factors but the definitive one is by taking the patient to radiology and doing a brain flow study. Roughly, a dye is injected into the blood and x-rays are taken. If there is no blood flow, the patient is declared brain dead.

Second bad thing: Brain contents shift into areas where they’re not supposed to be. This is called herniation. When neurons are compressed, they don’t function properly and will begin to die as well. When brain cells die, machines and medications have to take over their function to keep the patient alive.

Unfortunately, if brain death has occurred, the medical team will start discussing withdrawal of care with the family.

***Content reposted from January, 12, 2011.***