Child Abuse Injuries: Shaken Baby Syndrome 1/3

As a pediatric ER nurse, I would be remiss in not taking note that April is Child Abuse Prevention month. Sadly, this is part of my job as a pediatric ER nurse—to recognize and report child abuse injures.

A couple of years ago, I did a two part series on how we identify child abuse injuries. You can read Part I and Part II by following the links.

This week I thought I’d highlight one very specific injury—Shaken Baby Syndrome (SBS).

In the medical community, SBS goes by another name—abusive head trauma (AHT) and many things can fall under this designation. A child who is just shaken, a child that is shaken and then slammed into a surface, or a child who is beat about the head.

Fatal child abuse can occur from a single act (drowning, suffocating, shaking), repeated abuse (battered child syndrome), or failure to act (malnourishment or bathtub drowning.) Eighty percent of perpetrators are generally the biological parent(s) followed by mother’s paramour and babysitters.

SBS is caused when a person generally grabs an infant around their torso and shakes them violently in order to quiet their crying. We don’t know exactly how long it takes and no sane ethical review panel is going to allow infants to be shaken to unconsciousness to find out. What we know from people who have confessed is that it doesn’t take very long—likely twenty seconds or less—typically lasting five to ten seconds.

Imagine holding a ten to twenty pound baby with outstretched arms and sustaining that position. The shaking is violent and requires a lot of energy as well. 

What happens upon shaking is as follows:

1.      The brain strikes the inner surfaces of the skull, causing direct trauma to the brain itself. This is often referred to a coup/contra-coup injury. The brain is injured both ways as it is batted around within the skull.

2.      The axons, which are the long part of the nerve cell (you can view them like an electrical wire) can be broken or sheared. Whenever there is biological injury things swell (like your ankle when it is badly sprained.) This occurs to the brain as well. This is referred to as Diffuse Axonal Injury or DAI.

3.      The lack of oxygen during shaking causes further irreversible damage to the brain. This is referred to as Anoxic Brain Injury.

4.      Damaged nerve cells release chemical mediators which further damage cells.

5.      The end result is brain swelling, brain movement (herniation) and brain death.

There are other injuries that are classically associated with SBS but the diffuse axonal injury and subsequent brain swelling are generally what cause death.

Why is this different than brain injuries from a car accident? Why can’t kids recover?

Think of a car accident. It may entail one or two hits—a focal injury. A focal injury means just one area of the brain may be injured. Given time, the brain may rewire itself pretty amazingly in this age group and they tend to do better than those suffering from SBS.

Sadly, the whole brain is injured in SBS and therefore there is no healthy brain tissue to attempt recovery. Due to pressure and swelling within the skull, the brainstem is forced into the spinal column (herniation) which disrupts blood flow to it. This is the area that control heart rate and respiration.

Next post we’ll talk about other associated injuries. 

And please-- never, ever shake an infant. 

For help in dealing with a crying baby-- click here.