Diabetic Ketoacidosis (DKA)

Too Much Sugar in the Blood for Too Long

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If you were a car and your fuel pump broke down while you had a full gas tank, you'd have the makings of diabetic ketoacidosis (DKA). To understand DKA--a very complicated condition--you have to understand how sugar works in the bloodstream. DKA is commonly--and incorrectly, in my opinion--referred to as diabetic coma.

Sugar and Insulin

Your brain works on one fuel source: sugar. Technically, it's a form of sugar called glucose.

This, mixed with oxygen, is burned by the brain to create energy. The rest of your body--with a couple of exceptions--can burn either glucose or fat to create energy (along with oxygen).

Since most of your body tissues can use either fuel source, they have to be able to accept either one. Your tissues can burn fat without any help, but glucose must be escorted into the cells on the backs of a hormone called insulin. Think of insulin as your fuel pump. The fuel, glucose, is in your bloodstream. The presence of insulin allows you to pump glucose into your cells where it can be burned for energy.

Your brain, since it only can burn glucose, doesn't need insulin. That's important as we see how DKA develops.

Clean or Dirty Fuel?

Glucose is a very clean fuel source. Your body can burn it without any bad side effects and it's all used. Fat, on the other hand, leaves behind contaminants known as ketones.

How those ketones are created is a complicated process through the liver. Ketones are acidic and as they build up, the bloodstream becomes more acidic.

Not Enough Insulin

One of the ways diabetes happens is through the loss of insulin production in the pancreas. Since insulin is the pump that moves glucose out of the bloodstream and into the cells, decreased insulin production leads to decreased glucose burning.

Decreased insulin happens slowly and many people don't even see it coming.

As insulin production decreases, the body begins to burn more fat and glucose builds up in the bloodstream. Along with the glucose, acid from ketones also builds up. Since the brain doesn't need insulin to burn glucose--and since glucose isn't being used anywhere else so it is in ample supply--the brain continues to burn glucose just fine in the first few days after insulin production decreases.

In order to expel the excess ketones and glucose in the bloodstream, the kidneys filter out extra urine. All the extra urine expels more fluid than usual, causing the body to become more thirsty and dehydrated. One of the most common complaints of new diabetics, or diabetics who don't yet know they're diabetic, is thirst. They're also craving sugar, because the body feels as if it isn't getting any.

Why the Brain Malfunctions

So, you might be thinking: if the brain only needs glucose and has more than it needs, what's the problem?

It's the acid.

You're right. The brain can burn glucose and has more than it needs since insulin isn't available to move it into other cells. However, the ketones building up in the bloodstream are causing the blood to get more and more acidic.

Your brain is picky. It has to be warm enough and not too hot. It has to have an environment that's not too acidic and not too alkaloid. As ketones build up and the bloodstream becomes more acidic, the brain starts to malfunction. It becomes confused and tired.

How Long Does It Take

Diabetic ketoacidosis takes a long time to occur. The patient or the patient's family might not realize it because the most significant sign, confusion, might seem to be a sudden development. But it takes quite a while for the buildup of ketones to make the bloodstream acidic enough to affect the brain.

On the other hand, the other symptoms of hyperglycemia, increased urine output and thirst, happen much quicker. If patients or family members are paying careful attention to the signs their bodies are showing them, DKA might be avoided or at least be more readily identified if it happens.

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