Hyperglycemia Hyperosmolar Nonketotic Coma

Daytonite, BSN, RN · Oct 31, 2008

ketones are not normally present in the urine. if ketones are present in the urine it means there is massive fatty acid catabolism going on. how does this happen in someone who is diabetic? when a patient is diabetic, their pancreas is not putting out enough insulin (type i) or they are putting out defective insulin that doesn't do its job (type ii) so that the carbohydrates that the person has ingested can't get into the cells where is can be processed for energy that the body can utilize for its many functions. what happens is that their body begins to draw upon the stores of fat to get that energy that they need to live. as their body is burning up that fat, ketones are produced as an end product. the way the body rids itself of these ketones is to primarily dump them via the kidneys, but they can also exit through the lungs. so, if the urine is analyzed it will show the presence of ketones, a sign that massive fat metabolism is occurring in the person's body over any glucose metabolism. these patients can develop dka (diabetic ketoacidosis). it happens almost exclusively in type i diabetics because their pancreas is gradually losing the ability to produce insulin.

type ii diabetics are producing substandard insulin that fails to do its job correctly, thus, the term insulin resistance. their pancreas works overtime putting out 2, 3, 4 times the amount of insulin molecules required of a normal person to get their job done. think of type ii diabetic insulin molescules as being slackers where it takes a bunch of them to do what one of yours does. their insulin is very inefficient. over time some have their pancreas eventually peter out from exhaustion if they do not help it rest by easing up on ingesting high carbohydrate foods all the time and some of them do eventually end up going on insulin replacement way down the road of the course of their disease. when type ii diabetics are hit with a situation that is going to put a sudden and acute strain on their insulin production such as a massive infection, traumatic injury, or anything that is going to interfere in some way with their body's processing of glucose, they are set up for hhnc (or, hhns-hyperosmolar nonketotic diabetic syndrome). what happens is that their blood sugars are elevating, but there is still enough insulin production going on so that fatty acid metabolism doesn't kick in as a failsafe mechanism here. so, no ketones are going to appear in the urine because this person's pancreas is still able to make insulin that can carry out glucose metabolism. as inefficient as it might be, the insulin is still achieving results for this person although there is so much glucose hitting on their system it is willing around to be let into the cells so it can be processed--and waiting--and waiting--and building up. think about it as standing in a l-o-n-g line to get a hamburger and there are 3 workers at the counter and only one of them seems to be taking orders and is working about as slow as molasses. that's the picture.

now, here is where the two are the same. because glucose is building up in the blood, the blood sugar continues to rise and hyperglycemia occurs. the kidneys want to get rid of this glucose, so it starts to dump it. the renal threshold for glucose is 160 to 180 mg/dl. that is when the kidneys start filtering glucose out of the blood. it needs water to do it and so the poor patient ends up getting dehydrated.

the primary feature of both dka and hhnc (or hhns) is dehydration. it is the dehydration that leads to most of the symptoms that the patient has. the pathophysiology of these two are:

with hhnc (or hhns) glucose levels continue to rise as a result of an infection, drugs such as glucocorticoids that interfere with glucose tolerance or increased fluid losses from diuretics so that the metabolism falls behind in processing the glucose and the blood sugar elevates. once the glucose levels are elevated, the body starts to compensate by attempting to dump sugar through the kidneys-->resulting in dehydration
with dka there just isn't enough insulin to process the glucose in the body. once the glucose levels are elevated, the body starts to compensate by attempting to dump sugar through the kidneys-->resulting in dehydration

hope i explained that clearly enough. it is very clear in my mind, but i can't see inside yours!

http://www.merck.com/mmpe/sec12/ch158/ch158d.html - nonketotic hyperosmolar syndrome (nkhs)
http://www.merck.com/mmpe/sec12/ch158/ch158c.html - diabetic ketoacidosis (dka)

by the way, one of the ways diet programs check to see if their clients are losing weight is to do urine dip sticks to see if they are throwing off ketones. it indicates they are burning fat and taking in less carbohydrates. some people on diet programs who are burning huge amounts of fat also get that fruity ketone breath since that is another way the body tries to dump the ketones that are building up in the blood - through the lungs. once you've smelled that "fruity" breath, you never forget what it smells like.