|Is it the glucose or the insulin??|
When I teach clinical seminars, I always, always talk about fluid and electrolytes. One of my favorite things to talk about is potassium. In particular, how we treat hypo and hyperkalemia. In the next few blog posts, I'm going to map out some of the most common treatments for hyperkalemia - starting with glucose and insulin.
One thing you need to understand about potassium is that you have WAY MORE potassium INSIDE (145 mEq/L) the cell than you do OUTSIDE (3.5-5 mEq/L) the cell. So, any time you damage the cell wall or change the pH of the blood (will discuss that in a future blog post), the potassium INSIDE the cell will leak out into the extracellular space (blood vessel).
Knowing that hyperkalemia can wreak havoc on the heart and other muscles, it's important to get the potassium back into the cell where it belongs!!!
TREATING HYPERKALEMIA WITH GLUCOSE AND INSULIN
A treatment for hyperkalemia is to give the patient a injection of insulin followed by dextrose. When nurses are asked “who” is the hero, many do not know.
To answer this question, you need to understand how “things” enter in and out of the cell.
We all know that insulin acts as a key to unlock the door of the cell to allow glucose to enter. But glucose isn’t the only thing that enters the cell when insulin unlocks the door.
Did you figure it out?
If you answered insulin, you are right. Insulin is the hero in your hyperkalemic patient because when insulin unlocks the door, potassium slips into the cell along with glucose. The ONLY reason that you give the dextrose is to prevent the patient from becoming hypoglycemic. Actually, if your patient is hyperglycemic, you may not need to give any dextrose at all – depending on the situation.
A bit of caution – giving a hyperkalemic patient insulin is a temporary fix. If you haven’t fixed the problem (renal failure, acute trauma, etc) the potassium can leave the cell and go right back into the extracellular space!
Knowledge is power – ignorance is not a defense.
Thanks so much for reading and for choosing to become a nurse. I’m cheering for your success!