help! Besides insulin, why is potassium given to lower blood glucose?

  1. Hi,

    I've been stuck on this question all day after my instructor got our brains churning during clinical this morning.

    He said that besides insulin, potassium is also sometimes given to lower serum glucose and my questions are: why is it given and how does it work to lower bg?

    The only relationship I know that potassium has to bg-related things is insulin being used to temporarily treat hyperkalemia but other than that I have no clue.

    If you have any thoughts/knowledge/input it would be greatly appreciated!
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    Joined: Feb '05; Posts: 67; Likes: 3


  3. by   cursenurse
    your question got me interested, so i did a google search. i found a pediatric hospital website that talked about potassium stimulating the beta cells of the pancreas to secrete insulin, so in that way, potassium could lower blood glucose.
  4. by   EricJRN
    The potassium is not actually used to fix the blood sugar per se. When a patient's blood sugar is extremely high, the patient develops diabetic ketoacidosis, or DKA. When a patient's sugar levels get that high, one of the symptoms is diureses - basically, the patient pees a LOT. When they lose this water, their levels of electrolytes like potassium drop quite a bit, giving them a low total body potassium level. And we know that low pH/acidosis means lots of hydrogen ions floating around in the system, and the hydrogen pushes its way into the patient's cells, pushing potassium OUT of the patient's cells into the bloodstream.

    So now even though you have a low total body potassium level from diuresis, all of the potassium is in the bloodstream, so a potassium blood test may read high. So you give insulin to this patient with a low total body potassium and what happens? The insulin corrects the acidosis, the hydrogen ions bail out of the cells, and potassium re-enters the cells, leaving no potassium in the bloodstream (hypokalemia). Hypokalemia causes all kinds of problems, including cardiac/EKG issues.

    Hope this helps.
  5. by   schwalmys8862
    basically i head that potassium helps push the glucose out of the cells but am not sure how. That last post was a little lengthy and hard to understand. Can anyone explain it a little easier?
    Last edit by schwalmys8862 on Feb 10, '06
  6. by   daisywill
    Hi. I might be too late but I just saw this post. Potassium is used in rapid situations to push glucose IN the cells. This produces a decrease in SERUM potassium. Thats why kayxelate is used to push glucose into the cells. Hope I helped.
  7. by   EricJRN
    Give me one more chance.

    Original question: 'How does potassium work to lower blood glucose?'

    Answer: It doesn't. Potassium corrects a low potassium level seen in DKA. These patients start out low in K due to excessive peeing and the K can get worse due to cellular electrolyte shifts during insulin treatment.

    Sometimes potassium is given before insulin to avoid a potassium crash, but it's the insulin that actually goes to work on the high sugar level.

    Potassium and kayexalate do opposite things and would not be given to the same patient for the same reason.
  8. by   beannie
    Eric, lol your first explanation was clearer to me. Thank you, for both bits of good clinical information.
  9. by   texanrebel
    Thank you! That is the best response I have encounter thus far. I understand it too! Thanks again! You are why I love this site. Every time I study for a test and run into a brick wall, I come here and I am "unconfused" by someone intelligent like yourself.
  10. by   hippal01
    while the opposite of the question, i have seen insulin giving to successfully lower high potassium very quickly:
    15 units of regular insulin with 50 ml d50 to keep from lowering the blood sugar too much.
    see vanden hoek, tl; morrison, lj, shuster, m, donnino, m, sinz, e, lavonas, ej, jeejeebhoy, fm, gabrielli, a (2010-11-02). "part 12: cardiac arrest in special situations: 2010 american heart association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care.". circulation 122 (18 suppl 3): s829-61. [color=#0645ad]doi:[color=#3366bb]10.1161/circulationaha.110.971069
    alh/critical care rn
  11. by   classicdame
    thanks for the reference, hippal01. Insulin pulls out glucose to transport it to cells where it can be used for energy. Insulin also pulls out K. Some of it gets stored but MOST is lost to diuresis, as this article states. This is why we watch K levels when pt is on insulin drip.

    BTW, I ask my students if K is compatible with insulin in IV. The answer is yes, but that is misleading. The rate of insulin is MUCH LOWER than therapeutic K administration. I prefer pt on drips have dedicated line for the insulin.
  12. by   fsh1986
    Quote from daisywill
    Hi. I might be too late but I just saw this post. Potassium is used in rapid situations to push glucose IN the cells. This produces a decrease in SERUM potassium. Thats why kayxelate is used to push glucose into the cells. Hope I helped.
    I know this is old... but I'm confused. I thought Kayexelate was given for hyperkalemia? From what I remember in clinicals, doesn't the Kayexelate switch out sodium for potassium and cause the body to dump potassium?