help! Besides insulin, why is potassium given to lower blood glucose?
- 0Feb 3, '06 by azzurra29Hi,
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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- 7Feb 3, '06 by EricJRNThe 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.
- 4Feb 10, '06 by EricJRNGive 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.
- 0Nov 28, '11 by hippal01while 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
- 0Nov 29, '11 by classicdame Guidethanks 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.