Distinguising the Difference between Diuretics/Potassium Concerns

[aweldon001]

Hey everyone! I'm in the need of a little help. I'm currently studying for NCLEX with my nose deep in my HURST review book and I'm a little confused about diuretics. I know that there's the loop diuretics, such as Lasix and Bumex, there's Hydrochlorothiazide, and then there's the potassium-sparing, such as Aldactone. My question is, which is the one that you worry about hyperkalemia? Does potassium-sparing mean that you retain or excessively excrete potassium? What is patient teaching specifically with each type of diuretic? I want to make sure I have this straight for NCLEX and some of the stuff I'm googling is going over my head. In-depth responses would be greatly appreciated! Thanks!

-A stressed graduate nurse.

[StudentOfHealing]

I'm an SN, but I can try to help.

Think about it this way:

Potassium Sparing Diuretics essentially inhibit aldosterone.

Aldosterone = water retention, potassium excretion, sodium retention. Recall, Aldosterone is activated to raise BP.

If it inhibits the action... Potassium sparing will....

Excrete water and sodium and retain potassium.

So drugs like Aldactone, can cause hyperkalemia... so they should avoid high potassium containing foods and salt substitutes, as these contain KCl.

anyone feel free to correct me.

[aweldon001]

Hey, thanks so much! I needed this little review/reminder. You helped a lot! Much appreciated! :)

[I.C.UNurse]

In a nut shell, you excreting fluid (including Na+, H+ and so on) but keeping the potassium in the system. You are not increasing the K+ with potassium sparing diuretics. You have less circulating fluid, meaning your blood is going to have an increased amount of electrolytes such as K+. Think of it as the same way with burns. Fluid is excreted from the body and potassium is higher in the blood now because it is more concentrated. I know the physiology is different but both problems have more concentrated blood due to fluid loss leading to electrolyte problems.

[KelRN215, BSN, RN]

Potassium sparing diurectics "spare" potassium from excretion so the patient retains more. Other diuretics (such as Lasix) are not potassium sparing and can cause hypOkalemia.