Fluids and electrolytes have never been my strong point. Especially electrolytes! Like many so many other students posting here I get confused between hyper/hypo and all the S/Sx. I purchased 'Fluids & Electrolytes Made Incredibly Easy' which is helping some but I'm still lost on some things. I think I'm guilty of not looking at the "big picture".
Today what I can't figure out is why sodium and potassium have an inverse relationship. Last semester in clinical I had a patient who had low sodium and high potassium. I'm still stumped as to why. I probably wouldn't have connected the 2 at all if my professor hadn't called it "interesting" on my care plan. BUN, Creat, and GFR were all normal; the patient was in for something completely unrelated to fluids (kyphoplasty).
Sorry I'm kind of long-winded. Anyway I know there's something I'm missing. The only thing I can think of is something to do with the Sodium Potassium pump? Could someone tell me if I'm even close to being correct or point me toward another electrolytes for dummies resource? :)
In this case the patient had skin tear which leads to fluid loss
When he had skin tear, the cell (ICF) was crushed too and it released the K+ to the ECf since the ECF is more concentrated with K+ then water follows it which makes Na+ to be low in ECF because there is excess water and K+ in ECF and which also makes the patient to be constipated because he doesnt have enough fluid to stimulate his bowel.
The meds explain plenty....I agree with Boston...why was he on Amicar?
Changes in electrolytes is not always "fluid" (excess/dehydration) related. Sometimes, cells release too much potassium. Releasing too much potassium can result from:
Breakdown of red blood cells, called hemolysis
Breakdown of muscle tissue, called rhabdomyolysis
Burns, trauma, or other tissue injury
This is one way to help you remember the causes of hyperkalemia-- high serum potassium-- and the normals.
Normal serum sodium: big number or small number? Answer, big number, 135-145
Normal serum potassium: big number or small number? Answer, small number, 3.5-4.5 ( a nice little bit of symmetry there)
Why is that? Because there is lots of K+ inside the cells, not in the serum, and there is lots of sodium on the serum but not in the cells. It's leakage and exchange across the cell membrane that's responsible for a lot of stuff happening, like why you need a sodium pump to put it back.
If you get cellular destruction (hemolysis, rhabdomyolysis, etc.) then the K+ that's inside the cells escapes, raising the serum potassium.
Also, small trivia bit: Old banked blood is prone to red cell degradation ... so old blood can raise serum K+ (!!!)
Another annoying trivia bit: Some people have really efficient and hardworking sodium pumps; others get the job done but are not so hard-working. Since the metabolic energy to run these little guys can vary, this may be one reason why some people stay skinnier-- their sodium pumps are doing a lot of work all day and night, more than in fatter people. See, I told you that would be annoying, and soooooo unfair!!
loving2024, BSN, RN
347 Posts
In this case the patient had skin tear which leads to fluid loss
When he had skin tear, the cell (ICF) was crushed too and it released the K+ to the ECf since the ECF is more concentrated with K+ then water follows it which makes Na+ to be low in ECF because there is excess water and K+ in ECF and which also makes the patient to be constipated because he doesnt have enough fluid to stimulate his bowel.