effects of K+ on the heart...

[kimber3ks, ASN, BSN, RN, EMT-B]

thought I had this all nice and neat in my brain, but here it is almost graduation time, and a discussion at clinical this weekend jumbled everything up

I thought that extreme HYPER kalemia would s-l-o-w the heart down to where it would stop beating.

If someone could put HYPER and HYPO kalemia into an easy way to remember I would appreciate it.

Thanks

[Daytonite, BSN, RN]

• hyperkalemia results in slow pulse, oliguria, muscle flaccidity and alkalosis. in the heart the t waves will be peaked, qrs complexes widened and the pr interval prolonged with flat p waves.
  
• hypokalemia results in tachycardia, fatigue, hypotension, and acidosis.

the reason you don't give potassium by direct iv push is because it puts the heart into heart block and asystole resulting in instant death. potassium is never given intravenously any faster than 10meq /hour and should be given diluted in iv fluids, such as a piggyback, via iv pump. if given through a peripheral vein in large concentrations there will generally be local vein irritation. sometimes lidocaine is added to the piggyback to relieve the local vein irritation when amounts of 40 to 60meq of potassium are being infused in piggybacks. extravasation can cause tissue necrosis.

a large dose of iv potassium is the final drug that is given to stop the heart during execution by injection by some state executioners when carrying out a death sentence.