Quote from KaeliF
I do NOT understand it! You would think everyone would be on NS or LR but no, the majority of my patients are on D5 0.45%ns with 20mEq of K. Does anyone else notice this trend or is it just at my hospital? Are the physicians just trying to keep their glucose up (I work on a post surgical floor, a lot of people are NPO after midnight or on clear liquids) and trying to replace K+ cause they are putting out more than they usually do at home due to the fluids going? This is my best guess.
You almost answered yourself in your question, haha
Surgery puts a heavy metabolic demand on the body. Post operatively, nutrition and hydration are important, and there are many obstacles to acheiving these - anesthesia particularly prevents adequate consumption due to post-op N/V. Since they were NPO after midnight, they want to make sure they are addressing metabolic demands - Dextrose particularly is involved, as well as 20 mEq of K to help keep their potassium stable.
The half NS is used primarily because it is hypotonic; that is, it will draw fluid into the cells and promote hydration.
Hope this helps! When in doubt, you can always ask the surgeon. Many of them like to teach about this kind of stuff.