I wanted to answer your question about the responsibilites of a CNA in the hospital. My experience is in several areas as a CNA. I worked on an orthopedic floor, as a tech in the ED and as an aide on a dialysis/urology floor. I can tell you that the orthopedic floor was very heavy and required much "back" work. The ED was much easier considering back work because of more assistance from the squads and more responsibilities elsewhere like EKG's, blood draws, transporting and stocking. The urology floor was like that described by LPN n 2005. We have a variety of patients who can need just a urinal handed to them or be fully assisted in a bed bath. But with this, there is additional help when needed.
As far as skills go, I was responsible for BS, VS, I & O's, baths, transfers, ambulation, toileting, d/c'ing heplocks and foleys, and when applicable doing basic dressing changes. Overall, I feel I learned more on my urology floor as a CNA than orthopedic.
My advice would be NOT to work on an orthopedic floor in the hospital, but more of a specialized floor where they have more skills to perform. You will still be able to take care of the patients without killing your back and be more apt to learn skills.