When I worked the floor, we had certain cnas, that could take a blood pressure off 220/110 and not feel the need to notify us until like 645. Most were great and knew the levels at which we needed to know right away but there was were like 2 who were just plain bad, and because they had 20ish pts to do vitals on we never knew when they were going to do them. As for doing them ourselves, haha what a joke. 7-8+ a night for each RN (med -tele) , 6-7 RNs at night, 2-3 cnas only 4 vital signs carts..... Do the math! Vent away, but my advice to you is take in what you can, figure out what makes you happy and do it. I am in ICU now and I love it.