Ugh. This post brings back bad memories of my own student clinicals. So few of the nurses wanted anything to do with us, and the ones who were forced to work with us either ignored us or hid from us. Some of the blame must fall to your clinical instructor. Our clinicals improved (slightly) when we got a clinical instructor who worked at the hospital where our clinicals were held. Apparently it's a little harder to be rude and condescending to someone who you will have to work around in the future.
Because of my own past experiences, I have gone out of my way to welcome students into our ICU and always offer to work with them when I can. I have rarely regretted agreeing to work with a student and only then because I had a really busy/crazy day and know that they didn't get to do much besides follow me around.
Some nurses are going to be less than welcoming no matter what you do, but there may be a few things students can do to make themselves more welcome on the floor. One student automatically started changing my patient's bed linen right after we had gotten him out of the bed after extubation. I remembered that thoughtful gesture and asked specifically to work with that student again. Also, while I like answering questions, there is a time and place. If I look super busy and distracted (probably more often than I wish I did) maybe that's not the time to ask a very detailed question. Write down questions to ask later during lulls in the workload. One student did that, and it worked really well for both of us.
While I understand that students are not placed in our unit to do scut work, my ICU has no nurses aids and so doing any of that sort of work for me (serving meals, helping to turn patients, toileting patients, emptying foleys) frees up time for me that I can spend helping them to learn some of the more interesting and challenging stuff.
This too shall pass! I once got YELLED at by a CNA when I was a student and just trying to help. I left clinicals that day on the verge of tears. I now work in the same hospital where that happened and I see that CNA often during my rapid response rounding on the med-surg floors. Now that I've had a chance to get to know her, I realize that she yelled at me because she is incompetent and stupid, and I was the only person lower than her that she could take out her frustrations on. She is lucky that I'm not a vindictive person.
Hang in there, students, and try to remember how crappy it felt not to be welcome so that you can change things when you are the nurses.