Don't stress about it too much. I started anesthesia clinicals with very little IV experience, for the same reason you mentioned (all my ICU patients already had tons of access). When we first started clinicals, a lot of my classmates and I would complain "I suck at IVs." You'll get plenty of opportunities to start IVs in anesthesia school, and in my experience most preceptors are understanding and are pretty cool about giving you tips. I've only encountered one CRNA who made a comment that SRNAs should be proficient in IV starts when they start clinicals, but this CRNA is a pretty nasty and judgmental person.
So, get some practice if/when you can, but don't stress about it too much. An article I found very helpful when learning how to do IV starts was from the journal
Nursing2005. The title of the article is
On the road to successful IV starts. I tried to upload the PDF here but didn't succeed.
Good luck!
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