People always hate me for saying it but why not practice your large bore IVs on the people that are so inebriated/high/unconscious/drug affected they either wont feel it, remember it, care about it or any combination of the above. When you actually need big bore IVs (read: 14 or 16 gauge) you need it on the first shot and quickly.
With that said, your treatments should never be punitive. If you're starting a huge line because "this guy is an :censored::censored::censored::censored::censored::censored::censored:" you need to check yourself.
I'll say it now and everyone can get upset about it, I often place or have my students place 16g IVs in extremely intoxicated people and don't lose any sleep over it.
As for the max attempts, as a student you get 2 shots unless it's a critical patient that I need access on quickly then it's only one opportunity before I take over.
I agree with what JP said about identifying yourself as a student.
I think I wrote a few volumes on this actually.
first, in my pseudo scientific experiment the difference in nociceptive pain pain from a large bore and a smaller guage is indistinguishable.
(a coworker and I each tried sticking the other blindfolded with both a 14g and an 18g) In 3 of the 4 cases neither of us could accurately tell. In the 4th my partner in crime actually picked the 18g as more painful.
The real difference is largely psychological. So starting a large bore IV on a drunk patient is probably only going to satisfy the anger of the provider. (Not exactly the moral ethical thing, but it happens.)
The other issue is that it takes a different technique to insert a large bore catheter. Like any skill, if you don't do it regularly, you will not be good at it when it counts. That means somebody, sometime, is going to get a larger needle than they "need." It is sort of like animal testing, at some point, there are acceptable losses.
As for the OP, trouble with IVs on the first ED rotation? I wouldn't worry about it at all. Now after 5 years in the field, well, maybe there is a problem then.
Every place I have been, there is a noncritical understood (not written in policy or the like) of 2 attempts before asking for help.
When the pt. is critical, then all bets are off and "whatever it takes" is the only rule.
Chances are on an ambulance, unless you are giving a med, the patient can make it to the hospital before an IV anyway.
As for improving, always ask to try to stick the hardest patients at your clinical location. It is the best way to build the skill.
As a hint, practice extensively on the Basilic and cephalic veins. They are not often visible, they are not on a joint, well above shunt placement, and because of human embryological development, have almost no anatomical deviation. Which means whether a newborn or 300kg 90 year old, it is a reliable option.
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