I am often admitted to hospital due to chronic conditions, when it comes to putting a cannula in or injections (subcutaneous, intramuscular and intradermal)
I always offer to let a student do it, be it nurse or medical student. I have awful veins that collapse as soon as they find them, I also will happily let them poke away, it doesn't bother me as long as they chat and have someone to guide them every so often
The hardest time ever getting blood out of me as I was admitted took 3 days before they finally got the samples they needed, it was taken from my hands, wrists, inner elbow, then went for feet, followed by groin then back of knees, finally got it in the neck. There were no students involved on that occasion, they were all SHOs / Registrars and it was Dr #13 who finally hit red. He was called from the children's ward to try, (medical, surgical, psych (the ward I was on). neurology, dermatology, phlebotomy, anaesthetist all failed)
I was seen by an anaesthetist for an infusion a few years and the consultant went to place the cannula, I warned him, they hide and then collapse. It needed done one way or another and he stated in all his years it was the most awkward canula he ever placed. He got it in a place where he said it shouldn't go and had to put it in a reverse position and I had the dubious honour of being the hardest canulation he had ever done. 30 years as a consultant. He got it on the 9th attempt. He felt he had failed me, no I have awful veins and so during that admission, I literally had every medical student in the hospital around to have a go when I needed another canula placing.