It was the needle for me, and I’m not usually bothered by needles. The first time I saw a central line placed I had a pretty negative visceral reaction to it, and the first time I saw a LP done I had to sit down. Right then, immediately, or I would have hit my head on something on the way down. Just the thought of a needle that big entering the spinal canal! I could have died on the spot. After a few exposures to each I loved assisting with procedures, which became one of my favorite things to do. During one of my last shifts at work before I started med school, I got to work as my unit resource - and it was a busy as hell night, so I basically followed the intensivist around and assisted with intubations, LPs, central line placements, and chest tubes all night. It was awesome. If you had tried to tell me on that day I almost passed out watching my first LP, that a few years later watching one would be my favorite part of my shift, I would have laughed.
How many CVC inserts, LPs, etc. have you seen, exactly? I’m not going to say you should rule out procedural specialties yet - it took me a bit to warm up when I first watched those types of procedures, and a little bit of fear is healthy.
I’d rather have someone worried about messing up placing a line in me than a cowboy excited to show off, totally unbothered by the potential for complications. Too much fear is debilitating, but just a little makes us more careful.