I've had flight nurse friends whom are prior ER nurses apply for CRNA school and be appalled to find out many do not consider it critical care experience. Most who went to an ICU to get experience were surprised the learning curve was much steeper than anticipated.
While I am on a soapbox I also think ER experience should be specifically level one or two (maybe)
Having worked in Level 1s, undesignated centers, and about everything in between I strongly disagree that you get better experience at a level 1 or 2 center.
To start trauma designation does not correlate to medical acuity, states do not require you to see x number of sick medical patients to designate.
Trauma is also one of the easiest things we care for. Especially in EMS and in the ED trauma care is pretty straightforward.
Nursing in a large level 1 means that you do little more than charting and organization. A trauma (and similarly themed for a very sick patient or a code) gets you attendings, residents, fellows, PAs, and so on from the trauma service, general surgery, and the unit. Your ED techs are typically providing what is left of the ‘nursing’ care not done by an attending or medical trainee. Typically pharmacy is drawing and mixing at the bedside, lab collects and sends off samples, et cetera.
Location also plays a big role. A rural center that has high volume is going to likely provide a better teaching experience despite being a lower trauma designation than an urban level 1 where there are multiple centers and patients are quickly taken to OR. As a simple analogy I get a much bigger price of the trauma pie when I’m only sharing with 4 other people instead of 20-30. Also keep in mind that a large number of traumas seen in a level 1 are transfers and have already had a fair bit of stabilizing by the 911 agency, outside ED, and transporting EMS.
It takes much longer to make your way to the trauma bays in a level 1 than a lower designation. It is easy to get stuck in fast track and the medical pods for years before you earn the seniority to work the traumas.
To the ED versus Unit bit, both are critical care just in different ways.
In the ED or EMS the vast majority of patients are not sick, we just have to prove it so we can discharge/treat and release them. A small number of patients are sick, but as they are typically completely unstabilized rapid recognition and treatment is mandatory. Most patients do respond well with basic stabilization, even if they are very sick. I’ve certainly had some patients we end up maxed on 4+ pressors and aggressive vent settings in an hour or two in the ED, but this is incredibly rare.
In the unit patients are (usually) very sick, although also they are typically much more predictable and sudden unexpected decompensation is very rare. Typically I know much more about my patient clinically, and we usually have a pretty good idea of how to manage patients. It is important to remember that not all unit patients are on the verge of death, and there is a fair number of patients who can easily be tripled and still be a pretty slow shift. Like EDs various units will see very different levels of acuity, and depending on the nursing and medical structure can present very different learning experiences for nurses.