"24 Hours in A&E" is pretty interesting (also 19 seasons long!), as are "A&E After Dark" and "Barnsley Casualty". The latter gave me an awful shock though as I saw an online friend who I'd never met in person but who I knew lived there. I knew he'd died of cancer but this episode was shot before he died. He'd come into the ER (which is variously called A&E or Casualty) for something, I forget what, and they ended up having to tell him that he was dying and there was basically nothing more they could do for him. No last names were mentioned, but I knew his wife's name and could piece together enough of the story to know who it was. That episode shook me to my shoes. My favorite person in that series, however, was the volunteer Jane, a middle-aged Yorkshirewoman, who was always bustling about with her tea trolley and was just an amazing person. I also watched some of the rescue shows which were interesting, as well. I like "Nightwatch", which shows various arms of the New Orleans fire, EMS, and police as they go about their business on the night shift.
The British reality shows are much different (I think better) than American ones. In the ER ones you get a lot of the back stories of selected patients, many of which are quite amazing and very touching, especially those of the older patients and the ones who lived through WWI, even as children. What a difference in cultures!