I really love hospital dramas, and have watched the following:
I especially like it when the drama focuses on the ER department. Also, I'm not a huge fan of hospital politics, so I rather the drama focus on the team of doctors / nurses saving patients and either have hospital politics as a small side-story, or have no hospital politics at all.
I will start on Hospital Playlist when it ends (to ensure that it's not an open ending), so there's no need to recommend me that drama.
From top down, order of recommendation:
Life. Has really well rounded characters, but not a lot of individual cases, as the main focus was the politics. Watching this ruined hospital politics in any other drama for me, so I recommend trying it, it's on a whole other level. Also from one of my favourite screenwriters, anyone will love it if they love the genre. Multiple main leads.
Hospital Playlist. Currently airing, could very well usurp Life as my favourite medical drama. Also from some very trusted screenwriters. Multiple main leads. EDIT: Woops you said I didn't need to rec this, oh well.
Kounodori. Hands down, my favourite Jdrama. Also my favourite medical Jdrama by default, this is full of beautiful human stories about life (and sometimes death). Only a Jdrama can achieve this.
Cross. Starts in a prison, but later on it's mostly in a hospital. Great revenge and redemption story. It focuses on organ transplants and really only follows one doctor on his journey, although there's some great side characters.
Dr John. Not the best, but not the worst, although I can't say how accurate it is in its information. Again, it starts in a prison, but shifts to a hospital setting. It's also a romance, but I watched it because of the actors and it was decent (the politics weren't too bad).
D-Day. I dropped it, but you may be interested. It's a what-if for an extreme earth-quake in Seoul and the aftermath, from the perspective of the doctors. It could have been very good without the intrusive and unnecessary hospital politics, but you may be able to overlook that.
Heart Surgeons. So far I've only seen the first episode, but it's on my PTW list. Looks like what you want, although I can't really judge how good it is.
Good Doctor. There's choices, it's been adapted in many countries, but the Kdrama is the original. There's also a Jdrama version. It's about a doctor with Savant syndrome, but I was very irritated with the Kdrama vers, as there was some misinformation. Anyway, it's about someone wanting to save lives, but the politics may annoy you.
A Poem a Day. It's set in a hospital, but not about doctors. It's about the people who work there but are not doctors. I haven't seen it, but it's on my PTW list and others say it is good.
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Everything except Kounodori is a Kdrama. I hope there's something in there for you.
I second:
Additional:
OMG. I am so excited to recommend, as medical dramas are easily one of my favorite genres. I also agree with you, I really don't like hospital politics. You said you like when the drama focuses on the ER Department, and man do I have one for you.
Emergency Couple. Now you may have heard this name floating around, and I'd say in reference to your criteria it's a must-watch for you. As you can probably tell from the title, the [Korean] drama focuses on the happenings in the ER. And it really has no politics in it. Basically, a divorced couple meet years later as interns in the same hospital, and on the same team. Of course, hilarity ensues. Some people may label it as a cliche, but in my opinion it is not cringy whatsoever and is very well done.
Now the other one I have in mind, just ended last week. It's a Japanese drama called Koi Wa Tsuzuku Yo Dokomade Mo. I have to warn you though, while this drama is a "medical" drama, it really does lean more towards the relationship and romance of the two main characters. I did really enjoy it though, and the cliche's not unbearable to watch. It is not in the ER though (they are cardiologists), and there are no hospital politics either.
The last one is not only my favorite medical drama, but one of my favorite dramas in general. I think a few people above mentioned it too, it's called Doctor John [Korean as well]. Doctor John starts off with the backstory of a doctor sent to jail for euthanizing a criminal, and the controversial aspect of it is incredibly interesting. The doctors in this drama are anesthesiologists, and they deal specifically in pain management. Of course the cast is legendary as well, and you can never go wrong with Ji Sung. There is not too much romance in the drama [there still is], but the drama itself is so interesting that you really forget about it, and it's not that necessary anyway. (There's not really any politics either)
Please let me know which one you choose to watch or if you have any follow up questions!