If your friend is injured and can't go to hospital, why not make hospital come to you? Kidnap a doctor and force him to treat your friend.
This plot can be seen from both sides: Doctor may be a protagonist and his kidnappers are bad guys (most likely criminals), or protagonist is kidnapper because he is on the run from the law and can get help officially.
Patient-Doctor relationship adds additional complexity to the story. If you are kidnapped to fix lighting in villain's lair, you are just a slave, nothing more, but Hippocratic Oath actually motivates you.
Anime and Manga
- It happened at least once in Monster, sorta. The protagonist is a doctor - a surgeon, at that - but he's also on the run from the law due to being framed as a serial killer. Thus, he sometimes wind up working as a Crime Doctor of sorts, including situations like these.
- Also, I'm pretty sure it's happened to Black Jack a few times. I definitely remember some mobsters forcing their way into his remote clinic and threatening to kill him unless he fixed their boss's gunshot-wound.
- In the Batman comics, Dr Thomas Wayne (father of Bruce Wayne) was once kidnapped away from a masquerade party to treat the wounds of gangster Lew Moxon.
- The The Indian in the Cupboard series has an unusual variant--the eponymous cupboard can bring plastic figures to life by transporting real people through time. When some of the people transported this way are injured, Omri uses the cupboard to animate a hospital nurse and a WW1 combat medic to treat their wounds.
- In LOST, The Others kidnap Jack in hopes of getting him to operate on a tumor in Ben's spine.
- In Sanctuary, group of criminals kidnapped dr. Will Zimmerman and forced him to treat their boss. Not a wise choice, by the way
- In an episode of Firefly, Simon, their doctor, is kidnapped by a village on a rural planet to tend their people and live their forever. He isn't very happy about it.
- In Fallout: New Vegas this is one possible solution to a quest, useful if your character's own medical skills are too low.
- In the Batman: The Animated Series episode "Paging the Crime Doctor", Leslie Thompkins is kidnapped to perform an emergency surgery on Rupert Thorne.