McCoy: Dialysis?! What is this? The Dark Ages? Here! You swallow that and if you have any more problems, just call me!
All very plausible for what a doctor visiting from the 23rd century might think of today's medical practices. Not to knock today's doctors, who are doing what they can with available technology.
Another fictional reference to dialysis, but not a movie. In the MASH episode "A War for All Seasons" (1980) they build an improvised dialysis machine using sausage casings. That may even have been the first time I heard of dialysis, and it is something that stuck in my mind ever since.
Kolff used sausage casings to accomplish the first successful dialysis treatment - he built the first machine during WWII in occupied Holland (NY Times link). MASH episode : Plausible
I wouldn't expect that 'Hollywood' would consider dialysis as any sort of a plausibly interesting scene. Sitting on your @$$ for 4 hours in a harshly-lit medical facility? Good god, I can see people getting up to buy popcorn already......Let's face it; dialysis may be scary, but for the most part, it's just plain DULL.