These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Also, the appearance of Kate, played by Stirling Gallacher.
The two recurring anaesthetists, Keith Greene and Paul Rose.
Magnificent Bastard: Cardio Thoracic surgeon Anton Meyer (George Irving) in the first few series. In the first episode he told a patient that if he (the patient) ever smoked again he (Meyer) would personally undo everything he had done on the operating table.
Memetic Mutation: The female nurses' outfits (i.e. the scrubs worn by the Ensemble Darkhorse extras and Jac Naylor, Mary-Claire Carter and Donna Jackson. Also Jac Naylor's non-medical outfits too.). Certainly popular with students, making the sexy nurse outfit (considered cliched these days) somewhat no longer fashionable or trendy.
Nightmare Fuel: For a supposedly pre-watershed show, this can contain heavy doses of it.
This show has tried to emulate Steven Moffat, but hasn't come close to it though. Not that it fails at being scary (certainly for children anyway).
The Christmas Episode of the show often contains doses of this, even more so than Doctor Who, giving that show a run for its money in the festive season.
Much of the episodes produced by Jane Wallbank fall into this territory.
Periphery Demographic: Popular with high-school age, and college-age students, despite being aimed at adults.